Nova J Silvy

• Professor at Texas A&M University

We obtained 1,899 hunter-harvested Montezuma quail (Cyrtonyx montezumae) wings from southeastern Arizona, USA, from the 2008–2009 hunting season. We determined age and sex based on plumage characteristics for 98.2% (1,864) of the original sample. One-way analysis of variance (ANOVA) of wing-chord length found differences (P < 0.001) based on sex,...

We surveyed the Naval Air Station in Key West, FL, to document state-listed herpetofauna in 2 different vegetation types using 3 motion-detecting infrared cameras centered within radiating drift fences. Cameras were activated on 21 June 2021 and retrieved on 30 November 2021. Of 225,153 photos taken, 1210 were of vertebrates (603 of herpetofauna, 5...

Florida Key deer (Odocoileus virginianus clavium) are an endangered subspecies of white‐tailed deer endemic to the Lower Florida Keys. The New World screwworm (Cochliomyia hominivorax) infestation in July 2016 and Hurricane Irma on 10 September 2017 both caused the Key deer population to decline. Our objective was to estimate current Key deer popul...

The landscape of fear (LOF) hypothesis is a unifying idea explaining the effects of predators on the space use of their prey. However, empirical evidence for this hypothesis is mixed. Recent work suggests that the LOF is dynamic, depending on the daily activity of predators, which allows prey to utilize risky places during predator down times. Whil...

Simple Summary New or revised techniques are being developed to improve management of expanding populations of invasive wild pigs. In southern Oklahoma, we set out to evaluate the success of various trap types: a conventional corral trap design, drop nets developed for capturing other wildlife, and recently developed suspended traps. Suspended trap...

North American porcupines (Erethizon dorsatum) have expanded their range into central Texas and are now frequent users of caves as den sites. What remains unknown is how caves affect their home range, and their local habitat preferences. This information is important for management decisions on Joint Base San Antonio – Camp Bullis where novel and a...

LIght Detection And Ranging (lidar) data have been widely used in the areas of ecological studies due to lidar’s ability to provide information on the vertical structure of vegetation in wildlife habitats. The overall objective of this project was to map the vegetation on No Name Key, Florida where endangered wildlife species reside using publicly...

The wild turkey is an iconic game bird with a long history of association with humans. Texas boasts the largest wild turkey population in the country. It is the only state where one can find native populations of three of the five subspecies of wild turkeys—the Eastern wild turkey (Meleagris gallopavo silvestris), the Rio Grande wild turkey (M. g....

The status of endangered Odocoileus virginianus clavium (Key Deer) on outer islands of Florida was unknown following several recent population declines. In response, we opportunistically monitored the western extent of the current range of Key Deer in Flordia using cameras and in-person observations to determine deer presence. We found evidence of...

The Montezuma quail (Cyrtonyx montezumae) is an arid‐land quail species found locally in the southwestern United States, and south into Mexico following the Sierra Madre Occidental mountain range to Oaxaca. The reproductive season (Jun to Sep) for Montezuma quail is late compared with other quail species, excluding scaled quail (Callipepla squamata...

Objective: The ruffed grouse, Bonasa umbellus, is broadly distributed across North America and displays considerable taxonomic diversity. Except for a genetic study of some western populations of ruffed grouse, nothing is known about genetic variation in other regions of Canada and the United States. Our objective is to examine patterns of mitocho...

With the exception of one species, the family Cracidae comprises forest and brushland bird species (ie, chachalacas, curassows, and guans) endemic to the Neotropics of Mexico and Central and South America. Mexico is the northernmost distributional range for many of these species groups, except for the plain chachalaca (Ortalis vetula), which extend...

The wild pig (Sus scrofa), an exotic and invasive species, has caused great concern at a global scale, particularly within agricultural landscapes. The objective of this study was to determine whether intensive trapping and wild pig removal resulted in a concomitant decrease in damage to rangelands. Removal of 356 wild pigs over 2 years showed an i...

Knowledge of meso-mammal cave use is essential for natural resource managers, particularly in the management of endangered cave invertebrates. Scat left by meso-mammals represents significant nutrient inputs into the oligotrophic cave environment which can disrupt the invertebrate species composition and ecology. Since little is known about what co...

This report provides U.S. Fish and Wildlife Service with the final overall report for the contract Screwworm Assessment and Monitoring for Florida Key Deer – Phase II. This report synthesizes all data through 31 August. Successful resolution of the screwworm incident reduced the need for Key deer data collection (i.e., less radiotelemetry and fewer...

