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At least 505 records · Page 28Linked to original sources
USGS1999

Picking up the pieces: Conserving remnant natural areas in the post-industrial landscape of the Calumet Region

The Calumet Region was shaped by geologic forces, succession, and interacting biomes converging on a unique natural landscape. Over the past 4500 years, a strand plain has formed to the north of a geologic area called Toleston Beach. Sequential and differential primary succession of dune and swale communities in this region allowed species from different biomes to interact freely. In the mid-nineteenth century, commerce and settlement drastically changed the area, and natural areas were fragmented, manipulated, and degraded by cultural intrusions and industrialization. Despite the near obliteration of dune and swale habitat, small fragments of natural land escaped destruction. These native fragments maintained some semblance of the landscape that once covered the region. Currently, these native fragments are threatened by the lingering intrusion of historic contamination and the continuing presence of industry and commerce. Restoration and conservation of these remnants will need to be a process of integrating biological diversity goals into the landscape of the industrialized region through planning and design. We outline here the natural history of the region, the philosophical rationale for conservation, and possible approaches for integrating and maintaining these valuable remnant resources and processes.

Illinois, Indiana, Michigan↗
USGS2005

Amphibian occurrence and aquatic invaders in a changing landscape: Implications for wetland mitigation in the Willamette Valley, Oregon

Despite concern about the conservation status of amphibians in western North America, few field studies have documented occurrence patterns of amphibians relative to potential stressors. We surveyed wetland fauna in Oregon's Willamette Valley and used an information theoretic approach (AIC) to rank the associations between native amphibian breeding occurrence and wetland characteristics, non-native aquatic predators, and landscape characteristics in a mixed urban-agricultural landscape. Best predictors varied among the five native amphibians and were generally consistent with life history differences. Pacific tree frog (Pseudacris regilla) and long-toed salamander (Ambystoma macrodactylum) occurrence was best predicted by the absence of non-native fish. Northern red-legged frog (Rana a. aurora) and northwestern salamander (Ambystoma gracile) were most strongly related to wetland vegetative characteristics. The occurrence of rough-skinned newts (Taricha granulosa), a migratory species that makes extensive use of terrestrial habitats, was best predicted by greater forest cover within 1 km. The absence of non-native fish was a strong predictor of occurrence for four of the five native species. In contrast, amphibians were not strongly related to native fish presence. We found little evidence supporting negative effects of the presence of breeding populations of bullfrog (Rana catesbeiana) on any native species. Only the two Ambystoma salamanders were associated with wetland permanence. Northwestern salamanders (which usually have a multi-year larval stage) were associated with permanent waters, while long-toed salamanders were associated with temporary wetlands. Although all the species make some use of upland habitats, only one (rough-skinned newt) was strongly associated with surrounding landscape conditions. Instead, our analysis suggests that within-wetland characteristics best predict amphibian occurrence in this region. We recommend that wetland preservation and mitigation efforts concentrate on sites lacking non-native fish for the conservation of native amphibians in the Willamette Valley and other western lowlands.

Wetlands↗
USGS2000

Painted Bunting Breeding Bird Survey trends associated with landscape changes in Georgia and South Carolina

Landscape changes during the first 3 decades of the Breeding Bird Survey (BBS) may account for the Painted Bunting's declining population trend. In the southeastern U.S., it is estimated that this bunting has declined 3.5 % per year since 1966. I collected landscape data centered on identical 5-stop areas (n = 33, 306 ha each) of the BBS during early (1960s - 1970s) and late decades (1980s - 1990s). Peak 30-yr counts for Painted Buntings were found at the center of the 5-stop areas. I used stepwise multiple regression analysis to model the mean number of Painted Buntings (in the area during 3 yr, dependent variable) associated with landscape metrics (independent variables). During the early decades the average amount of edge on developed land (p = 0.10), average patch size of agriculture land (p = 0.01), average size of shrub-scrub and young forest (p = 0.09), and average amount of edge for emergent wetlands (p = 0.03) explained 40% of the variation in Painted Buntings counts. In the late decades average amount of edge on developed land (p = 0.04) and average amount of edge on emergent wetlands (p = 0.005) explained 35% of the variation in Painted Bunting counts. Large losses of agricultural land (proportion = 0.177 to 0.094), which was developed or converted to intensively managed pin plantations, may have reduced potential bunting breeding habitat. Shrub-scrub and young forest habitat was constant (proportion = 0.136 to 0.134) but did not affect mean counts of buntings in the late decades. Protected emergent wetlands remained constnat also from the early to late decades (proportion = 0.056 to 0.06) and may provide habitat to maintain a smaller Painted Bunting population. At this time, it's unclear how develped land, which is increasing (proportion = 0.036 to 0.088), may be affecting the Painted Bunting population in GS and SC.

