Pods are known to mass strand, possibly due to sheer accident, biosonars confused by geomagnetic anomalies, injury from loud military sonar, or disease.
[4] Worldwide, the diversity of mitochondrial DNA in short-finned pilot whales is considered to be low relative to other species with global distributions.
[7] Short-finned pilot whales are black to dark gray/brown, with a thick tail stock, fluke with sharply pointed tips, bulbous head, and a broad, sickle-shaped dorsal fin.
[4] Short-finned pilot whales also have fewer teeth – 7–9 in each row – and a shorter and broader rostrum with a premaxilla that covers more of the maxilla.
[14] Short-finned pilot whales are found in both coastal and pelagic waters in temperate and tropical regions of the Indian, Atlantic, and Pacific Oceans.
Beyond Japan, the Naisa-type occurs in southeast Asia, the Indian Ocean, and Hawaii, and the Shiho-type can be found in the California Current and off Peru.
The effects of tourism activities on pilot whales have not been well studied, but some evidence suggests that the impact of underwater noise from whale-watching boats can have the potential to significantly disrupt communication at close range.
[19] Many countries offer safe whale-watching guidelines designed to minimize the impact of their activities on the animals being watched (see supplementary materials).
[4] However, a study by Van Cise et al. (2017) showed that, in the Hawaii islands, the social organization of pods was indicative of familial behaviour rather than matrilineal, and was driven by genetic relatedness.
[23] In the closely related long-finned pilot whales, babysitting of calves by other group members is frequently documented, and can be performed by males as well as females.
[36] Three stocks of short-finned pilot whales are recognized in U.S. waters, which live along the east and west coasts, and around the Hawaiian Islands.
These estimates come from sightings reported from vessel and aerial surveys, and may be under-representing the true population abundance due to the wide range that the species covers, and the difficulty of distinguishing long-finned and short-finned pilot whales at sea.
[38] Records suggest they are also abundant in deep water off the west coast of Africa, around the Maldives, and in the northern Indian Ocean more generally.
Due to their tight social bonds, rescue attempts following strandings are not always successful, as whales will often re-strand themselves upon hearing the calls of their group members on shore.
[48] Other hunting methods include hand or crossbow-projected harpooning, and small-type whaling (defined as the use of a cannon mounted on a vessel below a certain size).
From 1993 to 2004, the annual quota for all short-finned pilot whale takes in Japan was 500, a large proportion of which was allocated to the drive hunt in Taiji.
[50] Certain Japanese restaurants serve pilot whale as sashimi, or as steaks that are marinated, cut into small chunks, and grilled.
Like many marine predators, pilot whales are susceptible to entanglement and bycatch in pelagic fishing gear, such as gill nets, long lines and some trawl fisheries.
[4] Once entangled or hooked, whales may drag the gear behind them for long distances, resulting in fatigue, compromised feeding ability, or injury, often leading to reduced reproductive success and death.
Short-finned pilot whales, have been kept in captivity in various marine parks off southern California, Hawaii and Japan, arguably starting the late 1940s.
For example, in the United States, NOAA Fisheries implemented the Pacific Offshore Cetacean Take Reduction Plan, which aims to reduce serious injuries and deaths of marine mammals incidental to the California/Oregon thresher shark/swordfish drift gillnet fishery through methods like gear modifications, limited fishing depth, and skipper education workshops.
[61] In areas where resident pilot whale populations are seen near the coast, such as those off the Canary Islands, Madeira, and Hawaii, they can be studied using photo-identification.
This technique helps researchers identify unique markings and scars on the whales' dorsal fins, which are used to recognize individuals from photographic surveys to monitor movements and life histories over time.
This makes assessing threats and population dynamics difficult, and more research is needed before any statements can be made on the global status of short-finned pilot whales.