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At least 523 records · Page 29Linked to original sources

USGS2015

Anatomy of an eradication effort: Removing Hawaii's illegally introduced axis deer

In February 2011, a rancher in the rural southern part of Hawaii Island reported a large mammal on her land. Her call mobilized several agencies led by the Big Island Invasive Species Committee (BIISC), a partnership to prevent, detect, and control the establishment and spread of invasive species, to sit up and take notice. Agency biologists installed camera traps to identify the animal, and a few months later verified the diagnostic field marks of a chervid with spots. The animal in questions was a chital , or axis deer ( Axis axis )--a species native to tropical and subtropical India. Although the deer are abundant on the islands of Molokai, Lānai, and Maui, officials knew they weren't capable of swimming across the notoriously treacherous ʻAlenuihāhā channel, and subsequently suspected human intervention. Soon after the rancher's report, the U.S. Fish and Wildlife Service launched an investigation, which revealed that in December 2009, a helicopter pilot and rancher from Maui had covertly transported four deer in exchange for about a dozen European mouflon sheep ( Ovis gmelini musimon ) (Tummons 2011a, b)--a species also valued for trophies and meat. Because neither species was established in the wild on either of the islands, in June 2012, state lawmakers responded by specifically banning "the international possession or interisland transportation or release of wild or feral deer" (Honolulu Star-Advertiser 2012). The two individuals were prosecuted under the Lacey Act for transporting wildlife between islands with the intent to guide hunting for out-of-state residents (Stephens Media 2012), while the individual who provided the mouflon was sentenced to community service. Further, the helicopter pilot agreed to provide 500 hours of flight time to locate and eradicate the Hawaii Island deer population in restitution.

Hawai'i↗

USGS2011

Perceptions of fish habitat conditions in Oklahoma tailwater fisheries: a survey of fisheries managers

While the downstream effects of dams on fish habitat have long been recognized, broad-scale assessments of tailwater fish habitat have rarely been conducted. In this paper, I report on the status of tailwater fisheries in Oklahoma as determined through a web-based survey of fisheries biologists with the Oklahoma Department of Wildlife Conservation conducted in July 2010. Respondents addressed 38 tailwaters, encompassing all major areas of the state. The majority of fish species comprising these fisheries included blue catfish (Ictalurus furcatus), followed by white bass (Morone chrysops), channel catfish (I. punctatus) and flathead catfish (Pylodictis olivaris). Most respondents indicated no or low concerns with fish habitat in tailwaters under their management supervision; only two tailwaters (Tenkiller Ferry and Fort Gibson) had the majority of concerns with fish habitat identified as high to moderately high. Principal components analysis and subsequent correlation analysis showed that tailwaters that scored high for issues related to shoreline erosion, change in water depth, flow fluctuations, and flow timing were associated with dams with large maximum discharge ability. No other factors related to fish habitat condition in tailwaters were found. In Oklahoma, dams with maximum discharge of at least 6,767.5 m3 sec–1 were more likely to have flow-related fish habitat concerns in the tailwater.

Proceedings of the Southeastern Association of Fis↗

USGS2012

A fine-scale assessment of using barriers to conserve native stream salmonids: a case study in Akokala Creek, Glacier National Park, USA

