In 1998, hairy prairie-clover was listed as threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and subsequently afforded protection under the Species at Risk Act in 2004. Hairy prairie-clover, being a habitat specialist species confined to areas of sparsely vegetated to bare sand, may provide an indication of the loss of a once viable natural mixed-grass prairie and sand dune landscape indicative to southern Saskatchewan. Therefore, critical habitat identification for hairy prairie-clover is of particular concern, not only to provide conservation efforts for this particular species, but also for bare sand and sand dune environments which are some of the most sensitive landscapes on the prairies. The goal of this thesis is to identify and spatially delineate areas of critical habitat for hairy prairie-clover within the range of a known metapopulation in the Dundurn sand hills south of Saskatoon, Saskatchewan. This research was divided into two specific objectives: 1) to investigate the spatial relationship between bare sand habitat for hairy prairie-clover and other land cover classes, and 2) to study the relationship between habitat configuration and hairy prairie-clover occurrence.<p> To achieve the first objective, the desired output was a land cover classification of the study site at an appropriate spatial and temporal resolution. Wavelet analysis revealed that the optimum spatial resolution for bare sand identification and delineation in the study site was between 2-5 m. Analysis of field spectroradiometer measurements throughout the growing season concluded that the early and late growing seasons were best for spectrally discriminating between land cover classes. A multi-resolution, multi-temporal land cover classification using object-oriented methods resulted in an overall classification accuracy of 79% with a users and producers accuracy of 85% for bare sand. Grassland comprised the matrix of the area covering 45.5% of the study site. Aspen and shrub were the most dominating landscape elements comprising 25.5% and 19.2% of the study site respectively. Bare sand made up only 6.0% of the study site while juniper was the least persistent class comprising only 2.7% of the study site.<p> The desired output from objective two was a critical habitat landscape mosaic for hairy prairie-clover. Patch scaled metrics were calculated for bare sand patches identified in the land cover classification from objective one. Binary logistic regression was used to identify which metrics could explain and predict hairy prairie-clover occurrences. Results showed that almost 29% of the variation in bare sand patch occupancy could be explained by the size, shape, and degree of isolation of a sand patch as well as the amount of vegetation on a sand patch in the early growing season. Based on these variables, 18.8% of sand patches in the study site were predicted to be unsuitable hairy prairie-clover habitat, 45.7% were predicted to be marginally unsuitable, 32.7% were predicted to be suitable, and 2.8% were predicted to be marginally suitable. Overall prediction accuracy was about 61% with 80% of occurrences and 54% of non-occurrences being correctly predicted.

In 1998, hairy prairie-clover was listed as threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and subsequently afforded protection under the Species at Risk Act in 2004. Hairy prairie-clover, being a habitat specialist species confined to areas of sparsely vegetated to bare sand, may provide an indication of the loss of a once viable natural mixed-grass prairie and sand dune landscape indicative to southern Saskatchewan. Therefore, critical habitat identification for hairy prairie-clover is of particular concern, not only to provide conservation efforts for this particular species, but also for bare sand and sand dune environments which are some of the most sensitive landscapes on the prairies. The goal of this thesis is to identify and spatially delineate areas of critical habitat for hairy prairie-clover within the range of a known metapopulation in the Dundurn sand hills south of Saskatoon, Saskatchewan. This research was divided into two specific objectives: 1) to investigate the spatial relationship between bare sand habitat for hairy prairie-clover and other land cover classes, and 2) to study the relationship between habitat configuration and hairy prairie-clover occurrence.<p> To achieve the first objective, the desired output was a land cover classification of the study site at an appropriate spatial and temporal resolution. Wavelet analysis revealed that the optimum spatial resolution for bare sand identification and delineation in the study site was between 2-5 m. Analysis of field spectroradiometer measurements throughout the growing season concluded that the early and late growing seasons were best for spectrally discriminating between land cover classes. A multi-resolution, multi-temporal land cover classification using object-oriented methods resulted in an overall classification accuracy of 79% with a users and producers accuracy of 85% for bare sand. Grassland comprised the matrix of the area covering 45.5% of the study site. Aspen and shrub were the most dominating landscape elements comprising 25.5% and 19.2% of the study site respectively. Bare sand made up only 6.0% of the study site while juniper was the least persistent class comprising only 2.7% of the study site.<p> The desired output from objective two was a critical habitat landscape mosaic for hairy prairie-clover. Patch scaled metrics were calculated for bare sand patches identified in the land cover classification from objective one. Binary logistic regression was used to identify which metrics could explain and predict hairy prairie-clover occurrences. Results showed that almost 29% of the variation in bare sand patch occupancy could be explained by the size, shape, and degree of isolation of a sand patch as well as the amount of vegetation on a sand patch in the early growing season. Based on these variables, 18.8% of sand patches in the study site were predicted to be unsuitable hairy prairie-clover habitat, 45.7% were predicted to be marginally unsuitable, 32.7% were predicted to be suitable, and 2.8% were predicted to be marginally suitable. Overall prediction accuracy was about 61% with 80% of occurrences and 54% of non-occurrences being correctly predicted.