Book chapter↗
USGS1999

Assessment of landscape correlates of Eastern hemlock decline due to hemlock woolly adelgid

Eastern hemlock ( Tsuga canadensis ) is in decline throughout its range in the eastern US due to infestation by an exotic insect pest, the hemlock woolly adelgid ( Adelges tsugae ). In Shenandoah National Park, the hemlock woolly adelgid (HWA) rapidly killed many stands of hemlock after first appearing in the late-1980’s, while having only minor impact in other stands. At present, few investigators have examined the mechanisms that produce this discontinuous impact, although landscape factors are predicted to play a major role (Orwig and Foster, 1998: Perry 1988). In an effort to address possible landscape correlates to hemlock decline, we conducted a preliminary analysis of 5 years of hemlock health estimates in comparison to measures of terrain, stand isolation, and potential dispersal corridors at the stand level. We found that elevation, slope, light conditions, and distance to streams all exhibited relatively strong correlation with hemlock decline, although the relationship varied by year. In addition, there appears to be some evidence of spatial autocorrelation in decline, suggesting that similar environmental conditions are either controlling the adelgid or making hemlock stands more susceptible to HWA. We are using the results of this preliminary analysis to guide more detailed efforts aimed at modeling hemlock stand vulnerability as a result of site, landscape, and regional factors.

Virginia↗
USGS1998

Landscape and fine scale habitat associations of the Loggerhead Shrike

This study was conducted to determine landscape and fine-scale vegetative variables associated with breeding Loggerhead Shrikes (Lanius ludovicianus) on Fort Riley Military Reservation, Kansas. Because Fort Riley is an Army training site, the influences of training disturbance to the vegetation, and range management practices on bird habitat patterns were also investigated. Breeding birds were surveyed in 1995 and 1996 using point counts. Survey plots were identified, a priori, at the landscape scale as either grassland, savannah, or woodland edge according to cover by woody vegetation. In 1996, fine-scale habitat at survey points and at bird use sites was measured and a principal components analysis used to characterize the fine-scale herbaceous vegetation structure. A military disturbance index was developed to quantify the severity of vehicle disturbance to the vegetation at survey and bird use sites. Shrikes were associated with savannah habitat at the landscape scale. Sites used by Loggerhead Shrikes were characterized at the fine-scale by tall, sparse, structurally heterogeneous herbaceous vegetation with high standing dead plant cover and low litter cover. At the fine-scale, tree and shrub density did not differ between sites used and not used by shrikes. Used sites did not differ from survey sites with respect to military training disturbance, hay harvest, or the number of years since a site was last burned. Our results in this study suggest that the shifting mosaic of vegetation on Fort Riley resulting from training and range management practices maintains adequate habitat for breeding shrikes.

The Wilson Bulletin↗
USGS2000

Regoliths of the middle-Atlantic Piedmont and evolution of a polymorphic landscape

The regolith overlying the alumino-silicate rocks of the middle-Atlantic Piedmont Province consists primarily of saprolite with a thin veneer of diamictons of colluvial origin. Thickness and distribution of the saprolite is related to landform and lithology. For example, on uplands isovolumetric weathering of the Loch Raven Schist produces saprolite averaging 55 ft (17 m) thick. On Port Deposit Gneiss, saprolite beneath uplands averages 42 ft (13 m) in thickness. The saprolite results from the reaction of alumino-silicate rocks with through-flowing groundwater. Chemical weathering of the rock results in clay and resistate minerals, residual rock layers, corestones, and pinnacles. Surface erosion of saprolite with quartzite and metagraywacke residual layers may produce a 'washboard' topography. Surface erosion of a metagabbro saprolite containing corestones and pinnacles results in a surface with lag deposits of corestones and emergent pinnacles. The diamicton material comes from the underlying saprolite, weathered rock and bedrock. Generally, diamictons are thinner on uplands and upper slopes, and thicker at the base of slopes and in hollows and gathering areas of first-order streams. The saprolite and colluvium reflect response of geomorphic processes (chemical weathering, fluvial incision, and periglacial processes) to rock lithology and landscape. The modifications to the landscape have been driven by neotectonic crustal warping and alternating periglacial-humid temperate climates. Altogether these varied interactions have resulted in a Holocene polymorphic landscape.

