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USGS1984

Refuge management analyses: research needs for Muscatatuck National Wildlife Refuge

Muscatatuck National Wildlife Refuge, located in southeastern Indiana, was established by the Migratory Bird Conservation Commission in 1966. Land use planning for the Refuge formally began in 1971, and development of facilities designed in that planning effort is now nearing completion. As these facilities become operational, Refuge personnel will be manipulating water (both spatially and temporally) and other habitat components to achieve the joint Refuge goals of natural resource conservation and public use. This situation offers a unique opportunity to institute research and management studies designed to evaluate and enhance the effectiveness of the management regime in providing for the needs of migratory waterfowl and other wildlife resources.

Indiana↗

USGS1989

Effects of fire in the Northern Great Plains

This publication is a review of selected literature about prescribed burning in the Northern Great Plains (NGP) for management of wildlife. It also will be useful to other resource managers and researchers and to persons interested in the NGP. It is more 'descriptive' than 'interpretative.'The publication is a joint effort of the South Dakota State Cooperative Fish and Wildlife Research Unit (SDCFWRU), South Dakota State University, Brookings; the Northern Prairie Wildlife Research Center (NPWRC), Jamestown, N.D.; and the U.S. Fish and Wildlife Service (USFWS), Fergus Falls, Minn. Manuscript typing and library services were shared between SDCFWRU and NPWRC.This publication (EC 761) is the second of three SDSU Extension circulars on grassland fires. EC 760 is Prescribed burning guidelines in the Northern Great Plains; EC 762 is Annotated bibliography of fire literature relative to northern grasslands in South-Central Canada and North-Central United States and contains many more citations than presented in this publication. All three circulars may be obtained from either the Wildlife and Fisheries Sciences Department; SDSU Box 2206; ph (605) 688-6121; or from the Ag Communications Bulletin Room; SDSU Box 2231; ph (605) 688-5628; both in Brookings, S.D. 57007.

Report↗

USGS1993

The common wolf snake, Lycodon aulicus capucinus, a recent colonist of Christmas Island in the Indian Ocean

The discovery of the common wolf snake, Lycodon aulicus capucinus , on Christmas I . in the Indian Ocean suggests that individuals of the species have colonised the island recently. On the basis of biological information for this widespread colubrid snake and for the brown tree snake, Boiga irregularis, a well-documented pest species on Guam, the establishment of the common wolf snake would pose a severe threat to the native fauna and ecology of Christmas I. Immediate research is needed to document the spread of the snake, to evaluate its effects on other fauna, and to control or eradicate the species before it becomes firmly established.

Christmas Island↗

USGS2024

Wildlife stewardship on Tribal lands: Our place is in our soul By Serra J. Hoagland and Steven Albert (Eds.), Baltimore, Maryland: Johns Hopkins University Press. 2023. pp. 432. $59.95 (hardcover). ISBN 978-1-4214-4657-8

Despite thousands of years of land stewardship by Indigenous Peoples, Western ideology and science predominantly influences wildlife management in North America today. Indigenous science and Traditional Ecological Knowledge (TEK) extend beyond the scope of Western science and ecological understanding to include knowledge derived from generations of people living as part of ecosystems (Rinkevich 2008 ). Historically, Western science and TEK have operated separately, resulting in the exclusion of Indigenous Peoples and TEK in wildlife science and management, which has led to significant knowledge gaps in Western science. Today, many practitioners are seeking ways to study and manage wildlife in more inclusive ways that integrate multiple perspectives, including those from Indigenous communities, wildlife managers, researchers, and academics.

