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The Atlantic Bottlenose Dolphin can reach a length of up to 12 feet and a weight of 1,430 pounds. On the contrary, most specimens of the Bottlenose Dolphin are smaller, averaging about 9 feet and weighing about 500 pounds. The Bottlenose Dolphin is an inshore species. More recently, a pelagic species has been discovered. The Bottlenose Dolphin are known to ride the surf and have been seen jumping clear of the water as high as 15-20 feet. Most Bottlenose Dolphins occur in groups of several hundred individuals that usually consist of smaller groups, with no more than a dozen animals in each. Populations of these mammals inhabit the coast and inshore waters as far north as New England to southern Florida and west through the Gulf of Mexico. There is also an offshore population that lives along the edge of the continental shelf as far north as New Jersey. The animals inhabit different areas during different events in their life cycle (mating, birthing..). The coastal habitat of Bottlenose Dolphins has become hazardous to their health due to chemical pollution. Human interaction with the Dolphins is also problematic. People occasionally feed the wild animals. This occasional feeding leads the Dolphins to become habituated to human interaction. Many of those Dolphins will later get into trouble with fishhooks and fish lines.
The Atlantic Spotted Dolphin can reach a maximum length of 7.5 feet. The Spotted Dolphin closely resembles the Atlantic Bottlenose Dolphin; however, the latter tends to be more slender. As the name "Spotted Dolphin" suggests, the adult animal is dorsally marked with numerous grayish-white spots and ventrally with darker spots. The extent of its coloration changes with age. Younger animals completely lack spots. The species occurs in herds of up to several hundred individuals, with smaller groups that could include from ten to fifty animals. They are frequently seen jumping clear of the water, and riding the bow wave of moving vessels. Spotted Dolphins are usually found farther offshore than Bottlenose. This species of Dolphin is thought to inhabit a range of the western North Atlantic from Cape May, New Jersey to Panama.
The Atlantic White-sided Dolphin ranges from about 7 to 9 feet in length. This species is only found in the North Atlantic Ocean, where it ranges from Cape Cod to Greenland (some individual animals have been spotted in the Chesapeake Bay). Most sightings of this animal have occurred in waters with a temperature below 12 degrees Celsius. The Atlantic White-sided Dolphin can be seen individually or in schools of up to 500 animals. These animals may scatter or split from their school in order to feed more efficiently. They are most often observed offshore. This species can be identified by its distinct coloration. There is a narrow white patch on its side that runs down the length of its back and tail. This white patch ends abruptly with a defined yellow or tan patch. This yellow area runs up toward the dorsal ridge of the tail.
The Common Dolphin ranges in size from six to eight feet long. It is known to inhabit waters in the western North Atlantic from Venezuela to Newfoundland. This species is thought to frequently remain offshore, as opposed to Bottlenose that more often will swim inshore. Common Dolphins can be found in herds ranging from 50 to nearly 2000 animals. They are very active in the waters. Many will frequently jump clear of the water and bow ride for long periods of time. They are known to have one of the most complex coloration patterns of all cetaceans. If observed up close, one can note the distinct crisscross or hourglass pattern along the sides of the animal.
Risso's Dolphins (Gray Grampus) average about 10 feet long and 650 pounds. Surveys and reports have found this Dolphin to be the most common along the continental slope from south Cape Cod to Cape Hatteras. On the contrary, there have been some sightings in Newfoundland and the Gulf of Mexico. Risso's Dolphin may be found in herds of as little as 30 animals or as large as several hundred. In the waters, they are very acrobatic (breaching, cartwheeling, lobtailing and spyhopping). Primarily, they are squid eaters; hence, they have teeth only in their lower jaw (a characteristic common to squid eaters). If sighted, one might note the numerous scratches on the body of this species. These scratches may have resulted from encounters with other grampus or perhaps with the squid. It is also important to note its dark dorsal fin, which may be used to distinguish this marine mammal from others.
The Striped Dolphin ranges in size from six to eight feet long. Males and females become sexually mature at about 5 to 9 years of age. Those animals that are mating can be found in "mating schools," which consist of approximately 225 mammals. The other animals remain in "non-mating schools," which average about 750 dolphins. There are 3 mating seasons: January-February, May-June, and September-October. The Striped Dolphin is known for its two distinctive black stripes: one band of black beginning near the eye and extending down the side of the body to the area of the anus, and a second band of black extending from the eye to the pectoral flipper.