The Hudson River estuary (HRE) is a well monitored aquatic resource and much secondary data exist for this system. We developed two objectives based on accessible HRE aquatic data. The first objective was to determine if changes in HRE fish community over the time period (1974 to 2005) years are correlated to local and regional climate. We addressed this objective by employing a multivariate statistical approach. We confirmed that the HRE fish community structure has changed over the time period (1974 to 2005). These changes are correlated with local hydrology (freshwater flow and water temperature) and regional climate (Atlantic Multidecadal Oscillation or AMO and North Atlantic Oscillation or NAO). We found that abundances of striped bass larval stages are positively correlated with high freshwater flows and juvenile shad abundances are negatively correlated with the AMO or warmer sea surface temperatures (SST). This finding suggests that climate-related variability affects HRE juvenile shad abundances and current management strategies for this declining species should include the implications of climate change. The second objective was to examine whether factors such as sediment type, water characteristics and distance to nearest submerged aquatic vegetation (SAV) beds affect the occurrence or presence/absence of juvenile American shad (Alosa sapidissima) and juvenile striped bass (Morone saxatilis) in the HRE during the fall. We addressed this objective by applying geostatistics and general linear mixed effects models. We found the probability of presence for both species were commonly driven by spatial dependence or river mile, Julian day and salinity. Our results include maps depicting probability of occurrence (or presence) for both species throughout the HRE. We found the highest predicted probabilities of juvenile American shad presence are found in the Upper HRE. Conversely, highest predicted probabilities of juvenile striped bass presence are found in the Lower HRE. Habitat partitioning between these two species is present during the fall in this system but the mechanism is unclear. Future studies could address a possible predator-prey or competitive relationship between juvenile American shad and juvenile striped bass.

