FALSE KILLER WHALE

Scientific name: Pseudorca crassidens

Adult: Weight 1 to 2 tons
Length 4.3 to 6 meters

Newborns: Weight 75 to 85 kg
Length 1.6 to 1.9 meters

Distribution: Occurring mainly offshore in deep, warm, temperate to tropical oceans of the world.

Physical Features: Dark gray to black color over their entire body except for a light grey “W-shaped” crest on chest. Their head shape is round, and different from dolphins in that they have no long, pointed rostrum. Their bodies are long and slender with “S-shaped” pectoral fins with pointed tips and a rounded dorsal fins. They have large conical shaped teeth just like those of a true killer, which is where they get the name “false” killer whale.

Group Size: They always travel in groups with a minimum of 5 animals, an average of 50, and as many as 300 members.

Behavior: Pseudorcas are highly active and playful for their large size, frequently leaping out of the water, displaying breaches, lob-tails, and bows. They are seen following boats or riding in the wake. In captivity, false killer whales seem to show less aggression than some of their other dolphin relatives. However, they can be fierce predators in the wild. They have been observed attacking large whales and it is believed they will also attack and eat small dolphins.

Reproduction: They become sexually mature at 8 to 14 years and can breed year round. Gestation is estimated at 11-12 months but there have been cases of nearly 15 ½ months. Infants nurse for up to 18 months.

Diet: They eat a variety of fish although there is not a lot of information on exact species. They have been observed eating squid, large fish and other cetaceans.

Longevity: Little is known about the longevity of these animals in the wild. In captivity individuals have been documented to live as long as 13 years.

Conservation Status: There is very little information about the status of false killer whale populations, primarily because of their wide distribution. These animals are affected by pollution, over- fishing, fishing nets left in the water, and hunting. We can help them by learning more about them and preserving their habitat.

BOTTLENOSE DOLPHIN

 

ROUGH-TOOTHED DOLPHIN

 

Scientific name: Steno bredanensis

Adult: Male: 2.2 and 2.6 m (7ft-8ft 6in) in length. Female: 2.3 and 2.4 m (7ft 6in and 8 ft).

Newborns: 1m (39 inches)

Distribution: Seen in deep, offshore, warm waters. Avoid places with cold currents.

Physical Description: Unlike other dolphins, rough-toothed dolphins do not have prominent beaks with a crease between their beak and forehead. Instead they have a long narrow beak that slopes smoothly into the forehead.

Group Size: Rough-toothed dolphins are commonly seen in groups of about 10-20, sometimes up to 50 individuals. They are occasionally seen in groups of several hundred and mixed with other groups of dolphins.

Behavior: Rough-toothed dolphins are fast swimmers and often swim just under the surface with the dorsal fin and part of the back showing above the water. Sometimes they swim with only their head showing above the water - this is called porpoising. They can stay under water for up to 15 minutes. They can be seen to bow ride, though not as often as other dolphins.

Diet: They eat a variety of fish, squid and octopus.

Conservation: Small numbers of individuals have been seen caught in seine nets by tuna fishers and harpooned by Japanese whalers. The population estimate is at 150,000. (http://en.wikipedia.org/wiki/Rough-toothed_Dolphin).

PANTROPICAL SPOTTED DOLPHIN

 

Scientific name: Stenella attenuata

Adult: Male: 6.5 to 8.5 feet (2 - 2.6 m)
Female: 6 to 8 feet (1.9 - 2.4 m)

Newborns: 2.5 feet (0.7 m)

Distribution: Coastal to offshore. Mainly tropical, some subtropical and warm temperate world waters

Physical Description: Spots are the defining characteristics of this species in adults. New borns and young individuals, however, are generally uniformly colored. This species has a long thin beak and the chin, throat and belly are white to pale grey with a limited amount of spots.

Group Size: They swim in schools ranging from a few to a few thousand individuals and are quite active.

Behavior: The Pantropical Spotted Dolphin is very active and commonly makes large leaps from the sea. They exhibit a wide variety of aerial behavior, but not spinning. They are very active at the surface, bowriding, leaping to great heights, porpoising, and lobtailling.

Reproduction: The breeding system is unknown but may be similar to the spinner dolphin. Breeding is seasonal. Females reach maturity at 9-11 years old, males at 12-15 years. Gestation is up to 11.5 months. The calf is around 80-85 cm long.

Diet: They eat a variety of fish and squid on the surface and mid-water regions.

Longevity: Estimated to live up to 45 years.

Conservation Status: The Pantropical Spotted Dolphin is in danger due to the yellow-fin tuna fishery. In the 1960s and 1970s fishermen would capture thousands of dolphin and tuna at once using purse seine nets. Over a period of about 25 years 75% of this region's population, and over half the world's total was wiped out. The estimated current population is unknown.
(http://en.wikipedia.org/wiki/Pantropical_Spotted_Dolphin).

SOUTH AMERICAN SEA LION

 

Common name: South American Sea Lion
Patagonia Sea Lion

Scientific name: Otaria byronia
Otaria flavescens

Males: Weight 300 to 340 kg
Length 2.3 to 2.8 meters

Females: Weight 140 to 150 kg
Length 0.73 to 0.85 meters

Newborns: Weight 10 to 15 kg
Length 0.73 to 0.85 meters

Distribution: West and East Coast of South America, from Northern Peru around the Southern tip of South America, up to Southern Brazil.

Physical Features: They are generally a shade of brown to golden with some variation in individuals. Adult bulls have a dark brown coat with a long mane of course fur surrounding their neck and chest. Females have a lighter brown to golden coat. Both males and females have lighter bellies.

Breeding Season: Mid December to mid January

Reproduction: Like other sea lions, these animas have what is called “delayed implantation”. That means that males and females come together in December and January. At that time the pregnant females give birth, and they also breed with a male. However, the egg is not implanted inside her body for another 3 months. That allows the female to begin nursing and caring for her newborn pup before she becomes pregnant again. Males and females become sexually mature between 5 to 9 years, although some animals have given birth at younger ages. Once the egg is implanted, gestation is around 9 months. Mothers nurse their young for up to 9 - 12 months.

Longevity: Animals in the wild have been documented to live 12 to 18 years on average. Animals in captivity often live longer, with some living up to 25 years.

Conservation Status: The populations of these sea lions are widely distributed through out South America. The population is considered stable at around 300,000 individuals. These animals are still-hunted in some countries, oftentimes to eliminate them as competition for fishermen. They are also effected by pollution, over fishing, nets and other human activities.