The Harbor Porpoise ranges in size from 4 to 6 feet long. Most specimens never reach 6 feet. Henceforth, it is known to be one of the smallest of the oceanic cetaceans. It is one of the most common inshore species seen from Cape Hatteras to Greenland. Young Harbor Porpoises are born from April through July, after a gestation period of 11 months. At birth, a calf is about 3 feet 4 inches in length. Most females bear a calf annually. Hundreds of Porpoises are entangled and drowned in gill nets that are set each year. As of today, the National Marine Fishery Service now has the Harbor Porpoise listed as a "threatened" species in U.S. waters. This species can be easily recognized by its small size, triangular dorsal fin, and flattened teeth. It is also known for making a soft puffing sound as it exhales, rather than spouting. They swim in relatively shallow waters and near the surface. They are usually observed in small groups, from singles to groups of 10 animals.Read More
The Humpback Whale is very common in the Gulf of Maine and has been seen as close as ½ mile off the shore line. The world population of Humpback Whales, which are found in almost all oceans, is estimated to be fewer than 11,000. The Humpback is less slender than the other baleen whales. Their coloration varies. However, they have long white flippers that are unmistakable characteristics. The name "Humpback" refers to the large hump on which the dorsal fin is located. Humpbacks can reach a length of 62 feet and 53 tons in weight. Calves are born at 13 to 14 feet in length after an 11.5-month gestation period. Mating and birthing take place every second or third year. Males become sexually mature when they are 38 feet long. They herd in pods of about a dozen while they are in calving grounds, but they reduce to groups of 3 or 4 during migration. At this time, the populations from the Bering Sea migrate south along the North American coastline and then west into Hawaii.
The Fin Whale inhabits all oceans, although it apparently avoids shallow waters and coastal regions. The largest populations seem to be in the Antarctic waters, although they have been observed swimming in the Gulf of Saint Lawrence. Their bodies are long and slender and they have 50 to 100 tactile hairs on the tips of the lower and upper jaws, with distinctive clumps of hairs at the tip of the lower jaw. Fin whales are dark gray to brown on their dorsal and flank regions, while their bellies are white. Fin whales can reach 88 feet in length, while females are slightly larger than males. Calves are born after an 11.5-month gestation period and weigh about 4 tons. They travel in pods of approximately 100 animals in the breeding waters, but during migration they form groups of 10 or so.
The Minke Whale is the smallest of the baleen whales with a maximum length of 28 feet. Minke Whales are recognized by their pointed snout and broad white band running across each flipper, while the dorsal fin is hook shaped and the belly is white. The overall range of this species in the western North Atlantic Ocean is from the subtropics to Northern Labrador. As sexual maturity is reached at an estimated age of 7 to 8 years, mating is thought to occur in the winter or early spring, but this has rarely been observed. The 9-foot calves are born approximately every year after 10 or 11 months of pregnancy. The Minke Whale is the most abundant baleen whale, with populations near 760,000 in the Southern Hemisphere alone. They are usually found as single individuals or as pairs or trios, while they appear to segregate by age and/or sex. A recent estimate suggests that the population of the western North Atlantic is less than 46,000.
The Right Whale is perhaps the rarest of the great whales. The North Atlantic Right Whales are distributed from Bear Island, Spitzbergen and Nordkap to Spain, Portugal, North Africa, the Carolinas, Florida and the southern area of the Gulf of Mexico. Right Whales are extremely fat and have no dorsal fin at all. They are stocky with large flippers and huge arching lips that cover and protect their delicate baleen plates. They are black with white patches and some occasional brown markings. Both the males and females are an average of 50 feet in length and 70 tons in weight. When the males reach 49 feet they are considered to be sexually mature. In females, sexual maturity is reached at 52 feet. During winter, the calves are born between 16 and 19 feet long after a gestation period of 12 months. Newborn calves stay with their mother for about a year and are weaned when the calf has grown to be about 28 feet.Read More
The Antillean Beaked Whale can reach a length of at least 22 feet. The head of this species is small and the beak, narrow. Its color is darker on the back and sides with lighter coloration in the ventral region. In adult males, two mandibular teeth erupt about one-third of the way back from the tip of the snout to the corners of the mouth. As they protrude, they fit into the grooves in the skin of the upper jaw.
