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Population Biology Commons

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University of Nebraska - Lincoln

2001

Nesting

Articles 1 - 2 of 2

Full-Text Articles in Population Biology

Aspects Of Reproduction And Pair Bonds In Florida Sandhill Cranes, Stephen A. Nesbitt, Martin J. Folk, Stephen T. Schwikert, James A. Schmidt Jan 2001

Aspects Of Reproduction And Pair Bonds In Florida Sandhill Cranes, Stephen A. Nesbitt, Martin J. Folk, Stephen T. Schwikert, James A. Schmidt

Proceedings of the North American Crane Workshop

From 1980-98 we captured and uniquely marked more than 400 Florida sandhill cranes (Grus canadensis prafensis). Age ratios of the marked population, excluding juveniles, was 66% adult and 33% subadult, and the sex ratio was 49% male and 51% female. Average clutch size for 210 nests checked from 1983-97 was 1.78 ± 0.18 (SD) and frequency of l-egg clutches varied among years. Average post-fledging brood size from 1991 to 1997 was 1.27 ± 0.17 (SD), included a 3-chick brood. Average percent ofYOlmg from 2 study areas, 1991-97 was 11.9 ± 3.23 (SD). We observed renesting up to 3 …


An Update Of The Florida Whooping Crane Release Project Through June 2000, Stephen A. Nesbitt, Martin J. Folk, Kathleen A. Sullivan, Stephen T. Schwikert, Marilyn G. Spalding Jan 2001

An Update Of The Florida Whooping Crane Release Project Through June 2000, Stephen A. Nesbitt, Martin J. Folk, Kathleen A. Sullivan, Stephen T. Schwikert, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

Whooping cranes (Grus americana) reared mostly at the USGS Patuxent Wildlife Research Center (patuxent) or the International Crane Foundation (ICF) have been released in Florida in an effort to reestablish a nonmigratory population in the southeastern United States. From 1993 through spring of 2000, we released 208 cranes. Modifications to the release procedure instituted in 1995 have greatly reduced mortality from the initial release period. First year mortality has averaged 50%. A longterm drought that began after spring 1998 may have contnbuted to increased first year mortality in recent years. Most mortality has been from predation, mostly bobcat …