The pelagic cormorant (Phalacrocorax pelagicus) is a medium-sized marine bird found along the Pacific coast of North America. Identifying pelagic cormorants can be tricky since they look similar to other cormorant species. However, with some key identification tips, you can learn to recognize these striking black and tan colored birds.
Size and Shape
Pelagic cormorants are medium-sized birds, around 24-30 inches (60-75 cm) in length with a wingspan of 39-47 inches (100-120 cm). They have a long neck, small head, short tail, and a slender, streamlined body shape built for diving and swimming underwater in pursuit of fish. Their body profile appears rounded or pot-bellied. When swimming, they ride low in the water with just their neck and head above the surface. The pelagic cormorant’s size and shape differs from larger cormorant species like the great cormorant, and smaller ones like the double-crested cormorant.
Plumage
Adult pelagic cormorants have distinctive black and brown plumage. During breeding season, adults have a blackish head, neck, back and underside. Their flanks appear brownish. The plumage has a bronze iridescent sheen when viewed in direct sunlight. The throat patch has fine white speckling. After breeding season, adults gain white patches on the thighs and scattered white markings on the head and neck. Juveniles are dark brown overall, with a pale tan or white belly. Unlike other cormorants, pelagic cormorants do not have bright orange facial skin. Their eyes are green and feet are black. The combination of dark plumage with tan flank patches helps identify this species.
Range and Habitat
Pelagic cormorants live along the Pacific coastline, breeding from the Aleutian Islands of Alaska down to central Baja California. They spend winters along the Pacific coast from southern Alaska to central Mexico. Look for them in rocky coastal habitats, on offshore islands, and perched on buoys and pilings. Unlike some other cormorants, pelagics do not typically venture far inland or inhabit freshwater habitats.
Flight and Swimming
Pelagic cormorants have a strong, direct flight low over the water’s surface. Their rapid wingbeats alternate with short periods of gliding. When swimming, they propel themselves underwater with their feet. Watch for their slender head and neck sticking up from the water. They often dive from the surface pursue schooling fish. Pelagics do not dive as deeply as some other cormorant species, since their prey is found nearer the surface.
Fishing Behavior
Observing pelagic cormorants’ fishing behavior can help confirm identification. Unlike other cormorants, pelagics do not dive from flight into the water. Rather, they swim along the surface and make shorter dives from a swimming position to catch small schooling fish. Often they work together in groups of two or three birds to herd fish into dense bait balls before diving into the middle of the bait ball to feed.
Vocalizations
Pelagic cormorants are usually silent birds. But at their nesting colonies, they make low grunting or guttural choking sounds. Listen for these grunts and gurgling calls to detect nesting pelagic cormorants. They do not have the wide repertoire of loud croaks, groans or hoarse calls produced by great cormorants.
Nesting Behavior
During breeding season from April to August, look for pelagic cormorants in nesting colonies on coastal cliffs, rocky islands, and offshore sea stacks. Their nests are built on the ground out of sticks, seaweed and guano. Nest sites are very crowded together, with nests stacked on ledges or jumbled together. Parents share incubation duties. Young fledge at 9-10 weeks old and are fed by parents for several more weeks until they become independent.
Key Identification Points
Here are some key points for identifying pelagic cormorants:
- Medium-sized, stocky waterbird with slender neck
- Dark blackish body and wings
- Brownish flank patches
- Fine white neck speckling
- Green eyes
- Swims low in water with thin neck extended
- Forages for fish near surface by diving from swimming position
- Flies low over water with rapid wingbeats
- Grunting or gurgling vocalizations at colonies
- Nests colonially on coastal cliffs and rocky islands
Comparison with Other Cormorant Species
The most likely species to be confused with the pelagic cormorant are:
Double-crested Cormorant
- Larger and bulkier with heavier bill
- Orange facial skin
- Breeds inland on lakes, rivers, swamps
- Often perches with wings spread to dry
Brandt’s Cormorant
- Larger size
- Longer neck
- Blue throat pouch
- No flank patches
- Nested inland or coastally
Great Cormorant
- Much larger size
- Uniformly black plumage
- Heavier bill
- Not found along American Pacific coast
The pelagic cormorant’s combination of medium size, stocky shape, brownish flank patches, speckled neck, and habitat preferences separate it from these other species.
Conclusion
Identifying pelagic cormorants requires paying close attention to details of size, shape, plumage pattern, behavior, habitat, and voice. With practice, birdwatchers can recognize these striking seabirds that inhabit the rocky coastlines and islands along the Pacific coast. Watch for their slim profile swimming low in the water and diving for fish in sync with one another. Listen for gurgling vocalizations near nest sites. Observing key field marks and behaviors will help distinguish the pelagic cormorant from similar cormorant species.