When in the Atlantic, this species appears to favor warm temperate and subtropical waters. Some think it is very closely associated with the Gulf Stream. (Little knowledge and data has been recorded, because little is known about this deep-sea whale).
The Beluga ranges in size from 10 to 15 feet long. Males are usually slightly larger than females. Newborn Beluga whales are brown. As they age, they gradually lighten to slate gray. Adults are known to possess pure white color. Delphinapterus leucas literally means, "white finless dolphin." It is considered finless, because it lacks a dorsal fin. Instead, there is a narrow ridge notched laterally to form a series of small bumps.
Belugas have evolved to live in cold seas, especially along the Arctic coasts (of Greenland, Canada, Alaska and Russia). On the contrary, there are stray animals that can survive and feed in warmer waters for several years. This species possesses adaptations for life in freezing seas; the absence of a dorsal fin reduces heat loss and the top of the Beluga's head has a thick skin and thin blubber, so the whale can ram through ice to make breathing holes. Zoologists wonder what limits the Beluga to mainly Arctic waters. Perhaps it is because competition for food is too intense in southerly areas or because predatation by sharks is too dangerous.
The Blaineville's Beaked Whale averages about 15 feet long. This species has a worldwide distribution ranging from tropical waters to warm temperate waters. It is fairly easy to identify, because its lower jaw swells to a larger prominence, or rise, midway along its length. Each prominence contains one huge tooth that is between 6 and 8 inches high, almost 3 inches high and 2 inches thick. Only the tip of this tooth will protrude from its socket and it will cut through the gum tissue only in males. A female's tooth will remain inside the gum. Immature Blaineville's are toothless. Evidence shows that the function of these teeth (in most beaked whales) is fighting, not eating. Most males carry numerous scars. The size, shape and location of these scars insinuate that they are probably caused by the teeth of another male, most definitely from a fight over power or females. The jaw and teeth of this species are considered to be the most advanced of all whales in the Mesoplodon genus. Inside its jaw, there is a structure that has evolved to prevent damage during fights. This structure is a canal within a long rostrum. The rostrum has become strengthened and heavily ossified in order to withstand damage.
The Goosebeaked Whale can reach a length of 23 feet. Females are normally slightly larger than males of the same age. At birth, a calf would probably be approximately 6 feet long. As in the True's Beaked Whale, this species also has teeth located at the tip of the lower jaw. There is not a lot of information on the distribution of the Goosebeaked Whale. Unfortunately, data on the distribution must come from records on the stranded specimens. They seem to be primarily tropical, however they may venture into temperate waters during the summer months. They have been reported from Massachusetts to Florida and the West Indies. This species has been observed in tight schools of 3 to 10 animals. It is rarely observed at sea and seems hesitant to approach boats.
The Pilot Whale averages about 13 feet and 1,800 pounds. Populations of Pilot Whales are usually determined by the location of schools of squid, their primary food. Many squid migrate toward inshore Newfoundland waters during summer and early autumn; most Pilot Whales will follow. Many can be found in these waters from late June to early November. Pilot Whales usually spend winters in offshore waters. This species is abundant and continuous throughout cold temperate waters of the North Atlantic. In the western North Atlantic, populations range from North Carolina to Greenland. Mating season is at its peak in spring and early summer. Many calves are born during late summer after a gestation period of 16 months. Females reach sexual maturity at about 6 years of age, while in males it does not occur until 12 years of age. Pilot Whales do not ride the bow waves, however lobtailing (slapping the water with the tail) is common. Unfortunately, Pilot Whales tend to strand both individually and in mass herds.
The Pygmy Sperm Whale averages about 10 feet long and 800 pounds (in a full-grown adult whale). According to sightings and records, it is thought that Pygmy Sperm Whales have been found as far north as Halifax, Nova Scotia and as far south as Cuba. They are often observed bobbing quietly at the surface of the water. If startled while in this position, they may defecate, emitting a cloud of reddish brown feces into the water. Beached Pygmy Sperm Whales have also been observed to defecate a fine chocolate-like feces. Some photographs of this species show a light crescent shape at the exact place where a larger fish may have a gill slit. In this marine mammal it is often referred to as a false gill. A small dorsal fin is located toward the rear of its body. Its head only takes up about 1/7 of its total body length. It is also characterized by an under-slung lower jaw, located well behind the tip of the snout. These last two characteristics are similar to a shark's appearance and are thought to be protection against actual sharks.
