Patrick K. Devers

• PhD
• Researcher at U.S. Fish and Wildlife Service

American black ducks Anas rubripes (hereafter, black ducks) are an important game species in the eastern United States (U.S.) and Canada that declined between the 1950s and 1990s, which resulted in the implementation of restrictive hunting regulations in the United States and Canada. Black duck harvest is managed by the Black Duck International Ada...

Survey data on species in the nightjar family (Caprimulgidae) suggest declines in population abundance across their range. State and federal migratory bird managers identified the need to monitor the status of nightjars including common nighthawk (Chordeiles minor), chuck‐will's‐widow (Antrostomus carolinensis), and eastern whip‐poor‐will (A. vocif...

The number of waterfowl hunters in the United States has declined since the 1980s despite relatively abundant waterfowl populations and liberal hunting regulations. Programs focused on recruiting, retaining, and reactivating (R3) waterfowl hunters have become important to avoid further losses in traditional revenue for habitat management and protec...

Managing sustainable harvest of wildlife populations requires regular collection of demographic data and robust estimates of demographic parameters. Estimates can then be used to develop a harvest strategy to guide decision‐making. Mallards ( Anas platyrhynchos ) are an important species in the Atlantic Flyway for many users and they exhibited expo...

The COVID‐19 pandemic has disrupted field research programs, making conservation and management decision‐making more challenging. However, it may be possible to conduct population assessments using integrated models that combine community science data with existing data from structured surveys. We developed a space–time integrated model to characte...

The common raven (Corvus corax; raven) is a nest predator of species of conservation concern, such as the greater sage-grouse (Centrocercus urophasianus). Reducing raven abundance by take requires authorization under the Migratory Bird Treaty Act. To support U.S. Fish and Wildlife Service's take decisions (e.g., those that authorize killing a speci...

The management of North American waterfowl is predicated on long‐term, continental‐scale banding implemented prior to the hunting season (i.e., July–September) and subsequent reporting of bands recovered by hunters. However, single‐season banding and encounter operations have a number of characteristics that limit their application to estimating de...

Multiple species are often exposed to a common hunting season, but harvest and population objectives may not be fully achieved if harvest potential varies among species and/or species abundances are not correlated through time. Our goal was to develop an approach for setting a common hunting season that would recognize heterogeneity in species prod...

Recreationists utilizing wetland birds for hunting or birdwatching contribute significantly to local economies and conservation efforts. The waterfowl management community, through the 2012 North American Waterfowl Management Plan (NAWMP), has explicitly recognized the need to increase recruitment and retention of wetland bird recreationists to hel...

The 2012 revision of the North American Waterfowl Management Plan (NAWMP) explicitly recognized the need to increase recruitment and retention of waterfowl hunters, birdwatchers, and other conservationists to maintain support for wetland conservation. The incorporation of human dimensions objectives within the NAWMP has compelled waterfowl and wetl...

The U.S. Fish and Wildlife Service (USFWS) uses data from the North American Breeding Bird Survey (BBS) to assist in monitoring and management of some migratory birds. However, BBS analyses provide indices of population change rather than estimates of population size, precluding their use in developing abundance-based objectives and limiting applic...

Wildlife managers routinely seek to establish sustainable limits of sport harvest or other regulated forms of take while confronted with considerable uncertainty. A growing body of ecological research focuses on methods to describe and account for uncertainty in management decision-making and to prioritize research and monitoring investments to red...

Data and expert elicitation results for parameters used in the assessment. (XLSX)

Parameter estimates provided to the expert elicitation panel as background material. (DOCX)

Derivation of harvest rate (hMSY) and absolute harvest (HMSY). (DOCX)

R-code for simulations. (R)

Sensitivity of harvest difference to individual demographic parameters. (XLSX)

Density dependence regulates populations of many species across all taxonomic groups. Understanding density dependence is vital for predicting the effects of climate, habitat loss and/or management actions on wild populations. Migratory species likely experience seasonal changes in the relative influence of density dependence on population processe...

Understanding migratory connectivity for species of concern is of great importance if we are to implement management aimed at conserving them. New methods are improving our understanding of migration; however, banding (ringing) data is by far the most widely available and accessible movement data for researchers. Here, we use band recovery data for...

