• Weatherhead, Patrick J.
  • Robertson, Raleigh J.


Behavioral tests using freeze-dried female Red-winged Blackbird models were conducted on 11 territorial males through one breeding season. The intensity of courtship in the tests reflected recruitment success but not territory quality, indicating that those male attributes associated with territory establishment differ from those related to female recruitment. A negative correlation was found between recruitment success and territory quality and a possible explanation is presented.


The area chosen for this study was Cow Island Marsh located near the Queen's University Biology Station, 40 km north of Kingston, Ontario. The vegetation of the marsh is predominantly cattail (Typha latifolia), bordered by sweet gale (Myrica gale) and alder (Alnus rugosa). The marsh is approximately 1 ha in area. In order to quantify differences between males, behavioral tests were conducted from the onset of breeding in early May until nesting terminated in late June. Tests were performed between 0900 and 1130 two days a week. A single test consisted of a 5 min presentation of a normally postured, freeze-dried female Red-winged Blackbird to a territorial male. The model was attached to the top of a wooden pole positioned so the model was just above the vegetation, close to the center of a territory to ensure that the behavior recorded was that of the territory holder. To avoid behavior associated with nest defense the model was never placed within 5 m of an active nest. The observer was positioned outside the territory in which the test was conducted, using a portable burlap blind for concealment early in the season and relying on the new growth of vegetation when it became available. The events of the trial were recorded on a portable tape recorder. No male was tested more than once on any given day and the order in which males were tested was varied each day.