with Bryde's whales. But fin whales
seldom exhibit curiosity about boats. In addition, the dorsal fin of the
fin whale is larger, is located farther back on the back than that of
Bryde's whale, and does not become visible as soon after the blow. It is
also less likely to be worn on the rear margin than that of a Bryde's
whale.
The head of the fin whale is more acutely pointed. Furthermore, the
right lower lip and the right front baleen of the fin whale are white.
The baleen and the right lower lip of Bryde's whales are dark gray. If
the animals can be approached closely from the right side, positive
identification is possible using these differences in color.
Like Bryde's whales, minke whales often approach close to vessels. But
minke whales have an acutely pointed snout, a single head ridge, and a
white band on each flipper. Further, minke whales rarely reach 30 feet
(9.1 m) in maximum length.
Distribution
The distribution of Bryde's whales is rather poorly known, no doubt in
part, because the species is difficult to positively identify at sea,
and records of its occurrence may have often been confused with those of
sei whales, fin whales, or minke whales. From stranded animals and
confirmed sightings at sea, the species appears to be found primarily
near shore in areas of high productivity in tropical or subtropical
waters, though it ventures into warmer temperate waters as well. It has
been reported from Virginia south into the northeast Gulf of Mexico and
the southeast Caribbean, and southern West Indies (Curacao and Granada).
To date no migration has been described for the species.
Stranded Specimens
Stranded Bryde's whales can be positively identified by the three ridges
along the top of the head from the area of the blowhole to the tip of
the snout. All other species of balaenopterid whales, except humpback
whales have but a single ridge. If the head of a stranded specimen is
buried in sand, is decomposed beyond recognition, or is otherwise
inaccessible for identification, Bryde's whales can still be
distinguished from sei whales by differences in the relative lengths of
the ventral grooves (Table 2) and from both the fin whale and the sei
whale by differences in the characteristics of the baleen plates (Table
2).
[Illustration: Figure 30.--On the head of this Bryde's whale off La
Jolla, Calif. two of the three head ridges characteristic of the
species, the main ridge and the left auxiliary ri
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