Breeding Birds Are Resourceful in Choosing Nest Sites

Northern rough-winged swallow

As the weather warms, birds are busy breeding in the Dyke Marsh Wildlife Preserve.  In April, FODMers observed red-bellied woodpeckers and northern flickers investigating potential nest cavities, despite facing stiff competition from European starlings.  Observers have seen Carolina chickadees and fish crows carrying nesting material in the Belle Haven picnic area and along the Haul Road. 

Northern rough-winged swallows (photo by Ed Eder) are building a nest in the exhaust pipe of a probable derelict boat in the marina. This species claimed this boat’s exhaust as a nest site for the first time in 2011 and has attempted to breed there almost every year since then.  Four swallow species breed in Dyke Marsh: Northern rough-winged swallow, purple martin, tree swallow and barn swallow.  They apparently all rely almost exclusively on human-made nest boxes, structures and even conveyances for their breeding needs. Besides the northern rough-winged swallow’s choice of the boat exhaust, tree swallows used nest boxes and the boom of a sailboat in 2015. 
Purple martins availed themselves of sailboats as well in 2015 and barn swallows built their mud nests under the docks at the marina and under the wooden bridge under the Big Gut. No one documented any swallow species using a natural cavity or nest site during the 2015 survey.  
Breeding activity will continue through August. FODM will conduct our annual breeding bird survey from Memorial Day weekend to July 4, a survey that the organization has done for at least 30 years.