Fraser’s dolphin is a mid-sized dolphin that can be found most commonly traveling in the Eastern Pacific Ocean.
These dolphins are known for their large pod sizes and tightly pack traveling behavior.
They are also known for their ability to dive to depths of more than 1,500 ft. where light does not inhibit the ocean.
At these levels it is likely that Fraser’s dolphin uses its echolocation abilities to navigate the pitch black waters and hunt for food.
Physical Characteristics and Appearance
At full maturity these dolphins are known to reach lengths of around 6 to 9 ft. and weigh between 350 – 450 lbs.
They have stocky bodies with a small triangular-shaped dorsal fin that tapers back and small flippers when compared to other dolphin species.
In terms of color Fraser’s dolphin has a grayish brown to grayish blue colored upper body with a cream-colored and dark blue line that runs from its beak to its anus.
The under body is typically a creamy white color, however some dolphins may have a pinkish tone.
As with other marine mammals/cetaceans these dolphins are warm-blooded, breathe air, give birth to their young and produce milk.
Diet and Hunting Methods
During deep dives Fraser’s dolphin can reach depths of over 1,500 ft.
The length of time these dolphins can hold their breath for when diving for food is unknown.
When searching for food in dark areas these marine mammals can use echolocation to navigate the ocean and find prey.
Given the fact that these dolphins are fairly social it is quite possible that echolocation may be used to help them orchestrate attacks and keep track of other pod members while hunting.
Habitat and Migration
Fraser’s dolphin is known to inhibit the tropical regions of the world and can be found traveling in the Eastern, Pacific and Indian oceans.
The most frequent spottings have occurred in the Eastern Pacific in the Gulf of Mexico, South Africa and South Australia as well as additional observations in places such as France and Uruguay.
Social Structure and Communication
These dolphins are known to be a very social species and have been spotted traveling in groups of anywhere from 100 to 1000 dolphins, although most groups contain 100 or less dolphins and some pods may contain as little as 10 dolphins.
When in a pod these dolphins are known to maintain a close tight proximity to one another keeping separated distances between dolphins limited.
During active times these dolphins can be seen swimming quickly and leaping out of the water as they swim.
In addition to traveling together Fraser’s dolphin may also be found grouped together with other dolphin species such as the false killer whale, melon-headed whale, Risso’s dolphin and the short-finned pilot whale.
Depending on the dolphins geographic habitat and pod’s social structure their behavior towards humans can vary.
In some pods/locations these marine mammals have been observed as being approachable and social towards humans while in other areas they tend to be shy and distant when among people.
Breeding and Reproduction
The exact gestation period for these dolphins is unknown however it is believed that the gestation period is 10 – 12 months long.
Once born the mother will nurse and care for her young until it is able to hunt and survive on its own.
Female dolphins give birth to a single offspring every 2 – 3 years.
The average lifespan for Fraser’s dolphins is estimated to be at least 18 years.
These dolphins are known to face threats from accidental catches in fishing nets and other fishing equipment as these dolphins often swim into the nets thinking that they’ve captured an easy group of prey.
In some locations these dolphins may also face threats from poachers looking to sell their meat to meat markets, supermarkets and restaurants or use their meat as a source of bait for other aquatic prey.
Below are the most common known threats for these marine mammals:
Bycatch– Bycatch is the accidental capture of marine mammals such as dolphins in fishing nets from fisheries in the area.
Trapped dolphins often drown as the nets they are captured in prevent them from surfacing for fresh air.
Hunting – In some instances these dolphins are hunted for commercial purposes such as having their meat sold or used for bait.
Pollution – A common threat among marine animals, especially in commercial zones is the threat of chemical pollution and waste.
These forms of pollution can lead to reproductive issues as well as numerous other health concerns among marine mammals as it can poison their food supply or harm them directly.