There are 2 major groups. Toothed whales include 2 families, the beaked and bottlenose whales and the sperm whale, the white whales and the narwhal. They catch fast-moving prey and they have a single blowhole and wide throat. Toothless whales, there are 3 families of baleen whales, the right whale family, the gray whale family and the Rorqual family is the most familiar of the large whales. They lack teeth but have brushlike sheets of a horny material called baleen.
They have a wide variety of preys, however they prefer to prey on stingrays (Strong, 1990). Their denticles are used to prey on the stingrays in order to facilitate their feeding. These denticles are used more as teeth than fish scales of how sharp and dangerous they are. They also prey on invertebrates, small boney fish, and other sharks as well. They travel throughout the coastal semi ocean (Carlson, 2002).
On May 3rd, Dr. Morten Tange Olsen presented to us on the seal virus epidemic that took place in 2002 and was one of the biggest virus epidemics to ever take place in the world. The virus was found in two types of seals. The first type of seal that it was found in is the harbour seal, which is found in the Northern hemisphere. The second type of seal that the virus was found in is the grey seal, which at one point was very common in Denmark but was almost driven to extinction 150 years ago due to hunting. However, the grey seal has slowly began to repopulate on Danish shores and is making a comeback.
Humans were not around at the time the monk seals arrived, and the monk seals are more commonly found in the Northwestern Hawaiian Islands that are less inhibited by people compared to the Main Hawaiian Islands with a larger human population (Lowry et al, 2011). The Hawaiian monk seal population has been in a rise and fall ever since the discovery of the monk seals by a Russian explorer in 1805. Due to its discovery, the monk seal population virtually died out by the mid 1800’s due to the commercial seal hunting and being killed for food by sailors and whalers (Lowry et al, 2011). Until the mid 1900’s, the seals were never seen and thought to be extinct because they were never seen by hunters or sailors, but the first beach count survey was taken in 1958, showing a slight recovery (Schultz et al, 2010). Another decline was also seen during the 1960’s-1970’s that showed a 75% decrease in number of monk seals seen on the Northwestern Hawaiian Islands (Gilmartin et al,
What Whale Poaching Really is By: Logan B I believe whale poaching should be outlawed around the world. Bans have warned people to stop hunting the whales but still over 2,000 whales are killed each year. In 1958, thirty eight thousand whales were killed since then, the amount of whales killed has dropped to thirty six thousand whales from that time. There are almost four whales killed each day. If someone is caught violating the laws it will result in civil penalties up to $11,000 or criminal penalties up to $100,000 plus, one year of prison time.
When local flies are living underwater, typically just after hatching and during the immature phase, fishermen should use a wet fly. Wet fishing flies are meant to go under the surface of the water. Most wet fly bait will sink on its own, quickly and effectively, but a sinker may be added to the line to increase weight if necessary. Lastly, there is the nymph-style fly fishing bait. Meant to represent the fly 's juvenile state, real-life nymphs frequently match the color and shade of the bottom of a river or lake.
This indicates feeding occurs near the surface, in midwater, and along reef edges (Júnior, et al., 2004). Endangered Species Status The National Marine Fisheries Service (NMFS) manages the sailfish under the authority of the Magnuson-Stevens Fishery Conservation and Management Act to insure the long-term sustainability of fishery stocks. Commercial vessels U.S. flagged are prohibited from selling, retaining, or purchasing sailfish. Recreational fishers must obtain a permit from NOAA fisheries for fishing in federal waters and state regulations may also apply (Susie 2009). Sailfish populations have been depleted, and don’t look like they are getting any better.
Elizabeth Miller Physical Geology Lab Environmental Issues Paper Global Warming vs Polar Bears Scientifically known as Ursus maritimus, the polar bear is a marine mammal that spends more time at sea than on land. (“Global Warming and Polar Bears”) The bears’ population is between 20,000 and 25,000 worldwide. (“Polar Bears Threatened by Global Warming, Says Bush Administration”) Stocks, or groups of polar bears, are distributed throughout the Arctic. They are known to be long-lived creatures. The ability to replace individuals is very limited and the population growth is extremely slow.
But, they all have something in common, in that they are all very interesting. Baby Sharks, Physical Appearance, and “Family Life” First of all, sharks are surprisingly not that cute as babies. Baby sharks are called pups. Pups are twice the size of your average goldfish, and have one sort-of-sharp set of teeth. Pups can be born in three ways.
For centuries, humans have hunted numerous whale species for their meat, oil, and baleen. Due to the technological advances made in the 18th and 19th century, whaling became increasingly more popular. By the 1930s, over 50,000 whales were being killed every year, and many species (such as the sperm whale) were almost hunted to extinction. Now that these species are finally making a comeback, it is pivotal that we as a society, who wants to keep our whales, make sure that we never allow whaling to get as out of hand as it was in the past. Today, whaling is still a threat, and the International Whaling Commission tries to regulate all whales killed, but there is still a lot happening under the radar.
The invertebrates that form the gray whales primary prey are restricted to shallow water environments, but global sea-level changes during the Pleistocene eliminated or reduced this critical habitat multiple times. Because the fossil record of gray whales is coincident with the onset of Northern Hemisphere glaciation, gray whales survived these massive changes by adapting their feeding habits. When continental glaciers locked up vast quantities of the earth 's water, ocean levels dropped up to 400 feet. This transformed what is now the sea bottom into wind-scoured steppes. At the height of the ice age, most of the modern gray whale food source would have been high and dry, and yet, the whales survived.
Hunting, coupled with the extensive deforestation of their habitat for farm ground, severely crippled the wood ducks population. The Migratory Bird Treaty Act allowed for the complete protection of the wood duck and placed limits on hunting the species (Bellrose 1976). Protection from hunters, conservation of remaining habitat, and the development of the wood duck nest box, led to one of the best comeback stories in North American wildlife history. By 1941, 14 states allowed the take of 1 wood duck per hunter, and by the mid 1960s, wood ducks ranked second or third in the bags of hunters from the Mississippi and
The loss of the krill herbivore would have the greatest effect on the economy. Without the krill, the sockeye salmon lose effectively their entire food supply. The sockeye salmon industry is worth $230 Billion in Alaska alone. If the sockeye salmon starve and the industry takes a huge financial hit. 8.
Endangered Native Atlantic Salmon: Salmon Presentation Project (Not a Final Draft) Salmo salar, most commonly known as Atlantic Salmon, was once native to almost every freshwater river connected to the Hudson River. Due to what people have treated salmon during their history, many species have been endangered and even extinct, this includes the Native Atlantic Salmon. When people first came to Maine, Atlantic Salmon was the main source of food to eat. The population was still very steady then, but it wasn 't until the early 1800’s that populations decreased. European colonists in the Atlantic began massive fishing for fish, and Atlantic Salmon was a common victim of these harvestings.