Marine Mammals

Unlike seabirds, marine mammals spend most of their time underwater, coming to the surface to breathe, and rarely do you see the whole animal. Views can be brief, and we provide the clues needed to identify species based on what you are likely to see — a fin, a blow, a tail going down.

As with 'seabirds,' some 'marine mammals' live along the coast, such as Harbor Seals and Gray Seals (see p. 5). We do not treat these species because they're not really offshore creatures; they can be seen more easily from land. Other marine mammals can be seen from shore on occasion, although to see them up close you'll still want to go out on a boat.

Things to look for with whales and dolphins are group size, general behavior, dorsal fin size and shape, any patterns or markings, and, for the larger whales, shape and size of the blow and how soon the dorsal fin appears relative to when you see the blow.

Whales: Very large swimming creatures 12

Beaked Whales and Pilot Whales: Medium-sized, often in groups 16 Dolphins: Smaller and faster swimming creatures, often in groups 18

Rarer Whales and Dolphins 22

Humpback Whale (HUWH)

The staple of many whale-watching businesses. Fairly common off the Northeast May–Sep, migrating s. to breed in the Caribbean; found off the Southeast mainly in winter. Well-known for active displays at the surface, including tail- and flipper-slapping, breaching, and lunge-feeding. Often seen simply blowing, swimming, and diving (arching its back high but not fluking). With luck or patience, can be seen fluking before deeper dives. Blow bushy, but fairly high. Dorsal fin distinctive but variable, lumpy and fairly low; very long narrow flippers mostly white. Underside of tail varies from white to black; many individuals can be identified by tail pattern.

Whales

Fin (Finback) Whale (FIWH)

Fairly common off the Northeast spring–fall, with a few present in winter; ranges s. to Mid-Atlantic states in late fall–spring; very rarely seen s. of Cape Hatteras. Singly or in small groups; may associate with HUWH in rich feeding areas. Very large and often fast-swimming, with sloping fin typically wider at base than tall, slightly falcate (individually quite variable; cf. much smaller MIWH). Fin appears after blow and after a stretch of back rolls by. Blow taller and stronger than bushier blow of HUWH. Rarely flukes or breaches.

Northern Minke Whale (MIWH)

The Minke (pronounced 'minky') is fairly common off New England spring–fall; very rarely seen to the s. Usually seen singly. Fast-swimming; resembles a mini FIWH but dorsal fin typically taller than wide, often more falcate. Blow low and bushy, usually not striking; fin appears simultaneously with blow, not after a length of back has appeared. Often rolls fairly high but rarely flukes, and after a few blows tends to disappear. Infrequent breaches can be clear out of the water.

North Atlantic Right Whale (RIWH)

Total population only 500 or so animals. Rare to locally uncommon off the Northeast in spring–fall, mainly Apr–early May and late Sep–Nov. Moves s. to winter and calve off the Southeast, Dec–Mar. Found singly or in loose groups, mainly in nearshore waters. Blow bushy and, seen at the right angle, distinctly V-shaped. Large, blackish, and broad-bodied, without dorsal fin; flippers short and broad. Large head has variable whitish patches (callosities). Broad flukes often raised high when sounding.

Sperm Whale, Pilot Whales, and Beaked Whales

Sperm Whale (SPWH)

Uncommon in deeper offshore waters, usually just beyond the shelf break or over submarine canyons; singly or in loose groups. Off New England found mainly late summer–fall, but present year-round to the s. Bushy blow angled forward, not vertical. Dorsal fin low and triangular; massive head apparent at closer range; rear of body wrinkled. Rests at the surface (looks like a giant turd), blowing steadily before sounding for a deep dive, when usually shows its broad, triangular flukes. Feeds on squid in deep water, and dives can last 1–2 hours.

Pilot Whales (PIWH)

2 very similar species of large dolphins, smaller than true whales: Long-finned Pilot Whale and Short-finned Pilot Whale ('long' and 'short' refer to the pectoral flippers, rarely visible). Uncommon to fairly common in deep waters beyond the shelf break. Species identity usually presumed by location and temperature: Long-finned occurs in cooler waters off the Northeast, ranging s. to Mid-Atlantic states in winter; Short-finned in warmer waters off the Southeast, ranging n. to Mid-Atlantic states in summer–fall. Usually in groups of 5–50, often logging at the surface; rarely breach or show flukes. Blackish overall with blunt head. Dorsal fin low and wide-based, lobed at tip on adult male.

Beaked Whales occur in deep waters beyond the shelf break. Found as singles or small groups; often indifferent to boats but at times curious. Surfacing animals show beak first and then a low triangular dorsal fin (similar in all species), but do not fluke; rarely breach. Many sightings are noted simply as 'beaked whale sp.' (= species unidentified).

Cuvier's Beaked Whale (Goosebeak) (CUBW)

Uncommon from Mid-Atlantic states s., very rare n. to Cape Cod. Larger than dolphins, clearly smaller than typical whales. Low bushy blow inconspicuous. Color variable; adults have whitish head, and adult male is marked with whitish scratches. Surfacing animals often show distinctive short 'goosebeak' and roll fairly high, especially before sounding.

Mesoplodon Beaked Whales (MBWH)

The genus Mesoplodon contains numerous similar-looking species worldwide, all slightly smaller than CUBW; 4 occur off the East Coast but are seen infrequently. Usually surface and blow a few times before deep feeding dives. Gervais's Beaked Whale (GEBW) is regular off Cape Hatteras in spring–summer; status and distribution of other species not well known. Photos showing male teeth needed for species identification.

Dolphins

Risso's Dolphin (Grampus) (RIDO)

Uncommon to fairly common from Mid-Atlantic states s., mainly in deeper waters offshore from the shelf break; small numbers range n. to Gulf of Maine in summer–fall. This large dolphin is usually...