LEARN MORE ABOUT MARINE LIFE
Writing a paper for school? Need more in depth info on marine life?
Helping marine animals like Winter may be easier than you think! Following these simple tips is a great way to start:
- The Atlantic Bottlenose dolphin (Tursiops truncatus) may grow to be 7-10 feet long and weigh between 300-500 pounds
- In the Mediterranean, the bottlenose dolphin can grow to 12 feet or more
- The calf is usually 28 to 36 inches long and weighs 25 to 40 pounds at birth
- Bottlenose dolphins inhabit temperate and tropical waters
- In North America, the bottlenose dolphins is found along both coasts of the United States
- In the Atlantic, it is the most common dolphin species along the eastern coast from Cape Cod through the Gulf of Mexico.
- There are two forms (ecotypes) of the bottlenose dolphin. The coastal or inshore form frequent harbors, bays, lagoons and estuaries.
- The potential life span is as long as 35-50 years
- It is generally accepted that female dolphins tend to live longer than male dolphins
- Age is determined by examining a sliced section of a tooth and counting the growth layers much like you would count the growth rings in a tree
- The gestation period for bottlenose dolphins is between 11 and 12 months
- Dolphins are usually found in pods or "schools"
- Dolphins establish dominance with threatening postures and gestures such as smacking their tails on the water, jaw snapping, raking, and also by physical fighting
- Dolphins sometimes jump out of the water and land on their backs or sides in a behavior called a breach
- Dolphins communicate through clicks and sounds similar to moans or whistles
There are 5 species of sea turtles found in the Gulf of Mexico:
Green Sea Turtle (Chelonia mydas) is found throughout the world's tropical oceans. The Atlantic green sea turtle has important nesting and foraging grounds on the Atlantic coasts of Costa Rica and throughout the Caribbean. The southern coasts of Florida have only recently become an important nesting ground for green sea turtles. Additional rookeries can also be found in Australia and parts of Southeast Asia. Florida's east and west coasts also serve as important developmental habitats for juvenile green sea turtles. In these waters, green sea turtles can regularly be seen darting in and out of sea grass beds. The Pacific green sea turtle (Chelonia mydas agassizi) ranges on the Pacific Coast of the Americas from southern California to Chile. Important nesting areas for this sub-species can be found in Mexico and Costa Rica.
- The green sea turtle is the largest of the hard-shelled turtles, with an average size of 300 to 500 lbs.
- The head of the green sea turtle is small compared to its body size and its jaws have a characteristic serration.
- The green sea turtle uses its serrated jaw to forage on sea grasses and algae.
- Foraging green sea turtles are important to the health of sea grass beds, which are developmental habitats for large numbers of fish species.
- The green sea turtle gets its name from the green coloration of its muscle, which is eaten by people throughout its range.
- To early European explorers, green sea turtles were important sources of protein because the turtles were easy to catch and could be kept alive with little care during long voyages.
- The Pacific green sea turtles or black turtles are genetically similar to the Atlantic green sea turtle; however, their coloration is darker and they are smaller than the Atlantic green sea turtle.
Loggerhead Sea Turtle (Caretta caretta) is found in every ocean throughout the world. They are typically subtropical in nature, nesting farther from the equator than any other species. The Atlantic Loggerhead is found in great numbers feeding along the inshore and coastal water of the Gulf of Mexico, the Florida Keys and along the eastern seaboard as far north as New England. The Atlantic Loggerhead is also found in open water of the Mediterranean, along the west coast of Africa, in the Caribbean and along the coasts of Central and South America. Nesting by the Atlantic Loggerhead is highest on beaches of the southeastern United States, with close to 90% of that nesting occurring in Florida. Important nesting of the Loggerhead also occurs in the Mediterranean countries of Greece, Turkey, and Israel.
The Pacific Loggerhead (Caretta caretta gigas) is found in the temperate waters of both the Pacific and Indian Oceans. Like the Atlantic Loggerhead, the Pacific Loggerhead is found feeding in coastal, near-shore areas along the western coasts of the Americas, around Australia, and in the Middle East. The dividing line between the two sub-species of the loggerhead appears to be South America. The most important nesting grounds for the Pacific Loggerhead is on the Island of Masirah in Oman. This population of nesting turtles exceeds that of the nesting populations along the southeastern United States. Important nesting grounds are also observed in Japan, Australia and China.
- The Loggerhead is a large reddish-brown turtle, reaching the size of 200 to 300 lbs. Male loggerheads, as with all species of sea turtle, have a tail that extends nearly a foot past their shell.
- The Loggerhead is distinguished from other species of sea turtle by having a teardrop-shaped shell or "carapace".
