The Submersibles of Carillon Stonegate Pond: Double-crested Cormorants!

Ever walk along the Carillon Stonegate ponds and thought you saw a “duck”, but it was no longer there. Perhaps it was just the sun and shadows playing with your mind. And, yet a minute later, the “duck” reappears!

Cormorant on Carillon Stonegate Pond

It is one of the more unusual birds that frequent our ponds – the Double-crested Cormorant.

Unlike the sky-diving Caspian Terns that we discussed in an earlier blog – diving from high above Carillon Stonegate Pond to its surface, the Cormorant dives from the surface deep into our ponds.

For today’s blog, I have used a variety of sources, including Cornell Lab of Ornithology’s All About Birds and the Audubon Society as a basis for learning. 

COMMON NAME: Double Crested Cormorant

SCIENTIFIC NAME: Phalacrocorax auritus

RESIDENCY: Double-crested Cormorants are the most widespread cormorant in North America, and the one most frequently seen in inland freshwater areas.

Range Map - Birds of North America

HABITAT: Cormorants may be found in almost any aquatic habitat from our seaside coasts to freshwater lakes, rivers, bays and ponds.   Double-crested Cormorants are the primary inland cormorants. These birds also need perching areas such as rocks and trees to rest, dry off and digest their meals. They tend to form breeding colonies and nest in clusters of trees in or near water, on sea cliffs, or on the ground on islands.

Cormorants Pacific Grove CA

WHAT TO LOOK FOR: Here is a description from All About Birds: “the gangly Double-crested Cormorant is a prehistoric-looking, matte-black fishing bird with yellow-orange facial skin”. They have small heads on long, kinked necks. They float low in the water with its thin neck and bill raised and will perch upright on the water with wings half-spread to dry. The cormorant is a little more than two feet long with a wingspan of about four feet. The double-crest of the Double-crested Cormorant is only visible on adults during breeding season.

WHERE AT CARILLON STONEGATE POND: You may sight a cormorant more typically in the Spring and morning. Usually there will be only a single cormorant in the middle of our ponds, diving for fish.

IN-FLIGHT: Unlike ducks, cormorants’ feathers are not very waterproof. While having water resistant feathers protects a bird’s body from getting soaked, this oily coating isn’t great for diving. Cormorants’ feathers instead get waterlogged, allowing the bird to sink and dive more efficiently.  This is thought to be an adaptation that helps cormorants hunt underwater more effectively. Having good wings for swimming, however, comes at a price when flying. Because they have short wings which are perfect to use as rudders, cormorants have the highest energy cost of any flying bird.

DINING MENU: Fish. Therefore, they like the well-stocked fish market at Carillon Stonegate ponds!

HUNTING METHOD: Their fishing technique is impressive: diving and chasing fish underwater propelled by their webbed feet (and sometimes using their wings). Double-crested cormorants can dive to depths of 25 feet. They usually fish in the mid- to upper-tiers of a pond or lake. On Carillon Stonegate pond, our double-crested cormorant diving excursions typically last approximately 30 seconds before they resurface. The tip of a cormorant’s upper bill is shaped like a hook, which is helpful for catching prey.

Cormorant on Carillon Stonegate Pond Hunting

CONSERVATION: Double-crested Cormorant populations have rebounded from hunting and pesticides (DDT) over the past couple centuries, and today they are a widespread and abundant species. Populations increased steadily between 1966 and 2015, according to the North American Breeding bird Survey. The North American Waterbird Conservation Plan estimates a continental population of over 740,000 breeding birds. In the Great Lakes, some cormorant colonies have doubled in periods as short as five years. Some people still regard cormorants as a threat to fishing stocks.

SOUNDS: Double-crested cormorants are mostly silent. All About Birds describes their sounds as “deep, guttural grunts that sound a bit like an oinking pig”. They apparently grunt when taking off or landing.

OTHER FUN FACTS:

• Cormorants are first cousins of the pelicans.
• The name cormorant is derived from the Latin 'corvus marinus', which means 'sea crow.
• The oldest known Double-crested Cormorant was approximately 22 years.
• In 1974, there were only 12 cormorant nests in the state of Illinois; today, the Will County Audubon Society reports that there are over 650 nests just at Lake Renwick Preserve near Plainfield.
• In Asian countries, the cormorant is used to harvest fish. A ring is placed around the bird’s neck so it cannot swallow the fish. The cormorant dives into the water, catches the fish and brings it back to the boat where the handler grabs the fish.
• Some cormorant species can reportedly dive to an astounding depth of 150 feet, which makes them some of the deepest diving birds around.

For more information on Double-crested Cormorants and sources of information used in this blog (these are the sources that I am using to learn as I blog), please visit All About Birds and Audubon Society.  And the Cornell Lab of Ornithology provides a wonderful source of information for anyone interested in learning more about birds.

The Carillon at Stonegate community is very fortunate to have a variety of wetland, forest and prairie environments conducive to a variety of birds and other wildlife. Our community and the Kane County Forest Preserve does an exceptional job in maintaining this natural environment – both for the benefit of the birds and wildlife and for our residents to enjoy. Take a hike and see what you can find – and identify!

And please come back to our blog – “Life on Carillon Stonegate Pond” to learn more about the birds and wildlife that live or visit this wonderful habitat. As I learn, I share with you.