CINXE.COM
ADW: Circus cyaneus: INFORMATION
<!DOCTYPE html> <html xmlns:og="http://ogp.me/ns#" lang="en" xml:lang="en"> <head> <title>ADW: Circus cyaneus: INFORMATION</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <link rel="canonical" href="https://animaldiversity.org/accounts/Circus_cyaneus/" /> <script type="text/javascript" src="//code.jquery.com/jquery-3.6.0.min.js"></script> <script type="text/javascript" src="//code.jquery.com/jquery-migrate-3.3.2.min.js"></script> <script type="text/javascript" src="/static/js/compat.js"></script> <link rel="shortcut icon" href="https://animaldiversity.org/favicon.ico" /> <link href="//fonts.googleapis.com/css?family=Gentium+Book+Basic:400,400italic,700,700italic" rel="stylesheet" type="text/css" /> <link href="//fonts.googleapis.com/css?family=PT+Sans:400,700,400italic,700italic" rel="stylesheet" type="text/css" /> <link rel="stylesheet" type="text/css" href="/static/bootstrap/css/bootstrap.css" /> <link rel="stylesheet" href="/static/css/pica.styles.css" /> <link rel="stylesheet" href="/static/css/pica.print.css" media="print" /> <!--[if lt IE 9]> <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script> <![endif]--> <link rel="stylesheet" type="text/css" href="/static/colorbox/colorbox.css" /> <meta property="og:url" content="https://animaldiversity.org/accounts/Circus_cyaneus/" /> <meta content="Circus cyaneus (northern harrier)" property="og:title" /> <meta content="website" property="og:type" /> <meta content="Animal Diversity Web" property="og:site_name" /> <meta content="https://animaldiversity.org/collections/contributors/phil_myers/ADW_birds_3_4_03/Falconiformes/harrier0037/medium.jpg" property="og:image" /> <meta name="twitter:card" content="summary" /> <meta name="twitter:site" content="@AnimalDiversity" /> <meta name="twitter:title" content="Circus cyaneus (northern harrier)" /> <meta name="twitter:description" content="Read about Circus cyaneus (northern harrier) on the Animal Diversity Web." /> <meta name="twitter:image:src" content="https://animaldiversity.org/collections/contributors/phil_myers/ADW_birds_3_4_03/Falconiformes/harrier0037/medium.jpg" /> <meta name="twitter:image:height" content="480" /> <meta name="twitter:image:width" content="709" /> <meta name="twitter:url" content="https://animaldiversity.org/accounts/Circus_cyaneus/" /> <script type="text/javascript" src="/static/js/Hyphenator.js"></script> <link rel="stylesheet" href="/static/social-likes/social-likes_birman.css" /> <style> .social-likes { margin: 0; } .social-likes__widget { margin: 0; } </style> <!--[if lt IE 9]> <link rel="stylesheet" type="text/css" href="/static/css/ie.css" /> <![endif]--> <!--[if gt IE 8]> <link rel="stylesheet" type="text/css" href="/static/css/ie9.css" /> <![endif]--> </head> <body> <div id="outerwrap"> <div id="header" aria-role="header"> <h1> <a id="homelink" href="/">Animal Diversity Web</a> </h1> <div class="umlinks"> <div class="relative"> <a href="https://lsa.umich.edu/ummz/" id="ummzlink">University of Michigan Museum of Zoology</a> <a href="https://www.umich.edu/" id="umlink">University of Michigan</a> </div> </div> </div> <div id="wrap" class="gradient"> <div class="container-fluid"> <div class="row-fluid"> <div class="span2 sidebar left"> <ul class="nav nav-tabs nav-stacked" id="sitemap"> <li> <a href="/">Home</a> </li> <li> <a href="/about/">About Us</a> </li> <li> <a href="/animal_names/">About Animal Names</a> </li> <li> <a href="/teach/">Educational Resources</a> </li> <li> <a href="/collections/">Special Collections</a> </li> <li> <a href="/glossary/">Glossary</a> </li> <li> <a href="/accounts/Animalia/">Browse Animalia</a> </li> </ul> <h2 class="offscreen">More Information</h2> <div class="well"> <h3>Additional Information</h3> <ul class="unstyled"> <li> <a href="http://www.biokids.umich.edu/critters/Circus_cyaneus/"> BioKIDS Critter Catalog </a> </li> <li> <a href="http://eol.org/search/?q=Circus cyaneus&search=Go">Encyclopedia of Life</a> </li> </ul> </div> </div> <div class="span7_5 blahblahblah main" aria-role="main"> <h2 class="rank-species">Circus cyaneus<span class="vernacular-name">northern harrier</span><span class="vernacular-name alt-vernacular-name">(Also: hen harrier; marsh hawk)</span></h2> <div class="social-likes" data-counters="no"> <div class="facebook" title="Share link on Facebook">Facebook</div> <div class="twitter" title="Share link on Twitter">Twitter</div> </div> <div class="snapshots" aria-hidden="true"> <ul> <li> <a href="/accounts/Circus_cyaneus/pictures/collections/contributors/phil_myers/ADW_birds_3_4_03/Falconiformes/harrier0037/"> <img alt=" " src="/collections/contributors/phil_myers/ADW_birds_3_4_03/Falconiformes/harrier0037/button.jpg" border="0" /> </a> </li> <li> <a href="/accounts/Circus_cyaneus/pictures/collections/contributors/tanya_dewey/noha2/"> <img alt=" " src="/collections/contributors/tanya_dewey/noha2/button.jpg" border="0" /> </a> </li> <li> <a href="/accounts/Circus_cyaneus/pictures/collections/contributors/phil_myers/ADW_birds_3_4_03/Falconiformes/harrier7189/"> <img alt=" " src="/collections/contributors/phil_myers/ADW_birds_3_4_03/Falconiformes/harrier7189/button.jpg" border="0" /> </a> </li> <li> <a href="/accounts/Circus_cyaneus/pictures/collections/contributors/roberts_french/pcd3941_078/"> <img alt=" " src="/collections/contributors/roberts_french/pcd3941_078/button.jpg" border="0" /> </a> </li> <li> <a href="/accounts/Circus_cyaneus/pictures/collections/contributors/phil_myers/ADW_birds_3_4_03/Falconiformes/harrier7188/"> <img alt=" " src="/collections/contributors/phil_myers/ADW_birds_3_4_03/Falconiformes/harrier7188/button.jpg" border="0" /> </a> </li> </ul> </div> <div class="byline">By Brian Limas</div> <nav class="contents"> <ul> <li> <a href="#geographic_range">Geographic Range</a> </li> <li> <a href="#habitat">Habitat</a> </li> <li> <a href="#physical_description">Physical Description</a> </li> <li> <a href="#reproduction">Reproduction</a> </li> <li> <a href="#lifespan_longevity">Lifespan/Longevity</a> </li> </ul> <ul> <li> <a href="#behavior">Behavior</a> </li> <li> <a href="#communication">Communication and Perception</a> </li> <li> <a href="#food_habits">Food Habits</a> </li> <li> <a href="#predation">Predation</a> </li> <li> <a href="#ecosystem_roles">Ecosystem Roles</a> </li> </ul> <ul> <li> <a href="#economic_importance_positive">Economic Importance for Humans: Positive</a> </li> <li> <a href="#economic_importance_negative">Economic Importance for Humans: Negative</a> </li> <li> <a href="#conservation_status">Conservation Status</a> </li> <li> <a href="#contributors">Contributors</a> </li> <li> <a href="#references">References</a> </li> </ul> </nav> <div class="inner-wrap"> <section class="hyphenate"> <h3 id="geographic_range">Geographic Range</h3> <p audience="advanced">Northern harriers are found throughout the northern hemisphere. In the Americas they breed throughout North America from Alaska and Canadian provinces south of tundra regions south as far as Baja California, New Mexico, Texas, Kansas, and North Carolina. They are only rarely seen breeding in parts of the Atlantic coastal states, such as Vermont, Rhode Island, and Maine and are similarly rare in the arid and mountainous western interior, including most of California, Oregon, and Washington. Their winter range is from southern Canada to the Caribbean and Central America. