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At least 1,099 records · Page 61Linked to original sources
USGS2002

Waterbird use of bayland wetlands in the San Francisco Bay estuary: Movements of long-billed dowitchers during the winter

The San Francisco Bay estuary is a migration and wintering area for more than 1.5 million waterbirds on the west coast of North America. Because the estuary is located in a metropolitan area, development and diking of baylands (the region between the edge of the bay and the historical high tide line) have greatly altered the wetland landscape. Recently, conservation interests have promoted restoration of diked baylands to tidal salt marshes for the benefit of endangered native species. However, effects of tidal marsh conversion on the existing community of waterbirds in the baylands are largely unknown, especially in muted tidal marshes with restricted inflows and in artificial salt evaporation ponds where high waterbird densities are found. The first radio-marking study of the Long-billed Dowitcher ( Limnodromus scolopaceus ) was conducted in November-December 2000 to examine their use of baylands. We captured 32 birds by rocket netting in a muted tidal marsh on the North Bay and radio-marked them with 1.2 g transmitters affixed with glue. Individuals were tracked for an average of 20.3 d (±8.5 SD) and obtained 217 high tide and 195 low tide locations. Movements between tides (x̄ = 1.29±1.48 SD km) and home range sizes (x̄ = 17.7±16.0 SD km 2 ) were highly variable. Long-billed Dowitchers preferred open habitats such as muted tidal marshes during the high tide, but the majority (78.5%) also remained in these wetlands during low tide rather than feeding at nearby mud flats. Their avoidance of mud flats contrasted sharply with Western Sandpipers ( Calidris mauri ) but was similar to Black-necked Stilts ( Himantopus mexicanus ). Seven Long-billed Dowitchers flew 110 km inland to Central Valley wetlands in mid-December, a regional movement documented earlier for Dunlin ( Calidris alpina ) wintering on the coast. However, unlike Dunlin, their movements were not in response to rainfall but may have been in response to a low pressure front or possibly predictable flooding of fields in the Central Valley. Although the estuary is a major wintering area supporting large numbers of waterbirds, some birds such as Long-billed Dowitchers move inland to freshwater wetlands in the Central Valley.

Waterbirds↗
USGS2018

Mercury concentrations in multiple tissues of Kittlitz's murrelets (Brachyramphus brevirostris)

Mercury (Hg) is a non-essential, toxic metal that is distributed worldwide. Mercury biomagnifies in food webs and can threaten the health of top predators such as seabirds. The Kittlitz's murrelet (Brachyramphus brevirostris) is a seabird endemic to Alaska and the Russian Far East and is a species of conservation concern in the region. We determined Hg concentrations in eggshells, guano, blood, and feathers of Kittlitz's murrelets sampled from four locations in Alaska. Mercury concentrations in eggshells, guano, and blood were low compared to other seabird species. Mean Hg concentrations of breast feathers from Adak Island and Glacier Bay were significantly greater than those from Agattu Island or Icy Bay. Two Kittlitz's murrelets at Glacier Bay and one Kittlitz's murrelet at Adak Island had Hg concentrations above those associated with impaired reproduction in other bird species, and may merit further investigation as a potential threat to individuals and populations.

Alaska↗
USGS2021

Across borders: External factors and prior behaviour influence North Pacific albatross associations with fishing vessels

Understanding encounters between marine predators and fisheries across national borders and outside national jurisdictions offers new perspectives on unwanted interactions to inform ocean management and predator conservation. Although seabird–fisheries overlap has been documented at many scales, remote identification of vessel encounters has lagged because vessel movement data often are lacking. Here, we reveal albatrosses–fisheries associations throughout the North Pacific Ocean. We identified commercial fishing operations using Global Fishing Watch data and algorithms to detect fishing vessels. We compiled GPS tracks of adult black-footed Phoebastria nigripes and Laysan Phoebastria immutabilis albatrosses, and juvenile short-tailed albatrosses Phoebastria albatrus . We quantified albatrosses-vessel encounters based on the assumed distance that birds perceive a vessel (≤30 km), and associations when birds approached vessels (≤3 km). For each event we quantified bird behaviour, environmental conditions and vessel characteristics and then applied Boosted Regression Tree models to identify drivers and the duration of these associations. In regions of greater fishing effort short-tailed and Laysan albatrosses associated with fishing vessels more frequently. However, fishing method (e.g. longline, trawl) and flag nation did not influence association prevalence nor the duration short-tailed albatrosses attended fishing vessels. Laysan albatrosses were more likely to approach longer vessels. Black-footed albatrosses were the most likely to approach vessels (61.9%), but limited vessel encounters ( n = 21) prevented evaluation of meaningful explanatory models for this species of high bycatch concern. Temporal variables (time of day and month) and bird behavioural state helped explain when short-tailed albatrosses were in close proximity to a vessel, but environmental conditions were more important for explaining interaction duration. Laysan albatrosses were more likely to associate with vessels while searching and during the last 60% (by time) of their trips. Our results provide specific species–fisheries insight regarding contributing factors of high-risk associations that could lead to bycatch of albatrosses within national waters and on the high seas. Policy implications . Given the availability of Global Fishing Watch data, our analysis can be applied to other marine predators—if tracking data are available—to identify spatio-temporal patterns, vessel specific attributes and predator behaviours associated with fishing vessel associations, thus enabling predictive modelling and targeted mitigation measures.

Journal of Applied Ecology↗
USGS2009

Progress Report: Stratton Ecological Research Site - An Experimental Approach to Assess Effects of Various Grazing Treatments on Vegetation and Wildlife Communities Across Managed Burns and Habitat Controls

Understanding how management practices affect wildlife is fundamental to wise decisions for conservation of public lands. Prescribed fire and grazing timing are two management tools frequently used within publicly owned sagebrush ecosystems. We conducted a variety of surveys in order to assess the impacts of grazing timing strategies (early summer before peak green-up, mid-summer at peak green-up, and late summer after peak green-up) in conjunction with prescribed fire on avian and small mammal populations in a high-elevation sagebrush ecosystem. Avian surveys resulted in a large detection sample size for three bird species: Brewer's sparrow (Spizella breweri), horned lark (Eremophila alpestris), and vesper sparrow (Pooecetes gramineus). Brewer's sparrows had the lowest number of detections within the mid-summer grazing treatment compared to early and late summer grazing treatments, while horned larks and vesper sparrows had higher detection frequencies within the late summer grazing treatment. Summer and fall sage-grouse (Centrocercus urophasianus) pellet counts revealed that the greatest over-winter and over-summer use by sage-grouse occurred within the early summer grazing treatment with minimal use of burn treatment areas across all grazing treatments. Deer-mice (Peromyscus maniculatus) represented approximately 90 percent of small mammals captured and were most prevalent within the mid-summer grazing treatment. Sagebrush cover was greatest within the mid-summer grazing treatment. We monitored 50 and 103 nests in 2007 and 2008, respectively. The apparent success rate for shrub-obligate nesting species was 58 percent in 2007 and 63 percent in 2008. This research will support management of sagebrush ecosystems by providing public land managers with direct comparisons of wildlife response to management regimes.

Open-File Report↗
USGS2006

The distribution and conservation status of the Gull-billed Tern (Gelochelidon nilotica) in North America

