onfused With

At sea, blue whales may be confused with fin whales (p. 26) and though
the two are sometimes difficult to distinguish from a distance, the
following key differences permit identification at close range:

BLUE WHALE FIN WHALE

COLORATION

Mottled bluish gray above Gray above, white below; frequently
and below. grayish-white chevron
behind head, right lower
lip white.

BALEEN

All black. Bluish gray with yellowish-white
strips; front fifth to
third of baleen on right side
all white.

HEAD

Broad and nearly U-shaped; Narrower, more V-shaped;
all dark. right lower lip white.

DORSAL FIN

To 13 inches (33 cm); triangular To 24 inches (61 cm); falcate;
to moderately falcate; in located slightly more than a
last third of back; visible well third forward from tail
after blow. flukes; usually visible shortly
after blow.

SURFACING AND PREPARING TO DIVE

Often shows head and blowholes; Usually rolls higher out of
broad expanse of back water, particularly on long
and much later, dorsal fin. dive; dorsal fin visible shortly
after blow.

DIVING

Dives for 10-20 min; surfaces Dives 5-15 min (most often
and blows 8-15 times, making 6-7); surfaces steeply for 3-7
a series of 12- to 15-s dives blows then dives rather
between blows, then disappears steeply again; does not show
again; sometimes raises flukes on dive: on sounding,
flukes slightly on last dive; the maximum height of back
on sounding, the maximum in the area of dorsal fin which
height of back in the area of is exposed is approximately 2
dorsal fin which is exposed is times the height of the dorsal
approximately 4 times the fin.
height of the dorsal fin.