The bowhead whale is a black mammal that can grow as long as 60 feet. Sea World estimates that only about 8,000 of them remain. Blue whales can exceed 100 feet in length and are the largest animal in the world. According to Sea World, only 14,000 of them at the most are still around. Sperm whales have teeth, small front fins and flat heads. Their numbers are only about 200,000.
Only around 1,200 of the Hawaiian monk seals remain. These seals are native to Hawaii and can plunge 600 feet into the water to find food. Pollution and their decline at breeding beaches have limited the numbers of the Hawaiian monk seal. Caribbean monk seals are facing similar threats in their native area.
Otters are small aquatic mammals common in zoos and other wildlife establishments. They are intelligent and feature thick fur that is perfect for moving and gliding through water. While their fur is designed to help them thrive, otters have been hunted by humans who want to use it for their own purposes. Otters help limit fish populations, so their loss could be problematic in many ways.
Angel sharks look like sting rays and reside in the Atlantic Ocean, Mediterranean Sea and Black Sea. They are often captured by fisherman's nets. The coelacanth is an African fish that can grow as big as 6 feet long. Many fishermen have also captured and killed these fish. Russian sturgeons are characterized by the bony plates that cover their body for protection. Despite this protection, pollution and fishing have narrowed their numbers.
The Indus River dolphin lives in Pakistan and is limited to around 600 because of illegal killing. Ganges River dolphins and Yangtze River dolphins are also seeing their numbers dwindle. Dolphins are highly intelligent mammals, but pollution, capture and killing have made them endangered.
