Long-finned pilot whale - Globicephala melas
Taxonomy & Nomenclature
Physical Description / Field Identification
Pilot whales are large, with bulbous heads, dramatically upsloping mouthlines, and extremely short or non-existent beaks. The head is globose, with an upsloping mouthline. The flippers are extremely long (up to 1/4 of the body length) and slender, with pointed tips and an angled leading edge that forms an "elbow." The dorsal fin is about 1/3 of the way back from the snout tip, and is low, wide-based, and falcate. The tail stock is deepened (remaining more-or-less uniform in height from the saddle patch to just ahead of the flukes). Males have larger, more bulbous heads, thicker dorsal fins, and deeper tail stocks.
Predominantly dark gray to black, pilot whales have a white to light gray anchor-shaped patch on the chest, a light gray post-dorsal fin saddle, and light gray "eyebrow" streaks. Inside the mouth are 8-13 pairs of sharp, pointed teeth in each jaw. Newborns are 1.7-1.8 m long. Adults reach 6.7 m (males) and 5.7 m (females) in length. Bulls reach weights of 2000 kg.
Can be Confused With
In some temperate waters (for example, the waters around Cape Hatteras, NC), long-finned and short-finned pilot whales overlap in distribution. In these areas, the two species are extremely difficult to distinguish at sea. Tooth counts and relative flipper lengths (both of which are generally not useful in at sea sightings) are the only reliable means of separating the two. In the lower latitude areas of its range, the long-finned pilot whale can be confused with false killer whales or, less likely, pygmy killer and melon-headed whales; however, the differences in head shape and dorsal fin shape and position should permit correct identification.
Distribution
The long-finned pilot whale is widely distributed in the temperate, sub-polar waters of the world (with the exception of the North Pacific) and two subspecies are separated from each other by tropical waters: G. m. edwardii in the south and G. m. melas in the north. Long-finned pilot whales prefer areas of high relief, submerged banks, and the edge of the continental shelf.
In the eastern North Atlantic, long-finned pilot whales inhabit the Barents Sea and the coast of Norway, the waters surrounding the Faeroe Islands and British Isles, the west coasts of France and Spain and the waters of the Azores Islands, Madeira Island, and Mauritania. In the western North Atlantic, pilot whales occupy the coasts of Iceland and Greenland, along the continental shelf and coast of North America including the coast of Newfoundland, Georges Bank, the Gulf of Maine, and south to Cape Hatteras, with rare sightings further south. From Cape Hatteras north to Georges Bank, long-finned pilot whale sightings are concentrated between the 100- and 2000-m contours, although sightings have occurred in shallow and deep ocean waters as well.
In the Mediterranean Sea, long-finned pilot whales appear in the coastal waters of Spain, France, and the west coast of Italy, with local concentrations in the Alboran and Ligurian Seas.
The long-finned pilot whale is circumglobal in the southern hemisphere, from the east coast of South America, the coast of South Africa, the southern coast of Australia, Great Barrier Island in New Zealand, and the Chilean coast. The long-finned pilot whale’s range extends as far south as the Antarctic Convergence.
Ecology and Behavior
Pilot whales are highly social; they are generally found in pods of about 20-100, but some groups contain over 1,000. Based on photo-identification and genetic work, researchers believe pilot whales live in relatively stable pods like those of killer whales, and not in the fluid groups characteristic of many smaller dolphins. The mating system is hypothesized to be polygynous; this is consistent with the observed sexual dimorphism and adult sex ratio. Breeding can apparently occur at any time of the year, but peaks occur in summer in both hemispheres.
Pilot whales are apparently deep divers and inhabit shelf/slope waters. Groups often forage in broad ranks, sometimes with other species. Although they sometimes are aerially active, pilot whales are often seen rafting in groups at the surface, apparently resting. This is one of the species involved in mass strandings. Strandings are fairly frequent, for instance, on Cape Cod, Massachusetts, United States beaches from October to January. Their tight social structure also makes pilot whales vulnerable to herding, and whalers take advantage of this trait in drive fisheries off Newfoundland, the Faeroe Islands, and elsewhere.
Feeding and Prey
Long-finned pilot whales have a broad diet and are primarily squid eaters, but will eat small fish as well.
They utilize sucking as their feeding mode; the large tongue of the long-finned pilot whale is depressed and retracted during feeding, causing negative intraoral pressure during capture.