Biologists are often faced with the difficult decision in managing native salmonids of where and when to install barriers as a conservation action to prevent upstream invasion of nonnative fishes. However, fine-scale approaches to assess long-term persistence of populations within streams and watersheds chosen for isolation management are often lacking. We employed a spatially-explicit approach to evaluate stream habitat conditions, relative abundance, and genetic diversity of native westslope cutthroat trout (Oncorhynchus clarkii lewisi) within the Akokala Creek watershed in Glacier National Park- a population threatened by introgressive hybridization with nonnative rainbow trout (O. mykiss) from nearby sources. The systematic survey of 24 stream reaches showed broad overlap in fish population and suitable habitat characteristics among reaches and no natural barriers to fish migration were found. Analysis of population structure using 16 microsatellite loci showed modest amounts of genetic diversity among reaches, and that fish from Long Bow Creek were the only moderately distinct genetic group. We then used this information to assess the potential impacts of three barrier placement scenarios on long-term population persistence and genetic diversity. The two barrier placement scenarios in headwater areas generally failed to meet general persistence criteria for minimum population size (2,500 individuals, Ne = 500), maintenance of long-term genetic diversity (He), and no population subdivision. Conversely, placing a barrier near the stream mouth and selectively passing non-hybridized, migratory spawners entering Akokala Creek met all persistence criteria and may offer the best option to conserve native trout populations and life history diversity. Systematic, fine-scale stream habitat, fish distribution, and genetic assessments in streams chosen for barrier installation are needed in conjunction with broader scale assessments to understand the potential impacts of using barriers for conservation of native salmonid populations threatened by nonnative fish invasions.

Open Fish Science Journal↗

USGS2012

Identifying the decision to be supported: a review of papers from environmental modelling and software

Two of the basic tenets of decision support system efforts are to help identify and structure the decisions to be supported, and to then provide analysis in how those decisions might be best made. One example from wetland management would be that wildlife biologists must decide when to draw down water levels to optimise aquatic invertebrates as food for breeding ducks. Once such a decision is identified, a system or tool to help them make that decision in the face of current and projected climate conditions could be developed. We examined a random sample of 100 papers published from 2001-2011 in Environmental Modelling and Software that used the phrase “decision support system” or “decision support tool”, and which are characteristic of different sectors. In our review, 41% of the systems and tools related to the water resources sector, 34% were related to agriculture, and 22% to the conservation of fish, wildlife, and protected area management. Only 60% of the papers were deemed to be reporting on DSS. This was based on the papers reviewed not having directly identified a specific decision to be supported. We also report on the techniques that were used to identify the decisions, such as formal survey, focus group, expert opinion, or sole judgment of the author(s). The primary underlying modelling system, e.g., expert system, agent based model, Bayesian belief network, geographical information system (GIS), and the like was categorised next. Finally, since decision support typically should target some aspect of unstructured decisions, we subjectively determined to what degree this was the case. In only 23% of the papers reviewed, did the system appear to tackle unstructured decisions. This knowledge should be useful in helping workers in the field develop more effective systems and tools, especially by being exposed to the approaches in different, but related, disciplines. We propose that a standard blueprint for reporting on DSS be developed for consideration by journal editors to aid them in filtering papers that use the term, “decision support”.

Leipzig↗

USGS2012

Contributions of Arctic PRISM to monitoring western hemispheric shorebirds

Long-term monitoring of populations is of paramount importance to understanding responses oforganisms to global environmental change and to evaluating whether conservation practices are yielding intended results through time (Wiens 2009). The population status of many shorebird species, the focus of this volume, remain poorly known. Long-distance migrant shorebirds have proven particularly difficult to monitor, in part because of their highly migratory nature and ranges that extend into highly inaccessible regions. As migrant shorebirds travel the length of the hemisphere, they congregate and disperse in ways that vary among species, locations, and years, presenting serious challenges to designing and implementing monitoring programs. Rigorous field and quantitative methods that estimate population size and monitor trends are vitally needed to direct and evaluate effective conservation measures. Many management efforts depend on unbiased population size estimates; for example, the shorebird conservation plans for both Canada and the United States seek to restore populations to levels calculated for the 1970s based on the best information available from existing surveys. Further, federal wildlife agencies within the United States and Canada have mandates to understand the state of their nations' resources under various conventions for the protection of migratory birds. Accurate estimates of population size are vital statistics for a variety of conservation activities, such as prioritizing species for conservation action and setting management targets. Areas of essential habitat, such as those designated under the Western Hemisphere Shorebird Reserve Network, the Important Bird Areas program of BirdLife International and the National Audubon Society, or Canada's National Wildlife Areas program, are all evaluated on the basis ofproportions of species' populations which they contain. The size, and trends in size, ofa species' population are considered key information for assessing its vulnerability and subsequent listing under the U.S. Endangered Species Act and the Canadian Species at Risk Act. To meet the need for information on population size and trends, shorebird biologists from Canada and the United States proposed a shared blueprint for shorebird monitoring across the Western Hemisphere in the late 1990s; this effort was undertaken in concert with the development of the Canadian and U.S. Shorebird Conservation Plans (Donaldson et al. 2000, Brown et aL 2001). Soon thereafter, partners in the monitoring effort adopted the name "Program for Regional and International Shorebird Monitoring" (PRISM). Among the primary objectives of PRISM were to estimate the population sizes and trends of breeding North American shorebirds and describe their distributions (Bart et al. 2002). PRISM members evaluated ongoing and potential monitoring approaches to address 74 taxa (including subspecies) and proposed a combination of arctic andboreal breeding surveys, temperate breeding and non-breeding surveys, and neotropical surveys.

