Helping Behavior within Sapsuckers (Sphyrapicus spp.)

摘要

I documented interspecific and intra- specific helping behavior (more than two adults feed- ing young at a nest) within sapsuckers of the genus Sphyrapicus. Of 120 nests, 97 belonged to Red-breast- Ed (Sphyrapicus ruber), Red-napd (Sphyrapicus nu- Chalis), or hybrid (Red-breasted × Red-naped) sap- Suckers, and 23 to Williamson's Sapsuckers (Sphyr- Apicus thyroideus). Interspecific helping behavior was Observed at two nests (1 with a Red-breasted × Red- Naped and hybrid female, 1 with Red-breasted × Red- Breasted and Williamson's male) and intraspecific Helping behavior (Red-breasted male) was observed at One nest. Given the rarity of helping behavior observed In these species a functional advantage is unlikely; in- Dividuals that helped might simply have been respond- Ing to a feeding stimulus.