As you may have noticed, over the past few years, Wonder Lake has experienced a large increase in the population of Double-Crested Cormorants. The presence of these birds in large numbers is believed to have an impact on fish populations. Equally as important is that Cormorants prefer to roost and build nests on islands. Over time, the “droppings” from the roosting Cormorants can build up to the point where they can kill off the trees they roost in.

This is a particular concern as recently over 250 Cormorants have been observed on Strom Island in Wonder Lake, starting to build nests in the large oaks trees found there. With the on-going restoration work being done on Strom Island, it would be a shame to lose these large oaks.

Because Cormorants are a federally protected waterfowl, the MPOA and Wonder Lake Sportsman’s Club have been working with the Illinois Department of Natural Resources on implementing legal means of harassing the Cormorants, to discourage them from roosting and building nests. Often, boat traffic in the vicinity of Strom Island is enough to get the Cormorants to take flight. The challenge has been when boat traffic slows down and the Cormorants come back to the island for the night.

As such, the WLSC will be operating propane cannon in the afternoon and evening to try to discourage the Cormorants. This is a commonly used technique at airports and orchards. This cannon will randomly make a loud noise to scare the Cormorants, but does not fire any kind of projectile or harm the Cormorants. This email is to inform you that you may periodically be hearing something like fireworks going off on Strom Island. The Wonder Lake Police Department, Wonder Lake Fire Department, and the McHenry County Sheriff are all aware of this effort.

We appreciate your cooperation in helping us manage and protect Wonder Lake.