{"id":231364,"date":"2026-01-07T00:42:12","date_gmt":"2026-01-07T00:42:12","guid":{"rendered":"https:\/\/www.newsbeep.com\/ie\/231364\/"},"modified":"2026-01-07T00:42:12","modified_gmt":"2026-01-07T00:42:12","slug":"researchers-extract-dna-from-25-killer-whales-off-the-coast-of-japan-and-make-crucial-new-discovery","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ie\/231364\/","title":{"rendered":"Researchers extract DNA from 25 Killer whales off the coast of Japan \u2013 and make “crucial” new discovery"},"content":{"rendered":"

Orcas off the coast of Hokkaido,\u00a0Japan, can be split into two distinct ecotypes \u2013 resident and transient \u2013 according to a new study published in\u00a0Marine Mammal Science.\u00a0<\/a><\/p>\n

Also known as killer whales,\u00a0orcas<\/a>\u00a0are currently categorised as one species (Orcinus orca). However, the distinct forms, or ecotypes, are so different that some researchers believe they might be different species.<\/p>\n

There are three known ecotypes in the North Pacific \u2013 resident, transient and offshore \u2013 each with its own genetics, appearance, language and diet. <\/p>\n

Residents eat fish, transients hunt mammals \u2013 including seals,\u00a0humpback whales<\/a>,\u00a0blue whales<\/a>\u00a0and\u00a0sperm whales<\/a>\u00a0\u2013 and offshore orcas eat fish but are also known to hunt sharks. They have been recorded killing\u00a0great whites<\/a>\u00a0and enormous\u00a0whale sharks<\/a>\u00a0by turning them belly up \u2013 to subdue them \u2013 then tearing out their liver and feasting on its nutrients.\u00a0<\/p>\n

Killer whales in the eastern North Pacific, off the coastline of Canada and Alaska, are incredibly\u00a0well-studied<\/a>\u00a0but less is known about the orcas in the western North Pacific. This new research aimed to change that by analysing the genomes of 25 individuals from around Hokkaido \u2013 the most northerly of Japan\u2019s islands.\u00a0<\/p>\n

An earlier study of these North Pacific orcas had suggested that some ate fish while others ate mammals and this new research takes that further by confirming the population can be split into resident and transient ecotypes.\u00a0<\/p>\n

\"KillerAs part of the study, researchers analysed DNA from 25 killer whales around Hokkaido island in Japan. Credit: Getty
\n\"EcotypesThis graphic shows ecotypes of killer whales around Hokkaido. The red regions in the top left map show the sea areas where we can frequently see killer whales. Credit: Momoka Suzuki<\/p>\n

Their in-depth DNA analysis also showed that resident killer whales shared the same haplotype (group of inherited genes) while the transients had eight different haplotypes making them more genetically diverse. This finding suggests that transient killer whales used Hokkaido as a refuge during the last Ice Age, the researchers say.<\/p>\n

\u201cClarifying the ecological characteristics of killer whales is crucial for achieving coexistence with them,\u201d says first author Momoka Suzuki, Kyoto University, in a\u00a0statement<\/a>.<\/p>\n

Understanding the diet and behaviour of orcas in Japanese waters gives conservationists important information that can help protect the animals from threats. \u201cThey are deeply entwined with human activities such as tourism and fisheries in Hokkaido,\u201d adds Suzuki.<\/p>\n

Shiretoko,\u00a0<\/a>a UNESCO World Heritage site in the northeast of Hokkaido, is known as one of the best killer whale watching hotspots in Japan. The scientists hope their research can help fill in the gaps about the little-studied population found here.\u00a0\u201cWe will continue to collect ecological data using a wide range of methods, including behavioural observation and genetic analysis,\u201d says Suzuki.<\/p>\n

Two killer whales ‘spy-hopping’ (looking at surroundings above the surface) off Shiretoko peninsula, Hokkaido, Japan. Credit: Getty<\/p>\n

Top image: Orcas off the coast of Hokkaido. Credit: Getty<\/p>\n

More wildlife stories from around the world<\/p>\n","protected":false},"excerpt":{"rendered":"Orcas off the coast of Hokkaido,\u00a0Japan, can be split into two distinct ecotypes \u2013 resident and transient \u2013…\n","protected":false},"author":2,"featured_media":231365,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[61,60,82,263],"class_list":{"0":"post-231364","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-wildlife","8":"tag-ie","9":"tag-ireland","10":"tag-science","11":"tag-wildlife"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/231364","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=231364"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/231364\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/231365"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=231364"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=231364"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=231364"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}