Historical assumptions about Montezuma quail movements and home ranges at the population level are limited due to the lack of markrecapture studies on this species from which solid conclusions can be derived. Such information is crucial for estimating population sizes, densities, and rate of emigration and immigration throughout the landscape. Our...

Many facets of Montezuma quail (Cyrtonyx montezumae mearnsi) population dynamics, such as survival and causes of mortality, are unknown because of limited or lack of mark–recapture studies on wild populations of this species. Much of what is known about this species comes from casual observations in the field or from dog-assisted flush-count survey...

The red foxes (Vulpes vulpes) indigenous to the mountains of the western United States are high-elevation specialists that could face range reduction due to climatic warming, as well as potential encroachment, loss of adaptive alleles, and displacement by introduced nonnative red foxes. We investigated the genetic integrity of the native Rocky Moun...

Kit fox (Vulpes macrotis) life history and ecology has been extensively studied in the Great Basin and California's Central Valley, with fewer studies in hot desert regions resulting in regional knowledge gaps. To augment our understanding of kit fox life history and ecology, we conducted a 2-year radio-telemetry study of the desert kit fox (V. m....

Wild pigs ( Sus scrofa ) are causing increasing ecologic and economic damage at a global scale. Because wild pigs can carry ≥65 diseases that affect livestock, their widespread expansion threatens native wildlife and livestock. We screened wild pigs from south-central Oklahoma, US for antibodies against Brucella abortus , pseudorabies virus (PRV),...

The desert kit fox occupies an estimated 101,800 km 2 in California. Four previous studies have been conducted on this species with none reported seasonal or annual survival rates. We captured and fitted mortality-sensitive radio collars to 56 desert kit foxes between October 2012 and August 2014 to estimate seasonal and annual survival rates. Pred...

A dramatic decline in the abundance of the scaled quail (Callipepla squamata) has been observed across most of its geographic range. In order to evaluate the influence of land cover patterns and their changes on scaled quail abundance, we examined landscape patterns and their changes from the 1970s to the1990s in two large ecoregions with contrasti...

Context Free-ranging mammals contribute to faecal pollution in United States water bodies. However, research into wildlife impact on water quality is dependent upon unreliable data (e.g. data uncertainty, unknown importance of parameters). Aims Our goal was to determine the potential impacts of common free-ranging mammal species and their manageme...

Nesting locations selected by wild turkeys (Meleagris gallopavo) have been widely studied, with vegetation conditions at nest sites regularly identified as important for nest site selection and success. However, nest site selection likely is also influenced by landscape characteristics. Therefore, we evaluated selection of nest sites by Rio Grande wi...

Aim The geographical expansion of white‐winged doves ( Zenaida asiatica ) in North America has attracted the attention of biologists and sportsmen because of their recreational and aesthetic value; however, data on factors driving the spatial spread of this species are lacking. We examined spatial and temporal patterns of range expansion for white‐...

Global increases in agricultural production have significant implications for biodiversity and ecosystem processes. In southern Africa, sugarcane production has converted native vegetation into agricultural monocultures. We examined functional group abundance along a conservation-agriculture gradient in the Lowveld of Swaziland. We captured small m...

Extensive research has been devoted to quantifying the habitat needs and selection of many wildlife species. However, how habitat selection affects the long-term demographic performance of a species largely has been ignored. We used northern bobwhite (Colinus virginianus) and brush canopy coverage—an important habitat component for quail—to evaluat...

Across the planet, high-intensity farming has transformed native vegetation into monocultures, decreasing biodiversity on a landscape scale. Yet landscape-scale changes to biodiversity and community structure often emerge from processes operating at local scales. One common process that can explain changes in biodiversity and community structure is...

Monk parakeets (Myiopsitta monachus) are native to South America and were exported as popular caged birds during the legal pet bird trade. Due to accidental and intentional releases, monk parakeets established naturalized, self-sustaining populations in the United States (US). This species is the only member of the parrot family (Psittacidae) that...

Rio Grande wild turkey (Meleagris gallopavo intermedia) nests suffer high predation rates exceeding 65%, which may limit recruitment. We evaluated post-nesting movements of reproductively active female Rio Grande wild turkeys. We monitored 194 nesting attempts between 2005 and 2010 and documented 17% and 32% overall apparent nest success for the Ed...