- The name loggerhead is derived from the turtle's large head and jaws, which it uses to crush its favorite food items: crabs, clams and conchs.
- The loggerhead is the only species of turtle to nest exclusively at night.
- The primary threats to the loggerhead are loss of nesting habitat to beachfront development and associated artificial lighting, shrimping, long line fisheries, entanglements, pollution, and being hit by boats.
Hawksbill Sea Turtles (Eretmochelys imbricata) are found in the tropical waters of the Atlantic, Pacific and Indian Oceans. Nesting occurs on small islands adjacent to feeding grounds, which are typically associated with coral reefs.
- Hawksbills are small sea turtles, ranging in size from 100 to 120 lbs.
- Hawksbills are unlike other species of sea turtle in that they generally do not travel great distances between feeding and nesting areas.
- Hawksbills get their name from their bird-like jaw, which they use to probe the crevices of coral reefs in search of their favorite food, sponges.
- Hawksbills are endangered because their scutes are a primary source of tortoise shell material, used in the manufacture of jewelry and other ornamental items.
Kemp's Ridley Sea Turtles (Lepidochelys kempi) are primarily confined to the Gulf of Mexico and the eastern seaboard of the United States as far north as New England. Adult Kemp's ridleys can be found in the Gulf of Mexico feeding on the productive coastal waters from Texas to Florida. Juvenile Kemp's ridleys can also be found in these productive waters; however, many travel north along the eastern seaboard of the United States. The primary nesting ground for the Kemp's ridley is located at Rancho Nuevo, on Mexico's east coast.
- The Kemp's ridley is the smallest of all the sea turtles ranging in size from 80 to 120 lbs.
- Kemp's ridley sea turtles are fast-swimming turtles that feed primarily on crabs.
- The carapace of a Kemp's ridley is distinguished from other species of sea turtle by its circular shape.
- Kemp's ridley and olive ridley sea turtles are the only two species of sea turtle to nest in large groups all at once. This type of mass nesting is referred to as an "arribada". In the Kemp's ridley, these arribadas are no longer observed due to severe reduction in this species' population size.
- Kemp's ridleys are the only species of sea turtle to nest exclusively during the daytime.
- Kemp's ridleys are the most endangered species of sea turtle. Because of their daytime mass nesting, populations of Kemp's ridley females and the eggs were nearly wiped out by poachers in only a few decades.
Leatherback Sea Turtle (Dermochelys coriacea) is found throughout the world in all oceans. Leatherbacks are found in open waters as far north as Alaska. Leatherback nesting occurs primarily in tropical locations such as New Guinea, Indonesia, Central America, Costa Rica, French Guiana and the southern Pacific coast of Mexico.
- The leatherback is the largest species of sea turtle, with an average weight of 1300 lbs.
- The name leatherback is derived from the turtle's leathery shell. Leatherbacks do not have a hard shell and are classified separately from other sea turtle species.
- In addition to being soft, the shell of the leatherback has 7 longitudinal ridges. These enable the turtle's adaptations to deep diving and constant swimming.
- Leatherbacks are able to tolerate colder temperatures than other species by using their large size to generate heat.
- Leatherbacks deposit more clutches per individual than other species of sea turtle, depositing between 50 and 120 eggs per clutch. A large number of these eggs are infertile eggs. It is not known why female leatherbacks lay these infertile eggs.
- Leatherbacks are critically endangered…..especially in the Pacific Ocean where the long line fisheries for swordfish and tuna entangle and kill thousands of migrating leatherbacks each year.
- The combination of long line fisheries and poor conservation techniques has led to the near extinction of leatherbacks in the Pacific.
- Leatherback nesting is on the increase in Florida with an average of 50 nests laid on Florida's east coast each year.
North American River Otter
North American River Otters (Lontra canadensis) are fresh water animals and can be found throughout all of North America in rivers, streams, lakes and ponds. They are in the family Mustilidae, which also includes ferrets, skunks, weasels, and sea otters. North American river otters are not endangered and may even be considered a nuisance animal in some states where humans have encroached on their natural habitat. Today, river otters are seen more frequently in residential neighborhoods and other populated areas.
Adult river otters are basically solitary animals. There is not a strong bond between a male and a female, except for several months during the mating season. The basic family group consists of a female and her young; however, such families break up before the female gives birth again. Male river otters may or may not take part in the family group. What is interpreted as "play" behavior among otter pups is actually adaptive behavior that reinforces social bonds and encourages young river otters to practice their hunting and fishing skills.
