The Sea lamprey is a predator upon many commercial fish species in many lakes in the United States. They are originally from the Atlantic ocean, but through cannals came to certain lakes in the United States. The sea lamprey act like leeches in a sense, attatching themselves to their prey with their mouth and cutting into their skin with their many rows of teeth, depriving the prey of it's blood. The Sea lamprey has a total life span of about 20 years. They can produce quickly and have been a major problem for fish in certain lakes such as the Great Lakes, since they are connected to the Atlantic ocean. They are generally 13-20 inches in length, and come in colors such as black, grey, and blue. The sea lamprey has already cut back many commercial fish species and is a problem to fishermen. (1, 2, 3)
The Beluga Whales have been considered endangered since the 1990's. They are hunted in Alaska by native tribes, using their blubber for many purposes. Pollution also causes a threat to this species, especially pollution in estuaries where they spend their time hunting. The population of these whales has said to recover by some people, but studies show that it has declined and actually gotten worse. (5, 6)
The Tiger Shark is a keystone species due to the fact that it preys among certain organisms that eat seagrass. If these organisms had no predator, the seagrass in certain aquatic ecosystems would be completely comsumed, changing or destroying the ecosystem. It preys upon preys such as sea turtles and dugongs, which are major consumers of seagrass. The fact that they prey upon these certain species, makes the tiger shark an important keystone species. (7, 8)
The Killer Whale has certain adaptations for killing it's prey. This includes its sharp rows of theeth that make it easy to rip through the flesh of its prey. Another adaptation that the killer whale has, is its shape and smooth blubber that makes it easy for the whale to have agility and swim at fast speeds when it choses to. The Killer Whale has a wide variety of preys including marine mammals which their throats can swallow whole, fishes that swim near the surface, bottom-dwellers, and even other killer whales. Although the diets of killer whales vary due to their locations, they can hunt in groups or individually. (9, 10, 11)
The Southern Stringrays have many useful adaptations that protect them against predators. One of them is that the southern stingrays shape, which help them blend into their surrounding very well. They are generally flat in shape, and they don't have heads that made them obvious to predators. Their grey color also isn't very distinctable to predators, they spend much of their time buried in the sand. These adaptations make it easy for southern stingrays to hide from their predators. (12, 13, 14)