Saturday, April 14, 2012

Starting the Lower Raritan Bird Survey

New Jersey Audubon has been running citizen science surveys in various parts of the state. Some have focused on particular habitats, like surveys of grassland birds and shorebirds, and others have focused on regions of the state. This spring, the organization initiated a breeding bird survey along the Lower Raritan River and its watershed, along with a pilot project to track bird migration in the same area. The goals of the project are to create a baseline of bird population data for the watershed and to identify important bird habitat for future protection. I signed up as a volunteer and picked a set of ten points in Raritan Center, an industrial complex in southern Edison that includes a sizable amount of wild or semi-wild wetland and old field habitat. I had been curious about this site for some time, as it is difficult to find such large tracts of minimally-developed land in this part of the state.

Yesterday I completed the first of the 2-3 migration surveys I will be doing at the site. All of the assigned points are accessible, though noise and obstructed sightlines make two of the points particularly challenging. All ten points are in the area covered by the image above, at more or less even spacing from each other.

There were a lot of birds around, and I recorded about ten species during each of the five-minute point counts. The dominant songbird species was Red-winged Blackbird, which I recorded at eight of the ten points. Other frequently-recorded songbird species included Song Sparrow, American Robin, and American Goldfinch. I also saw quite a lot of gulls – mostly Herring Gulls – in flight overhead. I heard Field Sparrows at three points (at one, unfortunately, after the five minutes was up). That was probably my most interesting finding of the day. Three points along the riverfront produced a Northern Harrier (seen only before my five-minute point count started), a nesting pair of Ospreys (again, seen after the five minutes was over), a Green-winged Teal, and four Boat-tailed Grackles, which I was surprised to see so far upstream. I am looking forward to seeing what other species pass through over the next few weeks.