The Gull-billed Tern (Gelochelidon nilotica) has until recently received little conservation and management attention within North America despite a relatively low overall population size and significant declines in parts of the breeding range. This lack of attention may stem in part from the wide distribution of the species, encompassing parts of six continents, and from its tendency to nest in relatively small, scattered and often ephemeral colonies. Populations of North American subspecies are alarmingly small. The current population of the eastern subspecies aranea in the U.S. is unlikely to exceed 3,600 pairs, with over 60% of these birds occurring in Texas. The Texas population has remained generally stable, but declines of populations in Maryland (where probably extirpated), Virginia, North Carolina, Florida, and possibly Georgia give cause for concern for this subspecies. For the western subspecies vanrossemi, as few as 250 pairs nest at only two locations in the U.S., both in California. When populations in western Mexico are considered, the entire vanrossemi population numbers only 600-800 pairs. Currently the Gull-billed Tern is listed as ?endangered? or ?threatened? in four states, and is considered to be of management concern in five others. The breeding range of the species has contracted and shifted slightly from its known historic range in the middle Atlantic states, but otherwise occupies its historic range in the United States and has expanded slightly to coastal southern California. Some range contraction in Mexico (e.g., in Sonora) may have occurred. In eastern Mexico, historical information is almost non-existent and knowledge of current distribution and abundance is incomplete. Main threats to populations in North America include loss of natural nesting islands through beach erosion or perturbations to estuarine functions, development or modification of upland habitats near breeding areas that may be important for foraging, and disturbances to colonies by humans and feral or human-subsidized predators. This species often nests on man-made substrates suggesting it could be responsive to management of breeding sites. Key research needs include more frequent and refined population monitoring, a better understanding of demographics, metapopulation dynamics and factors limiting populations as well as refinement of subspecies? breeding distributions and wintering ranges.

Waterbirds↗
USGS2022

MTAB 101, September 2022

This Memo to All Banders (MTAB 101) was released in September 2022. Subjects in this this memo are 1. The Chief’s Chirp; 2. Alerts – Highly Pathogenic Avian Influenza; 3. Staff updates – staff spotlight: BBL’s new contractor database manager; 4. News – Gamebirds Release, 1-Year Anniversary of Banders Without Borders, Latino Conservation Week, and Bander Portal Update Release; 5. A note from the permitting shelves; 6. A note from the supply room; 7. Data management – including important information regarding Bandit,, How to sign up for a Bander Portal account, why you should sign up for a bander portal account, and cleaning up your locations; 8. Banding and encounter highlights; 9. Auxiliary marker corner; 10. Message to the Flyways; 11. Message regarding the Banding Associations; 12. Moments in history; 13. Recent Publications; 14. Upcoming events; 15. Message from Canada’s Bird Banding Office; and 16. Request for information.

Memo to All Banders (MTAB)↗
USGS2016

Ecology and conservation of Lesser Prairie-Chickens in sand shinnery oak prairies

Sand shinnery oak (Quercus havardii) prairies are unique ecosystems endemic to sandy soils of eastern New Mexico, northwestern Texas, and western Oklahoma; the historic and current distribution of the Lesser Prairie-Chicken (Tympanuchus pallidicinctus) overlaps these prairie systems. Lesser Prairie-Chicken populations in sand shinnery oak prairies of the Southern Great Plains have declined substantially since the late 1980s, most likely due to conversion of nesting and brood-rearing habitat to row-crop agriculture and extended periods of drought. In addition to threats universal throughout the species distribution, this population is susceptible to a changing climate in an area that is already representative of an extreme environment for ground-nesting birds. Recent studies of Lesser Prairie-Chicken ecology in sand shinnery oak prairies have expanded our knowledge on the ecology and management of the species, but a thorough review of the historic and current literature is lacking. In addition, current management guidelines exist for Lesser Prairie-Chickens in mixed grass and sand sagebrush prairies, but there are no comprehensive management guidelines for the species in sand shinnery oak prairies. This information is paramount given unique aspects of the vegetation community, relative ecosystem drivers, and environmental variation in sand shinnery oak prairie and the species’ current status as a proposed threatened species under the United States Endangered Species Act. Herein, we provide a thorough synthesis of literature pertaining to the life history, habitat requirements, habitat management, and population management for Lesser Prairie-Chickens in sand shinnery oak prairie, provide management guidelines and recommendations for the species in this ecoregion, and highlight current and future research needs. Within our objectives, we place emphasis on two recently completed long-term investigations into Lesser Prairie-Chicken ecology in sand shinnery oak prairie - a 10-year vegetation data set collected in Roosevelt County, New Mexico, 2001–2011 and a 6-year Lesser Prairie-Chicken data set collected in Roosevelt County, New Mexico and Cochran, Hockley, Terry, and Yoakum counties, Texas, 2006–2012.

