During the incubation stage of breeding, male House Wrens periodically move very near nest cavities and sing, and females, who alone incubate in this species, often appear to wait to take a break from incubating until they hear their mate singing nearby. This study tested quantitatively for a non-random association between female nest attentiveness and male song output in two ways. First, 11 pairs of wrens were observed for 2 h during their incubation stages and the time of each male song and each female exit from, and entrance into, the nest cavity was noted. Of the 60 exits observed, 29 (48%) occurred within 30 s of when the male began a song bout near the nest. Overall, female exits followed significantly sooner after the start of male song bouts than expected if exits normally occurred at random with respect to song. Males were also removed temporarily from 12 territories during incubation stages and the nest attentiveness of their females was monitored for 2 h. These experimental females spent, on average, 18% more time in nests than did 11 undisturbed control females (47 vs 40 min/h). This occurred only because experimental females waited longer to exit nests during each attentive period. Experimental females did not take shorter recesses. Females may benefit from waiting to exit nests until their mates are singing nearby because: (1) the male's song indicates to the female that no predators are present, (2) males will be present to guard nests, especially against conspecifics, in the female's absence, and/or (3) males can act as sentinels while females are foraging.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Animal Science and Zoology