Journal of Wildlife Management↗

USGS1989

Premigrational movements and behavior of young mallards and wood ducks in north-central Minnesota

Movements and behavior of 89 young mallards (Anas platyrhynchos) and 48 young wood ducks (Aix sponsa) were monitored on a 932-km2 study area in north-central Minnesota in late summer and fall, 1972-74, with telemetry, visual observation, and aerial surveys. Initial flights of both species were confined to the natal (brood) marsh; first flights away from the natal marsh occurred in the third week after fledging in both species. First flights of young mallards and wood ducks away from their natal marshes were not significantly different between the sexes (mallard, mean = 4.95 km for females and 5.83 km for males; wood ducks, mean = 2.31 km for females and 2.64 km for males). However, flights away from the brood marshes by wood ducks were significantly shorter than for mallards.As young mallards and wood ducks grew, their daytime use of the natal marshes decreased in an irregular pattern as both species began daily flights between day- and night-use areas. Locally reared mallards made longer daily flights between use areas than did wood ducks, but wood ducks changed use areas with greater frequency before 1 October. Despite often extensive movements, most locally reared mallards and wood ducks remained in the vicinity of their brood marshes throughout fall until migration.Movement of young birds to new habitat was not the result of random searching and thus fortuitous discovery of nearby areas. Instead, birds seemed to learn of new habitat and develop movement patterns by associating with other birds; locally reared young always moved in the company of flocks of conspecifics that included adults and older immatures.Differences in movement patterns between the sexes of young birds and between young and adult birds cause them to be differentially distributed by age and sex on and near the breeding grounds. These differences are ultimately reflected in the distribution of the hunter harvest. We have interpreted generalizations about such phenomena, developed from analysis of continent-wide mallard banding data, using our data obtained from individually marked birds. We document (a) greater distances moved by early than by late-hatched young in the postbreeding period before migration, (b) differential movement of age and sex cohorts that explains greater hunting mortality of young than adults and of females than males near natal marshes, (c) differences in length and timing of postbreeding movements of adult male mallards and the postfledging movements of immature male mallards that help explain the northerly continental recovery distribution of young males, and (d) differential timing and rate of movement by birds through harvest areas (early departure of males and some return of females to natal marshes after the beginning of hunting) that explain differences in the timing of hunting season recoveries. Behavioral differences between the age and sex cohorts in the fall waterfowl population on and near their breeding grounds in north-central Minnesota can explain observed differences in survival and recovery rates of adult and young birds.The behaviors observed suggest to us that restrictive harvest regulations such as small-area closure may have little or no local benefits at the breeding grounds because premigratory assemblages of birds make extensive movements. In particular, protection of postbreeding adult females and locally reared young might only occur by closing large areas or scheduling extreme delays in the season opening, neither of which may be compatible with equitably apportioning waterfowl harvest at higher latitudes. Additional research on the local effects of restrictive regulations, and on age- and sex-specific differences in the timing, rate, and direction of fall movements of postbreeding waterfowl is needed.

Fish and Wildlife Research↗

USGS2011

Mitigating amphibian disease: strategies to maintain wild populations and control chytridiomycosis

Background Rescuing amphibian diversity is an achievable conservation challenge. Disease mitigation is one essential component of population management. Here we assess existing disease mitigation strategies, some in early experimental stages, which focus on the globally emerging chytrid fungus Batrachochytrium dendrobatidis . We discuss the precedent for each strategy in systems ranging from agriculture to human medicine, and the outlook for each strategy in terms of research needs and long-term potential. Results We find that the effects of exposure to Batrachochytrium dendrobatidis occur on a spectrum from transient commensal to lethal pathogen. Management priorities are divided between (1) halting pathogen spread and developing survival assurance colonies, and (2) prophylactic or remedial disease treatment. Epidemiological models of chytridiomycosis suggest that mitigation strategies can control disease without eliminating the pathogen. Ecological ethics guide wildlife disease research, but several ethical questions remain for managing disease in the field. Conclusions Because sustainable conservation of amphibians in nature is dependent on long-term population persistence and co-evolution with potentially lethal pathogens, we suggest that disease mitigation not focus exclusively on the elimination or containment of the pathogen, or on the captive breeding of amphibian hosts. Rather, successful disease mitigation must be context specific with epidemiologically informed strategies to manage already infected populations by decreasing pathogenicity and host susceptibility. We propose population level treatments based on three steps: first, identify mechanisms of disease suppression; second, parameterize epizootiological models of disease and population dynamics for testing under semi-natural conditions; and third, begin a process of adaptive management in field trials with natural populations.

