![\"\"](\"http:\/\/blogs.oregonstate.edu\/gemmlab\/files\/2017\/02\/EM_0706.jpg\")
<\/a>Last year at this time we were aboard a research vessel in New Zealand<\/a> surveying for blue whales and collecting a myriad of biological data<\/a> to try and glean some insight into their lives. This winter I am processing those data and conducting a literature review to get a firm grasp on what others have found before about blue whale foraging and bioenergetics. On any given Tuesday morning Leigh<\/a> and I can be found musing about the mechanics of a baleen whale jaw, about what oceanographic boundaries in the water column might be meaningful to a blue whale, about how we might quantify the energy expenditure of a foraging whale. Here are some of those musings.<\/p>\n Humans are, for the most part, terrestrial creatures. Even those of us that would prefer to spend most of our time near, on, or in the water are limited in what we can observe of marine life. Much of the early data that was collected on blue whales came from whaling catches. Observations of anatomy and morphology were made once the whales were killed and taken out of their marine environment. This was not long ago\u2014Soviet whaling continued into the 1970\u2019s in New Zealand [3]. Because baleen whales are long lived (exact age unknown for blue whales but a bowhead whale was estimated to be at least 150 years old [4]) it is entirely possible that blue whales living today remember being hunted by whalers. Observing whales in their natural state is not easy, particularly post-commercial whaling when they are few and far between.<\/p>\n Yet, where there is a challenge, clever people develop creative approaches and new technologies, leading to new insights. High-quality cameras have allowed scientists to photograph whales for individual identification\u2014a valuable first step in figuring out how many there are and where they go [5]. Satellite tags have allowed scientists to track the movement of blue whales in the North Pacific and Indian Oceans, a first step in learning where these whales might go to breed. However, no blue whale breeding ground has definitively been discovered yet…<\/p>\n What does a whale do when it is below the surface, out of sight of our terrestrial eyes? A study from 1986 that attempted to calculate the prey demands of a whale assumed that whenever a whale was submerged, it was feeding [6]. A big assumption, but a starting place without any dive data. By 2002, tags equipped with time-depth recorders (TDR) had already revealed that blue whales make dives of variable depths and shapes [7]. But, what determines a whale\u2019s path underwater, where they must conserve as much oxygen as they can while finding and exploiting patches of prey? The advent of digital acoustic recording tags (DTAGs) in the early 2000s have allowed scientists to measure the fine-scale movements of whales in three dimensions [8]. These tags can capture the kinematic signatures (based on pitch, roll, and yaw) of lunge-feeding events below the surface. And with the addition of echosounder technology that allows us to map the prey field, we can now link feeding events with characteristics of the prey present in the area [9]. With this progression of technology, curiosity and insight we now know that blue whales are not indiscriminate grazers, but instead pass up small patches of krill in favor of large, dense aggregations where they will get the most energetic bang for their buck.<\/p>\n The advent of unmanned aerial systems (UAS, a.k.a. \u201cdrones\u201d) have provided yet another unique perspective on the lives of these whales. In 2016, our New Zealand blue whale team recorded nursing behavior between a mother and calf<\/a>. In 2017, we were able to capture surface lunge feeding behavior<\/a> from an aerial perspective, both for the first time.<\/p>\n Through innovative approaches, we are beginning to understand the lives of these mysterious giants. As is true for many things, the more we learn, the more questions we have. Through the GEMM Lab\u2019s blue whale project, we have determined that a unique population of blue whales occupies the South Taranaki Bight region of New Zealand year-round; they do not simply migrate through as their current threat classification status indicates [10]. But what are their distribution patterns? Can we predict when and where whales are most likely to be in the South Taranaki Bight? Does this population have a different foraging strategy than their Californian, Chilean, or Antarctic counterparts? These are the things we are working on unraveling, and that will aid in their conservation. In the meantime, I\u2019ll keep musing about what we don\u2019t know, and remember to keep marveling at what we do know about the largest creatures on earth.<\/p>\n References:<\/p>\n By Dawn Barlow, MSc student, Department of Fisheries and Wildlife A few weeks ago, my labmate Dom\u2019s blog reminded me that it is important to step back from the data and appreciate the magnificence of the animals we study from time to time. I have the privilege of studying the largest creatures on the planet. … Continue reading With new approaches come new insights: What we do and don\u2019t know about blue whales<\/span><\/a><\/p>\n","protected":false},"author":8072,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[712807],"tags":[712808,712899,677522,513,200562,5],"class_list":["post-1862","post","type-post","status-publish","format-standard","hentry","category-new-zealand-blue-whales","tag-blue-whale","tag-dawn-barlow","tag-foraging-ecology","tag-marine-mammals","tag-new-zealand","tag-science"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/posts\/1862","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/users\/8072"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/comments?post=1862"}],"version-history":[{"count":5,"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/posts\/1862\/revisions"}],"predecessor-version":[{"id":1873,"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/posts\/1862\/revisions\/1873"}],"wp:attachment":[{"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/media?parent=1862"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/categories?post=1862"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.oregonstate.edu\/gemmlab\/wp-json\/wp\/v2\/tags?post=1862"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"\"](\"http:\/\/blogs.oregonstate.edu\/gemmlab\/files\/2018\/02\/BW-and-RHIB-e1517899635531.png\")
<\/a>![\"\"](\"http:\/\/blogs.oregonstate.edu\/gemmlab\/files\/2017\/02\/EM_0425-e1517899776329.jpg\")
<\/a>![\"\"](\"http:\/\/blogs.oregonstate.edu\/gemmlab\/files\/2018\/02\/lunge2-e1517899825463.jpg\")
<\/a>A blue whale lunges on an aggregation of krill. UAS piloted by Todd Chandler.<\/span><\/p>\n![\"\"](\"http:\/\/blogs.oregonstate.edu\/gemmlab\/files\/2018\/02\/EM_0476s-e1517900239250.jpg\")
<\/a>\n