Context The role of wildlife in faecal pollution of water bodies (deposition of Escherichia coli (E. coli)) is not well understood. Current water-quality and land-use planning research largely relies on unreliable wildlife data (e.g. poor sourcing of abundance estimates, population density estimates applied to multiple fundamentally different areas...

We evaluated squeeze cages and water-soluble inks and dyes as methods for handling and marking of meso-mammals in a short-term capture-recapture study. Study animals exhibited no adverse physiological impacts from capture or marking techniques. We also observed no negative impacts on trap success for the duration of the study. We found these method...

Influential factors associated with population dynamics of mountain lions Puma concolor include exploitation rates, prey availability, habitat structure and social structure. Throughout most of North America, mountain lion harvest is regulated by state or provincial quotas or is protected by federal laws. In Texas, however, they are not classified...

A 1,011.7-ha wildfire occurred in southeast Arizona in May 2009 and provided an opportunity to evaluate pre-and post-fire abundance of and habitat use by Montezuma quail (Cyrtonyx montezumae) through use of flush surveys and radiotelemetry. We evaluated movements of radio-marked quail from 2 months prior to the burn to 12 months post-burn. We obser...

Inclement weather such as droughts or hard freezes are known to negatively impact quail species and population viability models exist which have evaluated northern bobwhite (Colinus virginianus) response to summer and winter catastrophes. Previous research suggests inclement weather may be an important factor that contributes to mortality of Montez...

Survey and trapping methods for Montezuma quail (Cyrtonyx montezumae) require means not traditionally used for other quail species (e.g., northern bobwhite, Colinus virginianus). Trapping Montezuma quail is most effective using pointing dogs at night when coveys can be located and captured by net during roosting. However, reduced visibility at nigh...

Degradation of coastal systems has led to increased impacts from hurricanes and storm surges and is of concern for coastal endemics species. Understanding the influence of disturbance on coastal populations like the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) is important to understanding long-term dynamics and for recovery pl...

We examined retention of butt-end aluminum leg bands on Rio Grande wild turkeys (Meleagris gallopavo intermedia) captured in Texas and Kansas, USA, 2000–2009. We examined 187 recaptured or harvested radiotagged wild turkeys to determine band retention and modeled band retention with Program MARK. We did not detect differences in band retention amon...

Deer–vehicle collisions (DVCs) are the primary source of mortality for the endangered Florida Key deer (Odocoileus virginianus clavium). Of these collisions, >50% occur on United States Highway 1 (US 1), the primary roadway connecting the islands in the Florida Keys, USA. The DVCs on the 5.6-km section of US 1 on Big Pine Key are responsible for ap...

Road-based distance sampling is a common technique used to estimate the density of many wildlife species but potential biases exist unless the target population is randomly distributed around roads. Our objective was to determine if and when Rio Grande wild turkeys (Meleagris gallopavo intermedia; RGWT) were randomly distributed around roads to ide...

Models are important tools that can help managers and researchers understand the population dynamics of a species and how different habitat or population management scenarios impact that species. We used radio-telemetry data from northern bobwhites (Colinus virginianus) in southern Texas from 2000 to 2005 to develop a stochastic simulation model fo...

Severe low frequency natural disturbances along stream networks can substantially alter urban and rural landscapes and impact habitat and population dynamics of wildlife species. In 1978, severe flooding along the North Prong of the Medina River significantly altered the habitat for the Rio Grande wild turkey and may have contributed to the decreas...

We conducted the most intensive estimate of the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) metapopulation to date using pellet surveys and capture–recapture methodology. We livetrapped 83 rabbits, evaluated 5 closed population models, and selected the model that best represented the data. We considered the variation in behavi...

Nest predation is thought to be one of the major factors limiting northern bobwhite (Colinus virginianus) populations. We examined the relative impact of altering nest-predation rate, nesting habitat, and weather (i.e., temp and precipitation) on northern bobwhite population dynamics in a hypothetical 15,000-ha subtropical-rangeland ecosystem in so...

Rio Grande wild turkey (Meleagris gallopavo intermedia) populations in Texas appear to be declining, and poor nest success could be contributing to the decline. Techniques to monitor nest success and predator impacts are necessary to make sound conservation decisions. We evaluated nest predator community structure and researcher-induced impacts on...

Declines in Lesser Prairie-Chicken (Tympanuchus pallidicinctus) populations have been attributed to loss or fragmentation of habi-tat and conversion of native prairie to agricultural cropland, and have been exacerbated by improper grazing practices and drought. Loss of adequate vegetation for nesting and brooding of Lesser Prairie-Chickens have acc...