Knowledge of species distribution and habitat associations are essential for conservation measures. Such information is lacking for many marine species due to their occupancy of broad and ephemeral habitats that are difficult to access for study. Sea turtles, specifically the surface-pelagic juvenile stage of some species, are a group for which significant knowledge gaps remain surrounding their distribution and habitat use. Recent research has confirmed the long-standing hypothesis that the surface-pelagic juvenile stage occurs within surface-pelagic drift communities (SPDC). Within the North Atlantic and surrounding basins, the holopelagic macroalgae Sargassum spp. dominates SPDC and serves as a remotely-detectable indicator of SPDC. The present study focuses on surface-pelagic habitats of four sea turtle species and addresses knowledge gaps using two approaches: habitat mapping and behavioral examination. Remote sensing techniques were used to identify SPDC, and satellite telemetry to examine behavior. This work was conducted in three parts and is presented in three chapters. Imagery collected from the Landsat satellites (5 and 7) was used to quantify the area of SPDC (km2). Approximately 1,800 Landsat images collected from 2003–2011 were examined for SPDC. The first chapter discusses the abundance, seasonality, and distribution of SPDC within the eastern Gulf of Mexico waters where surface-pelagic green, hawksbill, Kemp’s ridley, and loggerhead turtles are known to occur. SPDC was found year-round within the eastern Gulf of Mexico, and the amount of habitat peaked during summer months. The amount of SPDC within the eastern Gulf of Mexico varied annually with peaks in 2005, 2009, and 2011. High concentrations of SPDC were discovered within offshore waters of the northeastern Gulf of Mexico and southern West Florida Shelf. Within the second chapter, the behavior of 10 surface-pelagic juvenile Kemp’s ridleys was examined using satellite telemetry. Using remotely-sensed imagery, the sea surface habitats used by tracked turtles were examined. Surface-pelagic juveniles are hypothesized to be principally passive drifters. The behavior of tracked turtles was examined to determine if they exhibited periods of active and passive behavior, which may indicate periods of swim and drift. The proximity of tracked turtles to remotely-detected SPDC was examined when coincident Landsat imagery was available (within one day of the turtle’s position). Turtles were tracked for 36.5 days (mean) and exhibited primarily passive behavior during the tracking period. The satellite transmitters messaged frequently and reported temperatures significantly higher than sea surface temperatures. Landsat imagery was available coincident to the tracks of nine individuals. SPDC was present within 74% of images, and the mean distance between tracked turtles and SPDC was 54 km. Close associations between tracked turtles and SPDC were documented for four individuals. Results suggest that the tracked turtles spent a majority of the time drifting within SPDC. The final chapter discusses the density of SPDC within northern and western Gulf of Mexico waters from 2009–2011. Seasonal abundance peaks occurred throughout the study area, but the timing varied. SPDC peaked earlier (late spring) within the northwestern Gulf of Mexico. Moving eastward, the timing of seasonal peaks shifted progressively later during the year. Within the western portions of the study area, SPDC was found to be significantly higher than in the eastern Gulf of Mexico. The eastern Gulf of Mexico may provide critical developmental habitats for several North Atlantic sea turtle species. Additional study is necessary to determine if portions of the western Gulf of Mexico could serve in a similar capacity. SPDC is extremely vulnerable to anthropogenic impacts, specifically oil spills and the occurrence of persistent marine debris. Conservation of SPDC may be challenged by its ephemeral nature; however, the results presented herein could advise conservation efforts (e.g., delineation of critical habitat). The present study described spatial patterns of SPDC occurrence, regions of high abundance, and seasonality. The description of the behavior surface-pelagic sea turtles offers refinements to the spatial distribution of this life stage. These results, coupled with information on circulation patterns and the distribution of sea turtle nesting beaches, can be used to better predict when and where sea turtles and SPDC may be found. For example, the year-round persistence of SPDC within the eastern Gulf of Mexico and the location of major nesting beaches located upstream support the area’s designation as critical habitat for surface-pelagic green, hawksbill, Kemp’s ridley, and loggerhead turtles.

In recent years, critical habitat has been subject to a great deal of controversy and numerous lawsuits. Critical habitat is an integral part of the Endangered Species Act (ESA) that serves not only to protect the species and its habitat but may also help the recovery of the species. Critical habitat has been the subject of a large number of recent lawsuits. These lawsuits arise from conservation groups, forcing the Fish and Wildlife Service (FWS) to designate critical habitat and from developmental groups, claiming that the economic analyses used by the FWS during the designation of critical habitat are faulty. The economic analyses that are currently being done by the FWS are quantifying the costs of critical habitat to the extent possible while virtually making no effort to quantify the benefits of critical habitat. This potentially biased economic analysis can skew public opinion by presenting an unbalanced result from the analysis. Therefore, this thesis presents a methodology for comprehensively identifying and quantifying, where possible, the costs and benefits of critical habitat.

‘Critical Habitat’ is the habitat required to close the life history of an endangered species and is a fundamental requirement for species recovery for two reasons; the role of habitat in population limitation and viability must be determined, and the habitat must be protected. The North Atlantic right whale is an endangered species that annually migrates to the Grand Manan Basin and Roseway Basin Critical Habitats to feed on diapausing calanoid copepods that are typically aggregated at depths of 100 to 150 m. In this thesis I quantify spatial and temporal variation in the copepod prey field and occupancy of right whales in Roseway Basin, and use this information to identify the location and extent of right whale Critical Habitat. To accomplish this, I measured copepod abundance and energy density (kJ m-3) using optical, acoustic and net collection methods during 2007 to 2009. Oceanographic processes that affect variation in the copepod prey field include slope water intrusions, water mass density, gyre-like circulation and frontal features. Aggregations of diapausing copepods are maintained on the southern slope of Roseway Basin by cross-isobath tidal advection, and are advected along-isobath by the residual flow. Tidal advection at a front, coupled with along-isobath advection and shear in the horizontal currents serve to accumulate copepods along the slope where aggregations are maintained for at least 7 days. The abundance, stage-structure, species composition and aggregation locations of copepods, as well as the hydrography and circulation, were variable among the three years of the study. A 20 year time series of right whales, copepods and hydrography revealed that interannual whale occupancy in the Critical Habitats is variable and can be explained by prey field variation only in Roseway Basin. Factors other than the local prey field affect the number of whales that occupy Grand Manan Basin. Variation in the right whale prey field could not be explained by temperature and phytoplankton-dependent growth in the Scotia - Fundy -Gulf of Maine region. The results of this thesis assisted in establishing the Roseway Basin right whale Critical Habitat in 2008, and the cross-disciplinary nature of the study also provides new insights into the relationships between biology and physics in Scotian Shelf - Gulf of Maine basins.