Book chapter↗

USGS2012

Use of acoustic telemetry to evaluate survival and behavior of juvenile salmonids at hydroelectric dams: A case study from Rocky Reach Dam, Columbia River, USA: Chapter 8.1

Telemetry provides a powerful and flexible tool for studying fish and other aquatic animals, and its use has become increasingly commonplace. However, telemetry is gear intensive and typically requires more specialized knowledge and training than many other field techniques. As with other scientific methods, collecting good data is dependent on an understanding of the underlying principles behind the approach, knowing how to use the equipment and techniques properly, and recognizing what to do with the data collected. This book provides a road map for using telemetry to study aquatic animals, and provides the basic information needed to plan, implement, and conduct a telemetry study under field conditions. Topics include acoustic or radio telemetry study design, tag implantation techniques, radio and acoustic telemetry principles and case studies, and data management and analysis. Chapters are written by biologists, technicians, and engineers from the private, academic, and government sectors, with decades of experience using these technologies.

Washington↗

USGS2011

Use of large-scale, multi-species surveys to monitor gyrfalcon and ptarmigan populations

We evaluated the ability of three large-scale, multi-species surveys in the Arctic to provide information on abundance and habitat relationships of Gyrfalcons ( Falco rusticolus ) and ptarmigan. The Program for Regional and International Shorebird Monitoring (PRISM) has surveyed birds widely across the arctic regions of Canada and Alaska since 2001. The Arctic Coastal Plain survey has collected abundance information on the North Slope of Alaska using fixed-wing aircraft since 1992. The Northwest Territories-Nunavut Bird Checklist has collected presence-absence information from little-known locations in northern Canada since 1995. All three surveys provide extensive information on Willow Ptarmigan (Lagopus lagopus) and Rock Ptarmigan (L. muta). For example, they show that ptarmigan are most abundant in western Alaska, next most abundant in northern Alaska and northwest Canada, and least abundant in the Canadian Archipelago. PRISM surveys were less successful in detecting Gyrfalcons, and the Arctic Coastal Plain Survey is largely outside the Gyrfalcon's breeding range. The Checklist Survey, however, reflects the expansive Gyrfalcon range in Canada. We suggest that collaboration by Gyrfalcon and ptarmigan biologists with the organizers of large scale surveys like the ones we investigated provides an opportunity for obtaining useful information on these species and their environment across large areas.

Alaska, Northern Canada↗

USGS2015

Final project memorandum: sea-level rise modeling handbook: resource guide for resource managers, engineers, and scientists