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <p audience="advanced intermediate">In the Palearctic, northern harriers breed throughout Eurasia, from Portugal in the west, to Lapland and Siberia in the north, and east through China. They winter in northern African and tropical Asia. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <ul class="keywords donthyphenate "> <li class="keywords-header">Biogeographic Regions</li> <li> <a class="gloss" href="#20020914235803">nearctic</a> <ul> <li> <a class="gloss" href="#20020904145365">native</a> </li> </ul> </li> <li> <a class="gloss" href="#20020915001330">palearctic</a> <ul> <li> <a class="gloss" href="#20020904145365">native</a> </li> </ul> </li> <li> <a class="gloss" href="#20020915001348">oriental</a> <ul> <li> <a class="gloss" href="#20020904145365">native</a> </li> </ul> </li> </ul> <ul class="keywords donthyphenate last"> <li class="keywords-header">Other Geographic Terms</li> <li> <a class="gloss" href="#200304045530">holarctic</a> </li> </ul> </section> <section class="hyphenate"> <h3 id="habitat">Habitat</h3> <p audience="advanced intermediate">Northern harriers are found mainly in open habitats such as fields, savannas, meadows, marshes, upland prairies, and desert steppe. They also occur in agricultural areas and riparian zones. Densest populations are found in large expanses of undisturbed, open habitats with dense, low vegetation. In eastern North America northern harriers are found most frequently in wetland habitats. In western North America they are most abundant in upland habitats such as desert steppe. Northern harriers avoid forested and mountainous areas. <span class="citations"> (<a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>)</span></p> <ul class="keywords donthyphenate "> <li class="keywords-header">Habitat Regions</li> <li> <a class="gloss" href="#20020904145595">temperate</a> </li> <li> <a class="gloss" href="#20020904145598">tropical</a> </li> <li> <a class="gloss" href="#20020904145794">terrestrial</a> </li> </ul> <ul class="keywords donthyphenate "> <li class="keywords-header">Terrestrial Biomes</li> <li> <a class="gloss" href="#20020904145599::20020904145583::20020904145682">savanna or grassland</a> </li> <li> <a class="gloss" href="#20020904145505">chaparral</a> </li> </ul> <ul class="keywords donthyphenate "> <li class="keywords-header">Wetlands</li> <li> <a class="gloss" href="#20020904145363">marsh</a> </li> </ul> <ul class="keywords donthyphenate last"> <li class="keywords-header">Other Habitat Features</li> <li> <a class="gloss" href="#20020904145700">agricultural</a> </li> <li> <a class="gloss" href="#20020904145842">riparian</a> </li> </ul> </section> <section class="hyphenate"> <h3 id="physical_description">Physical Description</h3> <p audience="advanced">Northern harriers have several characteristics which distinguish them from other birds. Specialized feathers around their face in the shape of a disk focus sound into their ears. Their wings form a dihedral when in gliding flight, and they have a distinctive white rump patch which is obvious during flight. <span class="citations"> (<a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>)</span></p> <p audience="advanced">Adult harriers have yellow eyes. Adult males are gray on their dorsal side. Ventrally, they are white, except for spots on their chest, and black wingtips. Adult females are a brown color, except for underneath their wings, where there are white stripes. Immature males and females resemble the adult female, but they have a darker shade of brown covering the dorsal side and a brownish rusty color underneath. Immature harriers have brown eyes. <span class="citations"> (<a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>)</span></p> <p audience="advanced intermediate">The length of adult males varies between 41 and 45 cm (16 to 18 in). The length of adult females varies between 45 and 50 cm (18 to 20 in). Typically the wingspan of adult males varies between 97 and 109 cm (38 to 43 in). The wingspan of adult females varies between 111 and 122 cm (44 to 48 in). The weight of adult males is approximately 290 to 390 grams(1/2 to 1 lb). The average weight of adult females is approximately 390 to 600 grams(1 to 1.3lbs). (Wheeler and Clark 1995,Weidensaul 1996,Ryser 1985,Wheeler and Clark 1987) <span class="citations"> (<a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>)</span></p> <ul class="keywords donthyphenate "> <li class="keywords-header">Other Physical Features</li> <li> <a class="gloss" href="#20020916130951">endothermic</a> </li> <li> <span>homoiothermic</span> </li> <li> <a class="gloss" href="#20020904145642">bilateral symmetry</a> </li> </ul> <ul class="keywords donthyphenate last"> <li class="keywords-header">Sexual Dimorphism</li> <li> <span>female larger</span> </li> <li> <span>sexes colored or patterned differently</span> </li> </ul> <ul class="aside block-grid donthyphenate three-up"> <li> <dl> <dt>Range mass</dt> <dd>290 to 600 g</dd> <dd class="english">10.22 to 21.15 oz</dd> </dl> </li> <li> <dl> <dt>Range length</dt> <dd>41 to 50 cm</dd> <dd class="english">16.14 to 19.69 in</dd> </dl> </li> <li> <dl> <dt>Range wingspan</dt> <dd>340 to 384 mm</dd> <dd class="english">13.39 to 15.12 in</dd> </dl> </li> </ul> </section> <section class="hyphenate"> <h3 id="reproduction">Reproduction</h3> <p audience="advanced">Adult males show interesting behaviors during mating season. During mating season the male courts the female by flying high in the air and then dives down twirling and spinning. Males are sometimes polygynous and have 1 to 3 mates. During incubation the male provides food for the female, but he doesn't approach the nest. When he is near the nest he will call out, and as she comes to him he drops the food to her. During the breeding season northern harriers become very territorial and will attack other hawks, birds, or humans that approach their nesting areas. <span class="citations"> (<a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#515d6835aaa4c64109ac24986be04b52" class="citation">Chinery, 1992</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#2368756649a8e1745e7f96ce3d0585fa" class="citation">Ryser, 1985</a>)</span></p> <p audience="advanced">Most males are monogamous, although some males are polygynous, having been known to pair with up to five mates in a season. Females are monogamous. This is due, not only to the female-biased sex ratio, but also to the abundance of food during the spring. