| hatching asynchrony in burrowing owls is influenced by clutch size and hatching success but not by food. | in most animals, siblings from a given reproductive event emerge over a very short period of time. in contrast, many species of birds hatch their young asynchronously over a period of days or weeks, handicapping last-hatched chicks with an age and size disadvantage. numerous studies have examined the adaptive significance of this atypical hatching pattern, but few have attempted to explain the considerable intrapopulation variation that exists in hatching asynchrony. i explored proximate determi ... | 2005 | 15480800 |
| effectiveness of voluntary habitat stewardship in conserving grassland: case of operation burrowing owl in saskatchewan. | there have been no published performance evaluations of nongovernmental, voluntary habitat stewardship programs. the operation burrowing owl (obo) stewardship program, initiated in 1987, was evaluated for its effectiveness in conservation of grassland habitat during 1986-1993. the 108 obo sites from 1987 to 88 and 98 randomly selected non-obo sites that were grassland in 1986 in the regina-weyburn, saskatchewan study area were classified by size and agricultural soil suitability. by 1993, 41 (38 ... | 2004 | 15037954 |