The short-finned pilot whale is a dolphin that has earned its name due to its whale-like appearance and because it is smaller compared to its long-finned cousin. As with the long-finned pilot whale, they are a very social species that can be seen traveling in groups of 10 to several 100 dolphins and are rarely spotted traveling alone.
In terms of location, the short-finned pilot whale can be found traveling throughout the world’s major oceans in tropical/subtropical climates. As a whole, these marine mammals make up one of over 40 known dolphin species currently in existence.
Physical Characteristics and Appearance
When fully grown, the female short-finned pilot whale grows to an average length of 12 ft. long, with males growing closer to 18 ft. long. While they are shorter in size than the long-finned pilot whale, these marine mammals tend to be larger than the average dolphin Weight ranges for these dolphins can vary anywhere from 2,000 lbs. to over 6,500 lbs.
They have a rounded bulbous-shaped head, hooked dorsal fin, and sickle-shaped flippers. As an adult, the overall body appears thick and stocky in nature. As with their long-finned cousins, these dolphins are primarily a dark grey to black in color and have a light grey to white patch on their stomachs. They may also appear to be a dark brownish color in some cases.
Diet and Hunting Methods
The short-finned pilot whale is known to consume a diet consisting of fish, squid, and octopus, with their primary diet consisting of squid. At night or in dark areas, these dolphins use echolocation to navigate the ocean and search for food.
By bouncing high-pitched sounds off of nearby objects, the short-finned pilot whale can tell the size, distance, density, and speed of various objects to figure out exactly what type of prey they are hunting and get its precise location. During deep dives, the short-finned pilot whale is known to dive to depths of 1000 ft. or more to locate potential prey.
Habitat and Migration
These dolphins can be found traveling throughout the world’s tropical and subtropical oceans and generally prefer living in deep waters far from the coastline. They are known to inhabit various oceans such as the Atlantic, Pacific, and Indian oceans, as well as the Red Sea.
Social Structure and Communication
The short-finned pilot whale is considered a social marine mammal and can often be found traveling in pods of 10 or more. In numerous cases, these marine mammals have been spotted gathered in groups of 25 – 50; pods may aggregate into larger groups that can include several hundred dolphins.
As far as swimming behavior, these dolphins have been seen lob tailing, spy hopping, and logging around at or near the surface. Breathing behavior is much less common in these dolphins when compared to other species. The communication involved clicking and whistling sounds which can also help these dolphins echo-locate.
Breeding and Reproduction
The average gestation period for these dolphins is around 15 months. After birth, newborn dolphins are fed milk until they can hunt for themselves and digest normal foods. Even after consuming food, they may continue to drink milk from their mother’s nipple for up to 2 years while lactating.
The nursing period for young dolphins may last as long as 15 years, and unlike the males, female dolphins generally stick with their birth school throughout their entire life. Sexual maturity is believed to occur between the ages of 8 – 12, at which point young pilot whales may begin mating and reproducing. Male dolphins are believed to have a lifespan of at least 35 – 45 years, while female dolphins may live until their 60’s.
Threats
The short-finned pilot whale is known to face several threats. One of the largest threats to these marine mammals is hazards from fishing equipment such as gillnets, hooks, and longlines. Fishing nets may threaten pilot whales as they attempt to search for prey. They may either try to capture the prey in the gillnets or accidentally run into a gillnet they didn’t notice.
Once trapped by these nets, the short-finned pilot whale can easily drown as the net prevents them from resurfacing and obtaining oxygen. They may also face threats from collisions with large ships or passing vessels that can strike them and cause serious damage. In some cases, pilot whales have even been observed with scars caused by strikes made by the propeller of a passing boat.
In terms of pollution, these marine mammals may be susceptible to noise and water pollution. Noise pollution is caused by artificial human-made sounds that can interfere with the pilot whales’ hearing and echolocation. These sounds can cause disorientation, create confusion when combined with other natural noises, and even cause lesions when they are too loud.
Lastly, pilot whales have been known to be hunted in certain areas for their meat, and while they are a protected species, some countries may not ban hunting these marine mammals or may place certain restrictions that allow a certain amount of hunting.
Predators
Aside from humans, little information exists regarding these marine mammals being hunted by other animals.
Captivity
Pilot whales have been held in captivity in numerous cases since the 1970s; captive numbers appear fairly low. Those held in captivity have shown significantly reduced lifespans leading many to suggest that they need to live in their natural habitat to survive and thrive.
Over the decades, these marine mammals have been held in captivity for research purposes, displayed in aquariums, and possibly for rescue and recovery. The length of captivity may vary from a few weeks/months to the entire life of these marine mammals depending on the situation.