Creature Feature: Cormorant

Combine a goose and a loon, stir in a few prehistoric features, and there you have it – the captivating cormorant. You’ve likely noticed this sleek black deep diver with a snake-like neck frequenting Township waters this time of year. Two species are native to our area. The Double – crested cormorant (Nannopterum auritum) resides year-round while the Neotropic cormorant (Nannopterum brasilianum) visits primarily in the winter.  

Distinguishing between the two can be difficult; there are more similarities than differences. The fact that they flock together makes it even more challenging. Perhaps the easiest tell is the white outlining specific to the head and chin of the adult Neotropic. Bear in mind, juveniles of both species have their own color variations, so if you’re keen on identifying correctly, best to bring along a bird identification guide.  

Neotropic Cormorant
Double-crested cormorant

You’ll find large numbers fishing in local waterways, ponds and lakes. A drive past the south end of Lake Woodlands will almost guarantee a glimpse of a few dozen sunning themselves, wings outstretched.

Cormorants spend most of their time out of the water, resting or holding their wings open to dry. 

Fast Facts 

1. When threatened a Double-crested cormorant may vomit fish at a predator. 

2. The name cormorant is derived from the Latin corvus marinus, which means “sea raven”. Not actually related to ravens, this misnomer likely dates to the Middle Ages when most black birds were referred to as ravens. 

3. The cormorant served as a hood ornament for the Packard automobile brand. (Many people mistakenly believed it to be a swan.) 

Cormorants are pellet-makers. Similar to owls, they spit out pellets that contain bones and scales of the fish they eat. 

What do they eat? 

Primarily fish-eaters, an adult can eat a pound of fish a day. Groups of cormorants work together forming a line as they cross the water, hitting the surface with their wings then take turns diving below to catch fleeing fish. Their long, thin bill has a sharp hook at the end – great for catching small fish. 

Cormorants will also dine on crustaceans, snakes, and amphibians.  

What eats them?  

Most predators are unable to access cormorants easily as they  slip into the water or take flight to escape. If given the opportunity coyotes, alligators, bald eagles and great horned owls will prey on adults and juveniles. Foxes, raccoons, skunks and some birds (crows, jays and grackles) will take advantage of unattended eggs and chicks.   

Why do we need them? 

They play a critical role in nature’s complex food web by helping keep fish, and other aquatic organisms, from overpopulating our waterways. 

And that’s not all 

Cormorants aren’t your average waterbird. Did you know they are uniquely designed to be excellent divers and underwater swimmers. More like a seal than a bird! 

And unlike ducks, cormorants’ feathers are not very waterproof. Instead, their feathers are designed to get waterlogged, allowing these feathery fishermen to sink and dive more efficiently. Their bones also have a higher density than other aquatic avians.   

Double-crested cormorants can dive to depths up to 25 feet and stay underwater for over a minute. Check out the video below and see for yourself just how amazing these birds are at swimming.  

There’s no denying it – cormorants are cool. Next time you’re at a local park with a pond or lake, hopefully you’ll get to experience these fascinating feathered friends yourself.  

Interested in learning more about local wildlife? Check out these past articles: 

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