Sentences with phrase «cicada populations»
Periodical cicada populations are notoriously patchy, far more so than other North American cicada populations,» Marshall says.
https://www.scientificamerican.com/ Not exact matches
«We are basically claiming that, at least indirectly, the cicadas are engineering bird populations and their environments,» Koenig says.
«The cicadas are probably affecting the bird populations in some way — after all, many bird populations use the cicadas as food during emergence years — but I do not think that the patterns in this study prove that the cicadas are inducing delayed bird - population changes that occur 13 or 17 years after emergence,» Marshall concludes.
Bird population crashes seem to correlate with the strange 13 - year and 17 - year cycles of periodical cicadas.
Knowing that researchers in the early 20th century had shown that avian predators can wipe out an entire population of cicadas that emerges out of sequence, Koenig decided to take a look at how bird populations might affect the insects» cycles.
«We still don't have a good theory that explains how the cicadas» resource pulse causes the birds» populations to reach their low point exactly 13 and 17 years later,» Koenig says.
Contrary to what one might expect, these birds» populations drop significantly the year cicadas emerge in all their buzzing glory, the scientists report in the current issue of The American Naturalist.