Pd. Vickery et Ml. Hunter, DO ARTIFICIAL SONG-PERCHES AFFECT HABITAT USE BY GRASSLAND BIRDS IN MAINE, The American midland naturalist, 133(1), 1995, pp. 164-169
To test the hypothesis that absence of song-perches limits use of habi
tat by breeding grassland birds, we placed artificial l-m tall song-pe
rches in two experimental plots in Maine. We. found no evidence to sup
port this hypothesis. Although these artificial song-perches were used
frequently as singing perches, species composition and territory dens
ities on these plots were nearly identical to those found on two refer
ence plots. Furthermore, we found no differences in territory densitie
s between species that sing flight-songs and species that sing from fi
xed perches. Our results indicate that: (1) the absence of song-perche
s did not limit grassland birds at this site, and (2) that a variety o
f habitat parameters probably influence the habitat selection process.
Thus, it appears unlikely that the long-term population declines repo
rted for many species of grassland birds in eastern North America can
be mitigated by simple measures such as adding artificial song-perches
to grassland habitats. It is more likely that a variety of factors, p
ossibly on both the breeding and wintering grounds, are involved in th
ese long-term declines.