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <ul class="keywords donthyphenate last"> <li class="keywords-header">Mating System</li> <li> <a class="gloss" href="#20020904145332">monogamous</a> </li> <li> <a class="gloss" href="#20020904145840">polygynous</a> </li> </ul> <p audience="advanced intermediate">Harriers often nest in loose colonies of 15 to 20 individuals. The nest, built mostly by the female, is made out of sticks and padded on the inside with grass. The nest is built on the ground, often on raised mounds of dirt or clumps of vegetation. <span class="citations"> (<a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>; <a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>)</span></p> <p audience="advanced intermediate">Eggs are laid from mid-May to early June. They are white with a blue tint, and occasionally have brown spots. The eggs are approximately 47 x 36mm. Three to five eggs are laid, and incubation is only by the female. <span class="citations"> (<a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>)</span></p> <p audience="advanced intermediate">The eggs hatch in approximately 31 to 32 days. Male harriers will contribute to the feeding of their offspring during the time they are in the nest and will watch over the nest for a maximum of 5 minutes when the female is away. <span class="citations"> (<a href="#dfad8572a9452c5293d573859d6b6f62" class="citation">Baicich and Harrison, 1997</a>; <a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#e4fca6d509f7324faad0a5a2e285b2f7" class="citation">Terres, 1980</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>)</span></p> <ul class="keywords donthyphenate last"> <li class="keywords-header">Key Reproductive Features</li> <li> <a class="gloss" href="#20020904145554">iteroparous</a> </li> <li> <span>gonochoric/gonochoristic/dioecious (sexes separate)</span> </li> <li> <a class="gloss" href="#20020904145786">sexual</a> </li> <li> <a class="gloss" href="#20020904145572">oviparous</a> </li> </ul> <ul class="aside block-grid donthyphenate three-up"> <li> <dl> <dt>Breeding interval</dt> <dd>Northern harriers breed once per season.</dd> </dl> </li> <li> <dl> <dt>Breeding season</dt> <dd>Primary females breed from April through July, while secondary females breed from May through September.</dd> </dl> </li> <li> <dl> <dt>Range eggs per season</dt> <dd>3 to 5</dd> </dl> </li> <li> <dl> <dt>Average eggs per season</dt> <dd>4.4</dd> </dl> </li> <li> <dl> <dt>Average eggs per season</dt> <dd>5</dd> <dd> <small> <a href="http://genomics.senescence.info/species/entry.php?species=Circus_cyaneus" class="external-link">AnAge</a> </small> </dd> </dl> </li> <li> <dl> <dt>Range time to hatching</dt> <dd>28 to 36 days</dd> </dl> </li> <li> <dl> <dt>Range fledging age</dt> <dd>30 to 35 days</dd> </dl> </li> <li> <dl> <dt>Average age at sexual or reproductive maturity (female)</dt> <dd>2 years</dd> </dl> </li> <li> <dl> <dt>Average age at sexual or reproductive maturity (female)<br /><span>Sex: female</span></dt> <dd>365 days</dd> <dd> <small> <a href="http://genomics.senescence.info/species/entry.php?species=Circus_cyaneus" class="external-link">AnAge</a> </small> </dd> </dl> </li> <li> <dl> <dt>Average age at sexual or reproductive maturity (male)</dt> <dd>3 years</dd> </dl> </li> <li> <dl> <dt>Average age at sexual or reproductive maturity (male)<br /><span>Sex: male</span></dt> <dd>365 days</dd> <dd> <small> <a href="http://genomics.senescence.info/species/entry.php?species=Circus_cyaneus" class="external-link">AnAge</a> </small> </dd> </dl> </li> </ul> <p audience="advanced">Female investment in her offspring begins with the provisioning of yolk to her eggs. After laying, the female will spread her wings to shelter her young from rain and extreme sun. Her mate will provide food for her for about two weeks after the eggs hatch, then departs. Food is transferred to the female via the male by aerial-pass, and then the female feeds her young. When young reach fledgling stage and are able to fly sufficiently well, food transfer is made to them by their mother, also via aerial-pass. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>; <a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>; <a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <ul class="keywords donthyphenate last"> <li class="keywords-header">Parental Investment</li> <li> <a class="gloss" href="#20020904145328">altricial</a> </li> <li> <span>pre-fertilization</span> <ul> <li> <span>provisioning</span> </li> </ul> </li> <li> <span>pre-hatching/birth</span> <ul> <li> <span>provisioning</span> <ul> <li> <span>male</span> </li> <li> <span>female</span> </li> </ul> </li> <li> <span>protecting</span> <ul> <li> <span>male</span> </li> <li> <span>female</span> </li> </ul> </li> </ul> </li> <li> <span>pre-weaning/fledging</span> <ul> <li> <span>provisioning</span> <ul> <li> <span>male</span> </li> <li> <span>female</span> </li> </ul> </li> <li> <span>protecting</span> <ul> <li> <span>female</span> </li> </ul> </li> </ul> </li> <li> <span>pre-independence</span> <ul> <li> <span>provisioning</span> <ul> <li> <span>female</span> </li> </ul> </li> <li> <span>protecting</span> <ul> <li> <span>female</span> </li> </ul> </li> </ul> </li> </ul> </section> <section class="hyphenate"> <h3 id="lifespan_longevity">Lifespan/Longevity</h3> <p audience="advanced intermediate">There is very little information known concerning the lifespan of northern harriers. The longest lifespan reported is 16 years and 5 months. The average lifespan, however, is 16.6 months. The oldest reported breeding female was 8 years old.</p> <ul class="aside block-grid donthyphenate three-up"> <li> <dl> <dt>Range lifespan<br /><span>Status: wild</span></dt> <dd>16.19 (high) years</dd> </dl> </li> <li> <dl> <dt>Average lifespan<br /><span>Status: wild</span></dt> <dd>16.6 months</dd> </dl> </li> <li> <dl> <dt>Average lifespan<br /><span>Status: wild</span></dt> <dd>197 months</dd> <dd> <small> <a href="http://www.pwrc.usgs.gov/BBL/homepage/longvrec.htm" class="external-link">Bird Banding Laboratory</a> </small> </dd> </dl> </li> </ul> </section> <section class="hyphenate"> <h3 id="behavior">Behavior</h3> <p audience="advanced intermediate">Besides flying, northern harriers walk and hop. They use this method of locomotion while retrieving prey, collecting nesting materials, and retrieving nestlings that have strayed from the nest. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>; <a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <p audience="advanced intermediate">Harriers typically fly slow and low to the ground, gliding often, and sometimes seeming to hover. They occasionally soar. Males fly faster and are more agile in flight than either females or juveniles and have been seen overtaking <a class="taxon-link" href="/accounts/Falco_mexicanus/">prairie falcons</a>. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>; <a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <p audience="advanced intermediate">Northern harriers may nest alone or in loose assemblages. Territorial behavior is minimal especially during the breeding season, except at the nest site where both males and females will defend their territory against conspecific intruders. In winter, however, females aggressively exclude males from prime feeding territories. Despite this strong territoriality on the part of females, individuals of both sexes roost on the ground communally during the non-breeding season. During migration, northern harriers, like other raptors, prefer not to fly over open water. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <p audience="advanced intermediate">Northern harriers are active during the day and spend much of their time hunting.</p> <ul class="keywords donthyphenate last"> <li class="keywords-header">Key Behaviors</li> <li> <span>flies</span> </li> <li> <span>glides</span> </li> <li> <a class="gloss" href="#20020904145414">diurnal</a> </li> <li> <a class="gloss" href="#20020904145472">motile</a> </li> <li> <a class="gloss" href="#20020904145313">migratory</a> </li> </ul> <ul class="aside block-grid donthyphenate one-up"> <li> <dl> <dt>Range territory size</dt> <dd>1.7 to 150 km^2</dd> </dl> </li> </ul> <h4>Home Range</h4> <p audience="advanced intermediate">During breeding season both sexes tend to be territorial around the nests, but otherwise, home ranges tend to overlap. Monogamous male territories tend to be approximately 260 ha (2.6 km square) in size, ranging from 170 (1.7 km square) to 15,000 (150 km square) ha. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> </section> <section class="hyphenate"> <h3 id="communication">Communication and Perception</h3> <p audience="advanced">Northern harriers are especially vocal around the nest. Sounds of courtship are reflected by rapid kek, quik, or ek notes in series. Calls of distress are urgent and high pitched, also in rapid succession. This call is more nasal-sounding in males than in females. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <p audience="advanced">There also exists a "food call", which is observed most frequently during breeding season. Females issue a piercing eeyah, eeyah scream, which may be repeated for several minutes. This is responded to by a barely audible purrduk chuckle by the male, which solicits the female from the nest. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <p audience="advanced">Young harriers emit a "begging call" when they hear their parents or in response to seeing their parents fly overhead. This sound is often referred to as a pain call, and it is a series of chit notes. This sound only becomes more emphatic with increasing age. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <p audience="advanced intermediate">Northern harriers, like most raptors, have a keen sense of vision. Northern harriers are unusual in that their owl-like facial ruff enhances their sense of hearing, which they use extensively in finding prey. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <ul class="keywords donthyphenate "> <li class="keywords-header">Communication Channels</li> <li> <a class="gloss" href="#20020904145694">visual</a> </li> <li> <a class="gloss" href="#20020904145822">acoustic</a> </li> </ul> <ul class="keywords donthyphenate last"> <li class="keywords-header">Perception Channels</li> <li> <a class="gloss" href="#20020904145694">visual</a> </li> <li> <a class="gloss" href="#20020904145500">tactile</a> </li> <li> <a class="gloss" href="#20020904145822">acoustic</a> </li> <li> <a class="gloss" href="#20020904145606">chemical</a> </li> </ul> </section> <section class="hyphenate"> <h3 id="food_habits">Food Habits</h3> <p audience="advanced intermediate">The diet is variable, depending on dominant prey types in the area. In areas with large populations of small mammals, they make up 95% of the diet. In northern grasslands, the diet may be almost exclusively <a class="taxon-link rank-genus" href="/accounts/Microtus/">Microtus</a> voles. Northern harriers also eat other small vertebrates, including snakes, frogs, passerine birds, and small waterfowl. When hunting for food, harriers glide at a slow pace close to the ground until prey is found. Harriers then dive quickly to capture it. They may also hide in vegetation, waiting to pounce on prey. They sometimes store extra prey to eat later. <span class="citations"> (<a href="#b5fffafc3ea2d41114e4c7ea4cd32097" class="citation">Dechant, et al., 1998</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>; <a href="#946404f6fa537c25b4ab4d710dbf7a3f" class="citation">Wheeler and Clark, 1987</a>)</span></p> <ul class="keywords donthyphenate "> <li class="keywords-header">Primary Diet</li> <li> <a class="gloss" href="#20020904145419">carnivore</a> <ul> <li> <span>eats terrestrial vertebrates</span> </li> </ul> </li> </ul> <ul class="keywords donthyphenate "> <li class="keywords-header">Animal Foods</li> <li> <span>birds</span> </li> <li> <span>mammals</span> </li> <li> <span>amphibians</span> </li> <li> <span>reptiles</span> </li> </ul> <ul class="keywords donthyphenate last"> <li class="keywords-header">Foraging Behavior</li> <li> <a class="gloss" href="#20020914201317">stores or caches food</a> </li> </ul> </section> <section class="hyphenate"> <h3 id="predation">Predation</h3> <p audience="advanced intermediate">Northern harriers have many predators, including raccoons, skunks, American crows, common ravens, coyotes, feral dogs, red foxes, and great horned owls. American crows and common ravens prey on eggs, while other raptors, especially great horned owls, target nestlings. <span class="citations"> (<a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#515d6835aaa4c64109ac24986be04b52" class="citation">Chinery, 1992</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>; <a href="#2368756649a8e1745e7f96ce3d0585fa" class="citation">Ryser, 1985</a>)</span></p> <p audience="advanced intermediate">Northern harriers with young generally respond aggressively to predators. Defense ranges from aggressive distress calls to striking the intruder with closed talons. Males and females contribute equally to defense. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <p audience="advanced intermediate">Northern harriers often compete with <a class="taxon-link" href="/accounts/Asio_flammeus/">short eared owls</a> for the same food source. Food shortages can occur because both hunt the same prey. Northern harriers have a tendency to steal prey away from short eared owls by harassing them until the owl drops its prey. Short eared owls have been known to hunt both at night and during the day, while northern harriers hunt only during the day. <span class="citations"> (<a href="#9d2bcc28e234a3bd190cad9454b7a9f4" class="citation">Burton and Burton, 1989</a>; <a href="#515d6835aaa4c64109ac24986be04b52" class="citation">Chinery, 1992</a>; <a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#2368756649a8e1745e7f96ce3d0585fa" class="citation">Ryser, 1985</a>)</span></p> <ul class="aside block-grid donthyphenate one-up"> <li> <dl> <dt>Known Predators</dt> <dd> <ul> <li>American crow <a class="taxon-link rank-species" href="/accounts/Corvus_brachyrhynchos/">Corvus brachyrhynchos</a> </li> <li>common ravens (<a class="taxon-link rank-species" href="/accounts/Corvus_corax/">Corvus corax</a>)</li> <li>coyotes (<a class="taxon-link rank-species" href="/accounts/Canis_latrans/">Canis latrans</a>)</li> <li>great horned owls (<a class="taxon-link rank-species" href="/accounts/Bubo_virginianus/">Bubo virginianus</a>)</li> <li>feral dogs (<a class="taxon-link rank-subspecies" href="/accounts/Canis_lupus_familiaris/">Canis lupus familiaris</a>)</li> <li>striped skunks (<a class="taxon-link rank-species" href="/accounts/Mephitis_mephitis/">Mephitis mephitis</a>)</li> <li>red foxes (<a class="taxon-link rank-species" href="/accounts/Vulpes_vulpes/">Vulpes vulpes</a>)</li> <li>raccoons (<a class="taxon-link rank-species" href="/accounts/Procyon_lotor/">Procyon lotor</a>)</li> </ul> </dd> </dl> </li> </ul> </section> <section class="hyphenate"> <h3 id="ecosystem_roles">Ecosystem Roles</h3> <p audience="advanced intermediate">Predation by northern harriers can have significant effects on populations of field mice and other rodents. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <p audience="advanced intermediate">As prey, northern harriers provide food for some terrestrial predators, such as coyotes <a class="taxon-link rank-species" href="/accounts/Canis_latrans/">Canis latrans</a>, striped skunks <a class="taxon-link rank-species" href="/accounts/Mephitis_mephitis/">Mephitis mephitis</a>, raccoons <a class="taxon-link rank-species" href="/accounts/Procyon_lotor/">Procyon lotor</a>, and red foxes <a class="taxon-link rank-species" href="/accounts/Vulpes_vulpes/">Vulpes vulpes</a>.</p> </section> <section class="hyphenate"> <h3 id="economic_importance_positive">Economic Importance for Humans: Positive</h3> <p audience="advanced intermediate">Northern harriers help protect crops by reducing populations of field mice and other rodents. Unlike some other hawk species, they do not attack poultry. <span class="citations"> (<a href="#89cb62ead6458ebb6f7ac7d2d1e42f95" class="citation">Eastman, 1999</a>; <a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <ul class="keywords donthyphenate last"> <li class="keywords-header">Positive Impacts</li> <li> <span>controls pest population</span> </li> </ul> </section> <section class="hyphenate"> <h3 id="economic_importance_negative">Economic Importance for Humans: Negative</h3> <p audience="advanced intermediate">There are no negative affects of northern harriers on humans. <span class="citations"> (<a href="#515d6835aaa4c64109ac24986be04b52" class="citation">Chinery, 1992</a>; <a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> </section> <section class="hyphenate"> <h3 id="conservation_status">Conservation Status</h3> <p audience="advanced intermediate">No conservation measures have been enacted specifically for this species, however, conservation measures for waterfowl and habitat management for game birds has increased local numbers of nesting northern harriers. The species is abundant enough to be rated "Least Concern" by the IUCN. It it protected under the Migratory Bird Treaty, and is listed in Appendix II of CITES. <span class="citations"> (<a href="#33098d328cd4345f83d9f641ad3c8469" class="citation">Macwhirter and Bildstein, 1996</a>)</span></p> <ul class="aside block-grid donthyphenate three-up"> <li> <dl> <dt> <a class="external-link" href="http://www.iucnredlist.org/">IUCN Red List</a> </dt> <dd> <span>Least Concern</span> <br /> <small> <a class="external-link" href="http://www.iucnredlist.org/apps/redlist/details/144378"> More information </a> </small> </dd> </dl> </li> <li> <dl> <dt> <a class="external-link" href="http://www.iucnredlist.org/">IUCN Red List</a> </dt> <dd> <span>Least Concern</span> <br /> <small> <a class="external-link" href="http://www.iucnredlist.org/apps/redlist/details/144378"> More information </a> </small> </dd> </dl> </li> <li> <dl> <dt> <a class="external-link" href="http://www.fws.gov/migratorybirds/RegulationsPolicies/mbta/mbtintro.html">US Migratory Bird Act</a> </dt> <dd> <span>Protected</span> </dd> </dl> </li> <li> <dl> <dt> <a class="external-link" href="http://www.fws.gov/endangered/">US Federal List</a> </dt> <dd> <span>No special status</span> </dd> </dl> </li> <li> <dl> <dt> <a class="external-link" href="http://www.cites.org/eng/app/appendices.php">CITES</a> </dt> <dd> <span>Appendix II</span> </dd> </dl> </li> </ul> </section> <section class="hyphenate"> <h3 id="contributors">Contributors</h3> <p>Lauren Pajerski (editor), Undergraduate Research Opportunity Program, University of Michigan, George Hammond (editor), Animal Diversity Web, Tanya Dewey (editor), Animal Diversity Web. </p> <p>Brian Limas (author), Fresno City College, Carl Johansson (editor), Fresno City College. </p> </section> <section class="offscreen"> <h3 id="glossary">Glossary</h3> <div id="20020914235803"> <dl> <dt>Nearctic</dt> <dd> <p>living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.</p> <p align="center"> <img alt="World Map" src="/images/worldmap.2001.jpg" /> </p> </dd> </dl> </div> <div id="20020915001330"> <dl> <dt>Palearctic</dt> <dd> <p>living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.