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FORAGING ECOLOGY OF A WADING BIRD IN TIDALLY INFLUENCED HABITATS: A SEQUENTIAL MODELING FRAMEWORK
Title
FORAGING ECOLOGY OF A WADING BIRD IN TIDALLY INFLUENCED HABITATS: A SEQUENTIAL MODELING FRAMEWORK.
Creator
Martinez, Marisa Takada, Gawlik, Dale E., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
I used empirical data to inform spatially- and temporally-explicit predictions of time-integrated habitat availability (TiHAB), quantify spatiotemporal patterns of resource selection by Little Blue Herons (Egretta caerulea), and evaluate foraging activity as function of resource availability and prey dynamics. Evaluating resource availability over time accounts for the magnitude and duration of resource change. This approach is useful for understanding mechanisms that underlie resource...
Show moreI used empirical data to inform spatially- and temporally-explicit predictions of time-integrated habitat availability (TiHAB), quantify spatiotemporal patterns of resource selection by Little Blue Herons (Egretta caerulea), and evaluate foraging activity as function of resource availability and prey dynamics. Evaluating resource availability over time accounts for the magnitude and duration of resource change. This approach is useful for understanding mechanisms that underlie resource selection in dynamic environments and for guilds that are sensitive to changes in prey availability like wading birds. I found that average TiHAB varied interannually whereby gains and losses in Little Blue Heron foraging habitat at the landscape scale (1-8 km) occurred from slight differences in annual tidal cycles otherwise imperceptible with water depth data alone. Local patterns of resource selection by Little Blue Herons were temporally consistent but spatially variable across tidally influenced environments. TiHAB was the most important habitat attribute over time and space and was superior to other environmental features and prey density as a predictor of Little Blue Heron resource selection. Foraging activity did not show a clear association with probability of resource selection, but foraging metrics were best described by changes in TiHAB consistent with changes in foraging strategy. I conclude that spatiotemporal variation in resource availability reliably predicts patterns of dynamic habitat selection and supports an energy-maximizing foraging strategy for wading birds in tidally influenced habitats. This modeling framework can be applied to quantify the spatiotemporal availability of resources in real-time or under hydrologic restoration regimes and sea level rise scenarios, and track species responses to hydrologic and other environmental fluctuations.
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Date Issued
2022
PURL
http://purl.flvc.org/fau/fd/FA00013925
Subject Headings
Ecology, Herons, Wading birds, Ecological modelling
Format
Document (PDF)
Mathematical modeling of plankton patchiness
Title
Mathematical modeling of plankton patchiness.
Creator
Ather, Simantha S., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
In natural systems, it has been observed that plankton exist in patches rather than in an even distribution across a body of water. However, the mechanisms behind this patchiness are not fully understood. Several previous modeling studies have examined the effects of abiotic and biotic factors on patch structure. Yet these models ignore a key point: zooplankton often undergo diel vertical migration. I have formulated a model that incorporates vertical movement into the Rosezweig-MacArthur (R...
Show moreIn natural systems, it has been observed that plankton exist in patches rather than in an even distribution across a body of water. However, the mechanisms behind this patchiness are not fully understood. Several previous modeling studies have examined the effects of abiotic and biotic factors on patch structure. Yet these models ignore a key point: zooplankton often undergo diel vertical migration. I have formulated a model that incorporates vertical movement into the Rosezweig-MacArthur (R-M) predator-prey model. The R-M model is stable only at a carrying capacity below a critical value. I found that adding vertical movement stabilizes the system even at a high carrying capacity. By analyzing temporal stability and spatial structure, my results show that vertical movement interacts with carrying capacity to determine patch structure.
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Date Issued
2009
PURL
http://purl.flvc.org/FAU/368615
Subject Headings
Marine plankton, Vertical distribution, Marine ecology, Mathematical models, Macroecology, Mathematical models
Format
Document (PDF)
Tidal and long-term volume transport through Jewfish Creek, Florida Keys
Title
Tidal and long-term volume transport through Jewfish Creek, Florida Keys.
Creator
Pitts, Patrick A., Harbor Branch Oceanographic Institute
Date Issued
1998
PURL
http://purl.flvc.org/FCLA/DT/3171648
Subject Headings
Tides --Florida --Biscayne Bay, Hydrodynamics --Mathematical models, Stream measurements, Water --Analysis, Estuarine ecology
Format
Document (PDF)
Transport processes linking shelf and back reef ecosystems in the Exuma Cays, Bahamas
Title
Transport processes linking shelf and back reef ecosystems in the Exuma Cays, Bahamas.
Creator
Smith, Ned P.
