CONCORD – New Hampshire Audubon’s Backyard Winter Bird Survey is celebrating 30 years of tracking the state’s winter birds, and biologists need assistance from residents to get a clear picture of what’s really happening with the birds.

The survey will take place Saturday-Sunday, Feb. 11-12.

Anyone can participate by counting the birds in their own backyard on the survey weekend and reporting online or sending the results on a reporting form to New Hampshire Audubon. For a copy of the reporting form and complete instructions, email your name and address to bwbs@nhaudubon.org or call 224-9909. Forms are also available at Audubon centers in Auburn, Concord and Manchester, and online.

For more information about the survey, visit www.nhaudubon.org under Birding.

New Hampshire Audubon initiated a limited survey in 1967 to document the increase of three Southern species: the Northern cardinal, the tufted titmouse and the Northern mockingbird. It was expanded it to include all birds in 1987.

The original Southern species have continued to increase – the Northern cardinal numbers increased from 950 in 1987 to 2,152 in 2016. Several other "Southern" species have followed in the footsteps of those original three.

Why the increases? There is no definitive answer, but most likely it’s some combination of climate change, suburbanization and bird-feeders account for the increases.

– Submitted by N.H. Audubon Society