This devil pictured today is basically a black bird with an orange throat and lore (the area between its eyes and its bill). Its weight runs from three to five pounds and it has a wingspan of about 4.5 feet. Its bill is hooked, it has blue-greenish eyes and its dives for its food: fish.
The cormorant is native but in the 1960s its numbers began to decline due to the effects of DDT (weakening of the egg shells). After DDT was banned in 1972 the population began to rise again. Since the early 1990s there has been a dramatic population explosion, which is attributed to a combination of factors: reduced human persecution, declining levels of chlorine contaminants and an abundance of forage-base fish, notably alewife. Cormorants generally don't breed until they are 3 years old and then they have three or four eggs each year and can live for up to 25 years.
Recently I have been receiving a lot of emails and calls about the numbers of these black devils that folks are seeing along Lake Ontario and in private ponds. I also have noticed a big increase of them (including nesting) in the Alabama swamp over the past few years.
The problem with cormorants is twofold.
First, they eat an average one pound of fish per day — they're capable of taking up to a 12-inch fish — so, in the swamp, they take a lot of fish that are needed by ospreys, eagles, terns, herons, egrets and other wetland birds that depend on small fish and other aquatic animals. They gobble up the stocks of fingerling salmon and trout in Lake Ontario, thus taking away the growth of that fishing enterprise, which the state is trying to promote. With their numbers growing, this is becoming a serious problem.
The second problem is their excrement. This stuff not only really stinks, it kills off the trees and vegetation below their roosting and nesting areas because of the concentration. They quickly destroy the environment where they congregate. I have seen small islands in the St. Lawrence River “white washed” with their excrement and all vegetation killed.
Cormorants are protected by the Migratory Bird Treaty Act but depredation permits were provided to individuals, private organizations, federal and state agencies, allowing lethal control on a case-by-case basis when populations increased and started causing problems. However, in May of 2016, the U.S. District Court stopped the depredation orders until the National Fish and Wildlife Service could prepare an adequate environmental impact statement. So here we go — long studies and thus the slow coming of solutions, thanks to “do-gooders” who have no clue what is going on because of this bird.
There have been permits issued to harass cormorants from places (move them to cause problems in other locations) and there have been some lethal methods applied but not enough and it is not working.
These birds will travel 40 miles from feeding areas to roost areas or to nest in colonies. My concern is for the local wildlife refuge and the state Wildlife Management areas, as cormorants are already nesting, more than most realize, in the large great blue heron colony on the Iroquois refuge (where we also have nesting great egrets) and many are roosting in the Oak Orchard and Tonawanda management areas.
Besides the excrement problem, how many fish do cormorants really take? Let's just say one pair taking 2 pounds a day over a life span of 15 to 20 years really adds up (around 15,000 pounds) — but the main problem is that their reproduction has skyrocketed, which will keep compounding the problems.
The breeding population of cormorants increased slowly from initial colonization in 1913-1920 to about 1950, despite persecution. Then reproductive failure caused by DDT led to their virtual extinction on the Great Lakes by the early 1970s. Since then, the population has increased dramatically, at an average rate of 29% per year. Since the early 1990s there has been a dramatic population explosion, which is attributed to a combination of factors: reduced, declining levels of chlorine contaminants; an abundant increase of forage-base fish; and very little persecution.
Personally I think it's going to take a big population crash (diseases) of these blue-eyed devils to solve the compounding problem, which will unfortunately probably affect other wildlife.
Doug Domedion, outdoorsman and nature photographer, resides in Medina. Contact him at (585) 798-4022 or email@example.com .