Book chapter↗
USGS2005

Current range of the eastern population of Painted Bunting (Passerina ciris). Part 1: Breeding

This paper presents the current breeding range of Painted Bunting (Passerina ciris) in a series of maps and a narrative, in particular that of the eastern population, which is restricted to the states of North Carolina, South Carolina, Georgia, and Florida. Some conservation measures are recommended to protect this population. In light of the extensive habitat loss in the Outer Coastal Plain of these states, which comprise the areas of the population's greatest density, it is imperative that a consortium of diverse interests work together to provide sufficient habitats for this colorful native songbird.

North American Birds↗
USGS2021

Integrating wildlife habitat models with state-and-transitions models to enhance the management of rangelands for multiple objectives

State-and-transition models (STMs) are tools used in rangeland management to describe linear and nonlinear vegetation dynamics as conceptual models. STMs can be improved by including additional ecosystem services, such as wildlife habitat, so that managers can predict how local populations might respond to state changes and to illustrate the tradeoffs in managing for different ecosystem services. Our objective was to incorporate songbird density into an STM developed for sagebrush rangelands in northwest Colorado to guide local management of sagebrush birds. The STM included two shrub-dominated community phases, a native grassland state, and a shrubland and grassland phase within an exotic-dominated state. We surveyed plots for songbirds, collected a suite of vegetation indicators at each plot, and quantified songbird habitat relationships with count-based regression models. We then used the estimated models to predict songbird density based on average vegetation conditions per state or community phase. Moderate or increasing shrub cover were important predictors for shrubland-associated species, and responses to understory components varied by species. In the STM, we predicted higher densities of shrubland-associated bird species in the shrub-dominated phases and higher densities of grassland-associated bird species in the state and phase lacking shrub cover. No single state or phase captured the highest density for all songbirds, illustrating the value of alternative states. Our results also demonstrate the utility of displaying traditional wildlife count models against the range of vegetation conditions associated with each state or phase to understand how wildlife density can vary within states and phases. Our approach can assist land managers to gauge the potential impacts of land-use decisions and natural vegetation variability on wildlife, especially for species of conservation concern.

Rangeland Ecology and Management↗
USGS1996

Geographic variation in migratory behavior of greater white-fronted geese ( Anser albifrons )

We studied the migration and winter distribution of adult Greater White-fronted Geese ( Anser albifrons frontalis ) radio-marked on the Yukon-Kuskokwim Delta (YKD) and Bristol Bay Lowlands (BBL) of Alaska from 1987 to 1992. The major autumn staging site for geese from both breeding areas was the Klamath Basin on the California/Oregon border. However, temporal use of this area differed markedly between populations. Geese from the BBL arrived at the Klamath Basin nearly 30 days before geese from the YKD and departed before most YKD geese had arrived. Ninety percent of BBL geese used the Klamath Basin in autumn, whereas 30% of YKD geese bypassed the Klamath Basin during autumn and instead flew directly to the Central Valley of California. Nearly all BBL geese migrated directly from the Klamath Basin to wintering areas in Mexico, bypassing the Central Valley. Ninety percent of the BBL geese wintered in Mexico, as opposed to <20% of the YKD geese. Wetlands of the Interior Highlands in the state of Chihuahua, particularly Laguna Babicora, were used by >90% of the radio-marked geese in Mexico. Marshes along the West Coast comprised the other important wintering habitat in Mexico. The Sacramento Valley of California was the predominant wintering area for YKD geese. BBL geese migrated north from Mexico into the San Joaquin Valley or Sacramento-San Joaquin Delta of California by the last week of January. Fifty-five percent of the BBL population used the Klamath Basin in spring, but many birds staged in eastern Oregon and western Idaho. In contrast, geese from the YKD staged almost exclusively in the Klamath Basin during spring before flying to staging areas in Alaska. Breeding allopatry and temporal partitioning on staging and wintering areas likely has contributed to the evolution of previously described phenotypic differences between these populations. These two populations, along with the Tule Greater White-fronted Goose (A. a. gambeli), may constitute a portion of a Rassenkreis, a group of subspecies connected by clines, each ecotype of which has independent conservation needs.

