{"id":10260,"date":"2024-11-04T15:13:04","date_gmt":"2024-11-04T15:13:04","guid":{"rendered":"https:\/\/www.birds.cornell.edu\/ccb\/?p=10260"},"modified":"2025-05-12T13:22:17","modified_gmt":"2025-05-12T13:22:17","slug":"bowhead-whale-census","status":"publish","type":"post","link":"https:\/\/www.birds.cornell.edu\/ccb\/bowhead-whale-census\/","title":{"rendered":"Bowhead Whale Census"},"content":{"rendered":"\n

Visual and acoustic monitoring to estimate the migrating whale population off the Alaskan coast<\/p>\n\n\n\n

<\/p>\n\n\n\n

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\u00a9 Yang Center & NOAA<\/figcaption><\/figure>\n\n\n\n

The ice-based bowhead whale census, initiated by NOAA in 1978 following the IWC\u2019s 1977 moratorium on whaling, aims to monitor the migrating Bering-Chukchi-Beaufort population off Utqia\u0121vik (Point Barrow, Alaska) to establish subsistence hunting quotas. Early counts estimated fewer than 5<\/ins>,000 whales, prompting detailed monitoring to improve accuracy and enact required protections.<\/p>\n\n\n\n

The census, a collaboration between I\u00f1upiat, researchers and federal agencies funded by the local community of North Slope Borough, typically runs from April to late May, covering most of the bowhead migration period. <\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Ice-based observers use binoculars and a theodolite to track and record whale positions, speed, and distribution, ensuring sighting accuracy and avoiding duplicates. Every decade, the IWC requires an updated population estimate.<\/p>\n\n\n\n

\n

In 1984, the census expanded to include acoustic data collection. Hydrophones are placed in the water along the ice edge, enabling 24\/7 monitoring used to estimate the number of whales within and beyond the area covered by the visual range (a semicircle from the ice\u2019s edge with a 4 km radius), improving the accuracy of the overall population accuracy. Read more about Density Estimation<\/a>.<\/p>\n<\/div>

\"\"<\/figure><\/div>\n\n\n\n

A comprehensive census from 2009 to 2011, combining visual, acoustic, and aerial methods, produced a 2011 estimate of 16,892 whales with an annual growth rate of about 3.7%, reflecting a healthy, growing population. This outcome also protects I\u00f1upiat food sustainability and cultural sovereignty. The next census is in the Spring of 2025.<\/p>\n\n\n\n

\"\"
Spectrogram (above) and audio (below) of a bowhead whale song from 2010 (with beard seals in the back)<\/figcaption><\/figure>\n\n\n\n
<\/div>\n\n\n\n
\n
\n
\n

Researchers<\/h2>\n\n\n\n

Chris Clark, Ph.D<\/a>
Holger Klinck, Ph.D<\/a>
L\u00e9a Bouffaut, Ph.D.<\/a>
Irin Tolkova, Ph.D.<\/a><\/p>\n<\/div>\n<\/div>\n\n\n\n

\n
\n

Collaborators<\/h2>\n\n\n\n

J. Craig George
Judy Zeh
Geof Givens, Ph.D.
Robert Suydam
John J. Citta<\/p>\n<\/div>\n<\/div>\n\n\n\n

\n
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Funders<\/h2>\n\n\n\n

North Slope Borough<\/a><\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

Visual and acoustic monitoring to estimate the migrating whale population off the Alaskan coast.<\/p>\n","protected":false},"author":11,"featured_media":10329,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_birdpress_hero_toggle":false,"_birdpress_hero_type":"image","_birdpress_hero_image_type":"image","_birdpress_hero_style":"two-column","_birdpress_hero_ratio":"","_birdpress_hero_h1":"","_birdpress_hero_media_id":9966,"_birdpress_hero_media_array_id":[],"_birdpress_hero_media_array":[],"_birdpress_hero_media":0,"_birdpress_hero_video_id":0,"_birdpress_hero_video":0,"_birdpress_hero_youtube":"","_birdpress_hero_content":true,"_birdpress_hero_byline":"Dr. Connor Wood and ","_birdpress_hero_byline_bottom":"","_birdpress_hero_button_link":"","_birdpress_hero_button_text":"","_birdpress_hero_button_color":"","_birdpress_hero_date":false,"original_guid":"","_birdpress_hide_search":false,"_birdpress_page_width":"","_birdpress_global_cta":false,"_birdpress_widget_sidebar":"","_birdpress_next_article":0,"_birdpress_next_article_title":"","_birdpress_prev_article":0,"_birdpress_prev_article_title":"","_birdpress_sub_navigation_id":0,"_birdpress_sub_navigation":"","_birdpress_sub_navigation_title":false,"_birdpress_anchor_navigation_id":0,"_birdpress_anchor_navigation":"","_birdpress_postType":"both","_birdpress_categoryID":0,"_birdpress_tagID":0,"_birdpress_parentPostID":0,"_birdpress_parentPostTitle":"","_birdpress_menuID":0,"_birdpress_menuName":"","_birdpress_listHeader":"","_birdpress_listLayout":"card-display","_birdpress_listColumns":"","_birdpress_maxItems":12,"_birdpress_listPaginate":true,"_birdpress_displaySort":true,"_birdpress_sortOrder":"DESC","_birdpress_sortBy":"date","_birdpress_listID":"","_birdpress_listClass":"","_birdpress_displayImages":true,"_birdpress_displayCaptions":false,"_birdpress_displayExcerpts":false,"_birdpress_attTop":"","_birdpress_attBottom":"","_birdpress_showLogos":false,"_birdpress_post_logo":0,"footnotes":""},"categories":[31,79,85,30,1],"tags":[],"content-format":[],"class_list":["post-10260","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-aquatic","category-mammals","category-north-central-america","category-research","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/posts\/10260","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/comments?post=10260"}],"version-history":[{"count":0,"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/posts\/10260\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/media\/10329"}],"wp:attachment":[{"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/media?parent=10260"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/categories?post=10260"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/tags?post=10260"},{"taxonomy":"content-format","embeddable":true,"href":"https:\/\/www.birds.cornell.edu\/ccb\/wp-json\/wp\/v2\/content-format?post=10260"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}