Holtz, R.E. 1988. A survey of the american bittern at selected wetlands in Washington county. Final report submitted to the Minnesota Department of Natural Resources 12 pp.
A survey of American Bitterns at selected wetlands in Washington County was conducted from 6/7/88 to 6/27/88. Two field researchers listened for bitterns, played taped vocalizations to elicit a response from any birds which might be present, and "chained" a few areas. These observations were made at various times of the day. A network of people who regularly bird Washington County was organized to report any American Bittern observations.
In addition, total bird species counts were taken at twenty sites in Washington County.
The network of birders produced one report of an American Bittern. There were a few other miscellaneous reports.
The search for American Bitterns in Washington County was fruitless. However, the taped vocalization did cause a bittern in another county to fly above the cattails. The chaining technique seems to have limited value.
Literature describing American Bittern habitat and habitat size indicated most of the areas surveyed could be suitable bittern habitat. It was noted that some of the best looking habitat seemed to lack a good supply of bittern food.