No description available.

Earlier studies have found that endangered species recovery is only weakly associated with the tools enabled by the U.S. Endangered Species Act (ESA). With habitat loss often cited as a leading cause of species declines, we tested whether the recovery of ESA-listed species is instead associated with the protection of critical habitat (CH) by protected areas. We tested the relationship for 299 species using recovery indices derived from the biennial status reports to Congress (1990-2010), as well as NatureServe and IUCN population status data. We found no overall relationship between recovery and the extent to which CH is protected. However, restricting the analysis to recovering species, listed species with larger areas of protected (R2 = 0.158) or strictly protected (R2 = 0.194) CH fared better than species with less protected or strictly protected CH areas. Declining species (199 of 273 species studied) fared no better with more protected habitat. We conclude that the abatement of habitat loss alone does not necessarily facilitate recoveries for the majority of ESA-listed species. We also note that the weak relationships we observed in this study may be reflective of poor recovery status estimates.

Earlier studies have found that endangered species recovery is only weakly associated with the tools enabled by the U.S. Endangered Species Act (ESA). With habitat loss often cited as a leading cause of species declines, we tested whether the recovery of ESA-listed species is instead associated with the protection of critical habitat (CH) by protected areas. We tested the relationship for 299 species using recovery indices derived from the biennial status reports to Congress (1990-2010), as well as NatureServe and IUCN population status data. We found no overall relationship between recovery and the extent to which CH is protected. However, restricting the analysis to recovering species, listed species with larger areas of protected (R2 = 0.158) or strictly protected (R2 = 0.194) CH fared better than species with less protected or strictly protected CH areas. Declining species (199 of 273 species studied) fared no better with more protected habitat. We conclude that the abatement of habitat loss alone does not necessarily facilitate recoveries for the majority of ESA-listed species. We also note that the weak relationships we observed in this study may be reflective of poor recovery status estimates.

With exploding human populations and landscapes that are changing, an increasing number of wildlife species are brought to the brink of extinction. In Canada, the eastern hog-nosed snake, 'Heterodon platirhinos', is found in a limited portion of southern Ontario. Designated as threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), this reptile has been losing its habitat at an alarming rate. Due to the increase in development of southern Ontario, it is crucial to document what limits the snake’s habitat to direct conservation efforts better, for the long-term survival of this species. The goals of this study are: 1) to examine what environmental parameters are linked to the presence of the species at a landscape scale; 2) to predict where the snakes can be found in Ontario through GIS-based habitat suitability models (HSMs); and 3) to assess the role of biotic interactions in HSMs. Three models with high predictive power were employed: Maxent, Boosted Regression Trees (BRTs), and the Genetic Algorithm for Rule-set Production (GARP). Habitat suitability maps were constructed for the eastern hog-nosed snake for its entire Canadian distribution and models were validated with both threshold dependent and independent metrics. Maxent and BRT performed better than GARP and all models predict fewer areas of high suitability when landscape variables are used with current occurrences. Forest density and maximum temperature during the active season were the two variables that contributed the most to models predicting the current distribution of the species. Biotic variables increased the performance of models not by representing a limiting resource, but by representing the inequality of sampling and areas where forest remains. Although habitat suitability models rely on many assumptions, they remain useful in the fields of conservation and landscape management. In addition to help identify critical habitat, HSMs may be used as a tool to better manage land to allow for the survival of species at risk.