The avifauna of Myrick Marsh

Abstract

The purpose of this study was to observe the birds of Myrick Marsh in order to determine (1) the species utilizing the marsh as breeders, (2) the transients using the marsh as a resting area, (3) the nonbreeding residents, (4) which species used the marsh as a wintering area and (5) the relative abundance of species observed. Various census routes were established and followed for the duration of the study. Mist nets, funnel traps and Potter traps were used to capture birds for the purpose of banding. A total of 164 individuals belonging to sixteen species were banded. Banding was used to start a long-term project to determine the recurrence of species in the marsh during successive years. Nesting birds were determined by locating singing males, deserted nests and observations of young birds. A total of 150 species were observed with 51 species breeding in the marsh. Of the 150 species, twelve are permanent residents, eighteen winter residents, forty-six transient visitants,forty-three summer residents and thirty-one summer visitants. Three methods were used to determine the relative abundance; Kendeigh, Bond, and number per man-hour. Both the Bond and Kendeigh methods were almost identical in ranking the observed species. Relative abundance varied with the three methods but Red-winged Blackbird (Agelaius phoeniceus) and Tree Sparrow (Spizella arborea) were ranked number one according to each method during the seasons in which these species were dominant. A diversity index was used as a quantitative method in comparing the various seasons. Diversity was dependent on the number of species and individuals observed for each season. Diversity was low during the summer and winter and higher during the spring and fall migrations. A total of fifteen orders were represented with 55.1% of the observed species belonging to the order Passeriformes. A geographical origin of the Myrick Marsh avifauna according to Mayr was also made in order to determine the composition of the avifauna when compared with a different region of the country. The data shows an increase in the number of unanalyzed species as one moves toward the northern latitudes due to increased nesting activity and the presence of more species during the summer.