</p> <p align="center"> <img alt="World Map" src="/images/worldmap.2001.jpg" /> </p> </dd> </dl> </div> <div id="20020904145822"> <dl> <dt>acoustic</dt> <dd> <p>uses sound to communicate</p> </dd> </dl> </div> <div id="20020904145700"> <dl> <dt>agricultural</dt> <dd> <p>living in landscapes dominated by human agriculture.</p> </dd> </dl> </div> <div id="20020904145328"> <dl> <dt>altricial</dt> <dd> <p>young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.</p> </dd> </dl> </div> <div id="20020904145642"> <dl> <dt>bilateral symmetry</dt> <dd> <p>having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.</p> </dd> </dl> </div> <div id="20020904145419"> <dl> <dt>carnivore</dt> <dd> <p>an animal that mainly eats meat</p> </dd> </dl> </div> <div id="20020904145505"> <dl> <dt>chaparral</dt> <dd> <p>Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.</p> </dd> </dl> </div> <div id="20020904145606"> <dl> <dt>chemical</dt> <dd> <p>uses smells or other chemicals to communicate</p> </dd> </dl> </div> <div id="20020904145414"> <dl> <dt>diurnal</dt> <dd> <ol class="arabic simple"> <li>active during the day, 2. lasting for one day.</li> </ol> </dd> </dl> </div> <div id="20020916130951"> <dl> <dt>endothermic</dt> <dd> <p>animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.</p> </dd> </dl> </div> <div id="200304045530"> <dl> <dt>holarctic</dt> <dd> <p>a distribution that more or less circles the Arctic, so occurring in both the Nearctic and Palearctic biogeographic regions.</p> <p align="center"> <img alt="World Map" src="/images/worldmap.2001.jpg" /> </p> <p>Found in northern North America and northern Europe or Asia.</p> </dd> </dl> </div> <div id="20020904145554"> <dl> <dt>iteroparous</dt> <dd> <p>offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).</p> </dd> </dl> </div> <div id="20020904145363"> <dl> <dt>marsh</dt> <dd> <p>marshes are wetland areas often dominated by grasses and reeds.</p> </dd> </dl> </div> <div id="20020904145313"> <dl> <dt>migratory</dt> <dd> <p>makes seasonal movements between breeding and wintering grounds</p> </dd> </dl> </div> <div id="20020904145332"> <dl> <dt>monogamous</dt> <dd> <p>Having one mate at a time.</p> </dd> </dl> </div> <div id="20020904145472"> <dl> <dt>motile</dt> <dd> <p>having the capacity to move from one place to another.</p> </dd> </dl> </div> <div id="20020904145365"> <dl> <dt>native range</dt> <dd> <p>the area in which the animal is naturally found, the region in which it is endemic.</p> </dd> </dl> </div> <div id="20020915001348"> <dl> <dt>oriental</dt> <dd> <p>found in the oriental region of the world. In other words, India and southeast Asia.</p> <p align="center"> <img alt="World Map" src="/images/worldmap.2001.jpg" /> </p> </dd> </dl> </div> <div id="20020904145572"> <dl> <dt>oviparous</dt> <dd> <p>reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.</p> </dd> </dl> </div> <div id="20020904145840"> <dl> <dt>polygynous</dt> <dd> <p>having more than one female as a mate at one time</p> </dd> </dl> </div> <div id="20020904145842"> <dl> <dt>riparian</dt> <dd> <p>Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).</p> </dd> </dl> </div> <div id="20020904145786"> <dl> <dt>sexual</dt> <dd> <p>reproduction that includes combining the genetic contribution of two individuals, a male and a female</p> </dd> </dl> </div> <div id="20020914201317"> <dl> <dt>stores or caches food</dt> <dd> <p>places a food item in a special place to be eaten later. Also called "hoarding"</p> </dd> </dl> </div> <div id="20020904145500"> <dl> <dt>tactile</dt> <dd> <p>uses touch to communicate</p> </dd> </dl> </div> <div id="20020904145595"> <dl> <dt>temperate</dt> <dd> <p>that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).</p> </dd> </dl> </div> <div id="20020904145794"> <dl> <dt>terrestrial</dt> <dd> <p>Living on the ground.</p> </dd> </dl> </div> <div id="20020904145598"> <dl> <dt>tropical</dt> <dd> <p>the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.</p> </dd> </dl> </div> <div id="20020904145599::20020904145583::20020904145682"> <dl> <dt>tropical savanna and grassland</dt> <dd> <p>A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.</p> </dd> <dt>savanna</dt> <dd> <p>A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.</p> </dd> <dt>temperate grassland</dt> <dd> <p>A terrestrial biome found in temperate latitudes (>23.5掳 N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.</p> </dd> </dl> </div> <div id="20020904145694"> <dl> <dt>visual</dt> <dd> <p>uses sight to communicate</p> </dd> </dl> </div> </section> <section class="hyphenate"> <h3 id="references">References</h3> <p id="dfad8572a9452c5293d573859d6b6f62">Baicich, P., C. Harrison. 1997. <span style="font-style: italic">A Guide to the Nests, Eggs, and Nestlings of North American Birds</span>. New York City, New York, USA: Academic Press. </p> <p id="9d2bcc28e234a3bd190cad9454b7a9f4">Burton, M., R. Burton. 1989. Northern harrier. Pp. 1162 in <span style="font-style: italic">The Marshall Cavendish International Wildlife Encyclopedia</span>, Vol. 10. Toronto, Canada: Marshall Cavendish Corporation. </p> <p id="515d6835aaa4c64109ac24986be04b52">Chinery, M. 1992. Pp. 144 in <span style="font-style: italic">The Kingfisher Illustrated Encyclopedia of Animals</span>. New York: Kingfisher Books. </p> <p id="b5fffafc3ea2d41114e4c7ea4cd32097">Dechant, J., M. Sondreal, D. Johnson, L. Igl, C. Goldade. 1998. "Effects of management practices on grassland birds: Northern Harrier.." (On-line). Accessed September 15, 2000 at <tt><a href="http://www.npwrc.usgs.gov/resource/literatr/grasbird/harrier/harrier.htm">http://www.npwrc.usgs.gov/resource/literatr/grasbird/harrier/harrier.htm</a></tt>. </p> <p id="89cb62ead6458ebb6f7ac7d2d1e42f95">Eastman, J. 1999. <span style="font-style: italic">Birds of Lake, Pond, and Marsh</span>. Pennsylvania, USA: Stackpole Books. </p> <p id="33098d328cd4345f83d9f641ad3c8469">Macwhirter, R., K. Bildstein. 1996. Northern Harrier. <span style="font-style: italic">The Birds of North America</span>, 210: 1-25. </p> <p id="2368756649a8e1745e7f96ce3d0585fa">Ryser, F. 1985. <span style="font-style: italic">Birds of the Great Basin- A Natural History</span>. Reno, Las Vegas: University of Nevada Press. </p> <p id="913f69ba9045f8e14742a310c6255157">Snyder, N., H. Snyder. 1991. <span style="font-style: italic">Birds of Prey- Natural History and Conservation of North American Raptors</span>. MN.: Voyageur Press Inc.. </p> <p id="e4fca6d509f7324faad0a5a2e285b2f7">Terres, J. 1980. Pp. 483 in <span style="font-style: italic">The Audubon Society Encyclopedia of North American Birds</span>. New York: Alfred A.Knoph Inc.. </p> <p id="617fc77faee14b58decea44dab9729c0">Weidensaul, S. 1996. <span style="font-style: italic">Raptors-The Birds of Prey</span>. New York: Lyons and Burford. </p> <p id="6ca176064f31f9246d5604e76b85f7eb">Wheeler, B., W. Clark. 