Embedded Files
Taxonomy
Kingdom animalia
Phylum
chordata
Class mammalia
Family delphinidae
Order cetacea
Genus stenella
Species coeruleoalba
Description
The striped dolphin (stenella coeruleoalba) is a dolphin found in temperate and tropical waters all over the world. It is a member of the oceanic dolphin family, Delphienidea. What they are most known for and what sets them apart from other species of dolphins is their stripe that runs down their bodies.
Physical Description
Built like most oceanic dolphin species, striped dolphins are known for their distinct and striking side colouration pattern, which includes a bold, thin stripe that originates at the beak, encircles the eyes and extends one branch down to the flipper and the other down the side of the body. Above this black line, a wider brushstroke of blue/grey runs from head to tail, with a blaze running to the rear of the dorsal fin dividing the dark coloration of the back.
Closest living relative to this species
According to a study, the closest relatives of the striped dolphin are the Clymene dolphin, the common dolphins, the Atlantic spotted dolphin, and "Tursiops" aduncus, which was formerly considered a subspecies of the common bottlenose dolphin. The striped dolphin was described by Franz Meyen in 1833.
How long have they been in existence?
The family Delphinidae made its appearance around 11 million years ago,
Point Key Characteristics The Striped Dolphin is known for its striped physical feature going down its body, as that's they main giveaway. But also their behavior of being sociable and athletic, having a lot of energy and being active .
Differences between Males and Females
Females tend to be a little bit smaller than male striped dolphins.
Females also become sexually mature around ages 5-13 while males at 7-15.
Size 8 feet (females) 9 feet (males)
Weight 330 pounds (females) 350 pounds (males)
Life Span up to 58 years
Subspecies the striped dolphin does not have any
Diet
The diet of the striped dolphin is varied and may include fish, squid, octopus, krill and crustaceans. They feed anywhere within the water column where prey is concentrated and they can dive to depths of 700 meters to hunt deeper-dwelling species. They eat just about everyday and can eat up to 39 lbs worth. Striped dolphins are also usually found in tight, cohesive groups averaging between 25 and 100 individuals, meaning they’ll work together and hunt together.
Distribution & where they're found
Found worldwide in the ocean. Their ranges include waters off of Greenland, Northern Europe, the Mediterranean Sea, Japan, Argentina, South Africa. Western Australia, and New Zealand. They can also be found off the west coast in the northwestern Atlantic, and the Gulf of Mexico. Off the waters of Hawaii. Striped dolphins are highly social animals and are known to gather in large schools, consisting of more than 1000 individuals.
Temperature & Habitat
Striped dolphins prefer tropical to warm temperate waters (52 to 84° F) that are oceanic and deep. They tend to perfer deeper more offshore waters and can be found in the oceanic waters of the continetal shelves.
Ancestors and Evolution The evolution of dolphins, or Delphinus, is believed to have started with the Pakiectus, a four legged, land walking mammal. The dolphin is thought to have evolved alongside or from the Ambulocetus, Remingtonocetidae, Protocetid, Basilosaurudae, and Dorudontid to eventually become the Delphinus which is found in the Cetacea infraorder.
Invasive at all? they are not an invasive species
Rainfall does not matter
Animals
fish, squid, octopus, krill, and other crustaceans are all animals the striped dolphins eat.
while killer whales and sharks are the main predators of the striped dolphin.
But as they are found in schools, they'll also be found surrounded by a ton of other sea creatures and fish that they share their habitat with.
IUCN Rating
IUCN lists the striped dolphin as “lower risk/conservation dependent”. In the United States, striped dolphins are not listed as threatened or endangered. There is an estimate of 2 Million striped dolphins worldwide. Estimates of some regional populations include approximately 2,000,000 in the eastern tropical Pacific, 500,000 off Japan, 62,000 in the western Atlantic and 100,000 in the Mediterranean Sea.
Reproduction
Their mating system is generally unknown, but is thought to be polygynous, meaning one male mates with several females, but females only mating with one male. After. one year (12-14 months), females give birth to a single calf in the summer or autumn, with a three- or four-year gap between, to be able to raise their young.
Dolphins form decade-long social bonds, and cooperate among and between cliques, to help one another find mates and fight off competitors, new research has found.
Development
The estimated lifespan of striped dolphins is up to 58 years. They become sexually mature when they reach about 7 feet in length—between the ages of 5 and 13 years for females and 7 and 15 years for males. Baby dolphins suckle milk from their mother in order to feed and grow. Later on, their mother will introduce them to solid food. Young dolphins may stay with their mothers and the mother's group until they are some six or seven years old. Then the young dolphins will be old enough to become independent
Causes of Death
Disease
In the early 1990s, more than 1,000 striped dolphins died in the Mediterranean Sea from a morbillivirus epizootic—a temporary, highly contagious, widespread, and lethal disease outbreak—that may have been triggered by pollution (e.g., organochlorines) and fewer available prey. Environmental toxins and contaminants lower their disease immunity.
Hunting
Striped dolphins have been subjected to drive hunts in Japan and taken in Sri Lanka and the Caribbean. During the mid-20th century, as many as 21,000 animals were caught and killed each year.
Entanglement in Fishing Gear
One of the main threats to striped dolphins is becoming entangled or captured in commercial fishing gear such as trawls, gillnets, purse-seine nets, and hand-harpoons.
How long have humans been interacting with species isn’t specifically known but humans have been interacting with dolphins for as long as we have known of their existence.
Efforts being made to minimize impacts
All striped dolphins are protected under the MMPA. Our work protects striped dolphins by: Reducing entanglement in commercial fishing gear. Responding to dead, injured, or entangled dolphins.
Impact of Humans
-Hunting
-Catching
-Noise disturbance
-Contaminants
-Climate change
all cause a disturbance in the striped dolphins enviroment and life. Most leading to complications in health and can lead to death.
Potential Future impacts is global warming and making their environment harmful in anyway.
Social Structure
Live in packs or solo
Striped dolphins are a very social species. Groups/schools commonly consist of 10-30 individuals but can be up to several hundred and sometimes a thousand individuals of similar breeding status and age. Three different kinds of schools are generally observed across their distribution: juveniles, non-breeding adults, and breeding adults. When juveniles become mature, they either join a non-breeding or a breeding group depending on factors still to be understood.
Communication
Striped dolphins are believed to communicate within their social groups using elaborate whistle and click sequence. Like other cetaceans, they also use echolocation – a series of high frequency sounds to locate prey and orientate themselves underwater. As striped dolphins feed down to depths of 700m, the ability to use echolocation is essential since lighting underwater below a few meters is minimal.
Roles within community females will raise their youngs for the first few years of life, while the males will head off and join a different school. This beacuse males dont play apart in raising their offsprings.
Individuals that make up the group
How do they interact with each other
depends on what school or group the dolphin is in. Males will most likely be with other adult striped dolphins, in either a nonbreeding or breeding school. Males job is to fertilize the females.
while females groups will more likely have younger dolpins and or being with males ready to mate.
Competition Striped dolphins are in constant competition with humans over prey. The dolphins and fisheries compete over anchovies, tuna, and cod. Fisherman often kill striped dolphins that are caught in their fishing
the males will also often compete with other males for females
there is also terriotry competition.
Page updated
Report abuse