Coastal wetlands of the Southeastern United States are undergoing retreat and migration from increasing tidal inundation and saltwater intrusion attributed to climate variability and sea-level rise. Much of the literature describing potential sea-level rise projections and modeling predictions are found in peer-reviewed academic journals or government technical reports largely suited to reading by other Ph.D. scientists who are more familiar or engaged in the climate change debate. Various sea-level rise and coastal wetland models have been developed and applied of different designs and scales of spatial and temporal complexity for predicting habitat and environmental change that have not heretofore been synthesized to aid natural resource managers of their utility and limitations. Training sessions were conducted with Federal land managers with U.S. Fish and Wildlife Service, National Park Service, and NOAA National Estuarine Research Reserves as well as state partners and nongovernmental organizations across the northern Gulf Coast from Florida to Texas to educate and to evaluate user needs and understanding of concepts, data, and modeling tools for projecting sea-level rise and its impact on coastal habitats and wildlife. As a result, this handbook was constructed from these training and feedback sessions with coastal managers and biologists of published decision-support tools and simulation models for sea-level rise and climate change assessments. A simplified tabular context was developed listing the various kinds of decision-support tools and ecological models along with criteria to distinguish the source, scale, and quality of information input and geographic data sets, physical and biological constraints and relationships, datum characteristics of water and land elevation components, utility options for setting sea-level rise and climate change scenarios, and ease or difficulty of storing, displaying, or interpreting model output. The handbook is designed to be a primer to understanding sea-level rise and a practical synthesis of the current state of knowledge and modeling tools as a resource guide for DOl land management needs and facilitating Landscape Conservation Cooperative (LCC) research and conservation initiatives.

Conference Paper↗

USGS2005

Coral disease and health workshop: Coral histopathology II, July 12-14, 2005

The health and continued existence of coral reef ecosystems are threatened by an increasing array of environmental and anthropogenic impacts. Coral disease is one of the prominent causes of increased mortality among reefs globally, particularly in the Caribbean. Although over 40 different coral diseases and syndromes have been reported worldwide, only a few etiological agents have been confirmed; most pathogens remain unknown and the dynamics of disease transmission, pathogenicity and mortality are not understood. Causal relationships have been documented for only a few of the coral diseases, while new syndromes continue to emerge. Extensive field observations by coral biologists have provided substantial documentation of a plethora of new pathologies, but our understanding, however, has been limited to descriptions of gross lesions with names reflecting these observations (e.g., black band, white band, dark spot). To determine etiology, we must equip coral diseases scientists with basic biomedical knowledge and specialized training in areas such as histology, cell biology and pathology. Only through combining descriptive science with mechanistic science and employing the synthesis epizootiology provides will we be able to gain insight into causation and become equipped to handle the pending crisis. One of the critical challenges faced by coral disease researchers is to establish a framework to systematically study coral pathologies drawing from the field of diagnostic medicine and pathology and using generally accepted nomenclature. This process began in April 2004, with a workshop titled Coral Disease and Health Workshop: Developing Diagnostic Criteria co-convened by the Coral Disease and Health Consortium (CDHC), a working group organized under the auspices of the U.S. Coral Reef Task Force, and the International Registry for Coral Pathology (IRCP). The workshop was hosted by the U.S. Geological Survey, National Wildlife Health Center (NWHC) in Madison, Wisconsin and was focused on gross morphology and disease signs observed in the field. A resounding recommendation from the histopathologists participating in the workshop was the urgent need to develop diagnostic criteria that are suitable to move from gross observations to morphological diagnoses based on evaluation of microscopic anatomy. As a continuation of building the foundation and framework for coral disease diagnostics, the CDHC convened the Coral Disease and Health Workshop: Coral Histopathology II in Charleston, South Carolina, July 11-14, 2005. The workshop was hosted by the Department of Pathology and Laboratory Medicine at the Medical University of South Carolina, Charleston, SC which provided expertise, facilities and equipment in support of the workshop. All of the histological slides and related photographs used in the discussions were prepared and supplied by the IRCP. This workshop brought together 15 experts in veterinary and medical pathology and coral biology from national and international research institutes and government laboratories. The mission was to devise a standardized approach to examining microscopic anatomy and pathology of corals and a standardized nomenclature to facilitate accurate descriptions of the microscopic morphology of corals and enhance communication among specialists investigating causes of coral death. 2 The participants of this workshop deliberated for 3 days to refine the nomenclature for gross and microscopic anatomy of corals and systematically described microscopic changes associated with selected coral diseases. The findings and recommendations from the deliberations will be submitted to the research community for peer review. The standardized nomenclature and descriptions produced at this workshop will ultimately be made available to the scientific community through a variety of media including the World Wide Web. An exciting highlight of this meeting was provided by Professor Robert Ogilvie (MUSC Department of Cell Biology and Anatomy) when he introduced participants to a new digital technology that is revolutionizing histology and histopathology in the medical field. The Virtual Slide technology creates digital images of histological tissue sections by computer scanning actual slides in high definition and storing the images for retrieval and viewing. Virtual slides now allow any investigator with access to a computer and the web to view, search, annotate and comment on the same tissue sections in real time. Medical and veterinary slide libraries across the country are being converted into virtual slides to enhance biomedical education, research and diagnosis. The coral health and disease researchers at this workshop deem virtual slides as a significant way to increase capabilities in coral histology and a means for pathology consultations on coral disease cases on a global scale.

