MANTA RAY
ESA Threatened CITES Appendix II
Using pectoral fins spreading up to 23 feet (7m) across, giant manta rays glide like underwater spaceships. Mantas have one of the largest brain-to-body size ratios in the marine world and appear to recognize themselves in mirrors, according to several studies. These animals also seem to recognize other individuals and to have preferred relationships maintained over time. Divers have observed these animals playing in their bubbles.
NOAA surveys show that manta rays are most common off northeastern Florida during April, moving north as temperatures warm to the North Carolina coast and south in the fall to the Georgia coast. In the Gulf of Mexico, they hang around the Mississippi River delta from April to June and October to November.
Individual mantas can be identified by the unique patterns on their undersides, and scientists use this fact to monitor specific populations. Staff at the Flower Garden Banks National Marine Sanctuary in the Gulf of Mexico have created a photo catalog of individuals seen there. A manta photo catalog created by biologists at Australia’s Ningaloo Reef revealed that scars originally thought to be created by predators were probably from vessel strikes. The animals bask and feed at the surface, and boat strikes are an increasing threat.
Their main threat globally is directed take for their gill rakers, used in traditional Chinese medicine, and indirect take by industrial fisheries, says Nick Farmer with NOAA Fisheries Southeast Office of Protected Resources Division. They also are affected by bycatch, entanglement, and pollution. A nursery habitat in the heavily urbanized waters off the Florida coast raises particular concern about plastics and other pollution.
この記事は DIVER Canada の Spring 2023 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、9,000 以上の雑誌や新聞にアクセスしてください。
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この記事は DIVER Canada の Spring 2023 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、9,000 以上の雑誌や新聞にアクセスしてください。
すでに購読者です? サインイン
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