Fróðskaparrit - 01.01.1991, Page 40

44
STUDIES ON THE LONG-FINNED PILOT WHALE
the reservations concerning ages older than
13-15 years, a good agreement is visible. The
growth formulas for both sexes are:
0.120«)
L = 232.04 e0 ll20/0120<1'e'
L = 590cm
oo
-0.1681)
L = 223.69 e0 1172/0168<le
L = 440cm
OO
where L is length in cm and t is the age in
years.
The age frequency distribution showed
two concentrations of animals, one consist-
ing of immature whales up to 8 years for fe-
males and 15 years for males, and the other
consisting of the mature group, with a peak
at about 17 years of age for both sexes (Fig
3).
Length. 554 whales from 8 entire schools
were sexed and measured for length and
divided according to maturity (Fig. 6, a and
b). An average Faroese long-finned pilot
whale measures 405.1 i 4.1 cm, the males
423.8 í 7.7 cm on average (range: 186-625
cm, N = 229) and the females 391.8 í 4.2 cm
on average (range: 180-490 cm, N = 325). The
pattern did not differ from that previously
found by Joensen (1962) and Moore et al
(1978; 1979).
Lengths recorded in the Faroes agree with
previous observations that the Faroese long-
finned pilot whales grow longer than those
caught off New Foundland (Sergeant, 1977;
Moore et al 1978; 1979). The Faroese sam-
ples were more similar to the findings from
the British strandings, with males up to 630
cm and females up to 546 cm (Kock, 1956;
Martin, Reynolds and Richardson, 1987).
Body length, cm
Fig. 6. Length frequency distribution histogram for
males (a), and females (b) of long-finned pilot whales
in the Faroe Islands in the period 1978 to 1985. Empty
stacks = immature whales, filled = mature whales.
N=554.
This could be an indication of three things:
1) that Faroese and British pilot whales are
more closely related genetically, or 2) that
they may have better feeding conditions than
the pilot whales around New Foundland, or
3) that there could be more than one stock of
pilot whales.
The short-finned pilot whale, G. macro-
rhynchus, off Japan is shown to be divided
cr cr:
9 9: