Breeding Bird Atlasing takes birding in a slightly different direction than counts. Birders are assigned very specific areas to search for all nesting species. Nesting behavior such as bringing material or food to a possible nest, or observing fledglings ready to fly, must be observed and recorded. Results from across Maryland are compiled and, like with counts, trends can be determined when compared to other data and prior atlas projects. MOS completed two very successful breeding bird atlas projects and is in the initial phases of planning the next effort. MOS published the analysis from the 1983-1987 effort (Atlas of the Breeding Birds of Maryland and the District of Columbia, E.A.T. Blom et al) and the 2002-2006 project (Second Atlas of the Breeding Birds of Maryland and the District of Columbia, ed. Ellison, Walter G). Both volumes may still be available; please check with your favorite booksellers.
Here’s a PBS video about birding and atlasing in our area (beginning at 9:20 minutes into the video).