Prey species include:
Cephalopods:Gonatus fabricii, Illex illecebrosus, Loligo pealei, Todarodes sagittatus, Gonatus sp., Brachioteuthis sp., Sepiola sp., Teuthowenia megalops, Histioteuthis sp., Eledone cirrhosa, Histioteuthis reversa, Chiroteuthis imperator, Chiroteuthis veranyi, Selenoteuthis scintillans, Megalocranchia sp., Rossia macrosoma, Mastigoteuthis sp., Ommastrephes sp., Ommastrephes bartramii, Onychoteuthidae
Other invertebrates: Aphrodite aculeata, Nereis sp., Yoldiellasp., Tyblomangelia nivalis, Pandulus montagui, Munida tenuimana
Fish: Gadus morhua, Merlicciussp., Reinhardtius hippoglossoides, Scomber scombrus, Argentina silus, Micromesistius poutassou, Gadiculus argenteus, Trisopterus sp., Coryphaenoides sp., Lycodes sp., Brosme brosme, Ammodytes sp., Merlangius merlangius, Glyptocephalus cynoglossus, Melanogrammus aeglefinus, Trichiuridae, Caranx trachurus, Clupea harengus, Merluccius bilinearis, Urophysis sp., Squalus acanthias.
Threats and Status
Main threats for long-finned pilot whales include harvest, fisheries bycatch, entanglement in debris/fishing gear, noise pollution, and heavy metal and organochlorine pollution.
The pilot whale is not listed as endangered or threatened by either the IUCN or the United States government. Long-finned pilot whales have been taken directly in several large scale drive fisheries in the North Atlantic Ocean. The most famous of these occurred historically in Newfoundland, and another one still occurs in the Faeroe Islands. Other such drive fisheries used to occur in the United States (Cape Cod), Norway, Iceland, Greenland, and Scotland (Orkney and Hebrides Islands).
In addition, there are incidental catches in several fisheries, especially trawls, driftnets, and longlines. Accumulation of heavy metals, PCB, and DDT in the tissue of long-finned pilot whale is also a concern. In the United States, the National Marine Fisheries Service assesses the long-finned pilot whale in conjunction with the short-finned pilot whale (G. macrorhynchus) due to difficulties discerning between the two at sea. The 2002 assessment of Globicephala spp. in the western North Atlantic placed the population of United States stocks at 14,524 (CV=0.30). The International Whaling Commission placed population in the central and eastern North Atlantic at between 440,000 and 1,370,000.
Links
References
Abend, A.G. and T.D. Smith. 1999. Review of distribution of the long-finned pilot whale (Globicephala melas) in the North Atlantic and Mediterranean. U.S. Department of Commerce, NOAA Technical Memorandum NMFS-NE-117.
Bernard, H.J. and S.B. Reilly. 1999. Pilot whales Globicephala Lesson, 1828. pp. 245-280 in S.H. Ridgway and R. Harrison, eds. Handbook of marine mammals, Vol. 6 The second book of dolphins and the porpoises. Academic Press.
Boyd, I.L., C. Lockyer and H.D. Marsh. 1999. Reproduction in Marine Mammals. pp. 218-286 in J.E. Reynolds and S.A. Rommel, eds. Biology of Marine Mammals. Smithsonian Institution Press, Washington, DC.
Donovan, G.P., C.H. Lockyer and A.R. Martin (eds.). 1993. Biology of Northern Hemisphere pilot whales. Reports of the International Whaling Commission, Special Issue 14, 479 pp.
Gannon, D.P., A.J. Read, J.E. Craddock, K.M. Fristrup and J.R. Nicolas. 1997. Feeding ecology of long-finned pilot whales Globicephala melas in the western North Atlantic. Marine Ecology Progress Series 148:1-10.
Olson, P.A. and S.B. Reilly. 2002. Pilot whales Globicephala melas and G. macrorhynchus. pp. 898-903 in W.F. Perrin, B. Würsig and J.G.M. Thewissen, eds. Encyclopedia of marine mammals. Academic Press.
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ITIS TSN | 552461 |
Status - ESA, U.S. FWS
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Status - Red List, IUCN
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DD (Mediterranean) DD (Europe) LC (Global) |
#records (spatial) | 10,103 |
#records (non-spatial) | 0 |
#datasets | 76 |
Year | 1893 - 2024 |
Latitude | -69.79 - 79.92 |
Longitude | -166.60 - 178.80 |
See metadata in static HTML |
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