LONGFIN PILOT WHALE Globicephala
Longfin Pilot Whales vary enormously with age and sex.
Description Medium; length averages 6 m (20 ft) for males, with a maximum of 8.5 m (28 ft), and 4.8 m (16 ft) for females, with a maximum of 6 m (20 ft); calves are about 1.8 m (6 ft) at birth. Weight of males can be up to 3,800 kg (4.25 tons) and of females up to 1,800 kg (2 tons); calves are about 100 kg (225 lb) at birth.
Calves of both sexes have a narrow head which tapers, much like that of the False
Killer Whale but as they mature the head fills out and becomes square and bulbous. In adult males the melon grows into a pronounced shiny black pot shape. There is no constriction between the head and the body and no beak at any stage, although the upper lip protrudes slightly.
Although the body is long, it is relatively slender and narrow along the tailstock where it is compressed to form substantial dorsal and ventral keels. The absence of a neck makes the flippers appear to be directly attached to the head. They are very long, about 20 per cent of total body length, bent sharply into an angular 'elbow' about halfway down their length, and sharply pointed. The fin is equally distinctive, relatively high, but so broad at the base that it seems low. It is placed forward of the midpoint of the body and sweeps strongly backwards from a leading edge that is thicker in males than in females. There is a report of at least one animal, seen in Newfoundland in 1964, in which the fin was triangular.
colour is mainly black or very deep grey, but on the throat, chest
and belly there is a white or pale grey anchor shaped marking. In most
individuals there is a medium grey saddle-shaped patch directly behind
the fin which is conspicuous at close quarters, but often difficult
to see in the field. There may also be small white blazes beneath the
chin and on the undersides of the flippers. Calves are more brownish
grey with a white mottling.
The most distinctive field characteristic is the strongly curved, long-based
fin, set well forward on the whale's back. This, coupled with the broad,
round foreheads of all adult animals, makes identification, at least
as far as the genus, relatively simple. Longfin
Pilot Whales can be distinguished
from Shortfin Pilot Whales (G. macrorhynchus 50) by their longer flippers
and the fact that the heads of adult male Shortfins are often set off
from the body by a dorsal notch in the neck at the position of the blowhole.
Both species normally travel in compact schools, slowly and steadily near the surface, rising to blow roughly once every 1 or 2 minutes. The dome of the head appears first, followed very quickly by a strong blast about 1.5 m (5 ft) high, which is clearly visible under most conditions. Then the head and the back and the entire fin remain in sight as the whale glides forward before submerging. Prior to a long dive, the body and fin are raised more deliberately and the flukes show clearly. The whales apparently have sufficient control over their buoyancy to sink straight down without arching or diving. Most dives are 30-60 m (lPO-200 ft) deep, but pilot Whales frequently go to very much greater depths, perhaps as much as 1,000 m (over 3,300 ft). This species is said to stay down for as long as 2 hours, but even if that were possible, it would be unusual. The duration of a normal feeding dive is 5-10 minutes.
Longfin Pilot Whales are largely indifferent to ships, seldom come close and never bowride, but schools can be approached to within 50 m (160 ft) by even a large vessel. In smaller boats we often manage to manoeuvre amongst a school and come within a boat length (6 m or 20 ft) of an individual before it sounds.
We once came across a group in mid-Atlantic resting motionless at the surface. When they became aware of us, several pitchpoled (sitting up vertically in the water with their heads exposed as far as the flippers) and held this position for up to 30 seconds. These same individuals then subsided and slapped their tails and flippers on the water several times before the whole school dived.
Breaching is rare, but we have seen juveniles leap clear of the water in a moving school, throwing themselves completely over in a backward somersault. The normal swimming speed is roughly 4-6 kph (2-3 knots), but in a panic Longfin
Pilot Whales are said to exceed 50 kph (25 knots).
We have seen them with Common Dolphins Ipe/phinus de/phis 75) and Bottlenose
Dolphins (Tursiops truncatus 76), with which there is no possibility of confusion, but they can be mistaken at sea for False
Killer Whales. Both species are dark, with prominent fins and 'elbowed' flippers. They can best be distinguished as follows:
Globicephala square head; robust body; broad-based, back curved fin;
grey saddle patch; seldom breaches; never bow¬rides.
Pseudorca tapered head; relatively slender body; narrow, pointed fin; back all black; often breaches and bowrides Social bonds amongst a group of Longfin Pilots are so cohesive that whatever happens to one seems to affect them all, and stranding is very common. One group of over 1,000 once hurled themselves ashore on Lofoten Island in Norway. A school is easily stampeded by the injury or stranding of any of its members, something which the whalers in the Faeroes have been quick to exploit; but large numbers of these whales frequently beach themselves without human assistance.
Each mature Longfin Pilot Whale consumes about 34 kg (75 lb) of mixed fish and squid daily. The most common food is squid, particularly ll/ex i/lecebroslIs, and the most favoured fish seem to be cod, horse mackerel and turbot.
Societies range from small groupS of half a dozen to large schools of
40-200. There is at least one report of a herd 3,000 strong. The structure
of the group depends on activity, and varies from travelling schools,
which move along on a broad front usually with large males in the lead,
through erratic feeding schools to 'loafing groups' in which the whales
lie about in disarray with fins and flippers showing, aparently sleeping
with their bodies in close contact. Herds are probably hierarchical and
polygamous, with young males (who are often more scarred than older ones)
bearing the brunt of aggression. Cohesion is so strong that fishermen
in Novia Scotia once hesitated to kill any group member for fear that
the leaders would sink their boats. Jaw-clapping, which produces
a sharp explosive sound, has been heard in threats.