The peak mating session for river otters is in March and April. During this time, river otters will travel more often and are more territorial. The total gestation period for a female otter is from 9.5 to 10 months which includes a period in which the embryo remains undeveloped. This holding period is called delayed implantation and it assures that the pup is born during the best time of the year for survival and allows the female to get into good physical condition. A female river otter may bear a litter each year. The average litter of river otters is two to four pups. Female otters will nurse their young for three to four months before they are weaned onto solid food.
River otters are territorial animals: they mark their home range with feces and urine, and they will spray an odorous liquid from scent glands located under the tail. They also rub their musky scent on logs, stones, or mounds of grass throughout their home area. Otters become especially territorial during the breeding session. Males will sometimes fight, competing for females, if mutual avoidance does not work. A river otter's home range includes the area in which the animal lives, reproduces, and generally satisfies its life requirements. The home range is usually 5 to 48 miles. Prey availability, habitat, weather conditions, the reproductive cycle, and human encroachment can influence the home range.
River otters are active predators whose diet consists mainly of fish. In the water, they will also prey on snakes, frogs, lizards, turtles, crabs, crayfish, salamanders, water beetles, mussels, snails, worms and small birds such as ducks. On land, river otters prey on mice, small rabbits, and ground-nesting birds and their eggs. It is also common for otters to eat grasses, pond weeds, algae, and blueberries. A river otter can eat 15% to 20% of their body weight daily, which is around three pounds of food. Otters do not store food for future consumption, and they will not kill more than they can eat.
COWNOSE RAY (Rhinoptera bonasus) – has a very broad disk and pointed wings. Its snout is indented in the middle to form two lobes, hence the name ‘cownose'. Superficially, it resembles the eagle ray. The eyes are located in front, or anterior to, the beginning of the pectoral fins. It can grow to be seven feet wide and about 100 pounds. It may be seen in large schools in sand flats and mudflats stirring up food on the bottom with its wings, or pectoral fins.
SOUTHERN STINGRAY (Dasyatis americana) – an inshore species which spends much of its time in shallow areas of sand or mud bottom in search of its food. Its diet consists of clams, crabs, shrimps, worms, and small fish. Disk is rhomboid in shape like the Atlantic's disk, but is distinguishable by its blunt or rounded snout. The tail is rather long and whip-like with a barbed spine near the base.
ATLANTIC STINGRAY (Dasyatis sabina) – a prominently pointed snout distinguishes this ray from many of its relatives. Its dorsal surface is brown to yellowish-brown and its ventral side is whitish. It is a small species, growing to approximately 2 feet or 15 pounds.
SMOOTH BUTTERFLY RAY (Gymnura micrura) – has a very broad disk, much wider than it is long. Its tail is very short, with a keel on top and no tail spine. It is unique among stingrays in that it can vary its color to better blend in with the sandy bottom. The butterfly ray can grow to be about four feet in width. It can be found in waters that are a few feet deep to about 150 feet deep. It is most often seen in late spring and summer in shallow, warm waters.
LESSER ELECTRIC RAY (Narcine brasiliensis) – much smaller than the Atlantic torpedo, it can grow to about 15 inches. It lacks a stinging barb, but possesses two electric organs between its head and pectoral fins for self-defense and to stun its prey. Its larger cousin, the ATLANTIC TORPEDO (Torpedo nobiliana), can achieve a weight of more than 100 pounds. To stun its prey, the torpedo can administer a considerable electric shock. Voltages of 170 to 220 have been recorded. The electric ray and the electric eel are the only two species that can create enough charge to injure a human.
SPOTTED EAGLE RAY (Aetobatus narinara) – has a wide, diamond shaped disk with whitish, yellow, or green spots on dorsal side. The ventral side is relatively light in color. One or more sharp barbs are present at the base of a very long, black, whip-like tail. It has been known to grow to a width of 7.5 feet and a weight of 500 pounds. Eagle rays, as well as many other large rays may be seen swimming alone, in pairs, or in schools. They have shovel-shaped mouths with a wide, single row of teeth that allow them to dig up clams, oysters, and other organisms. Like some other large rays, they have been seen leaping clear out of the water and making loud, croaking sounds.
ATLANTIC MANTA (Manta birostris) – the largest ray. It can reach a width of 22 feet, a length of 17 feet, and a weight, which approximates 2 tons. It has two hornlike projections at the front of the head, which can help push food towards the mouth. These large creatures can oftentimes be seen basking near the surface of the water. Mantas are known to eat shrimp, mullet, and plankton. Juveniles eat anchovies, shrimp, and copepods.
DEVIL RAY (Mobula hypostoma) – resembles the manta ray, but it is considerably smaller, reaching about 4 feet in width.