The Auk↗
USGS2003

Survival, dispersal, and home-range establishment of reintroduced captive-bred puaiohi, Myadestes palmeri

We monitored the survival, dispersal, and home-range establishment of captive-bred, reintroduced puaiohi Myadestes palmeri, a critically endangered thrush endemic to the island of Kauai. Fourteen captive-bred, juvenile birds were released from hacktowers in January-February 1999 and monitored for 8-10 weeks using radiotelemetry. All 14 birds (100%) survived to 56 days post-release. Two birds (14.3%) dispersed greater than 3 km from release site within 1 day of release. The remaining birds settled within 1 week and established either temporary home-ranges (mean area = 7.9??12.0 ha, range 0.4-31.9) or breeding home-ranges (mean area 1.2??0.34 ha, range 0.8-1.6). Temporary home ranges were abandonded by the beginning of the breeding season, and ultimately 6 of the 14 birds (43%) established breeding home ranges in the release area. The high survival rate bodes well for establishing additional populations through captive breeding and release; however, the 57% dispersal rate out of the target area means that several releases of birds may be necessary in order to repopulate a given drainage. Furthermore, observed dispersal and gene flow between the reintroduced and wild populations have important implications for management of the captive flock. Published by Elsevier Science Ltd.

Biological Conservation↗
USGS2003

Molecular status of the dusky Canada goose (Branta canadensis occidentalis): A genetic assessment of a translocation effort

Until recently, the dusky Canada goose ( Branta canadensis occidentalis ) was managedas one breeding population from the CopperRiver Delta (CRD), Alaska. Population numberson the CRD have declined precipitously over thelast three decades, due in part to changes inhabitat. In 1981, a pair of Canada geese,presumably B.c. occidentalis , wasreported nesting on Middleton Island (MID), inthe Gulf of Alaska. Numbers of Canada geese onthe island increased in the decade subsequentto a translocation of geese from CRD to MID,but it is unclear whether the increase isattributable to the translocation effort. Weused genetic data derived from three classes ofgenetic markers to clarify relationships ofCanada geese breeding in south-coastal Alaska. Geese were sampled from 5 populations: CRD,MID, Anchorage (ANC), Admiralty Island (ADM) insoutheastern Alaska, and Green Island (GRN) inPrince William Sound (PWS). Mitochondrial DNAanalyses demonstrate Canada geese from MID arenearly monomorphic for a unique haplotype fixedon GRN but not found in CRD or any otherbreeding population. Furthermore, nuclearmarkers consistently cluster MID with GRN tothe exclusion of CRD. We suggest the currentpopulation on MID is not derived from birdstranslocated from CRD, but rather that MID wasmost likely colonised by birds inhabiting otherisland habitats within the PWS. Furthermore,since geese from the CRD share mtDNA haplotypeswith geese from other breeding locales, theyapparently share recent common ancestry and/orgene flow with populations representing othersubspecies. Our genetic data raise questionsabout the validity of current management unitsof Canada geese.

