CM – Leopard seals feed on sharks, researchers discover – Oceanographic

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A new study suggests, as a world first, that New Zealand’s leopard seals feed on sharks based on the remains of feces and scars.

Leopard seals are top predators that prey on numerous species, including pinnipeds, fish and birds . They have a circumpolar distribution, while some individuals travel further north to the continents and islands of the Southern Ocean. More and more leopard seals are sighted in New Zealand and some individuals have lived on the New Zealand coast for years.

A new study, published in Marine Science in Frontiers, found evidence of leopard seals that predated sharks from the remains of feces and scars on seal bodies. Although several nutritional studies have been conducted, none have ever found the species that predated Chondrichthyans. The study, led by Krista van der Linde of leopardseals.org, suggests that leopard seals are part of an exclusive club of sea predators that hunt sharks. As part of the study, with the help of Citizen Scientists, the researchers « recorded 39 predator observations between 1942 and 2019 and collected 127 feces (166 total records). » The study further states that « predation to Chondrichthyans was found in 23.1% of the predation observations and in 7.1% of the faeces ». The scats were taken by morphological examination and DNA sequencing.

Three main shark species were identified by the study: the elephant fish, the ghost shark and the dogfish. The study further noted that « although this is the first published record of leopard seals feeding on Chondrichthyans, the relatively high frequency of occurrence in New Zealand records and that certain individuals appear to target this type of prey, suggests that these species are found play an essential role, « or an important part of the diet of some leopard seals in this region. »

« We were overwhelmed to find sharks were on the menu, » Van der Linde told The Guardian. “But then we also discovered that elephant fish and ghost sharks were also hunted by the leopard seals. These fish have large spines to protect them from predators and, in fact, there were wounds on the leopard seal, sometimes even large spines on their faces. A leopard seal had at least 14 such wounds. ”These results also suggest that leopard seals are actively eating sharks, not just eating their remains. Faecal samples collected also showed that they make up a significant part of their diet.

As leopard seals are relatively new to New Zealand and their presence in the country is becoming more common, researchers ask themselves some important questions: Are these seals coming to New Zealand to get more food as climate change affects food sources further south? And how does this affect New Zealand’s sharks and the local food web?

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Keywords:

Leopard seal,Sharks,Seals,Mammal,Leopard seal, Sharks, Seals, Mammal,,,Sharks,leopard seal,SEAL,New Zealand,Ocean,Wildlife,Ecosystem,ghost shark,WWF,Animals,,

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