It\u2019s no secret the deep sea is home to some strange-looking animals, so might we introduce you to yet another weirdo: the seven-arm octopus, AKA \u201cthe blob octopus\u201d. This ocean giant can weigh up to 75 kilograms (165 pounds), but despite its huge size, it’s rarely been seen alive.<\/p>\n
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Now, a recent sighting by the ocean experts over at the Monterey Bay Aquarium and Research Institute<\/a> (MBARI) has yielded some incredible footage. It marks just the fourth time they\u2019ve encountered this animal in 40 years of ocean exploration.<\/p>\n It was spotted via a remote operated vehicle (ROV) known as Ventana, which was cruising in Monterey Bay as part of a research expedition last month. On that day, Senior Scientist Steven Haddock and researchers from MBARI\u2019s Biodiversity and Biooptics Team were treated to a rare sight at approximately 700 meters (2,300 feet) deep \u2013 a seven-arm octopus in all its blob-like glory.<\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0<\/p>\n Known to science as Haliphron atlanticus, these octopuses do in fact have eight arms, but they\u2019re known as seven-arm octopuses because of a curious behavior seen in the males. During mating, the male will rip off a specialized arm known as a hectocotylus to use as a tool for transferring sperm. Most of the time this arm is tucked up beneath one of its eyes, so the males look as if they only have seven arms.<\/p>\n You might wonder what the significantly larger female octopuses would have to say about this (they can reach around 4 meters [13.1 feet], the males just 21 centimeters [8 inches]). As Jack Ashby<\/a> points out in Nature\u2019s Memory<\/a>, it\u2019s often the male of the species that takes center stage in museums, and evidently this trend can bleed into species naming, too.<\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0<\/p>\n However many arms it’s packing, it\u2019s a rare and remarkable thing to see one of these octopuses alive. The media recently got very excited about the discovery of a seven-arm octopus arm on a beach in Aberdeenshire<\/a>, UK (which, to be fair, is an odd place for such an arm to turn up), but we can learn all sorts from seeing them in motion.<\/p>\n A 2017 sighting of a living seven-arm octopus led to a paper by Haddock and MBARI collaborator Henk-Jan Hoving, which was the first to reveal that seven-arm octopuses like to feed on gelatinous animals<\/a> (and may use their stingers to hunt<\/a>). That certainly seems to track in this latest footage.<\/p>\n \u201cUsing a 4K camera specially developed by MBARI engineers for deep-sea exploration, the team collected detailed observations of the animal\u2019s appearance and behavior,\u201d MBARI wrote on YouTube. \u201cThis extraordinary octopus was clutching a crimson red helmet jelly (Periphylla periphylla).\u201d<\/p>\n \u201cThis new sighting underscores the complexity of deep-sea food webs and their surprising connections.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"It\u2019s no secret the deep sea is home to some strange-looking animals, so might we introduce you to…\n","protected":false},"author":2,"featured_media":299604,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[90,56,54,55,4407],"class_list":["post-299603","post","type-post","status-publish","format-standard","has-post-thumbnail","category-wildlife","tag-science","tag-uk","tag-united-kingdom","tag-unitedkingdom","tag-wildlife"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/299603","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=299603"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/299603\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/299604"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=299603"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=299603"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=299603"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}