さて、今回のニュースは昨年11月に続いての深海魚出現のお知らせです。先日1月21日（日）、淡島近くの港で変わった形の巨大な魚がいるとの連絡があり、そこで巨大な「ラブカ」を保護しました。

ラブカとはカグラザメ目ラブカ科の魚で、サメの仲間です。ラブカは全世界の海洋に局所的に分布が見られるサメですが、通常想像されるサメとは違った点があります。

歯はフォークのような形、鰓孔が6対（通常のサメの仲間は5対）、背鰭は1つで体は細長いなどの特徴があり、これは古生代に生きたサメの祖先によく似ているのでシーラカンスと同様に「生きた化石」などと呼ばれています。

淡島ではここ10年間で2度目の保護となります。今回保護したラブカは全長160ｃｍ、体重7.5ｋｇのメスでした。生きたまま保護できたため、数時間の間は海の中を泳いでおり、当館では初めて泳いでいるラブカの姿を映像に収めることに成功しました。

ラブカは通常水深600ｍ付近で生活しているといわれていますが、水温の低下するこの時期にはこのような深海性の生物が表層近くに上がってくることがあります。そこへ風や海洋の対流の影響で海面まで上昇したと考えられますが、詳細については不明です。

淡島水族館内では、ラブカについての「パネル展示」「未公開動画」を実施していますので是非御来園下さい。

On January 21, Awashima Marine Park had a rare opportunity to closely observe a live frill shark (Chlamydoselachus anguineus). The shark was found by people enjoying fishing at a small fishery harbor close to our park. We were informed that they found a large strange shaped fish swimming inside the harbor. We dispatched our staffs immediately and they confirmed the shark as a frill shark.

The area including the Awashima Island is facing Suruga Bay. Suruga Bay has a very deep canyon quickly reaching about 2500-m depth. Thus, we occasionally have visitors from the deep sea. This is the second time we have a frill shark past ten years. The shark was 160 cm in length and 7.5 kg in weight. Frill sharks belong to the order of Chlamydoselachiformes and the family of Chlamydoselachidae. Frill sharks are found almost all oceans but live very restricted area usually 600m depth. Frill sharks look very different from ordinary sharks. They have single dorsal fin and a very long body. The shape of a tooth looks like a fork. A frill shark has six pairs of gill clefts to compare with an ordinary shark having five pairs. These characteristics are very similar to those of ancient sharks used to live in the Paleozoic era. Thus, frill sharks are considered as the living fossils.

By the time our staffs saw the frill shark, she already looked very sick or weak. Thus, we decided to bring her to our park for medical examination and care. We concerned she might have infectious disease. We introduced her into our natural open water enclosure. We provided her assist to keep water running into her gills as necessary. Many sharks need to keep swimming to get oxygen from water through gills. Fish can take water from its mouth and push water through its gills. Unfortunately, she died after few hours of our treats. During winter, as the water temperature goes down, often deep-water creatures come up to the surface layer. She might be in this case and strong wind and current push her into the harbor. However, at this moment, the truth is deep in myth.