NOAA Technical Memorandum↗

USGS2002

Artificial intelligence based decision support for trumpeter swan management

The number of trumpeter swans (Cygnus buccinator) breeding in the Tri-State area where Montana, Idaho, and Wyoming come together has declined to just a few hundred pairs. However, these birds are part of the Rocky Mountain Population which additionally has over 3,500 birds breeding in Alberta, British Columbia, Northwest Territories, and Yukon Territory. To a large degree, these birds seem to have abandoned traditional migratory pathways in the flyway. Waterfowl managers have been interested in decision support tools that would help them explore simulated management scenarios in their quest towards reaching population recovery and the reestablishment of traditional migratory pathways. I have developed a decision support system to assist biologists with such management, especially related to wetland ecology. Decision support systems use a combination of models, analytical techniques, and information retrieval to help develop and evaluate appropriate alternatives. Swan management is a domain that is ecologically complex, and this complexity is compounded by spatial and temporal issues. As such, swan management is an inherently distributed problem. Therefore, the ecological context for modeling swan movements in response to management actions was built as a multiagent system of interacting intelligent agents that implements a queuing model representing swan migration. These agents accessed ecological knowledge about swans, their habitats, and flyway management principles from three independent expert systems. The agents were autonomous, had some sensory capability, and could respond to changing conditions. A key problem when developing ecological decision support systems is empirically determining that the recommendations provided are valid. Because Rocky Mountain trumpeter swans have been surveyed for a long period of time, I was able to compare simulated distributions provided by the system with actual field observations across 20 areas for the period 1988-2000. Applying the Matched Pairs Multivariate Permutation Test as a statistical tool was a new approach for comparing flyway distributions of waterfowl over time that seemed to work well. Based on this approach, the empirical evidence that I gathered led me to conclude that the base queuing model does accurately simulate swan distributions in the flyway. The system was insensitive to almost all model parameters tested. That remains perplexing, but might result from the base queuing model, itself, being particularly effective at representing the actual ecological diversity in the world of Rocky Mountain trumpeter swans, both spatial and temporally.

Idaho, Montana, Utah, Wyoming↗

USGS2015

Efforts to eradicate yellow crazy ants on Johnston Atoll: Results from Crazy Ant Strike Team IX, December 2014-June 2015