The Sperm Whale is the largest of the toothed whales. Ironically, it only has teeth in its lower jaw. A male can reach up to 60 feet, while the females will only grow approximately 15-38 feet. Sperm Whales possess a single blowhole located left of its midline and far forward on its head. Its head may take up from ½ to 1/3 of its total body length. The dorsal fin is only a low hump followed by a series of crenelations along the back and tail. Their skin is usually wrinkled. As a Sperm Whale begins a deep dive, it throws its large triangular flukes high into the air. This species of whale has been named for its high quality oil located inside its head, called spermaceti. This spermaceti probably acts as a sound guide for locating food (squid). It may be a type of echolocation. Sperm Whales occur in groups separated by sex, age and reproductive state. Females and young usually remain within warm waters, while individual males range into colder waters. The females will generally inhabit waters between latitude 30 and 50 degrees north. Males may swim as far north as Greenland and Iceland. Sperm Whales have the slowest reproductive rate of all whales. Gestation lasts for about 15 months and a calf will nurse for approximately 2 years. A female will probably not become pregnant again until 9 months after weaning. Hence, the entire process occurs only about every 4 years.
The True's Beaked Whale can reach a length of 17 feet. This species is thought to inhabit primarily temperate waters. They have been reported from Cape Breton Island, Nova Scotia to as far south as Flagler Beach, Florida. The teeth of an adult male True's Beaked Whale are visible near the tip of the jaw. When observing the head of a True's, one should note the small head, pronounced beak, position of blowhole in the indentation behind the forehead and the two V-shaped throat grooves that are characteristic of Beaked Whales. This species tends to be black to dark gray on the back, lighter gray on the sides and white on the belly. Frequently, the body is covered with light spots or splotches. True's Beaked Whales may be confused with the Goosebeaked Whale. In order to distinguish the two mammals, one should note that the Goosebeaked Whale could reach a much larger length.Read More
In New Jersey, the seals most commonly seen in and around our beaches are Harbor, Harp, Gray, Hooded and an occasional Ringed Seal. They most often strand between November and May when our waters are the coldest and return to the north during the summer months. All pinnipeds (seals, walrus and sea lions) are adapted to life in the sea; however they come ashore to rest, breed and molt. Fur seals and sea lions (having external ear pinna (flaps) have upright mobility on land and are able to walk using all four limbs. In contrast, true seals (lacking external ear pinna) have fairly restricted movement out of water, using their clawed fore flippers to wriggle their bodies across the land. Less nomadic than other pinnipeds, Harbor Seals are often seen close to shore “hauled out” on a sandbar or jetty.
The California Sea Lion is perhaps the most familiar of the pinnipeds. They breed on San Nicholas, San Miguel, San Clemente, and Santa Barbara Islands in southern California waters. Females give birth about 4 or 5 days after coming ashore in May and June. The pups are nursed for about 8 days, before their mothers go into the open water to feed for approximately two days. Immature adult females molt in August and September, while adult males molt from November through February. Male Sea Lions grow to 7.5 feet in length, while the females grow to 6 feet. Newborn pups average 3.5 feet in length. When the pups are 3 months old, they weigh 16 to 18 kg. The pups are dark brown at birth and soon molt into a lighter brown coat within the first month. At 5 to 6 months of age, they molt again, but this time their purlage becomes blonde to light brown. Males develop a forehead and broad chest when they enter puberty. This distinct forehead is called the "sagittal crest." In the past the MMSC has had one Sea Loin stranding.
Unlike their name, Grey Seals can actually have a wide variety of coat colors and patterns. The females are usually lighter in appearance, especially around the neck, and have irregular patches of black or dark brown on a lighter background. The males usually have lighter spots on a dark brown, black, or gray background. However, there is much variation within the species. In fact, the immature animals may have spotting that resembles the coat of a Harbor Seal.
