What is your animal? The Bottlenose Dolphin
What is the scientific name and classifications of your animal?
Dolphins and their immediate kin are included in the scientific family Delphinidae. This family is represented by about 30 species, including common dolphins, pilot whales, killer whales, and false killer whales.
Describe the physical features of your animal?
. Bottlenose dolphins measured off Sarasota, Florida averaged 2.5 to 2.7 m (8.2-8.9 ft.) and weighed between 190 and 260 kg (419-573 lb.) (Read, et al., 1993).
2. Differences in body size and skull dimensions may be related to habitat differences. The two northwestern Atlantic ecotypes exhibit a pronounced size variance (Herse and Duffield, 1990).
. Large bottlenose dolphins in the Pacific may be 3.7 m (12 ft.) and weigh 454 kg (1,000 lb.). In the Mediterranean, bottlenose grow to 3.7 m (12 ft.) or more.
Each lobe of the tail is called a fluke.
2. Flukes are flattened pads of tough, dense, fibrous connective tissue, completely without bone or muscle.
3. Longitudinal muscles of the back and caudal peduncle (tail stalk) move flukesup and
down to propel a dolphin through water.
In which oceans does your animal live in ?
.
Bottlenose dolphins inhabit temperate and tropical waters throughout the world.2. In the Pacific Ocean, bottlenose dolphins are found from northern Japan and California to Australia and Chile. They are also found offshore in the eastern tropical Pacific as far west as the Hawaiian islands. Off the California coast bottlenose dolphins have been observed as far north as Monterey, particularly during years of unusual warmth (Wells, et al., 1990).
3. In the Atlantic Ocean, bottlenose dolphins are found from Nova Scotia and Norway to Patagonia and the tip of South Africa. They are the most abundant dolphin species along the United States from Cape Cod through the Gulf of Mexico.
4. Bottlenose dolphins are also found in the Mediterranean Sea, and in the Indian Ocean from Australia to South Africa.
What is the diet of your animal?
Dolphins are active predators and eat a wide variety of fishes, squids, and crustaceans such as shrimps. The foods available to a dolphin vary with its geographic location (Barros and Odell, 1990). . Adult bottlenose dolphins eat approximately 4% to 5% of their body weight in food per day. A nursing mother's daily intake is considerably higher: about 8% (Cockcroft and Ross, 1990). Feeding behavior is flexible and adapted to a dolphin's particular habitat and available food resources.2. Dolphins do not chew their food. Usually they swallow fish whole, head first, so the spines of the fish won't catch in their throats. They break larger fish by shaking them or rubbing them on the ocean floor.
What special behavior does your animal show?
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Bottlenose dolphins live in groups called pods In general, size of pods tend to increase with water depth and openness of habitat. This may be correlated with foraging strategies and protection Several pods may join temporarily (for several minutes or hours) to form larger groups called herds or aggregations. Up to several hundred animals have been observed traveling in one herdHow dose your animal reproduce and care
for its young? Age when attaining sexual maturity is variable among bottlenose dolphins. On average, females become sexually mature when they reach about 2.3 m (7.5 ft.), at about 5 to 12 years. Males become sexually mature when they reach about 2.4 to 2.6 m (8-8.5 ft.), at about 1 0 to 12 yearsMost dolphin births along coastal Texas waters occur in March Sometimes an assisting dolphin may stay close to the new mother and calf. Although this assisting dolphin often is referred to as an "auntie" dolphin, it may be male or female. This "auntie" dolphin is often the only other dolphin a mother allows near her calf A mother dolphin stays close to her calf and attentively directs its movements. The baby swims close to its mother and is carried in the mother's "slip stream," the hydrodynamic wake that develops as the mother swims. This helps the baby to swim and enables the mother and calf to stay up with the group.
What special senses does your animal have?
. Most sound reception, or hearing, probably takes place through the lower jaw. Studies show that the lower jaw most effectively receives sounds with frequencies above 20 kHz (Brill, et al., 1988). A dolphin may also receive sound through soft tissue and bone surrounding the ear.b. Unlike humans, a dolphin's inner ear is encased in a separate bone, called the auditory bulla, which is connected to the skull with fibrous tissue. Thus, the bulla is essentially isolated from the skull, and sound enters the ear most efficiently through the jaw and middle ear.c. A fat-filled cavity in the lower jawbone appears to conduct sound waves through the jaw to bones in the middle ears. The lower jawbone of toothed whales broadens and is hollow at the base, where it hinges with the skull. Within this very thin, hollow bone is a fat deposit that extends back toward the auditory bulla (earbone complex). Sounds are received and conducted through the lower jaw to the middle ear, inner ear, and then to hearing centers in the brain via the auditory nerve. (Brill, et al., 1988).
Include general information?
Swimming speed and duration are closely tied: high-speed swimming probably lasts only seconds while low-speed swimming may last for longDraw a detailed picture of your animal
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