Dr. Jason Johnston, University of Maine at Presque Isle Assistant Professor of Wildlife Ecology, just had his article published in the journal Behaviour. The article is titled Effects of stage in incubation, time in season, and proportion of original clutch remaining on nest desertion by house sparrows, Passer domesticus.
In the article, Dr. Johnston explains his study of nest desertion in response to clutch reduction by house sparrows. Over two years, he studied 150 nests, 36 of which were deserted, and found that nests were more likely to be deserted when egg reductions occurred earlier in incubation. "This suggests that both time and brood size are used to assess the tradeoff between current and future investment," Johnston said in his article.
He also found that, near the end of the breeding season, the proportion of original clutch eggs remaining and stage in incubation were less important, and that low desertion was likely associated with a lack of re-nesting opportunities during the season.
Whether house sparrows desert or continue investing in a reduced clutch, Dr. Johnston asserts, is a "function of offspring reproductive value when there is an opportunity for re-nesting in the same season." However, he said, near the end of the season, the decision is based on the residual reproductive value of the parents.
According to its website, Behaviour publishes original research pursuing the four questions scientist Niko Tinbergen defined for research in behavioral biology. The editorial board also encourages reviews of behavioral biology that illuminate emergent trends and new directions in behavioral research. Learn more at www.brill.nl/behaviour.