The ecologically destructive yellow crazy ant (YCA; Anoplolepis gracilipes ) was first detected on Johnston Atoll in January 2010. Within eight months, the U.S. Fish and Wildlife Service had mobilized its first crazy ant strike team (CAST), a group of biologists dedicated to testing and identifying insecticidal baits to be used to eradicate the ant on the atoll. During December 2014‒May 2015 CAST IX focused on testing hydrogel crystals saturated with sucrose solution (25%) carrying the insecticides thiamethoxam and dinotefuran against YCA. A series of experiments, including artificial nest box trials, and field-based palatability trials and eradication tests on small (500 m2 or 0.05 ha) and large plots (2500 m2 or 0.25 ha), were conducted to test concentrations of thiamethoxam ranging from 0.0005% to 0.01%, and dinotefuran at 0.05%. Additionally, the cat food-based matrix containing dinotefuran (0.05%), the standard bait used to suppress YCA on Johnston since 2011, and textured vegetable protein (TVP) carrying dinotefuran at 0.1% and 0.05% were included in large plot tests. Nest box trials were inconclusive due to a consistent loss of queen and worker ants in control boxes, so they were discontinued. Palatability trials suggested higher dosages of thiamethoxam (0.005 and 0.01%) were less attractive than lower dosages (0.0005 and 0.001%) and controls (sucrose only), but small and large plot experiments failed to identify a thiamethoxam concentration that was consistently effective at killing YCA. In contrast, hydrogel containing dinotefuran was consistently effective, killing >95% of YCA on small and large plots. As expected, the cat food bait effectively reduced YCA abundances, but was slightly less effective than hydrogel containing dinotefuran over time. Three successive, approximately weekly treatments of large plots with hydrogel bait, or other baits followed by hydrogel bait, suggest an increasing overall effectiveness, with no aversion of YCA to the bait. This finding is important in that it indicates that hydrogel bait can be applied at short time intervals, potentially resulting in relatively constant exposure of YCA to highly attractive, yet toxic, sucrose-based bait. TVP performed similar to hydrogel, reducing YCA abundance >92% at both concentrations tested. Finally, dosages of hydrogel containing dinotefuran at 6, 12 and 24 l/0.25 ha were all effective at reducing YCA on large plots. Overall, results from these experiments suggest that hydrogel containing dinotefuran (0.05%) is a promising tool for eradicating YCA on Johnston Atoll.

Hawaii↗

USGS1999

Herpetology in the federal government: a personal view

In late 1976, I received a phone call from an ichthyological colleague who asked if I would be willing to take a temporary position in the U.S. Fish and Wildlife Service's (FWS) Office of Endangered Species (OES) in Washington. They had a backlog of proposed and final rules that needed to be finished, and they thought that a 30-day stint by a temporary herpetologist would clear the slate. Thus began a 23-year odyssey through the sometimes bizarre, sometimes rewarding, sometimes discouraging, but always different federal government. Fortunately, I have been able to stay involved with herpetology, both as a science and in terms of conservation policy. In my career, I have worked both in an administrative and in a research capacity. Many individuals with an interest in herpetology enter the federal government as field biologists and drift into administration as they become older and removed from the dynamically changing nature of their science. I moved in the other direction.

Herpetologists' League Communications↗

USGS1965

Relative toxicities of similar formulations of pyrethrum and rotenone to fish and immature stoneflies

The insecticidal properties of rotenone and pyrethrum have been known for many years. Both toxicants have long histories of extensive use for control of a variety of insect pests. Rotenone has been also employed as a management tool by fishery biologists to rehabilitate fishing waters, and its toxicity to fish in a number of ecological situations is well established. Pyrethrum's toxicity to fish is less well known.

Pyrethrum Post↗

USGS2007

Analysis of the sea otter ( Enhydra lutris ) reproductive tract: A methods manual

