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J.W. Fitzpatrick

Publications and source records attributed to J.W. Fitzpatrick.

6 recordsLinked to original sources

Proactive conservation management of an island-endemic bird species in the face of global change

Biodiversity conservation in an era of global change and scarce funding benefits from approaches that simultaneously solve multiple problems. Here, we discuss conservation management of the island scrub-jay ( Aphelocoma insularis ), the only island-endemic passerine species in the continental United States, which is currently restricted to 250-square-kilometer Santa Cruz Island, California. Although the species is not listed as threatened by state or federal agencies, its viability is nonetheless threatened on multiple fronts. We discuss management actions that could reduce extinction risk, including vaccination, captive propagation, biosecurity measures, and establishing a second free-living population on a neighboring island. Establishing a second population on Santa Rosa Island may have the added benefit of accelerating the restoration and enhancing the resilience of that island's currently highly degraded ecosystem. The proactive management framework for island scrub-jays presented here illustrates how strategies for species protection, ecosystem restoration, and adaptation to and mitigation of climate change can converge into an integrated solution.

California↗

Congruent population structure inferred from dispersal behaviour and intensive genetic surveys of the threatened Florida scrub-jay ( Aphelocoma cœrulescens )

The delimitation of populations, defined as groups of individuals linked by gene flow, is possible by the analysis of genetic markers and also by spatial models based on dispersal probabilities across a landscape. We combined these two complimentary methods to define the spatial pattern of genetic structure among remaining populations of the threatened Florida scrub-jay, a species for which dispersal ability is unusually well-characterized. The range-wide population was intensively censused in the 1990s, and a metapopulation model defined population boundaries based on predicted dispersal-mediated demographic connectivity. We subjected genotypes from more than 1000 individual jays screened at 20 microsatellite loci to two Bayesian clustering methods. We describe a consensus method for identifying common features across many replicated clustering runs. Ten genetically differentiated groups exist across the present-day range of the Florida scrub-jay. These groups are largely consistent with the dispersal-defined metapopulations, which assume very limited dispersal ability. Some genetic groups comprise more than one metapopulation, likely because these genetically similar metapopulations were sundered only recently by habitat alteration. The combined reconstructions of population structure based on genetics and dispersal-mediated demographic connectivity provide a robust depiction of the current genetic and demographic organization of this species, reflecting past and present levels of dispersal among occupied habitat patches. The differentiation of populations into 10 genetic groups adds urgency to management efforts aimed at preserving what remains of genetic variation in this dwindling species, by maintaining viable populations of all genetically differentiated and geographically isolated populations.

Florida↗

Cadmium toxicity among wildlife in the Colorado Rocky Mountains

Cadmium is known to be both extremely toxic and ubiquitous in natural environments. It occurs in almost all soils, surface waters and plants, and it is readily mobilized by human activities such as mining. As a result, cadmium has been named as a potential health threat to wildlife species; however, because it exists most commonly in the environment as a trace constituent, reported incidences of cadmium toxicity are rare. Here we have measured trace metals in the food web and tissues of white-tailed ptarmigan (Lagopus leucurus) in Colorado. Our results suggest that cadmium toxicity may be more common among natural populations of vertebrates than has been appreciated to date and that cadmium toxicity may often go undetected or unrecognized. In addition, our research shows that ingestion of even trace quantities of cadmium can influence not only the physiology and health of individual organisms, but also the demographics and the distribution of species.

Nature↗

The AOU Conservation Committee Review of the biology, status, and management of Cape Sable Seaside Sparrows: Final report

The Cape Sable Seaside Sparrow ( Ammodramus maritimus mirabilis ) was listed as an original member of the federal list of endangered species in 1968. It is restricted to seasonally flooded prairies of extreme southern Florida and is disjunct from all other conspecific breeding populations (Kushlan et al 1982, McDonald 1988). Since the subspecies was described in 1919, its populations have been discovered and rediscovered, often only to disappear or decline to a handful of individuals (Werner and Woolfenden 1983, Kushlan and Bass 1983). Although the sparrow historically is known from six distinct areas, at present only two of these areas support populations numbering in the hundreds or low thousands of individuals. Debates swirl around the status of these remnant populations. The main controversy encompasses whether the sparrow, now largely restricted to Everglades National Park, is in jeopardy of global extinction and if so, what actions must be taken to prevent this from happening. In November 1998, a panel of scientists was assembled under the auspices of the Conservation Committee of the American Ornithologists' Union (AOU) to evaluate the scientific evidence relevant to this controversy. The Panel was charged with scrutinizing the evidence for the existence and probable causes of global population decline in this subspecies, evaluating proposed management actions, and suggesting further research necessary to manage the remaining populations to maximize their chances of long-term persistence. This document presents the conclusions of the Panel, which are based on our reading of the peer-reviewed and “gray” literature, interactions during a workshop held 9 to 11 February 1999 at Florida International University in Miami with researchers investigating the sparrow's biology, and site visits associated with the workshop. In addition, researchers provided the Panel with position papers summarizing their findings and conclusions prior to the workshop and provided information in response to specific questions following the workshop. Further information was obtained through public comment on an initial draft of this report.

The Auk↗

Forty-first supplement to the American Ornithologists' Union Check-list of North American birds

This seventh supplement after the publication of the 6 th edition (1983) of the AOU Check-list of North American Birds includes taxonomic and nomenclatural changes adopted by the Committee on Classification and Nomenclature between 15 March 1995 and 15 March 1997. Because this will be the last supplement before the publication of the 7 th edition of the Check-list , it also summarizes other decisions made by the Committee since 1983 that were not intended to affect the 6 th edition but rather were to lay the foundation for its successor. Most of those decisions relate to sequence or rank of certain taxonomic categories. The Committee believes that compendia such as the Check-list are not appropriate places for the first appearance of novel taxonomic treatments or rearrangements. Therefore, we take the opportunity of this supplement to inform you of the ways in which the 7 th edition will differ from the 6 th . The style of this supplement differs from that of the previous six because they were designed to provide detailed changes to the text in the 6 th edition; this one also is to provide information on how the 7 th edition will differ from the 6 th . Many details on reasons for the change will be discussed in the Preface or text of the new volume.

The Auk↗

A warbler in trouble: Dendroica cerulea

The Cerulean Warbler, like other Neotropical migrants, has suffered extensive loss of breeding habitat during the past century. It differs from many other migrants in its preference for mature floodplain forest with tall trees, a habitat that has become scarce over much of the warbler's original nesting range. Sensitivity to fragmentation within remaining suitable tracts places this warbler at an additional disadvantage. Furthermore, Cerulean Warblers winter strictly in primary, humid evergreen forest along an extremely narrow elevational zone at the base of the Andes. This zone is among the most intensively logged and cultivated regions of the Neotropics. From 1966 to 1987 the Cerulean Warbler showed the most precipitous decline of any North American warbler (3.4% per year). Unless steps are taken to protect large tracts of habitat of this ecologically specialized species, both on the breeding grounds and in the Andean foothills, we believe the future of this warbler is in serious jeopardy.

Book chapter↗