Date Issued
2004
PURL
http://purl.flvc.org/FCLA/DT/3171655
Subject Headings
Coral reef ecology --Research, Tides, Ocean currents, Winds, Hydrodynamics --Mathematical models
Format
Document (PDF)
Differentiating decomposition rates within the ridge-slough microtopography of the central Florida Everglades
Title
Differentiating decomposition rates within the ridge-slough microtopography of the central Florida Everglades.
Creator
Van der Heiden, Sheryl R., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
The relative rates of detrital decomposition in four vegetation communities within the Everglades' ridge-slough microtopography were evaluated during two trials. Litterbags with community-specific detritus in proportion to each community's composition were put into the four communities; namely, submerged marsh, emergent marsh, short Cladium ridge, and tall Cladium ridge. These litterbags were paired with litterbags containing control leaf litter from Chrysobalanus icaco and Salix caroliniana...
Show moreThe relative rates of detrital decomposition in four vegetation communities within the Everglades' ridge-slough microtopography were evaluated during two trials. Litterbags with community-specific detritus in proportion to each community's composition were put into the four communities; namely, submerged marsh, emergent marsh, short Cladium ridge, and tall Cladium ridge. These litterbags were paired with litterbags containing control leaf litter from Chrysobalanus icaco and Salix caroliniana during the wet and dry season trials, respectively. No regional differences in decomposition were shown, but there were significant differences across communities, attributed to the initial C:N ratio of the detritus, with the fastest decomposition occurring in the deepest submerged marsh followed by emergent marsh, and the shallower ridge communities had equally slower decomposition. Additionally, both controls followed the same pattern. Thus, decomposition contributes to an active self-maintenance mechanism within the vegetation communities which ultimately helps to conserve the ridges and sloughs.
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Date Issued
2008
PURL
http://purl.flvc.org/FAU/166456
Subject Headings
Biogeochemistry, Surfaces (Technology), Measurement, Vegatation dynamics, Mathematical models, Wetland ecology
Format
Document (PDF)
Lévy flights in Dobe Ju/’hoansi foraging patterns
Title
Lévy flights in Dobe Ju/’hoansi foraging patterns.
Creator
Liebovitch, Larry S., Brown, Clifford T., Glendon, Rachel
Date Issued
2007-02-01
PURL
http://purl.flvc.org/fau/165800
Subject Headings
Hunting and gathering societies--statistical methods, Khoisan (African people), Forage, Human Migration Patterns, Human ecology--Africa, Human settlements--Mathematical models, Search theory
Format
Document (PDF)
comparison of pixel based and object based vegetation community classification in the Arthur R. Marshall Loxahatchee National Wildlife Refuge
Title
A comparison of pixel based and object based vegetation community classification in the Arthur R. Marshall Loxahatchee National Wildlife Refuge.
Creator
Barone, Dorianne M., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
Abstract/Description
Pixel based and object based vegetation community classification methods were performed using 30 meter spatial resolution Landsat satellite imagery of the Arthur R. Marshall Loxahatchee National Wildlife Refuge (Refuge), a remnant of the northern Everglades. Supervised classification procedures using maximum likelihood and parallelepiped algorithms were used to produce thematic maps with the following vegetation communities : wet prairie, sawgrass, cattail, tree island, brush, aquatic/open...
Show morePixel based and object based vegetation community classification methods were performed using 30 meter spatial resolution Landsat satellite imagery of the Arthur R. Marshall Loxahatchee National Wildlife Refuge (Refuge), a remnant of the northern Everglades. Supervised classification procedures using maximum likelihood and parallelepiped algorithms were used to produce thematic maps with the following vegetation communities : wet prairie, sawgrass, cattail, tree island, brush, aquatic/open water. Spectral data, as well as NDVI, texture and principal component data were used to produce vegetation community classification maps. The accuracy levels of the thematic maps produced were calculated and compared to one another. The pixel based approach using the parallelepiped classification algorithm on the spectral and NDVI dataset had the highest accuracy level. A generalized form of this classification using only three vegetation communities (all wet prairie, tree island/brush and aquatic/open water) was compared to a previously published classification which used 1987 SPOT imagery in order to extract information on possible vegetation community transitions that are occurring within the Refuge. Results of the study indicate that 30 meter spatial resolution may be useful for understanding broad vegetation community trends but not species level trends. Pixel based procedures provide a more accurate classification than object based procedures for this landscape when using 30 meter imagery. Lastly, since 1987 there may be a trend of tree island/brush communities replacing wet prairie communities in the northern part of the Refuge and a transition to wet prairie communities in place of tree island/brush communities in the southern portion of the Refuge.
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Date Issued
2008
PURL
http://purl.flvc.org/FAU/58002
Subject Headings
Ecosystem management, Vegetation dynamics, Vegetation classification, Spatial ecology, Mathematical models
Format
Document (PDF)