Rio Grande wild turkey (Meleagris gallopavo intermedia) abundance has declined in portions of the Edwards Plateau of Texas since the late 1970s. Because reproductive performance influences population dynamics, our objectives were to evaluate how hen reproductive activities varied between areas of stable and declining populations. We evaluated produ...

ABSTRACT  In the natural resource and wildlife profession, we face difficulties in the production, diffusion, and transfer of rigorously tested science, especially when facing entrenched management paradigms. We present 3 case studies to illustrate the challenges in changing entrenched management paradigms for endangered species. Here we examine sp...

ABSTRACT  Approximately 26% of annual mortality for the endangered Florida Key deer (Odocoileus virginianus clavium) occurs as deer-vehicle collisions (DVCs) on the 5.6-km section of United States Highway 1 (US 1) on Big Pine Key (BPK), but extensive urban development adjacent to sections of US 1 complicates efforts to reduce DVCs. Our objective wa...

The endangered Florida Key deer (Odocoileus virginianus clavium) is endemic to the Lower Florida Keys. In recent years, habitat fragmentation and restricted dispersal have resulted in small, isolated herds on some islands. Recovery biologists proposed translocations to increase the island herds that had declined or remained low; however, efficacy o...

Abstract A number of studies on mammalian species that have adapted to urban areas suggest survival may be higher for urban populations than rural populations. We examined differences in fatalities between an urban and rural population of fox squirrels (Sciurus niger). We radiocollared (n = 50 rural, n = 78 urban) fox squirrels during approximately...

High white-tailed deer (Odocoileus virginianus) densities in urban areas typically result in human-wildlife conflicts (e.g., deer—vehicle collisions, transmission of disease to humans, and vegetation damage). Controlling deer densities via fertility control generally is more acceptable than lethal removal in many urban areas and can reduce conflict...

A previous analysis of the content of articles published in The Wildlife Society (TWS) journals from 1937 to 1989 concluded that TWS should strive to publish more articles on nongame and endangered species, ecosystems, habitat fragmentation, and human dimensions. We revisited this analysis and included the years 1990–2007 to determine whether, and...

Latinos in the United States are an increasing segment of the population and are becoming important stakeholders in the management of natural resources. Although Latinos have been included in attitudinal research on environmental concerns, few studies have focused exclusively on Latino attitudes toward natural resources and the environment. We surv...

ABSTRACT  Agricultural intensification is a key factor in the decline of many avian populations throughout the world, yet the exact mechanisms that contribute to these declines are relatively unresolved, especially for seed-eating species. We tested the hypothesis that forage quality, particularly protein content, limits productivity in birds consu...

The Lower Keys marsh rabbit (LKMR, Sylvilagus palustris hefneri), a marsh rabbit subspecies endemic to the Lower Keys, Florida was protected in 1990, however, populations continue to decline despite recovery efforts. We hypothesized on-going habitat loss and fragmentation due to succession and hardwood encroachment has lead to increased edge, reduc...

The southeastern portion of the Edwards Plateau of Texas, historically a stronghold of Rio Grande wild turkeys Meleagris gallopavo intermedia, has seen the numbers of turkeys declining since the 1970s. Because hen survival is a key parameter affecting turkey population dynamics, we monitored radio-tagged Rio Grande wild turkey hens on the Edwards P...

With decreased illegal hunting and better habitat conservation, the Florida Key deer (Odocoileus virginianus clavium) population grew from an estimated 25–50 animals in the late 1940s to approximately 200 animals on Big Pine and No Name keys, Florida, USA, by 1971, the last official survey. U.S. Fish and Wildlife Service (USFWS) trend data indicate...

We examined abiotic and biotic variables potentially associated with Northern Bobwhite (Colinus virginianus) nest-site selection and nest success in southern Texas, USA during 2002–2005. These data were used to characterize bobwhite nest-site selection, and to develop and evaluate models of daily nest survival in Program MARK. Nest sites (n = 123)...

The introduction of pen-reared Attwater's prairie-chickens (APC, Tympanuchus cupido attwateri) into the wild to supplement existing populations has met with marginal success. Flight characteristics, predator avoidance behavior, and rearing methods may contribute to post-release mortality of pen-reared birds. We compared flight characteristics and p...