Grey Seals live primarily in the northern North Atlantic in sub-arctic and temperate waters. They are divided into three groups, including the western, eastern and Baltic groups. On average, the males of this species can reach 8 feet in length and up to 800 pounds, while the female is much smaller at only 7 feet in length and weighing 550 pounds. Adults may live to be over 40 years old, but the average life span is closer to 35 years, with the male's life-span being somewhat shorter at 30 years.
In order to distinguish this species from others, it helps to look at the face. The nose of the Grey Seal is often called a "Roman nose" or "horse head" due to its prominence and squared-off appearance. Also, since they are well separated, the nostrils look as if they form a "W," as opposed to the "V" or heart-shaped nostrils of the Harbor Seal. Moreover, the eyes are set closer to the ear on the Grey Seal rather than farther forward like those of the Harbor Seal.
The breeding season of the Grey Seal runs from late September through early March. During this time, the pups are born primarily on rocky mainland shores. After birth, the pups nurse for an average of 17 days, during which time they gain about 4 pounds per day. This is due to the 60 percent fat content of their mother's milk. This weight gain is necessary, because they spend the next 1 to 4 weeks fasting before they begin feeding at sea. During this time, they molt and begin acquiring the spotted coloration of the adults. Once weaned, these pups are known to wander great distances, including one tagged pup that was recovered in Barnegat Light, New Jersey.
The diet of the Grey Seal is quite varied, including such fish as capelin, flounder, cod, and salmon, as well as shrimp and crabs. An adult is thought to eat 2-3% of its body weight a day, which is considered to have a considerable impact on certain fisheries.
The Harbor Seal has a vast range, resulting in wide variations in appearance, physiology and behavior. There are at least 6,000 Harbor Seals in Maine waters, and can normally be found in New Jersey waters from December through March. They bask on near-shore ledges and small islands in bays, harbors, and estuaries in the Gulf of Maine, and often come very close to boats, due to their apparent curiosity for human activity.
They have a distinctive dog-like profile with eyes set halfway between the ear and the tip of the nose. From the front, the nostrils appear to have a "V" or heart shape. Their coats vary from light gray or tan to brown and red, with black or light spots. The coat often looks dark when wet, but can be very light when dry. The males are about 6 feet long and can weigh up to 250 pounds, which is consistently larger than the females that only reach about 5 feet in length.
Unlike many seal species, the Harbor Seal pup has a coat that closely resembles the adult coat. Some have a longer, softer white or gray coat (lanugo) when born, but they shed that coat within about 10 days. These pups are born from late April to mid-June and weigh about 21 pounds with a length of about 2.5 feet. These pups are very precocious and can swim almost immediately after birth. During the first week of life, the pup often rides on its mother's back while she swims. The pups are weaned after about 30 days.
Wild Harbor Seals probably consume 6 to 8 percent of their body weight in food per day, depending on the nutritional value of the food being eaten. Their diet varies greatly depending on location, and includes a wide variety of fish, cephalopods and crustaceans. Their average life span is around 25 years, although some have lived for over 30 years. However, males tend to live shorter lives, probably due to the added physical stress of fighting during breeding season.
Harp Seals get their name from the dark harp-shaped pattern that can be found on the back of the adult coat, and this pattern is most pronounced on males. They are similar in body shape to the Harbor Seal, however they are significantly larger. The Harp Seal is found most commonly in the North Atlantic and Arctic Oceans and north of Russia, but it has been known to wander as far south as Virginia.
Newborn pups are pure white, as is often seen in pictures and on posters. This white coat is replaced by a spotted coat, similar to Harbor Seals, that will eventually show the harp-shaped pattern of the adults. The pups molt this white coat within three to four weeks after being born and before they begin swimming.
Two hundred years ago, there were up to thirty-five million Harp Seals living in the northern seas, but the harvesting of pups has caused that number to drop by more than 90 percent. The pups were clubbed on the ice for their pure white coats in the past, but the Fisheries Board of Canada and the International Commission of North Atlantic Fisheries (ICNAF) have since put restrictions on this harvesting in order to protect the stocks.
The newborn pups weigh about 25 pounds, but the adults can weigh up to 400 pounds and reach 6 feet in length. They gain this weight by feeding on capelin, herring, cod, and groundfish, as well as planktonic crustaceans, such as shrimp.
Typically, this species can be found breeding on heavy pack ice that drifts throughout the northernmost Atlantic Ocean. They also spend time off Labrador and northeastern Newfoundland. However, they are known to wander out of range often, and as far south as New England. They are not common compared to other species, and not as well understood.