1995. <span style="font-style: italic">A Photographic Guide to North American Raptors</span>. San Diego: Academic Press Inc.. </p> <p id="946404f6fa537c25b4ab4d710dbf7a3f">Wheeler, B., W. Clark. 1987. <span style="font-style: italic">The Peterson Field Guide Series- A Field Guide to Hawks of North America</span>. Boston: Houghton Mifflin Company. </p> </section> </div> </div> <div class="span2_5 right sidebar"> <div class="well" id="pocket-guide-link"> <a href="https://itunes.apple.com/us/app/adw-pocket-guide/id916179421?mt=8" target="_blank"><i class="icon-download icon-white" style="vertical-align: bottom"></i> ADW Pocket Guides on the iOS App Store! </a> <p>The Animal Diversity Web team is excited to announce ADW Pocket Guides!</p> <p> <a href="/news/5009059054038197651/">Read more...</a> </p> </div> <h2 class="offscreen">Search</h2> <div id="site-search"> <form action="/search" method="GET"> <label for="q" class="offscreen">Enter search text</label> <input value="" id="q" name="q" class="span12" size="15" type="text" placeholder="Search ADW" /> <button class="btn"> <i class="icon-zoom-in"></i> <span class="offscreen">Search</span> </button> <p style="max-height: 35px"> <label for="feature-list" class="offscreen">Search in feature</label> <select size="1" name="feature" class="feature-list input-medium" id="feature-list"> <option value="INFORMATION">Taxon Information</option> <option value="COLLECTIONS">Contributor Galleries</option> <option value="TOPICS">Topics</option> <option value="CLASSIFICATION">Classification</option> </select> </p> </form> <ul class="unstyled"> <li> <a href="https://animaldiversity.ummz.umich.edu/quaardvark/">Explore Data @ Quaardvark</a> </li> <li> <a href="/search_guide/">Search Guide</a> </li> </ul> </div> <h2 class="offscreen">Navigation Links</h2> <dl class="tabbed features"> <dd class="feature-information active"> <a name="feature-information" href="/accounts/Circus_cyaneus/" class="active" id="feature-information"> Information </a> </dd> <dd class="feature-pictures"> <a name="feature-pictures" href="/accounts/Circus_cyaneus/pictures/" id="feature-pictures"> Pictures </a> </dd> <dd class="feature-sounds"> <a name="feature-sounds" href="/accounts/Circus_cyaneus/sounds/" id="feature-sounds"> Sounds </a> </dd> <dd class="feature-classification"> <a name="feature-classification" href="/accounts/Circus_cyaneus/classification/#Circus_cyaneus" id="feature-classification"> Classification </a> </dd> </dl> <div class="classification well"> <h3>Classification</h3> <ul class="unstyled"> <li> <span class="rank">Kingdom</span> <a href="/accounts/Animalia/" class="taxon-name rank-kingdom">Animalia</a> <span class="vernacular-name">animals</span> <div class="features"> <a href="/accounts/Animalia/" class="feature feature-information" rel="tooltip" data-original-title="Animalia: information (1)" data-delay="250" data-total="4749">Animalia: information (1)</a> <a href="/accounts/Animalia/pictures/" class="feature feature-pictures" rel="tooltip" data-original-title="Animalia: pictures (22861)" data-delay="250">Animalia: pictures (22861)</a> <a href="/accounts/Animalia/specimens/" class="feature feature-specimens" rel="tooltip" data-original-title="Animalia: specimens (7109)" data-delay="250">Animalia: specimens (7109)</a> <a href="/accounts/Animalia/sounds/" class="feature feature-sounds" rel="tooltip" data-original-title="Animalia: sounds (722)" data-delay="250">Animalia: sounds (722)</a> <a href="/accounts/Animalia/maps/" class="feature feature-maps" rel="tooltip" data-original-title="Animalia: maps (42)" data-delay="250">Animalia: maps (42)</a> </div> </li> <li> <span class="rank">Phylum</span> <a href="/accounts/Chordata/" class="taxon-name rank-phylum">Chordata</a> <span class="vernacular-name">chordates</span> <div class="features"> <a href="/accounts/Chordata/" class="feature feature-information" rel="tooltip" data-original-title="Chordata: information (1)" data-delay="250" data-total="3902">Chordata: information (1)</a> <a href="/accounts/Chordata/pictures/" class="feature feature-pictures" rel="tooltip" data-original-title="Chordata: pictures (15213)" data-delay="250">Chordata: pictures (15213)</a> <a href="/accounts/Chordata/specimens/" class="feature feature-specimens" rel="tooltip" data-original-title="Chordata: specimens (6829)" data-delay="250">Chordata: specimens (6829)</a> <a href="/accounts/Chordata/sounds/" class="feature feature-sounds" rel="tooltip" data-original-title="Chordata: sounds (709)" data-delay="250">Chordata: sounds (709)</a> <span class="feature-off feature-maps"></span> </div> </li> <li> <span class="rank">Subphylum</span> <a href="/accounts/Vertebrata/" class="taxon-name rank-subphylum">Vertebrata</a> <span class="vernacular-name">vertebrates</span> <div class="features"> <a href="/accounts/Vertebrata/" class="feature feature-information" rel="tooltip" data-original-title="Vertebrata: information (1)" data-delay="250" data-total="3899">Vertebrata: information (1)</a> <a href="/accounts/Vertebrata/pictures/" class="feature feature-pictures" rel="tooltip" data-original-title="Vertebrata: pictures (15168)" data-delay="250">Vertebrata: pictures (15168)</a> <a href="/accounts/Vertebrata/specimens/" class="feature feature-specimens" rel="tooltip" data-original-title="Vertebrata: specimens (6827)" data-delay="250">Vertebrata: specimens (6827)</a> <a href="/accounts/Vertebrata/sounds/" class="feature feature-sounds" rel="tooltip" data-original-title="Vertebrata: sounds (709)" data-delay="250">Vertebrata: sounds (709)</a> <span class="feature-off feature-maps"></span> </div> </li> <li> <span class="rank">Class</span> <a href="/accounts/Aves/" class="taxon-name rank-class">Aves</a> <span class="vernacular-name">birds</span> <div class="features"> <a href="/accounts/Aves/" class="feature feature-information" rel="tooltip" data-original-title="Aves: information (1)" data-delay="250" data-total="887">Aves: information (1)</a> <a href="/accounts/Aves/pictures/" class="feature feature-pictures" rel="tooltip" data-original-title="Aves: pictures (7311)" data-delay="250">Aves: pictures (7311)</a> <a href="/accounts/Aves/specimens/" class="feature feature-specimens" rel="tooltip" data-original-title="Aves: specimens (153)" data-delay="250">Aves: specimens (153)</a> <a href="/accounts/Aves/sounds/" class="feature feature-sounds" rel="tooltip" data-original-title="Aves: sounds (676)" data-delay="250">Aves: sounds (676)</a> <span class="feature-off feature-maps"></span> </div> </li> <li> <span class="rank">Order</span> <a href="/accounts/Falconiformes/" class="taxon-name