Spelling suggestions: "subject:"wird populationsbalansekvation."" "subject:"wird populations.transportation.""
1 |
Modeling Long-Term Changes, 1958-2011, In The Reproduction And Territory Dynamics Of Bald Eagles Of Florida Bay, Southern Coastal EvergladesUnknown Date (has links)
As top-level piscivores, Bald Eagles are a compelling subject for the study of
territory dynamics and are highly representative of the distinctive suite of avian species
that occupy Florida Bay. Despite successful recovery of Bald Eagles (Haliaeetus
leuocephalus) throughout the species range, the population breeding within Florida Bay
has not mirrored this trend. Beginning in the late 1980s, Florida Bay has suffered in its
capacity to support species diversity and abundance as a result of extreme changes in
hydrology related to altered flows of incoming freshwater. In fact, Bald Eagle territory
use in Florida Bay has declined by as much as 43% as year to year variation and
sensitivity to transitions between territory states have increased. Florida Bay’s
populations of other large, conspicuous fish-eating birds, including Ospreys, Great White
Herons, Roseate Spoonbills, and Reddish Egrets each exhibit a similar pattern of decline. The effects of environmental degradation throughout Florida Bay are magnified at higher
trophic levels. The negative trend in territory occupancy is most pronounced in southeast
Florida Bay whereas effects on territory occupancy in the northwest are minimal. The
presence of spatial patterns in territory occupancy, despite regionally available breeding
birds, suggests that individuals are evaluating differences in habitat quality for which
certain territories are no longer considered viable. Building on our current understanding
of the health of this population of Bald Eagles, we have successfully implemented
modeling approaches that identify key territory breeding decisions. Loss of early
breeding season activity (occupied and active territories) despite maintaining high
breeding success indicates that changes in territory dynamics are the result of a failure to
breed and not a reproductive failure. As such, future conservation actions should
promote early breeding season activity (decisions by breeding pairs to initiate nesting) in
areas of Florida Bay that were historically occupied but are now abandoned. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
|
Page generated in 0.1542 seconds