Frontiers in Zoology↗

USGS2024

Reframing wildlife disease management problems with decision analysis

Contemporary wildlife disease management is complex because managers need to respond to a wide range of stakeholders, multiple uncertainties, and difficult trade-offs that characterize the interconnected challenges of today. Despite general acknowledgment of these complexities, managing wildlife disease tends to be framed as a scientific problem, in which the major challenge is lack of knowledge. The complex and multifactorial process of decision-making is collapsed into a scientific endeavor to reduce uncertainty. As a result, contemporary decision-making may be oversimplified, rely on simple heuristics, and fail to account for the broader legal, social, and economic context in which the decisions are made. Concurrently, scientific research on wildlife disease may be distant from this decision context, resulting in information that may not be directly relevant to the pertinent management questions. We propose reframing wildlife disease management challenges as decision problems and addressing them with decision analytical tools to divide the complex problems into more cognitively manageable elements. In particular, structured decision-making has the potential to improve the quality, rigor, and transparency of decisions about wildlife disease in a variety of systems. Examples of management of severe acute respiratory syndrome coronavirus 2, white-nose syndrome, avian influenza, and chytridiomycosis illustrate the most common impediments to decision-making, including competing objectives, risks, prediction uncertainty, and limited resources.

Conservation Biology↗

USGS2020

Introduction to life cycles, taxonomy, distribution and basic research techniques

Avian haemosporidian parasites are a closely related group of apicomplexan parasites with important similarities in their life cycles, development, physiology, and reproduction. Current phylogenies based on mitochondrial and nuclear genes reflect more traditional attempts to classify these organisms based on life history characteristics and morphology, but limited sampling from poorly characterized taxa such as the Garniidae from tropical and subtropical regions continues to limit our understanding of their phylogeny and evolution. Recent advances in molecular diagnostics and the ability to barcode these parasites using mitochondrial cytochrome b sequences have revolutionized the field, but traditional methodology based on microscopy of Giemsa-stained blood smears remains essential for diagnostics and understanding life history characteristics and biodiversity of these organisms. The relative strengths and weaknesses of current methods in wildlife haemosporidian research are discussed. We call for a combination of microscopic, PCR-based, and serological diagnostic methodologies for better estimates of true distribution and other aspects of biology of haemosporidians, particularly in studies on virulence, prevalence, and biodiversity.

Book chapter↗

USGS1988

Nonhunting mortality in sandhill cranes

Records of 170 sandhill cranes ( Grus canadensis ) necropsied at the National Wildlife Health Research Center, Wisconsin, from 1976 through 1985 were reviewed as representative samples to determine causes of nonhunting mortality in the mid-continent and Rocky Mountain populations of sandhill cranes. Avian cholera, avian botulism, and ingestion of mycotoxins were leading causes of nonhunting mortality. Hailstorms, lightning, lead poisoning, predation, avian tuberculosis, and collisions with power lines also killed cranes.