We investigated the effects of urban noise on auditory surveys of White-winged Doves (Zenaida asiatica) in two major cities in Texas. We conducted auditory point counts throughout the morning in San Antonio (n = 6) and Austin (n = 10) during week days (when traffic noise is higher) and weekends. We categorized survey points as near or far from road...

The endangered Florida Key deer (Odocoileus virginianus clavium) is endemic to the Florida Keys, Florida, USA, with Big Pine Key (BPK) supporting most (approx 60%) of the population. Habitat loss and fragmentation have altered the amount of available habitat, creating areas of varying suitability; north BPK (NBPK) is believed to contain more optima...

Wildlife managers require reliable, cost-effective, and accurate methods for conducting population surveys in making wildlife management decisions. Traditional methods such as spotlight counts, drive counts, strip counts (aerial, thermal, infrared) and mark–recapture techniques can be expensive, labor-intensive, or limited to habitats with high vis...

Reoccurring infection of reticuloendotheliosis virus (REV), an avian oncogenic retrovirus, has been a major obstacle in attempts to breed and release an endangered grouse, the Attwater's prairie chicken (Tympanicus cupido attwateri). REV infection of these birds in breeding facilities was found to result in significant decreases in the CD4(+) and i...

Lesser prairie-chickens Tympanuchus pallidicinctus have declined throughout their range because of loss or fragmentation of habitat from conversion of native prairie to agricultural cropland, exacerbated by overgrazing and drought. We used data from radio-marked lesser prairie-chickens to determine whether differences in survival existed between po...

Considerable controversy has often surrounded proposals to confer official status (i.e., list) species under the authority of the Endangered Species Act (ESA) of 1973 as amended or its precursors. Recent proposals to list the lesser prairie-chicken (Tympanuchus pallidicinctus), the western sage grouse (Centrocercus urophasianus phaios), and the Gun...

Increasing white-tailed deer (Odocoileus virginianus) numbers in urban environments is a management problem for both natural resource agencies and urban residents because of economic (e.g., deer-vehicle collisions) and ecological (e.g., ornamental and native vegetation damage) issues associated with deer “overabundance.” Reducing deer numbers using...

Obtaining reliable survival estimates is important in the management of wildlife populations, particularly for the construction of computer simulation models. Many methods for estimating survival (e.g., radiotelemetry) are cost-prohibitive or time consuming. Life tables can provide survival estimates using data routinely collected by some managemen...

The binturong Arctictis binturong and yellow-throated marten Martes flavigula are widely distributed through much of Southeast Asia, yet their natural history remains poorly understood. We radio collared and tracked five male binturongs, and five yellow-throated martens (four males and one female) for 4–23 months in Phu Khieo Wildlife Sanctuary, Th...

Over the last two decades, declines in trap success, stick-nest density and population density estimates have fueled concerns that the federally endangered Key Largo woodrat (KLWR, Neotoma floridana smalli) population is declining. Information on the current population status and habitat selection of KLWR is needed in the recovery of this populatio...

We followed the fate of nests of Rio Grande Wild Turkeys (Meleagris gallopavo interme-dia) on the Edwards Plateau of Texas during 2006 and 2007 using motion-activated digital cameras on a sub-set of nests to evaluate the frequency of nest predation and to identify nest predators. Predation was the pri-mary cause of loss for nests with cameras, acco...

The expansion of urban areas into native habitat can have profound effects on avian populations and communities, yet little is known regarding the effects of urban features on avian reproductive success. The objective of this study was to examine the reproduction of an urban-enhanced species, the mourning dove, to determine how tree and urban lands...

We used radiotelemetry to locate daytime forms of endangered Lower Keys marsh rabbits (LKMRs; Sylvilagus palustris hefneri) throughout their range so we could determine habitat characteristics of diurnal cover. We typically found forms (n = 1,298) of 36 rabbits in brackish wetlands in patches of saltmarsh or buttonwoods. In freshwater wetlands, for...

Remote-triggered cameras are an important tool in wildlife research and the increasing availability of digital camera technology can potentially provide researchers with additional options and benefits. We compared the performance and cost of a remote digital camera system (passive infrared) with 2 well-established remote film-based camera systems...

Surface-mined land reclamation creates grass and shrub lands that provide important wildlife habitat, particularly for disturbance-dependent birds. Declines in disturbance-dependent birds have been observed for 30 years, emphasizing the importance of proper reclamation strategies. Understanding the influence of spatial factors on nesting ecology of...