Short-finned Pilot Whale (Globicephala macrorhynchus)
Short-finned Pilot Whale
Photo: © Alice MacKay, Courtesy Cascadia Research. MMPA Scientific Research Permit No. 731
Did You Know?
· The longest known dive of a short-finned pilot whale lasted 15 minutes.
The long-finned pilot whale (Globicephala melas) is another species of pilot whale.Species Description
Short-finned pilot whales are larger members of the dolphin group reaching average lengths of 12 feet (3.7 m) for females and 18 feet (5.5 m) for males with maximum male size of 24 feet (7.3 m). Adult weight is 2200 to 6600 pounds (1000 to 3000 kg).
They have a bulbous melon head with no discernable beak. Their dorsal fin is located far forward on the body and has a relatively long base. Body color is black or dark brown with a large gray saddle behind the dorsal fin.
They are polygynous (males have more than one mate) and are often found in groups with a ratio of one mature male to about every eight mature females. Males generally leave their birth school, while females may remain in theirs for their entire lifetime.
Gestation lasts approximately 15 months while lactatation lasts for at least two years. The last calf born to a mother may be nursed for as long as 15 years. The calving interval is five to eight years, but older females do not give birth as often as younger females. Maturity occurs around 10 years of age and maximum longevity is 45 years for males and 60 years for females.
Short-finned pilot whales often occur in groups of 25 to 50 animals.
They feed primarily on squid, but they may also feed on octopus and fish, all from moderately deep water of 1000 feet (305 m) or more. When they are swimming and probably looking for food, pilot whales form ranks that can be over a kilometer (more than 1/2 mile) long.
They prefer warmer tropical and temperate waters and can be found at varying distances from shore but typically in deeper waters. Areas with a high density of squid are their primary foraging habitats.
Short-finned Pilot Whale Range Map
(click for larger view PDF)
Short-finned pilot whales are found primarily in deep waters throughout tropical and subtropical areas of the world. There are four recognized stocks in the U.S.: West Coast, Hawaii, Northern Gulf of Mexico, and Western North Atlantic.
Current population sizes for the different U.S. stocks are as follows: California, Oregon, and Washington - 300; Hawaii - 8,850; Western North Atlantic - 31,100 (estimate includes long-finned pilot whales); and Northern Gulf of Mexico - 2,400. See below for links to the most recent stock assessments for the U.S. populations.
Short-finned pilot whales were once commonly seen off Southern California, with an apparently resident population around Santa Catalina Island. After a strong El Niño in 1982-83, short-finned pilot whales virtually disappeared from this area, and despite increased survey effort along the entire U.S. west coast, few sightings were observed from 1984-1992. A 1996 NMFS survey cruise documented a few animals; none were sighted during a 2001 cruise. As these animals may move outside the U.S. "Exclusive Economic Zone", it is hard to determine if these numbers represent a trend. There are not enough data to determine trends in the Hawaii, Western North Atlantic, or Northern Gulf of Mexico stocks.
Bycatch in fishing gear is the primary threat to pilot whales. Several types of commercial fishing gear, including gillnets, longlines, and trawls, incidentally take short-finned pilot whales. Short-finned pilot whales have been documented entangled, hooked, and captured in these various types of fishing gear.
Drive fisheries that specifically target pilot whales exist in Japan and the Lesser Antilles.
Ship strikes may also pose a threat in Hawaii as propeller scarred whales have been documented.
Short-finned pilot whales are classified as Lower Risk-Conservation Dependent on the IUCN Redlist .
In 1997, NMFS implemented the Pacific Offshore Cetacean Take Reduction Plan, which requires the use of pingers and 6-fathom net extenders in the CA/OR drift gillnet fishery to reduce bycatch of cetaceans, including short-finned pilot whales. The Pacific Offshore Cetacean Take Reduction Team continues to meet and recommend measures to further reduce bycatch and achieve MMPA goals.
In 2005, NMFS convened the Atlantic Pelagic Longline Take Reduction Team to address bycatch of both short-finned and long-finned pilot whales in the mid-Atlantic region of the Atlantic pelagic longline fishery. The team submitted their recommendations to NMFS in 2006. A proposed rule to implement the pelagic longline take reduction plan was published on June 24, 2008. NMFS published a final rule to implement the PLTRP [pdf] (74 FR 23349) on May 19, 2009.
|Pacific Offshore Cetacean Take Reduction Plan (POCTRP) Interim Final Rule to Amend Pinger Specifications||64 FR 3431||01/22/1999|
|POCTRP Final Rule to Require New Training, Equipment, and Gear Modifications for CA/OR Drift Gillnet Fishery||62 FR 51805||10/03/1997|
|Stock Assessment Reports||n/a||various|
- NMFS Southwest Fisheries Science Center Pilot and False Killer Whale Information
- Pelagic Longline Take Reduction Team (PLTRT)
- Pacific Offshore Cetacean Take Reduction Plan (POCTRP)
- Listen to Pilot Whale Sounds
- Mass Stranding in North Carolina, January 2005
- Ocean Biogeographic Information System (OBIS-SEAMAP) Short-finned Pilot Whale Species Profile
Updated: December 12, 2012