Journal of Wildlife Management↗

USGS1991

Wigeongrass ( Ruppia maritima ): a literature review

Wigeongrass (Ruppia maritima L.) is a submersed macrophyte of nearly cosmopolitan distribution and worldwide importance as a waterfowl food. Unfortunately, the plant no longer inhabits vast areas disturbed by human activities. Taxonomic status of the plant is uncertain, especially in North America. In mild climates, in habitats subject to environmental extremes, the plant behaves as an annual (vegetation perishes), or as a perennial in deeper, more stable habitats (some vegetative parts grow year round). Drupelets (seeds) provide a mechanism for wigeongrass to survive periods of drought and excessive water salinity. These sexual propagules can be washed ashore or carried by birds or fish for long distances.Wigeongrass mostly occurs in temporarily to permanently flooded mesohaline-hyperhaline estuarine wetlands, but it also occurs inland in fresh to hypersaline palustrine and lacustrine wetlands. Most populations inhabit warm, relatively unpolluted, and well lit waters <2.0 m deep where fetches and wave action are not great. The species is probably best adapted to stable water levels but can tolerate significant water level fluctuations, including periodic exposure in tidal areas. Robust growth occurs in areas of slow current. Wigeongrass is alone among the submersed North American angiosperms in tolerance to high salinity, but it is likely at a competitive disadvantage among specialist taxa in soft or acidic waters. The species grows in nearly all common bottom substrates, but growth is favored by aerobic and low H 2 S conditions. Turbidity frequently limits wigeongrass growth in waters overlying easily suspendible bottom substrates.Wigeongrass often occurs in monotypic stands, yet grows with many other submersed and emergent macrophytes. Dominance in certain wetlands sometimes alternates with dominance by other submersed macrophytes as salinities, seasonal temperature cycles, or other environmental factors change. The shading effect of metaphytic, planktonic, or epiphytic algae often reduces production.Wigeongrass and its detritus provide food and cover for a large invertebrate biota, although direct consumption of the living plants is minimal. Wigeongrass beds in coastal wetlands are heavily used by fish. The plant is recognized worldwide as an important food of migrant and wintering waterfowl, wading birds, and shorebirds. In subtropical climates, wintering waterfowl can quickly consume entire stands.Propagation and management of wigeongrass has occurred for nearly 60 years in the southern and eastern United States. During the seventies and eighties, sophisticated water level and salinity management techniques have been developed to encourage growth of the plant.Future research should concentrate on determining the means to reduce light-limiting turbidity in many wetland types; understanding the ways in which human activities on and near wetlands affect wigeongrass production; and developing reliable and predictable techniques to stimulate wigeongrass production by water level manipulations and other means in different environmental settings. Trophic interactions and the effects of biomanipulation of fish populations in managed wigeongrass habitat--now little understood--also require more study.

Fish and Wildlife Research↗

USGS2010

Estimating migratory game-bird productivity by integrating age ratio and banding data

Context: Reproduction is a critical component of fitness, and understanding factors that influence temporal and spatial dynamics in reproductive output is important for effective management and conservation. Although several indices of reproductive output for wide-ranging species, such as migratory birds, exist, there has been no theoretical justification for their estimators or associated measures of variance. Aims: The aims of our research were to develop statistical justification for an estimator of reproduction and associated variances on the basis of an existing national wing-collection survey and banding data, and to demonstrate the applicability of this estimator to a migratory game bird. Methods: We used a Bayesian hierarchical modelling approach to integrate wing-collection data, which provides information on population age ratios, and band-recovery data, which provides information on recovery probabilities of various age classes, for American woodcock ( Scolopax minor ) to estimate productivity and associated measures of variance. We present two models of relative vulnerability between age classes: one model assumed that adult recovery probabilities were higher, but that annual fluctuations were synchronous between the two age classes (i.e. an additive effect of age and year). The second model assumed that adults, on average, had higher recovery probabilities than did juveniles and that annual fluctuations were asynchronous through time (i.e. an interaction between age and year). Key results: Fitting our models within a hierarchical Bayesian framework efficiently incorporates the two data types into a single estimator and derives appropriate variances for the productivity estimator. Further, use of Bayesian methods enabled us to derive credible intervals that avoid the reliance on asymptotic assumptions. When applied to American woodcock data, the additive model resulted in biologically realistic and more precise age-ratio estimates each year and is adequate when the relative vulnerability to sampling only slightly varies or does not vary among components of a population (e.g. age, sex class) among years. Therefore, we recommend using woodcock indices from our analysis based on this model. Conclusions: We provide a flexible modelling framework for estimating productivity and associated variances that can incorporate ecological covariates to explore various factors that could drive annual dynamics in productivity. Applying our model to the American woodcock data indicated that assumptions about the variability in relative recovery probabilities could greatly influence the precision of our productivity estimator. Therefore, researchers should carefully consider the assumption of temporally variable relative recovery probabilities (i.e. ratio of juvenile to adults' recovery probability) for different age classes when applying this estimator. Implications: Several national and international management strategies for migratory game birds in North America rely on measures of productivity from harvest survey parts collections, without a justification of the estimator or providing estimates of precision. We derive an estimator of productivity with realistic measures of uncertainty that can be directly incorporated into management plans or ecological studies across large spatial scales.

