Fróðskaparrit - 01.01.1991, Page 35

STUDIES ON THE LONG-FINNED PILOT WHALE
39
Fig. 2. Pilot whales in Faroe Islands assessed in official
skinn value. The whale shown is 7 skinn in value.
sheriffs, exist as far back as 1584, and are
unbroken from 1709 (Bjørk 1963, III: 184).
A comparison of this traditional assessment
with biological parameters is discussed by
Bloch and Zachariassen (1989).
Sex, length, and official number. In con-
junction with the examination of the
schools, the official whale number was
recorded together with the skinn value, so it
was possible to combine traditional statistics
with biological parameters. The sex was not-
ed, and the body length was measured to the
nearest cm as a straight line parallel to the
backbone from the snout to the notch in the
tail, according to the standard (Norris,
1961). In all, the length of 545 whales was
measured, and the sex of 970 recorded. (For
details see Table 1).
External marks. Features such as wounds,
fighting marks, Jice, and cephalopod marks
were noted. Fighting marks were difficult to
see, unless the animal was recently killed and
still wet. External marks were noted in par-
ticular from a catch of 73 animals in Vest-
manna on July 17, 1984.
Teeth. The teeth were used for age determi-
nation by reading the dentine layers at least
twice, according to the theory that a growth
layer group (GLX3) is deposited in the dentine
as well as the cementum every year, accord-
ing to Sergeant (1959; 1962), Perrin and My-
rick (1980) and verified by Lockyer (in print,
a).
The easiest way to collect the teeth was to
cut off most of the mandible using a chain-
saw. In three schools - Tórshavn, November
2, 1978 and August 28, 1979, and Fugla-
fjørður, August 21, 1984 - teeth were taken
from all whales, while only some were taken
from other schools. In total, teeth from 269
whales were sampled (see Table 1). Later the
jaws were boiled in water for a few minutes
to loosen the teeth in their sockets, and 2
good teeth were imbedded in liquid plastic
and cut in 1 mm slices lengthwise using a di-
amond saw. The reading of the sections was
performed with 12 times power magnifica-
tion. The slices were placed in glycerine mak-
ing them easy to read at once, due to the
opalizing effect of the glycerine on the sur-
face of the slices.
From Fuglafjørður, August 21, 1984, some