Conservation Genetics↗
USGS2004

Monitoring programs need to take into account imperfect species detectability

Biodiversiry monitoring is important to identify biological units in need of conservation and to check the effectiveness of conservation actions. Programs generally monitor species richness and its changes (trend). Usually, no correction is made for imperfect species detectability. Instead, it is assumed that each species present has the same probability of being recorded and that there is no difference in this detectability across space and time, e.g. among observers and habitats. Consequently, species richness is determined by enumeration as the sum of species recorded. In Switzerland, the federal government has recently launched a comprehensive program that aims at detecting changes in biodiversity at all levels of biological integration. Birds are an important part of that program. Since 1999, 23 visits per breeding season are made to each of >250 1 km2 squares to map the territories of all detected breeding bird species. Here, we analyse data from three squares to illustrate the use of capture-recapture models in monitoring to obtain detectability-corrected estimates of species richness and trend. Species detectability averaged only 85%. Hence an estimated 15% of species present remained overlooked even after three visits. Within a square, changes in detectability for different years were of the same magnitude when surveys were conducted by the same observer as when they were by different observers. Estimates of trend were usually biased and community turnover was overestimated when based on enumeration. Here we use bird data as an illustration of methods. However, species detectability for any taxon is unlikely ever to be perfect or even constant across categories to be compared. Therefore, monitoring programs should correct for species detectability.

Basic and Applied Ecology↗
USGS2019

Biases in the literature on direct wildlife mortality from energy development

Comparing environmental impacts of different energy sources can inform energy investments and environmental conservation. Direct wildlife mortality from energy development receives substantial public and scientific attention, but it is unclear whether rigorous comparisons of mortality among energy sources are possible. To address this question, we compared availability of mortality studies among energy sources, wildlife groups, and regions, and assessed comparability of mortality indicators measured. Whereas wind and hydropower have received substantial mortality research exceeding their proportional contributions to global energy production, coal, oil and gas, and bioenergy have received fewer studies and are underrepresented relative to their contributions. Furthermore, research is biased toward birds and fish and North America and Europe, and there are inconsistencies among energy sources and limited replication of most indicators measured. These results indicate that rigorous comparisons of direct wildlife mortality among energy sources are not currently possible and highlight research needs for improving understanding of energy's environmental impacts.

BioScience↗
USGS2010

A rapid, strong, and convergent genetic response to urban habitat fragmentation in four divergent and widespread vertebrates

Background: Urbanization is a major cause of habitat fragmentation worldwide. Ecological and conservation theory predicts many potential impacts of habitat fragmentation on natural populations, including genetic impacts. Habitat fragmentation by urbanization causes populations of animals and plants to be isolated in patches of suitable habitat that are surrounded by non-native vegetation or severely altered vegetation, asphalt, concrete, and human structures. This can lead to genetic divergence between patches and in turn to decreased genetic diversity within patches through genetic drift and inbreeding. Methodology/Principal Findings: We examined population genetic patterns using microsatellites in four common vertebrate species, three lizards and one bird, in highly fragmented urban southern California. Despite significant phylogenetic, ecological, and mobility differences between these species, all four showed similar and significant reductions in gene flow over relatively short geographic and temporal scales. For all four species, the greatest genetic divergence was found where development was oldest and most intensive. All four animals also showed significant reduction in gene flow associated with intervening roads and freeways, the degree of patch isolation, and the time since isolation. Conclusions/Significance: Despite wide acceptance of the idea in principle, evidence of significant population genetic changes associated with fragmentation at small spatial and temporal scales has been rare, even in smaller terrestrial vertebrates, and especially for birds. Given the striking pattern of similar and rapid effects across four common and widespread species, including a volant bird, intense urbanization may represent the most severe form of fragmentation, with minimal effective movement through the urban matrix.

