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xi, 124 p. : col. ill. and map. / The Arcata Marsh and Wildlife Sanctuary (AMWS), located on the Humboldt Bay of northwestern California in the town of Arcata, is an excellent example of reciprocity between humans and the natural environment. The AMWS is a constructed wetland ecosystem that works in conjunction with the town's wastewater treatment plant, providing a healthy habitat for birds and other wildlife and a context for the folkloric activity of birding. Interviews with seven local birders at the AMWS and an analysis of the material, economic, biological, social, and spiritual implications of the activity in context serve to support the assertion that reciprocity is an important factor in the sustainability of folkloric interactions between humans and the natural environment. / Committee in charge: Sharon Sherman, Chairperson; Kathryn Lynch, Member; Jill Harrison, Member

This study investigated bird distributions in relation to local habitat and landscape pattern and the implications which habitat fragmentation may have for woodland birds. There were two sections to the research: an experimental study investigating bird gap crossing behaviour across distances of five to 120m; and an observational study modelling woodland bird distributions in relation to local habitat and landscape scale variables in two study areas (East Loch Lomond and the Central Scotland Forest). In the experimental study it was hypothesised that bird willingness to cross gaps will decrease with increasing gap distance even at home-range scales and that the rate of decline will vary interspecifically in relation to bird morphology. Song thrush mobbing calls played at woodland edges in the West of Scotland were used to attract birds across gaps and results were compared with the response along woodland edges. Data were obtained for four species: chaffinch, coal tit, robin and goldcrest. The decline in response with distance across gaps and along woodland edge was modelled for each species using generalized linear modelling. Maximum gap crossing distances ranged from 46m (goldcrest) to 150m (extrapolated value for the chaffinch). Goldcrests responded more readily through woodlands. There was no difference between woodland edge and gap response for the coal tit. Robins and chaffinches however responded more readily across gaps than through woodland. When different response indices were plotted against bird mass and wing area, results suggested that larger birds with bigger wings responded more readily across gaps than through woodland. It is suggested that this relates to differences in bird manoeuvrability within woodlands and ability to evade a predator in gaps. Fragmentation indices were calculated for an area of the Central Scotland Forest to show how willingness to cross different gap distances influences perception of how fragmented the woodlands are in a region. Results are discussed in the context of the creation of Forest Habitat Networks. The data for the observational section of the work was from bird point counts for 200 sample points at East Loch Lomond in 1998 and 2000 and 267 sample points in the Central Scotland Forest in 1999. In addition a time series of point count data was available for 30 sample points at East Loch Lomond. Additional data was gathered for ten sample points (1998) and two sample points (2000) at East Loch Lomond to investigate effects of observer, time and weather on count data. Generalized linear and generalized additive modelling was carried out on these additional data. Results indicated that biases due to the variation in time and weather conditions between counts existed in the pure count data but that these were eliminated by reducing data to presence and absence form for analysis. Species accumulation curves indicated that two counts per sample point were insufficient to determine species richness. However a sufficiently large proportion of the species was being detected consistently in two counts of ten minutes duration for it to be valid to model them in relation to habitat and landscape variables. Point count data for East Loch Lomond in 1998 (ELL98) and the Central Scotland Forest in 1999 (CSF99) for the wren, treecreeper, garden warbler, robin, blue tit, blackbird, willow warbler, coal tit, goldcrest, great tit, and song thrush were analysed using generalized additive modelling. In addition models were built for the blackcap (CSF99) and the siskin, redstart and wood warbler (ELL98). Where all relationships were identified as linear, models were rebuilt as GLMs. Models were evaluated using the Area Under the Curve (AUC) of Receiver Operating Characteristic (ROC) plots. AUC values ranged from 0.84-0.99 for ELL98 and from 0.76-0.93 for CSF99 indicating high predictive accuracy. Habitat variables accounted for the largest proportion of explained variation in all models and could be interpreted in terms of bird nesting and feeding behaviour. However additional variation was explained by landscape scale and fragmentation related (especially edge) variables. ELL98 models were used to predict bird distributions for Loch Lomond in 2000 (ELL00) and for the CSF99. Likewise the CSF99 models were used to predict distributions for ELL98 and ELL00. Predicted distributions had useful application in many cases within the ELL site between years. Fewer cases of useful application arose for predicting distributions between sites. Results are discussed in the context of the generality of bird environment relationships and reasons for low predictive accuracy when models are applied between sites and years. Models which had useful application for ELL00 were used to predict bird distributions for 2025 and 2050 at East Loch Lomond. Habitat and landscape changes were projected based on the proposed management for the site. Since woodland regeneration rates are difficult to predict, two scenarios were modelled, one assuming a modest amount of regeneration and one assuming no regeneration. Predictions derived from the ELL98 models showed broad-leaved species increasing in distribution while coniferous species declined. This was in keeping with the expected changes in the relative extent of broad-leaved and coniferous habitat. However, predictions from the CSF99 models were often less readily explicable. The value of the modelling approach is discussed and suggestions are made for further study to improve confidence in the predictions.