Reproduction in the female sea otter, Enhydra lutris, was relatively unstudied until Sinha et al. (1966) examined 140 reproductive tracts collected 1955-62 and used their findings to describe sea otter reproductive anatomy and biology. Two years later Sinha and Conaway (1968) published a more detailed paper on the ovary of the sea otter. These descriptive papers have been used as the basis for all subsequent studies of sea otter reproductive tracts. During biological collections of sea otters in the 1960s and 70s a large number of female carcasses became available to wildlife biologists. Using Sinha’s research, Schneider (1973) analyzed 1,482 female reproductive tracts to determine the timing of reproduction, gestation period, age of sexual maturity, fetal sex ratio and growth rate of otters in the Aleutian Islands. A similar study was conducted by Bodkin et al. (1993) on a sample of 177 females collected after the 1989 Exxon Valdez oil spill. Recently (von Biela 2007) examined 134 reproductive tracts obtained from beachcast and harvested otters across the three Alaskan population stocks as part of a Master’s thesis. As with most life history data, comparisons among and within populations that differ in status relative to equilibrium densities provide useful data with which to test hypotheses about the cause and effects of changes in demographic rates such as reproductive rate. However, in order to make such comparisons, methods used in different periods must be comparable. The purpose of this manual is to explicitly describe how to collect and analyze sea otter reproductive tracts for the determination of reproductive rate, pregnancy rate, percentage of mature females, and timing of reproduction so that the data will be directly comparable to that collected in the past. The techniques presented in this manual have been used to study sea otter populations over the last 50 years, and maintaining such consistency is essential to comparisons in the future. This manual is based on the methods of previous researchers and draws heavily on the published and unpublished works of James Bodkin, Karl Kenyon, Calvin Lensink, Daniel Mulcahy, Karl Schneider, and Akhouri Sinha. Most invaluable to the production of this manual were the direct communications with Karl Schneider and Dan Mulcahy. In each instance, researchers have communicated with each other to attain comparable methods. Recognizing that researchers in the future may not have this luxury, this guide has been produced to preserve the technique. In addition to using this manual, researchers should consult with colleagues experienced in the analysis of mammalian reproductive tracts, preferably specific to sea otters. Individuals are encouraged to contact V. von Biela with any questions. Sea otter reproductive tracts have most commonly come from either intentional sampling through harvests (Sinah et al. 1966, Schneider 1975) or unintentional large scale mortalities (e.g. the 1989 Exxon Valdez oil spill) (Bodkin et al. 1993). Carcasses and reproductive tracts can also be obtained through the collection of fresh beach cast carcasses. Analysis of reproductive tracts should consider the source of carcasses as samples representing either the “living” or “dead” sea otter population, as they may differ in reproductive parameters. In most cases the reproductive tracts are fixed in formalin or frozen (minimum of –20˚C) immediately after collection; both methods are acceptable for later analysis of the tissue. Immediate fixation is preferred as it is a necessary step in analysis. Uteri and ovaries are then examined to determine the current and past reproductive history of each individual. This manual also includes an example datasheet (Appendix A) and glossary (Appendix B).

Technical Report↗

USGS1987

Standardization of stain used for diagnosing erythrocytic inclusion body syndrome (EIBS)

Erythrocytic inclusion body syndrome (EIBS), a viral erythrocytic necrosis (VEN)-like disease, has been observed in several areas in the Northwest. This virus disease is clinically diagnosed by microscopic examination of blood smears for intracytoplasmic erythrocytic inclusion bodies. Fish biologists involved in EIBS diagnostic work have been using several types of hematological stains. It became apparent that standardization of the staining procedure was needed. Comparative tests were conducted on blood smears and kidney imprints with the following commonly used blood stains: (1) Leishman-Giesma, (2) Pinacyanol chloride, (3) Powell 's Giemsa, (4) Harleco's Giemsa, (5) Diff Quik differential stain, (6) Wright's. Pinacyanol chloride stain was found to be the most consistent. The following staining procedure is recommended.

Fish Health Newsletter↗

USGS2005

Toxicity to amphibians of environmental extracts from natural waters in National Parks and Fish and Wildlife Refuges

Amphibian population declines are not limited to overly degraded habitats, but often occur in relatively pristine environments such as national parks or wildlife refuges, thus forcing biologists to examine less obvious causes for declines such as the presence of contaminants. The objective of our study was to extract naturally-occurring compounds from amphibian habitats (using semipermeable membrane devices) in three national parks or wildlife refuges (two sites within Sequoia Kings Canyon National Park, Big Bend National Park, and Kenai National Wildlife Refuge), and assess their toxicity to developing larvae using bioassays. Extracts did not cause mortality, so all effects observed were sublethal, influencing life history characteristics. In all three areas studied, amphibians reared in extracts from at least one of the two sites exhibited either a lengthened larval period or reduced mass at metamorphosis. Extracts from both the air and water at one site in Sequoia Kings Canyon National Park lengthened the larval period, which is in agreement with studies showing elevated levels of aerially transported contaminants at sites such as this within the park. Ultraviolet radiation, which is also suspected of having caused amphibian declines and was included as a factor in our study, did not act alone or alter the toxicity of the extracts.