rank-order">Falconiformes</a> <span class="vernacular-name">diurnal birds of prey</span> <div class="features"> <span class="feature-off feature-information"></span> <a href="/accounts/Falconiformes/pictures/" class="feature feature-pictures" rel="tooltip" data-original-title="Falconiformes: pictures (439)" data-delay="250">Falconiformes: pictures (439)</a> <a href="/accounts/Falconiformes/specimens/" class="feature feature-specimens" rel="tooltip" data-original-title="Falconiformes: specimens (9)" data-delay="250">Falconiformes: specimens (9)</a> <a href="/accounts/Falconiformes/sounds/" class="feature feature-sounds" rel="tooltip" data-original-title="Falconiformes: sounds (21)" data-delay="250">Falconiformes: sounds (21)</a> <span class="feature-off feature-maps"></span> </div> </li> <li> <span class="rank">Family</span> <a href="/accounts/Accipitridae/" class="taxon-name rank-family">Accipitridae</a> <span class="vernacular-name">eagles, hawks, and kites</span> <div class="features"> <a href="/accounts/Accipitridae/" class="feature feature-information" rel="tooltip" data-original-title="Accipitridae: information (1)" data-delay="250" data-total="53">Accipitridae: information (1)</a> <a href="/accounts/Accipitridae/pictures/" class="feature feature-pictures" rel="tooltip" data-original-title="Accipitridae: pictures (305)" data-delay="250">Accipitridae: pictures (305)</a> <a href="/accounts/Accipitridae/specimens/" class="feature feature-specimens" rel="tooltip" data-original-title="Accipitridae: specimens (4)" data-delay="250">Accipitridae: specimens (4)</a> <a href="/accounts/Accipitridae/sounds/" class="feature feature-sounds" rel="tooltip" data-original-title="Accipitridae: sounds (13)" data-delay="250">Accipitridae: sounds (13)</a> <span class="feature-off feature-maps"></span> </div> </li> <li> <span class="rank">Genus</span> <a href="/accounts/Circus/" class="taxon-name rank-genus">Circus</a> <span class="vernacular-name">harriers</span> <div class="features"> <span class="feature-off feature-information"></span> <a href="/accounts/Circus/pictures/" class="feature feature-pictures" rel="tooltip" data-original-title="Circus: pictures (14)" data-delay="250">Circus: pictures (14)</a> <span class="feature-off feature-specimens"></span> <a href="/accounts/Circus/sounds/" class="feature feature-sounds" rel="tooltip" data-original-title="Circus: sounds (1)" data-delay="250">Circus: sounds (1)</a> <span class="feature-off feature-maps"></span> </div> </li> <li class="active"> <span class="rank">Species</span> <a href="/accounts/Circus_cyaneus/" class="taxon-name rank-species">Circus cyaneus</a> <span class="vernacular-name">northern harrier</span> <div class="features"> <a href="/accounts/Circus_cyaneus/" class="feature feature-information" rel="tooltip" data-original-title="Circus cyaneus: information (1)" data-delay="250" data-total="1">Circus cyaneus: information (1)</a> <a href="/accounts/Circus_cyaneus/pictures/" class="feature feature-pictures" rel="tooltip" data-original-title="Circus cyaneus: pictures (14)" data-delay="250">Circus cyaneus: pictures (14)</a> <span class="feature-off feature-specimens"></span> <a href="/accounts/Circus_cyaneus/sounds/" class="feature feature-sounds" rel="tooltip" data-original-title="Circus cyaneus: sounds (1)" data-delay="250">Circus cyaneus: sounds (1)</a> <span class="feature-off feature-maps"></span> </div> </li> </ul> </div> </div> </div> </div> </div> <div id="footer" aria-role="contentinfo"> <div class="inner-footer"> <div class="page-citation"> <p class="content">To cite this page: Limas, B. 2001. "Circus cyaneus" (On-line), Animal Diversity Web. Accessed December 03, 2024 at https://animaldiversity.org/accounts/Circus_cyaneus/</p> </div> <div class="disclaimer"> <p class="content"><strong>Disclaimer:</strong> The Animal Diversity Web is an educational resource <strong>written largely by and for college students</strong>. ADW doesn't cover all species in the world, nor does it include all the latest scientific information about organisms we describe. Though we edit our accounts for accuracy, we cannot guarantee all information in those accounts. While ADW staff and contributors provide references to books and websites that we believe are reputable, we cannot necessarily endorse the contents of references beyond our control. </p> </div> <div class="footer-links"> <ul class="unstyled"> <li><a href="https://www.umich.edu/">U-M Gateway</a> | <a href="https://lsa.umich.edu/ummz/">U-M Museum of Zoology</a></li> <li> <a href="https://lsa.umich.edu/eeb/">U-M Ecology and Evolutionary Biology</a> </li> <li> 漏 2020 Regents of the University of Michigan </li> <li><a href="/feedback/error_form/">Report Error</a> / <a href="/feedback/comment_form/">Comment</a></li> </ul> </div> <div class="thanks-links"> <p>This material is based upon work supported by the <a href="https://nsf.gov">National Science Foundation</a> Grants DRL 0089283, DRL 0628151, DUE 0633095, DRL 0918590, and DUE 1122742. Additional support has come from the Marisla Foundation, UM College of Literature, Science, and the Arts, Museum of Zoology, and Information and Technology Services. </p> <p> The ADW Team gratefully acknowledges their support. </p> </div> </div> </div> <script></script> </div> <script src="/static/js/jquery.colorbox.js"></script> <script src="/static/js/pica.information.js"></script> <script type="text/javascript"> var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www."); document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); </script> <script type="text/javascript"> try { var pageTracker = _gat._getTracker("UA-7143967-1"); pageTracker._setCustomVar(1,"author",":Limas,Brian:",3); pageTracker._setCustomVar(2,"editor",":Johansson,Carl::Pajerski,Lauren::Hammond,George::Dewey,Tanya:",3); pageTracker._setCustomVar(3,"organization",":Fresno City College:",3); pageTracker._trackPageview(); } catch(err) {} </script> <script type="text/javascript"> (function(c,l,a,r,i,t,y){ c[a]=c[a]||function(){(c[a].q=c[a].q||[]).push(arguments)}; t=l.createElement(r);t.async=1;t.src="https://www.clarity.ms/tag/"+i; y=l.getElementsByTagName(r)[0];y.parentNode.insertBefore(t,y); })(window, document, "clarity", "script", "6f4vquqfce"); </script> <script async="async" src="https://www.googletagmanager.com/gtag/js?id=G-0ZHSR6DBVK"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'G-0ZHSR6DBVK'); </script> <script type="text/javascript" src="/static/bootstrap/js/bootstrap.js"></script> <script type="text/javascript" src="/static/social-likes/social-likes.min.js"></script> <script type="text/javascript" src="/static/js/links.js"></script> </body> </html>