Audubon calls for reduction of pesticides due to nest decline

The Connecticut Audubon Society is calling for immediate reductions in the use of pesticides and the creation of man-made nesting sites after an annual report showed a “dramatic decline” of 17 species of birds that nest in Connecticut and eat only insects caught while flying.

The recommendations and action plan are contained in the Connecticut State of the Birds 2013 report, “The Seventh Habitat and the Decline of Our Aerial Insectivores.” The report may be downloaded at

The Connecticut Audubon Society also called for a multi-agency program of research and assessment.

The 17 species, known as aerial insectivores because they eat bugs on the wing, include such birds as Barn Swallows, Whip-poor-wills, Common Nighthawks, Chimney Swifts, Purple Martins, and Tree Swallows.

They are suffering from a long-term population decline that, if unchecked, threatens their survival, according to the Connecticut State of Birds 2013. The report also contains an article about a similar decline in Connecticut’s bat population, which is also entirely reliant on aerial insects.

Aerial insectivores forage in the “seventh habitat” — the relatively unstudied expanse of air above the earth. Billions of insects, arthropods and other bugs inhabit that space in a shifting mass sometimes referred to as aerial plankton (beaches and offshore islands, tidal marshes, shrublands, grasslands, inland wetlands, and forests are the other six).

Connecticut State of the Birds 2013 notes, in an article by Jon McCracken, director of national programs for Bird Studies Canada, that aerial insectivores are still common enough that extinction is unlikely over the next couple of decades.

“But as Jon reports, unless we reverse the trend, population collapse is something of a mathematical certainty,” said Milan Bull, senior director of science and conservation for Connecticut Audubon Society. “The implications will be even more profound if it turns out that the main cause of the collapse is related to changes in aerial plankton.”

Connecticut State of the Birds 2013 was conceived and edited by Bull and by Stephen B. Oresman, chairman emeritus of the Connecticut Audubon Society’s board of directors.

The Connecticut Audubon Society was joined at the release of the report by Susan Whalen, deputy commissioner of the state Department of Energy and Environmental Protection; Kathy Van Der Aue, vice president of the Connecticut Ornithological Association; and Shannon Kearney-McGee, an avian population analyst with the DEEP. Former television host Phil Donahue, who has successfully established Purple Martin colonies on his Westport property, also participated.

Cited as possible causes of the population decline were:

• Fewer man-made nesting sites such as barns, open chimneys and gravel rooftops.

• Loss of open-country foraging habitat.

• Changes in the availability of insects, perhaps because of climate change.

• Exposure to environmental contaminants, including pesticides.

• Reduced availability of dietary calcium because of acid rain.

“Our earlier Connecticut State of the Birds reports were based on well-established research, and we were able to make specific recommendations about protecting forest birds or prioritizing conservation strategies,” said Robert Martinez, president of the Connecticut Audubon Society. “But the lack of research on aerial insectivores means those kinds of recommendations are harder to make this year.”

The report calls on government agencies such as the state Department of Energy and Environmental Protection, academic institutions and conservation organizations to collaborate on a comprehensive assessment of the status of aerial insectivores.

Saying that population decline is most severe throughout the northeastern United States and southeastern Canada, Audubon said the assessment should be undertaken on an interstate and international basis.

In addition, the Connecticut Audubon Society is calling for an increase in aero-ecology research, and greater sharing of research and data through workshops and conferences to improve understanding of the research being conducted, by whom, and what still needs to be accomplished.

In the shorter term, the Connecticut Audubon Society will work with other conservation organizations to help pass pesticide reduction bills in Hartford. In particular, the Connecticut Audubon Society will support a bill to ban the use of pesticides in municipal parks.

The Connecticut Audubon Society will also work with four to six local organizations to create new Purple Martin colonies, a proven method of increasing the number of nest sites. The Connecticut Audubon Society maintains a successful martin colony at its Milford Point Coastal Center and is attempting to establish another at its Stratford Point coastal restoration site.

According to the U.S. Fish and Wildlife Service, significant population declines in the eastern United States have been observed since 1966 in Bank Swallows, Common Nighthawks, Olive-sided Flycatchers, Whip-poor-wills, Chimney Swifts, Eastern Kingbirds, Least Flycatchers, Barn Swallows, Willow-Alder Flycatchers, Purple Martins, and Acadian Flycatchers.

Whip-poor-will, Common Nighthawk, Alder Flycatcher, and Purple Martin are listed as endangered, threatened or of special concern in Connecticut.