Alytes↗

USGS2007

Current and potential ant impacts in the Pacific region

Worldwide, ants are a powerful ecological force, and they appear to be dominant components of animal communities of many tropical and temperate ecosystems in terms of biomass and numbers of individuals (Bluthgen et al. 2000). For example, ants comprise up to 94% of arthropod individuals in fogging samples taken from diverse lowland tropical rainforest canopies, and 86% of the biomass (Davidson et al. 2003). The majority of these ant species and individuals obtain carbohydrates either from extrafloral nectaries or from sap-feeding Hemiptera that pass carbohydrate-rich “honeydew” to attending ants while concentrating nitrogen (N) from N-poor plant sap (Davidson et al. 2003). Honeydew and nectar represent key resources for arboreal ant species, although most ant species are at least partly carnivorous or scavengers (Bluthgen et al. 2004). In contrast to most of the terrestrial world, the biotas of many Pacific islands evolved without ants. Whereas endemic ant species are found in New Zealand (ca. 10 spp.), Tonga (ca. 10 spp.), and Samoa (ca. 12 spp.), other islands of Polynesia and parts of Micronesia likely lack native ants (Wilson and Taylor 1967, Wetterer 2002, Wetterer and Vargo 2003). About 20 Indo-Australian and western Pacific ant species range to the east and north of Samoa, but it is unclear how many of these were transported there by humans at some time (Wilson and Taylor 1967). Most of the remainder of the ant species currently found on Pacific islands are widespread species that fall in the category of “tramp species,” dispersed by recent human commerce and generally closely tied to human activity and urban areas (Wilson and Taylor 1967, McGlynn 1999). In Pacific island situations, some of these tramp ant species are able to thrive beyond areas of human activity. Relatively few ant species have been successful invaders of native communities on continents, and these include most of the species that pose the greatest problems for Pacific islands. They generally have multiple queens per colony, are unicolonial (lacking internest aggression), quickly recruit to food items, thrive in a variety of habitats including disturbed areas, and can be highly aggressive to other ant species (McGlynn 1999). Hawaii’s arthropod fauna evolved in the absence of ants and has been observed by many biologists to be highly vulnerable to displacement by non-native ants. Pacific island biotas have also very likely suffered greatly from displacement by ants. However, in contrast to Hawaii, virtually nothing has been published on effects of non-native ants on native arthropod fauna elsewhere on Pacific islands, with the exception of the Galapagos archipelago, which may have at least four species of endemic ants (Lubin 1984, Nishida and Evenhuis 2000) and New Caledonia (Jourdan et al. 2001, Le Breton et al. 2005). In addition, many ant species in the Pacific have long been a nuisance for humans, and significant agricultural impacts have occurred from ants tending hemipteran insects of crop plants.

Proceedings of the Hawaiian Entomological Society↗

USGS2006

Does predator management enhance survival of reintroduced black-footed ferrets?

Predation on black-footed ferrets (Mustela nigripes) is a potential problem at reintroduction sites, causing up to 95 percent of the documented mortality of ferrets. Strategies to reduce mortality due to predation can focus on preconditioning ferrets prior to reintroduction and/or managing predators of ferrets. Biologists have tried three general strategies to control predators at reintroduction sites: (1) selective removal of individual predators, (2) nonselective removal of coyotes (Canis latrans), and (3) electric fences to exclude coyotes from release sites. We conducted a post hoc review of data from releases during 1994–2003 at 11 sites in South Dakota and Montana to address whether or not predator management has benefited reintroduced black-footed ferrets. Limited evidence indicates that (1) individual great horned owls (Bubo virginianus) can cause significant ferret mortality and that identifying and removing these individuals can be beneficial, (2) lethal control of coyotes may have inverse effects on ferret survival, and (3) electric fencing does not enhance short- or long-term survival of reintroduced ferrets. The data are confounded by a variety of factors, making conclusions tenuous. Well designed studies are needed to properly address the effectiveness of predator management for enhancing ferret survival.

Conference Paper↗