The Hooded Seal gets its name from the enlarged nasal cavity of the adult male. This nasal cavity can be enlarged to twice the size of a football when the animal is angered, and forms a hood running from just behind the eyes to the upper lip. They also have an inflatable nasal membrane that can be inflated through the nostril to form a red balloon-like sac.
The pups are born from mid-March to mid-April and only nurse for about 4 days. The short nursing period means that the pups gain weight 2.5 to 6 times faster than any other phocid pups. This is possible because milk is 60 percent fat and has the lowest percentage of protein of any mammalian milk. These newborn pups are called "bluebacks" because of the coloration of their fur. The back of the pup is slate blue and the belly is light gray, while the face is black. Their beautiful coats are one of the reasons for their continued harvest in certain parts of the world. The pups are about 3.5 feet long (107 cm) and weigh about 51 pounds (23 kg) when born.
As adults, the males may reach 9 feet (274 cm) and 900 pounds (408 kg), while the females grow to about 7 feet (213 cm) and weigh approximately 670 pounds (303 kg). The adults are mature at 4 to 6 years of age and may live a total of 20 years. The adults are also harvested in some areas for their pelts, but also for their meat and oil.
Hooded Seals eat a wide variety of food items, including redfish, Greenland turbot, octopus, squid, herring, capelin, cod, shrimp, and mussels.
The Green Turtle ranges from Massachusetts to Argentina. In the United States, nests have been found in the Virgin Islands, Puerto Rico, and along the east coast of Florida. This species occupies three habitats: high-energy oceanic beaches, pelagic waters, and shallow feeding grounds in protected waters. Females deposit eggs on the high-energy beaches. Hatchlings leave the beaches and head for the open ocean. Once the turtle's carapace has reached the length of approximately 20-25 cm, it will leave the pelagic waters and move to the feeding grounds and protected waters. Their diet primarily consists of marine grasses. Sometimes, they will feed on jellyfish, mollusks or crustaceans. This species has a carapace color of brown to olive.
Ranges from Bermuda to Nova Scotia. It appears to be primarily distributed in warmer waters. It seems that breeding occurs along the coast of Florida, and on the beaches of the Keys. However, there is a lack of data on the exact location, because many people confuse the Ridley with the Loggerhead. On the contrary, this species has been observed coming on the beach of the Florida Keys to lay eggs in the months of December, January, and February. They generally feed on crabs. It is thought to be one of the smallest Atlantic sea turtles. Its carapace will usually range between 19 and 27 inches long. The carapace, the head, and the limbs are usually gray in coloration.
Can reach from 700 to 1600 pounds. Its carapace ranges in size from 47 to 96 inches long. This species is easily distinguished from all other sea turtles. It has a smooth, scaleless black skin on its back. Seven narrow ridges extend down the length of this carapace. Leatherbacks are thought to be primarily a pelagic species. However, some individuals will venture into shallow waters from time to time. Their distribution is worldwide.
This species has an extraordinary swimming ability. Their nesting behavior is similar to that of other sea turtles (selecting a suitable site, egg chamber excavation, oviposition, and nest filling). Traces of jellyfish, plants, and animals have been found in the stomachs of Leatherbacks.
1000 pounds. Its carapace (upper shell) ranges in size from 28 to 83 inches long. The carapace is reddish brown, and sometimes tinged with olive. The scutes are often bordered with yellow coloration. The shell is an elongated heart shape that is slightly concaved in front and over the shoulder. This species is fairly large, next in size to a Leatherback. The Loggerhead Turtle is a confirmed wanderer. It will enter streams, coastal bays, or creeks. In the western Atlantic Ocean, it ranges from Argentina to Nova Scotia.
While in the open sea, this species will often spend a lot of time floating on the surface of the water (sometimes sleeping). From April to August, the Loggerhead nests on the coast of the southern United States from Virginia to Florida. June is the month when nesting is at its peak. The nest is dug with the hind feet of the female to a depth of approximately 18 to 26 inches and a diameter of 10 inches. The incubation period ranges from 31 to 65 days. This turtle, after hatched and grown, will feed primarily on fish, crabs, oysters, jellyfish and sponges. It is a carnivore.Read More