During the winter, Detroit Audubon members Jim Bull and Bruce Szczechowski cut and stacked brush and reworked the surface on protection piers of Wayne County's bridge to Grosse Ile to make more of the area available for nesting of the state threatened common tern. It worked. In 2003, there were 23 nests on the pier; last year there were 60; and this year there were over 180.

Bruce, Jim and several Detroit Audubon volunteers banded over 150 chicks with U.S. Fish and Wildlife Service numbered bands on one leg and color bands on the other so we can tell what year they hatched and what site they were from. In the future, we would like to identify individual terns.

After banding, we often climbed up to the balcony adjacent to the bridge operator's office and observed the terns for an hour or more, taking field notes on their behavior. Of special note on the day we banded the first young: watching one tern make five trips across the river to the area around the DTE Trenton Channel plant, catching a fish each time, bringing it back to feed each of his or her three young, all within six minutes.

Unfortunately, only about 70 chicks fledged (left the nest and were fully on their own). Black-crowned night herons were coming in every night and eating almost all the chicks that hatched during the day. For a while, we stayed around at night to chase off the marauding herons (the adult terns leave the colony at night presumably to avoid these predators so they can live to reproduce later on). We then tried covering the young in the nests with baskets at night. This worked well until chicks started disappearing during the day late in the season. We suspected newly-fledged gulls were the culprits this time. We hope to put a fence around the colony and a rope grid over the top next year that will allow terns to enter but not herons.

The situation on the toll bridge (about two miles north) is worse. That bridge is undergoing repair, and the north crib-which held the most nests in the past-was two-thirds covered with a plastic tarp. While there were 250 nests there last year, only about 30 have squeezed in on the portion of the crib not covered by the tarp. The bridge owner, however, did a nice job of resurfacing the south crib with smaller gravel and added plastic tubes for young to hide from predators and get out of the sun. Both cribs combined had about 110 nests. However, we saw neither chicks nor evidence of eggs hatching at these sites. One possible culprit: fishing in a toxic hot spot in the river. Due to liability issues, the owners have not allowed us on the site. We hope to find a way to resolve their concerns so research can be done to find out why those eggs aren't hatching.

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