Wildlife Research↗

USGS1990

Chironomidae of the southeastern United States: a checklist of species and notes on biology, distribution, and habitat

We provide a current listing of the species of midges (Diptera:Chironomidae) in the southeastern United States (Alabama, Florida, Georgia, North Carolina, South Carolina, and Tennessee). This checklist should aid research on this group of insects, which have often proved useful in the assessment of water quality. We document each species' distribution and general habitat and provide the best taxonomic reference to facilitate the identification or description of species in that genus. Changes in nomenclature, unique ecological traits, bibliographic sources, or other items of information are summarized in a paragraph on each genus. Of the 10 sub-families currently recognized in the Chironomidae, 7 occur in the Southeast. The chironomid fauna of the six southeastern States now consist of 164 described genera and 479 described species. In addition we have listed 14 genera and 245 species that are tenatively noted as undescribed.

Fish and Wildlife Research↗

USGS2022

Optimizing trilateration estimates for tracking fine-scale movement of wildlife using automated radio telemetry networks

A major advancement in the use of radio telemetry has been the development of automated radio tracking systems (ARTS), which allow animal movements to be tracked continuously. A new ARTS approach is the use of a network of simple radio receivers (nodes) that collect radio signal strength (RSS) values from animal-borne radio transmitters. However, the use of RSS-based localization methods in wildlife tracking research is new, and analytical approaches critical for determining high-quality location data have lagged behind technological developments. We present an analytical approach to optimize RSS-based localization estimates for a node network designed to track fine-scale animal movements in a localized area. Specifically, we test the application of analytical filters (signal strength, distance among nodes) to data from real and simulated node networks that differ in the density and configuration of nodes. We evaluate how different filters and network configurations (density and regularity of node spacing) may influence the accuracy of RSS-based localization estimates. Overall, the use of signal strength and distance-based filters resulted in a 3- to 9-fold increase in median accuracy of location estimates over unfiltered estimates, with the most stringent filters providing location estimates with a median accuracy ranging from 28 to 73 m depending on the configuration and spacing of the node network. We found that distance filters performed significantly better than RSS filters for networks with evenly spaced nodes, but the advantage diminished when nodes were less uniformly spaced within a network. Our results not only provide analytical approaches to greatly increase the accuracy of RSS-based localization estimates, as well as the computer code to do so, but also provide guidance on how to best configure node networks to maximize the accuracy and capabilities of such systems for wildlife tracking studies.

Ecology and Evolution↗

USGS1978

Atlantic walrus (Odobenus rosmarus rosmarus): A literature survey and status report

