The Connecticut Department of Environmental Protection (DEP), along with Audubon Connecticut and the Connecticut Audubon Society today announced that as part of an overall management plan to protect one of Connecticut's largest heron and egret breeding colonies (rookeries), the small deer population on Charles Island in Milford will soon be removed.
Management of deer on Charles Island is necessary to prevent the loss of nesting habitat used by great and snowy egrets, both state threatened species, and many other state-listed birds such as the glossy ibis. Since Charles Island is closed to hunting and there are no predators on the island, there is no mechanism to naturally control the deer population, leading to starvation.
“After consulting with experts from the Connecticut Audubon Society, Audubon Connecticut, and the Connecticut Agricultural Experiment Station, DEP is taking a science-based approach to evaluate and address threats to bird species on Charles Island,” said Bill Hyatt, Chief of DEP’s Bureau of Natural Resources. “The initial phase of the restoration effort will involve euthanizing the approximately 16 deer currently inhabiting the island. This is necessary to maintain a healthy habitat and prevent the deer from starving. Charles Island is simply not capable of sustaining a deer population.”
Charles Island, a 14-acre wooded island off the coast of Milford near Silver Sands State Park, was designated both a Natural Area Preserve in 1999 and a Long Island Sound Stewardship Site in 2006 by the DEP due to its significant wildlife and coastal resources. This land is accessible at low tide, and over time, deer have wandered onto the island but have not found their way back off, despite the absence of adequate fodder for them.
In addition to the problems caused by deer, many of the mature trees found on the island and relied on by the birds for nesting and raising young are being smothered by oriental bittersweet, a non-native invasive plant. The presence of a fungus that attacks the tree roots, coupled with strong winter storm winds, is having a devastating effect on the perpetuation of the rookery. Immediate implementation of a three-step management plan (invasive species control, habitat restoration, and deer removal) is needed to prevent the rookery from being abandoned by the state-listed birds that have called Charles Island home for decades.
“As one of only 27 Important Birds Areas recognized by Audubon Connecticut, hosting one of the largest nesting colonies of state-threatened herons and egrets, it is a particularly sensitive and important ecological area”, said Tom Baptist, Executive Director of Audubon Connecticut. “The seemingly common herons and egrets we see dotted along our marshes and river banks are threatened in our state and depend on a small handful of nesting colonies like Charles Island to raise their young.”
“This island serves as one of the few remaining breeding colonies of herons and egrets in Connecticut and the overpopulation of white-tailed deer has over-browsed and destroyed the understory, thus degrading the nesting habitat of these wading birds, hindering the regeneration of native vegetation and reducing themselves to a state of starvation,” said Connecticut Audubon Society’s Milan Bull, Senior Director of Science and Conservation. “We support the DEP’s effort to control the deer population on Charles Island in order to protect biodiversity and restore the critical heronry that exists on this 14-acre Natural Area Preserve.”