Fróðskaparrit - 01.01.1991, Blaðsíða 31

Studies on the long-finned pilot whale
in the Faroes Islands, 1976-86
Dorete Bloch
Abstract
From 1978 to 1986, 10 schools of the long-
finned pilot whale, Globicephala melas,
were examined, as well as occasional sam-
pling of individual animals dating back to
1976.
Albino or discoloured pilot whales have
been observed occasionally over the years.
10 separate schools, containing a com-
bined total of 931 whales, were sexed. The
school size ranged from 24 to 316 animals.
The sex ratio was on average 58.2 t 1.8% fe-
males (range 45.2-64.4%). Looking at long
term patterns, it would appear that male fre-
quency increases with a greater abundance
of pilot whales around the Faroes. The aver-
age school contained 48.2% immatures,
38.9% mature females and only 12.9% ma-
ture males.
One school in particular, containing 73
animals, was examined for fighting marks.
About half of the immature whales, 57% of
mature females, and all mature males had
fighting marks. The hypothesis of the
present paper is that tooth scars derive from
intraspecific fighting.
The average length of 541 whales was
405.6 í 4.2 cm, with 391.7 t 4.3 cm as mean
length for females (range: 180-490 cm), and
425.4 í 7.9 cm as mean length for males
(range: 186-625 cm).
Age determination of 139 whales showed
that females live longer (max. 32 yrs) than
males (max. 27 yrs). The average age was
11.4 t 0.7 years, for females 12.5 t 0.9
years, and 10.0 t 0.9 for males.
The weight of 7 whole whales was meas-
ured before partition and calculated to be
about 100 kg at birth and 2.5 tonnes for big
males. The utilization of the whales for hu-
man consumption was as high as 54%,
higher than for fish (47%).
The skinn value was examined for 944
whales, and an average whale was found to
measure 6.1 t 0.1 skinn, while females on
average were 5.6 t 0.1 skinn and males 6.8 t
0.2 skinn.
The highest incidence of ovarian corpora
in a female was 15, not all of which resulted
in a calf. On average mature females ovulat-
ed 5.5 t 0.3 corpora.
The diet of the schools examined consisted
primarily of squid, with the favorite prey be-
ing Todarodes sagitatus, although some
other squid species and fish also occur.
In summary, then, the average long-finned
Fróðskaparrit 38.-39. bók (1989-90): 35-61