Chicago Bird Collision Monitors Rescue Injured Surf Scoter at Montrose Harbor

Bird does not survive due to lead poisoning

Jim Tibensky with the rescued surf scoter

By Annette Prince, Director, Chicago Bird Collision Monitors

The Chicago Bird Collision Monitors (CBCM) were made aware this past November of an injured female surf scoter spotted by CBCM volunteer Chris Williamson. Chris had observed the bird behaving strangely around the harbor docks and noticed that the scoter’s wings were drooping and it seemed unable to fly or dive. The bird appeared to be sickly and was making repeated gaping motions with its mouth and kept its bill open. Unfortunately, these are all symptoms typical of lead poisoning, a major cause of death for waterfowl.

Jim Tibensky, CBCM volunteer and expert kayaker, was summoned to see if he could rescue the bird. He put his boat into the harbor and managed to head the scoter off in an open area where it desperately tried to dive but lacked the wing power to get below the surface of the water. Jim was finally able to collect the bird, and with it safely in his kayak, he paddled back to shore where the bird was placed in a waiting carrier.

The scoter was transported to Willowbrook Wildlife Center in Glen Ellyn, Ill., but unfortunately, it died shortly after being admitted. Veterinarian Dr. Karen Higgs performed a necropsy that revealed the scoter’s gizzard was filled with lead pellets from shotgun ammunition that it had ingested while feeding. Dr. Higgs determined that lead poisoning had brought on neurological damage, convulsions, paralysis and eventually the death of this lovely bird.

The surf scoter's gizzard with lead shot inside during an autopsy.

Efforts to phase out lead shot began in the 1970s, but a nationwide ban on lead shot for all waterfowl hunting in the United States was not implemented until 1991. Canada instituted a complete ban on the use of lead shot in 1999, after restricting its use near bodies of water and in national wildlife areas earlier. Although banned, lead shot remains in the environment where wildlife ingests it while feeding on land or foraging along the bottoms of lakes and ponds.

Surf scoters are diving ducks that spend the summer months in northern Canada and Alaska. Their migration route brings them to the Great Lakes and the Atlantic and Pacific coasts where they spend the winter. It is unknown whether the Montrose Harbor surf scoter ingested the lead shot in the Chicagoland area, or along its migration route.

Many waterfowl eat lead pellets while they are feeding, mistaking them for food like mollusks and clams, or grit – small stones they eat to help grind up food in their gizzards. It can take about three weeks for a bird to die of lead poisoning. Although many thousands of birds probably die each year from lead poisoning, the actual number of birds poisoned by lead is not known. Poisoned birds often hide themselves and die in out-of-the-way places where they are never found. They are also eaten by predators, like bald eagles, and scavengers, like vultures and foxes, which usually leave little trace of their prey. When an animal with lead poisoning is eaten by another animal, the deadly effects move up the food chain to affect the predator in what is called “secondary lead poisoning.”

Ducks, geese, swans and loons are the animals most commonly affected by lead ingestion, however, upland game birds including mourning doves, wild turkeys, pheasants, and quail are occasionally affected. Lead poisoning has also been noted in small mammals (raccoon) and raptors, presumably from the ingestion of lead contaminated prey. In ducks, geese and swans, lead poisoning is most commonly seen during migration in the late fall and early spring. In heavily contaminated areas, cases may be seen at any time of year.

In 1997, Canada banned the use of lead fishing sinkers and jigs weighing less than 50 grams in its national wildlife areas and national parks which may have contributed as much as 3,000 tons of lead to the waterways of the U.S. and Canada each year. The U.S. is also considering a ban on lead fishing sinkers.

CBCM regrets that the surf scoter could not be saved but is very glad the team made such a commendable effort to help this bird. We hope the case of this particular surf scoter can help raise awareness of how an environmental pollutant can produce long-term hazards for wildlife. If you are a hunter or enjoy fishing, please consider the use of non-lead-based shot and sinkers. The extra cost is well worth it.

Chicago Bird Collision Monitors

www.birdmonitors.net