It is generally agreed that the genus Odobenus includes only one species, O. rosmarus . At least two subspecies are widely recognized: O. r. rosmarus , the Atlantic walrus, and O. r. divergens , the Pacific walrus. A third nominal subspecies, O. r. laptevi , the Laptev walrus, is designated by some Soviet researchers; and the taxonomic status of the Kara Sea walrus is undetermined. The range and abundance of nearly all walrus stocks have been seriously reduced by intensive human exploitation. The Atlantic walrus, the principal subject of this study, remains plentiful in only three known areas of concentration: northern Hudson Bay and northern Foxe Basin in the eastern Canadian Arctic, and the Thule district of northwest Greenland. This animal is no longer the object of large-scale commercial hunting, but is still subject to heavy subsistence hunting by native groups in some areas. The status of the walrus population in Canada was investigated in the 1950's and is believed to have changed little since that time. There are probably no more than about 10,000 walruses in Canadian waters, virtually all of them in the eastern arctic. The biology, ecology, and exploitation of walruses in the Thule district were studied during the 1940's, and some information is available concerning recent catch levels and hunting practices. The Polar Eskimos of north Greenland continue to organize much of their cultural and economic life around the hunting of walruses, and the species remains abundant in their area, numbering at least a few thousand. The walrus stocks off west Greenland and in the Greenland, Barents, and Kara seas are the most critically depleted. No systematic field investigations of walruses east of Greenland have been made since the Kara Sea and Franz Josef Land populations were studied in the mid-1930's. Opportunistic sighting records and compilations of historical catch information indicate that the herds of many tens of thousands that once inhabited Svalbard, Bear Island, Franz Josef Land, Novaya Zemlya, and other parts of the Eurasian Arctic have been very nearly extirpated. Measures to curb the international trade in walrus ivory and skins may benefit the Atlantic subspecies in Canada and north Greenland. Enforcement of existing regulations pertaining to hunting by aborigines, and perhaps the imposition of further restrictions on such activities, are necessary if the subspecies is to approach full recovery. Field studies in the northeast Atlantic and off west Greenland would help determine the current status of walruses and provide a better understanding of the requirements for their recovery in these areas. The Laptev walrus seems to have been reduced by overexploitation, but available information, most of it translated from Russian, is inconclusive. This subspecies was thought to number around 4,000 to 5,000 in 1975, and Soviet scientists have remarked on the need for a reduction in hunting pressure and protection of its habitat.

Wildlife Research Report↗

USGS2024

Duck hunters and difficulty complying with harvest regulations

Due to the steady decline of duck hunter participation, several studies have investigated means to bolster the duck hunter population. Researchers and wildlife professionals have assumed that simpler regulations would attract new and unconfident hunters to participate in duck hunting. In light of this, we sought to identify what portion of the duck-hunting population had difficulty understanding species-specific bag limits or complying with species-specific bag limits in the field. We also sought to describe hunters who had difficulty complying with specific bag limits and how their difficulties were associated with elements related to demography, attitude, and behavior. We found most hunters had no difficulty understanding (82%) or complying with (74%) species specific bag limits, but flyway (χ 2 = 35.06, P < 0.01), number of ducks harvested (χ 2 = 9.76, P < 0.01), number of years hunted (χ 2 = 9.20, P < 0.01), and gender (χ 2 = 4.14, P < 0.05), were important to predicting hunter difficulty with compliance. Hunters who can overcome their difficulties understanding and complying with species-specific bag limits may be more likely to be integrated into the duck hunting culture, and more likely to continue duck hunting in the future. More species identification tools and fewer species-specific bag limits may be appropriate for the 18% of the duck hunter population who indicated that bag-specific regulations were difficult to understand and the 26% who indicated that it was difficult to comply with species-specific bag limits in the field. A closer look may be warranted for how the trade-offs associated with the combination of species-specific bag limits in combination with the variety of duck season zone and split options states employ, license/stamp requirements, area-specific regulations, and trespass laws may influence duck hunter experiences.

Wildlife Society Bulletin↗

USGS2010

Patterns of space and habitat use by northern bobwhites in south Florida, USA

The manner by which animals use space and select resources can have important management consequences. We studied patterns of habitat selection by northern bobwhites ( Colinus virginianus ) on Babcock-Webb Wildlife Management Area, Charlotte County, Florida and evaluated factors influencing the sizes of their home ranges. A total of 1,245 radio-tagged bobwhites were monitored for 19,467 radio days during 2002–2007. The mean ( ± 1 SE) annual home range size, estimated using the Kernel density method, was 88.43 ( ± 6.16) ha and did not differ between genders. Winter home ranges of bobwhites (69.27 ± 4.92 ha) were generally larger than summer home ranges (53.90 ± 4.93 ha). Annual and winter home ranges were smaller for bobwhites whose ranges contained food plots compared to those that did not; however, the presence of food plots did not influence summer home ranges. We used distance-based methods to investigate habitat selection by bobwhites at two scales: selection of home ranges within the study site (second-order selection) and selection of habitats within home ranges (third-order selection). Across both scales, bobwhites generally preferred food plots and dry prairie habitat and avoided wet prairies and roads. This pattern was generally consistent between genders and across years. Our data indicate that management practices aimed at increasing and maintaining a matrix of food plots and dry prairie habitat would provide the most favorable environment for bobwhites.

