This study presents 11 years of nesting success and phenology data for Black Swifts (Cypseloides niger) at Box Canyon in Ouray, Colorado. Nest data were recorded on a near-daily basis for 160 nest attempts. Nesting success was 72% and mean and extreme dates of nesting events, including arrival, egg-laying, onset of incubation, hatching, and fledging are reported. On average, Black Swifts arrived on 13 June, egg laying started on 28 June, incubation started on 1 July, hatching occurred on 26 July, and fledging occurred on 13 September. The average incubation period was 26 days and the nestling phase was 48 days. In seven instances, a second egg appeared after loss of the first egg and, in one case, a third egg appeared. It was not possible to ascertain whether second or third eggs represented a renesting attempt or nest usurpation.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 119 • No. 4