Environmental management agencies make efforts to reduce pollution loading in streams and rivers by promoting vegetated buffer zones between human activity and water. Most of these efforts do not mesh water quality-based buffer zone width requirements with conservation and wildlife values, specifically, the use of these riparian forest corridors for wildlife dispersal between habitats in highly fragmented landscapes. Forest interior birds are of the most concern to management in riparian forests due to their population declines across much of their breeding range. This dissertation investigates the role that landscape-level and habitat-level factors play on the presence of breeding birds in riparian forests, particularly the landscape and habitat factors that are influenced by human-caused fragmentation. This study describes research at the Ray Roberts Greenbelt, Denton, Texas, that explores the relationships between the landscape and forest habitats of the Greenbelt with its breeding bird community. The major findings of this study are that bird communities in the corridor forests are associated with a greater array of factors than are bird communities in patches, suggesting that the birds of patch forests are somewhat insulated from landscape-scale effects. Also, habitat values can be maintained in corridors, but there does not seem to be a significant relationship between the bird communities and the habitat. Forest factors are the primary influences (as inferred from the number of associations and the relative strength of these associations) on the bird communities of the Ray Roberts Greenbelt. Thresholds of richness or abundance in the amount of forest as compared with the forest interior bird community suggest that patches are better than corridors to support this community, and that the more interior forest available, the better for forest interior birds. The suggested minimum amount of forest derived from these thresholds is 35% of the amount of forest within 1 kilometer of any given part of the Greenbelt. Thresholds in forest width for avian communities suggest a minimum width of 200 m for any corridor. Thresholds in distance from interior forest suggest that the forest interior bird community can be best supported by shorter corridors that connect larger patches, with a suggested maximum corridor length of 125 m.

In south Florida, the Greater Everglades ecosystem supports sixteen species of wading birds. Wading birds serve as important indicator species because they are highly mobile, demonstrate flexible habitat selection, and respond quickly to changes in habitat quality. Models that establish habitat relationships from distribution patterns of wading birds can be used to predict changes in habitat quality that may result from restoration and climate change. I developed spatio-temporal species distribution models for the Great Egret, White Ibis, and Wood Stork over a decadal gradient of environmental conditions to identify factors that link habitat availability to habitat use (i.e., habitat selection), habitat use to species abundance, and species abundance (over multiple scales) to nesting effort and success. Hydrological variables (depth, recession rate, days since drydown, reversal, and hydroperiod) over multiple temporal scales and with existing links to wading bird responses were used as proxies for landscape processes that influence prey availability (i.e., resources). In temporal foraging conditions (TFC) models, species demonstrated conditional preferences for resources based on resource levels at differing temporal scales. Wading bird abundance was highest when prey production from optimal periods of wetland inundation was concentrated in shallow depths. Similar responses were observed in spatial foraging conditions (SFC) models predicting spatial occurrence over time, accounting for spatial autocorrelation. The TFC index represents conditions within suitable depths that change daily and reflects patch quality, whereas the SFC index spatially represents suitability of all cells and reflects daily landscape patch abundance. I linked these indices to responses at the nest initiation and nest provisioning breeding phases from 1993-2013. The timing of increases and overall magnitude of resource pulses predicted by the TFC in March and April were strongly linked to breeding responses by all species. Great Egret nesting effort and success were higher with increases in conspecific attraction (i.e., clustering). Wood Stork nesting effort was closely related to timing of concurrently high levels of patch quality (regional scale) and abundance (400-m scale), indicating the importance of a multi-scaled approach. The models helped identify positive and negative changes to multi-annual resource pulses from hydrological restoration and climate change scenarios, respectively. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

Cattle grazing in riparian zones can have large impacts on vegetation characteristics and avian biodiversity. To assess these impacts in southern Alberta, vegetation and bird surveys were conducted in twelve riparian sites (four each in heavily grazed, moderately grazed, and ungrazed habitats) along the Oldman River. The shrub understory and bird species diversity and abundance declined significantly as grazing intensity increased. Settlement patterns, territory sizes, and food provisioning rates of some bird species were examined to assess the mechanisms behind this reduction. Five out of seven species settled earlier in ungrazed habitats, whereas two species did not show any discernable settlement pattern. The territory sizes of three species examined increased as grazing intensity increased. House wrens (Troglodytes aedon) brought more food and more food biomass to their nests in ungrazed habitats. These results indicate that available food biomass decreased as grazing intensity increased, and is an important factor in population dynamics of some species. / 29 cm.

The forest avian community of the Ray Roberts Greenbelt (Denton Co., Texas) was characterized for two years using point count station sampling, from fall 1998 to summer 2000. Richness data for both breeding seasons were correlated with two-spatial metrics: width of the riparian forest and distance to the nearest edge. There were significant correlations between forest interior species richness and both spatial metrics, for both breeding seasons. Based on these data, a minimum riparian forest width threshold of 400-meters is suggested to provide habitat for forest interior species, which have lost considerable habitat through forest fragmentation. Partners in Flight breeding bird priority concern scores were used to create a habitat priority index for the Trinity River bottomland hardwood forest system

The Wattled Crane, Bugeranus carunculatus Gmelin, is presently classified as being 'Critically Endangered' within South Africa according to the Eskom Red Data book of Birds of South Africa, Lesotho and Swaziland, with a population of a meagre 235 individuals. Of this, 85% occur within KwaZulu-Natal and live predominantly on privately owned agricultural land. As a result thereof, Wattled Cranes and agriculture compete for the same resources. Up until now, the loss of viable habitat, as a result of agricultural development and afforestation, has been mooted as being the primary reason for the decline in numbers of the species. The advancements in the Geographical Information Systems field have enabled conservationists to acquire data, especially pertaining to habitat requirements, which were previously unattainable. This improved data acquisition is enabling for more informed decision making and better allocation of resources. The study therefore attempts to make use of a Geographical Information System to determine whether or not differences exist within the home ranges of active and historical Wattled Crane nesting sites, utilising the National Land cover database. The updated Land cover data for South Africa, although not completed at the time the present study took place, allowed for the interrogation of the various Land cover classes within an estimated home range. Natural Grassland was the predominant Land cover type within both active and historical home ranges, whilst both active and historical home ranges were subject to some degree of transformation. The potential impact of management practices in and around nesting sites warrants further investigation because this could not be determined through the analysis of land cover. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.