Florida↗

USGS2010

Factors influencing reproductive performance of northern bobwhite in South Florida

Reproductive success is a critical component of individual fitness, and also an important determinant of growth rates of populations characterized by early maturity and high fecundity. We used radiotelemetry data collected during 2003–2008 to estimate reproductive parameters in a declining northern bobwhite ( Colinus virginianus ) population in South Florida, and to test hypotheses regarding factors influencing these parameters. The overall clutch size was 12.10 ± 0.22, but females laid more eggs in their first clutch (12.43 ± 0.24) than in subsequent clutches (10.19 ± 0.53) within a nesting season. Daily nest survival was higher for first (0.966 ± 0.003) than subsequent nests (0.936 ± 0.011). Hatchability (proportion of laid eggs that hatched conditional upon nest survival to hatching) was 0.853 ± 0.008, but was higher for nests incubated by females (0.873 ± 0.009) than those incubated by males (0.798 ± 0.018). The proportion of individuals attempting a second nest was 0.112 ± 0.024 and 0.281 ± 0.040 when the first nest was successful and failed, respectively. Hatchability was lower when the nesting habitat was burned the previous winter. We found no evidence that food strip density (a management practice to provide supplemental food) influenced any of the reproductive parameters. Mean summer temperature affected hatchability, nest survival, and proportion of nests incubated by males. Overall, the reproductive output in our study population was lower than that reported for most other bobwhite populations, indicating that low reproductive performance may have contributed to bobwhite population declines in our study site. These results suggest that current management practices, particularly those related to habitat and harvest management, need careful evaluation.

Florida↗

USGS2011

Spatial and temporal interactions of sympatric mountain lions in Arizona

Spatial and temporal interactions among individual members of populations can have direct applications to habitat management of mountain lions ( Puma concolor ). Our objectives were to evaluate home range overlap and spatial/temporal use of overlap zones (OZ) of mountain lions in Arizona. We incorporated spatial data with genetic analyses to assess relatedness between mountain lions with overlapping home ranges. We recorded the space use patterns of 29 radio-collared mountain lions in Arizona from August 2005 to August 2008. We genotyped 28 mountain lions and estimated the degree of relatedness among individuals. For 26 pairs of temporally overlapping mountain lions, 18 overlapped spatially and temporally and eight had corresponding genetic information. Home range overlap ranged from 1.18% to 46.38% (x̄=2443, SE = 2.96). Male–male pairs were located within 1 km of each other on average, 0.04% of the time, whereas male–female pairs on average were 3.0%. Two male–male pairs exhibited symmetrical spatial avoidance and two symmetrical spatial attractions to the OZ. We observed simultaneous temporal attraction in three male–male pairs and four male–female pairs. Individuals from Tucson were slightly related to one another within the population ( n = 13, mean R = 0.0373 ± 0.0151) whereas lions from Payson ( n = 6, mean R = -0.0079 ± 0.0356) and Prescott ( n = 9, mean R = -0.0242 ± 0.0452) were not as related. Overall, males were less related to other males ( n = 20, mean R = -0.0495 ± 0.0161) than females were related to other females ( n = 8, mean R = 0.0015 ± 0.0839). Genetic distance was positively correlated with geographic distance ( r 2 = 0.22, P = 0.001). Spatial requirements and interactions influence social behavior and can play a role in determining population density.

Arizona↗