Banding Data from BDJV

Example BUGS code for analysis

American black ducks (Anas rubripes) are a harvested, international migratory waterfowl species in eastern North America. Despite an extended period of restrictive harvest regulations, the black duck population is still below the population goal identified in the North American Waterfowl Management Plan (NAWMP). It has been hypothesized that densit...

American black duck (Anas rubripes) populations declined by more than 50% between the 1950s and 1990s, and the species serves as a flagship for conserving salt marsh habitats along the Atlantic Coast. Black ducks have generally been well studied throughout the annual cycle, but surprisingly, we lack a synthetic, quantitative understanding of their...

In 2007, several important initiatives in the North American waterfowl management community called for an integrated approach to habitat and harvest management. The essence of the call for integration is that harvest and habitat management affect the same resources, yet exist as separate endeavours with very different regulatory contexts. A common...

The Sonoran pronghorn (Antilocapra americana sonoriensis) population in the United States declined to ≤33 animals in January 2003. Low population numbers and unstable recruitment are concerns for biologists managing this subspecies. We examined habitat use by pronghorn from 1999 to 2002 on a portion of the Barry M. Goldwater Range (BMGR) used for m...

The Appalachian Cooperative Grouse Research Project (ACGRP) was a multistate cooperative effort initiated in 1996 to investigate the apparent decline of ruffed grouse ( Bonasa umbellus ) and improve management throughout the central and southern Appalachian region (i.e., parts of Ohio, Pennsylvania, Rhode Island, Kentucky, West Virginia, Virginia,...

A goal of many resource selection studies is to identify those habitats selected by a species. However, favorability of a particular habitat feature is likely contingent on such factors as landscape composition, predation risk, and an individual's resource needs. Thus, habitat selection may vary depending on context, and identifying causes of varia...

El comportamiento de los venados buros del desierto (Odocoileus hemionus eremicus) cuando se asustan ha sido descrito, pero la distancia que se desplazan después de ser asustados no ha sido registrada Monitoreamos 8 venados (6 hembras, 2 machos) con radio-collares por 8 meses, acercándonos intencionalmente a pie hasta que los asustamos, esperamos 1...

From 1996 to 2001, researchers at 10 Appalachian study sites collected radiotracking data suffi cient to delineate 1,054 seasonal home ranges of Ruff ed Grouse (Bonasa umbellus; hereaft er "grouse"). Using information-theoretic model selection and paired comparison of home ranges from individual grouse, we evaluated indi-vidual, local, and landscap...

From 1996 to 2001, researchers at 10 Appalachian study sites collected radiotracking data sufficient to delineate 1,054 seasonal home ranges of Ruffed Grouse (Bonasa umbellus; hereafter “grouse”). Using information-theoretic model selection and paired comparison of home ranges from individual grouse, we evaluated individual, local, and landscape fa...

Acom production by oaks (Quercus spp.) is an important food resource for wildlife in many deciduous forests. Its role as a hard mast crop that can be either stored or used to build fat reserves for winter survival cannot be replaced by most other potential foods. Changes in forest management, introduced pests and pathogens, and increased deer popul...

Interspecific and intraspecific relationships have received much attention from ecologists and play an important role in the structure of wildlife communities, but researchers have rarely attempted to study interactions between phylogenetically unrelated organisms. We observed 6 interactions between badgers (Taxidea taxus) and red-tailed hawks (But...

It has been over 10 years since Kellert and Berry's (1987) pioneering study on the influence of gender on attitudes toward wildlife. Since data were gathered for that study, several sociopolitical movements have entered the American ecopolitical scene, including the Sagebrush Rebellion and the Wise Use Movement, providing impetus for a current asse...

Associations among causes of species endangerment in the United States reflect the integration of economic sectors, supporting the theory and evidence that economic growth proceeds at the competitive exclusion of nonhuman species in the aggregate.

Flight Control, containing anthraquinone, was field tested during 1997 in Colorado as a repellent to keep Canada geese (Branta canadensis) off turf. The product was sprayed at a rate of 1.9 kg per ha, using a boom sprayer towed by a golf cart. The reduction in goose numbers on the treatment plot was 95.1 % ten days after application. A decline of 6...