Blog #303 Cayuga’s Snakebird

 Double-crested Cormorant, courtesy of Chad Merda. 

Cayuga Lake is home to many of New York’s most interesting bird species. Of course  Ospreys top the list, followed by Sandhill Cranes, pied-billed grebe, bald eagles, and,  the topic of this blog, the cormorants. The double-crested cormorant, to be more  precise. The double-crested cormorant is named for two small tufts or crests of feathers  on either side of the adult’s head, which is especially vibrant during breeding season. 

These goose-sized birds are considered by many to look like a pre-historic mix between  a goose and loon. Like loons, they have difficulty getting airborne. Cormorants are much  stronger swimmers than they are fliers. Many humans consider them a nuisance by  their sheer numbers, but they are quite stunning if viewed objectively. Their turquoise eyes are set off by yellow-orange facial skin and matte black feathers. 

While commonly seen roosting in tree-top colonies, these fish and crustacean eaters  are expert divers. With webbed feet and sleek bodies built for swimming, they are  skilled opportunists when fishing. Unlike Osprey that make their feathers waterproof by 

preening with uropygial oil, cormorants want their feathers waterlogged. Ospreys are made buoyant by their waterproofed feathers and can only dive to 3 feet below the  surface. Waterlogged cormorants do not have these buoyancy issues and can dive to  depths of 25 feet, but have to dry their wings afterwards in the sun. 

Cormorant’s have solid bodies and dense bones —most birds have hollow bones— which help them sink and dive to the bottom of lakes to hunt. Their webbed feet are also  used to forcefully propel the birds to the lake bottom where they can snag fish and  crustaceans with their hooked bill tips. 

Because their feathers are waterlogged, cormorants swim with just their necks and  heads above water like Anhingas, their cousins in the south. This gives both birds the  nickname of “darters” or “snakebirds.” And like their cousins, cormorants perch in trees  or sit on rocks with their wings open to dry their feathers in the sun. 

Double-crested Cormorants in roost. C.E. Cornell 

Cormorants are not welcomed residents in most communities. Their acidic guano from  their excessive numbers kills vegetation and nest trees and changes soil chemistry. Cormorants also strip the leaves, twigs, and branches off the trees for making their  nests. At times, the weight of the birds and their nests break branches or whole trees. 

Eventually, these roosts will affect the persistence of native plant communities and other  wildlife species that rely on these habitats. 

The proliferation of cormorants is ironic given they were almost completely decimated in  the 1970s. The pesticide DDT and human persecution caused their decline. And now  invasive species are allowing the cormorant populations to explode. 

The cormorants are attracted to Cayuga Lake for two reasons. The invasive zebra and  quagga mussels introduced from Asia have, among other things, increased water clarity in Cayuga Lake. Cormorants are accomplished predators and benefit from clear water.  

The introduction of the round goby was another boon since they are easy prey,  especially in the clearer water. Now, the cormorant populations are responding by  increasing dramatically. 

Double-crested Cormorants on the Niagara River, courtesy of Buffalo News. 

Human folly is at fault for the introduction non-native species. Whether accidental or  intentional, introduction of species has impacts beyond our control. In some communities, the strong odor of cormorant guano near roosts along with the loss of  vegetation, has decreased property values and spoiled waterfront tourist venues.  Cormorants are blamed for overfishing the Niagara River and Lake Erie, taking over the  nesting grounds of common terns on Buffalo’s Outer Harbor, spooking herons and  egrets, and threatening to dismantle millions of dollars’ worth of habitat restoration  efforts. 

Cormorants can clearly become pests when they conflict with humans. Even though  they are protected under the Migratory Bird Treaty Act, the U.S. Fish and Wildlife  Service plans to eliminate more than 50,000 cormorants across 37 states, including  New York.

Double-crested Cormorant or Snakebird swimming with just its head above water. 

The south end of Cayuga Lake has two cormorant roosts that I monitor. One is along  the inlet and in back of the boat house. The second is between the Cargill salt mine and  Ladoga Point in Lansing. Residents on Ladoga Point near the roost don’t complain of  the smell, but they don’t want to lose the trees that block their view of the mine. And  what about Ithaca’s extensive waterfront development? Will the cormorants spoil the  area for tourists or will development push them out?  

Eyes to the sky! 

Candace  

Candace E. Cornell  

Friends of Salt Point  

Lansing, NY  

cec222@gmail.com  

HELP PROTECT OSPREYS! 

• Avoid getting too close to nesting sites during the breeding season. If an animal  vocalizes when you're near, you are too close! Back off Immediately.

• Carry binoculars to view wildlife from afar. 

• Bring a bag and pick up garbage on shorelines.  

• Recycle used fishing line and all materials that can entangle Ospreys, other  birds, and aquatic wildlife.  

• Have fun, but do not release balloons in the wild. Popped balloons are a choking  hazard and the string can strangle Osprey and other wildlife. 

• Help keep local waters clean, healthy, and safe. Volunteer to restore, clean, and  preserve the shorelines. 

• Join the Cayuga Lake Osprey Network and volunteer to help monitor Osprey  nests. If you see any new Osprey or eagle nests, please report them to: Cayuga Lake Osprey Network at cec222@gmail.com. Thank you! 

EYES ON OSPREYS 

WATCH! 

Salt Point Osprey Nest Cam 2021 

READ! 

On Osprey Time—A Blog on the Ospreys of Salt Point 

VISIT! 

Cayuga Lake Osprey Trail