California↗
USGS2024

Geolocators, stable isotopes, and citizen science identify migratory timing, route, and spring molt of Smith’s Longspurs

Climate change is having a disproportionate impact on the Arctic. For Arctic breeding birds, basic knowledge of their annual cycle, specifically the timing, route, and movement behavior of migration, is needed to understand when and where populations may experience threats. We used a combination of geolocators and stable isotope analysis to identify route and timing of migration in Smith’s Longspurs ( Calcarius pictus ) that breed in Alaska’s Brooks Range. We trapped males on their breeding grounds from 2011 to 2014 and collected head feathers for stable isotopes of hydrogen (δ²H). We deployed 22 geolocators on a subset of individuals and retrieved four, which all overwintered in southern Texas. Individual start dates for fall migration based on geolocators were more variable than for the spring, and individuals were highly mobile while on their wintering grounds. Geolocators and stable isotope values were comparable across years and indicated that birds from the Brooks Range undergo their pre-nuptial molt in central Canada. We compared geolocator and stable isotope inferred locations to observations submitted to e-Bird and found that longspurs were distributed farther south during the winter months, but farther north during the spring than most eBird observations. Concurrent deployments of geolocator tags across Smith’s Longspurs’ breeding range would clarify whether migratory behaviors and routes are population-specific or shared widely across breeding locations.

Avian Conservation and Ecology↗
USGS1994

Communal roosting and foraging behavior of staging sandhill cranes

Each spring more than 300,000 Sandhill Cranes (Grus canadensis) roost communally at night in river channels in the Platte River Valley of Nebraska and disperse at dawn to forage in agricultural fields. Cranes with central roosts had activity ranges double the size of those with peripheral roosts; 42% of the birds changed activity ranges prior to the onset of migration. Minimum daily flight distance generally increased during the staging period. Cranes used native grassland and planted hayland more often than expected, relative to their percentage of occurrence, and fed longest there; cornfields were underutilized. These differences probably reflect, in part, (1) limited distribution of grasslands and haylands resulting in a greater energy expenditure to acquire protein in the form of macroinvertebrates and (2) wider distribution of cornfields with adequate energyrich foods but limited protein. Cranes probably forage more efficiently and conserve energy by following conspecifics from communal roosts to local feeding grounds, by settling in fields where foraging flocks are already present, and by establishing diurnal activity centers. Alert behavior varied with flock size but not as predicted from group size, presumably because predation of staging adult cranes is inconsequential.

The Wilson Bulletin↗
USGS2019

Evaluating community-level response to management actions across a diverse Hawaiian forest bird community

Although species‐specific approaches are necessary to understand the dynamics of individual species composing a community, they do not offer a framework for making optimal management decisions at the community level. Here, we present a simple framework for comparing the response of entire communities to multiple management scenarios. Our approach uses a weighted average of standardized species‐specific responses to produce a single integrative measure of the community response and employs mixed‐effect linear models to quantify the increase in the community response due to each management action, or combination of actions. We demonstrate our approach with a simulation study assessing the potential benefits of multiple management actions on the avian community of Hakalau Forest National Wildlife Refuge, Hawaiʻi, which is composed of eight native species with conservation status varying from endangered to least concern. Management actions considered included a reduction of avian malaria transmission risk, reducing rat predation, and increasing forest habitat. We used three different prioritization (weighting) schemes to assess whether the response to management actions differed along a conservation gradient (from endangered to least concern). We also investigated whether future changes in disease distribution as a result of climate change will alter the relationship between management practices and community response. Our community‐level analysis produced three important insights, highlighting the need to consider the response from multiple species to changing threats and management actions. First, increasing the amount of habitat always had the greatest positive impact on the avian community, regardless of the weighting scheme. Second, the community response to management was different under current vs. future conditions, with increased benefit in the future when disease risks were higher. Third, the response to management varied along the conservation gradient. Reducing malaria transmission risk in 2100 had the greatest benefit to endangered species, while increasing forest habitat had the greatest benefit to “least concern” species. However, reducing rat predation appeared to benefit a subset of species based on ecological factors unrelated to rarity, such as nest accessibility. Our approach is widely applicable using experimental, observational, or simulation‐based data, allowing managers to consider the response of all species while weighting their priority levels.

Hawaii↗