Southeastern Geology↗
USGS2013

Mapping landscape phenology preference of yellow-billed cuckoo with AVHRR data

We mapped habitat for threatened Yellow-billed Cuckoo (Coccycus americanus occidentalis) in the State of Arizona using the temporal greenness dynamics of the landscape, or the landscape phenology. Landscape phenometrics were derived from Advanced Very High Resolution Radiometer (AVHRR) Normalized Difference Vegetation Index (NDVI) data for 1998 and 1999 by using Fourier harmonic analysis to analyze the waveform of the annual NDVI profile at each pixel. We modeled the spatial distribution of Yellow-billed Cuckoo habitat by coupling the field data of Cuckoo presence or absence and point-based samples of riparian and cottonwood-willow vegetation types with satellite phenometrics for 1998. Models were validated using field and satellite data collected in 1999. The results indicate that Yellow-billed Cuckoo occupy locations within their preferred habitat that exhibit peak greenness after the start of the summer monsoon and are greener and more dynamic than “average” habitat. Identification of preferred phenotypes within recognized habitat areas can be used to refine habitat models, inform predictions of habitat response to climate change, and suggest adaptation strategies.

Arizona↗
USGS2013

A landscape-based assessment of climate change vulnerability for all native Hawaiian plants

In Hawaiʽi and elsewhere, research efforts have focused on two main approaches to determine the potential impacts of climate change on individual species: estimating species vulnerabilities and projecting responses of species to expected changes. We integrated these approaches by defining vulnerability as the inability of species to exhibit any of the responses necessary for persistence under climate change (i.e., tolerate projected changes, endure in microrefugia, or migrate to new climate-compatible areas, but excluding evolutionary adaptation). To operationalize this response-based definition of species vulnerability within a landscape-based analysis, we used current and future climate envelopes for each species to define zones across the landscape: the toleration zone; the microrefugia zone; and the migration zone. Using these response zones we calculated a diverse set of factors related to habitat area, quality, and distribution for each species, including the amount of habitat protection and fragmentation and areas projected to be lost to sea-level rise. We then calculated the probabilities of each species exhibiting these responses using a Bayesian network model and determined the overall climate change vulnerability of each species by using a vulnerability index. As a first iteration of a response-based species vulnerability assessment (VA), our landscape-based analysis effectively integrates species-distribution models into a Bayesian network-based VA that can be updated with improved models and data for more refined analyses in the future. Our results show that the species most vulnerable to climate change also tend to be species of conservation concern due to non-climatic threats (e.g., competition and predation from invasive species, land-use change). Also, many of Hawaiʽi’s taxa that are most vulnerable to climate change share characteristics with species that in the past were found to be at risk of extinction due to non-climatic threats (e.g., archipelago endemism, single-island endemism). Of particular concern are the numerous species that have no compatible-climate areas remaining by the year 2100. Species primarily associated with dry forests have higher vulnerability scores than species from any other habitat type. When examined at taxonomic levels above species, low vulnerabilities are concentrated in families and genera of generalists (e.g., ferns or sedges) and typically associated with mid-elevation wet habitats. Our results replicate findings from other regions that link higher species vulnerability with decreasing range size. This species VA is possibly the largest in scope ever conducted in the United States with over 1000 species considered, 319 of which are listed as endangered or threatened under the U.S. Endangered Species Act, filling a critical knowledge gap for resource managers in the region. The information in this assessment can help prioritize species for special conservation actions, guide the management of conservation areas, inform the selection of research and monitoring priorities, and support adaptive management planning and implementation.

Hawai'i↗
USGS1986

Changing landscapes and the cosmopolitism of the eastern Colorado avifauna

The avifauna of continental North America has changed dramatically since colonial times. Excessive hunting contributed, at least in part, to the extinction of birds such as the great auk ( Pinguinus impennis ) and passenger pigeon ( Ectopistes migratorius ), while more recently organochlorine insecticide residues have resulted in drastic reductions in numbers of brown pelicans ( Pelecanus occidentalis ) (Anderson et al. 1975) and other species. Generally, however, vertebrate populations change in direct response to changes in their habitats. For example, herring gulls ( Larus argentatus ) have increased in numners (Kadlec and Drury 1968) with urbanization of the New England coastline, in the same locations formerly occupied by the extinct heath hen ( Tympanuchus cupido cupido ). Also, passerine birds of forest interiors have declined in numbers with fragmentation of the eastern deciduous forest into small stands; this fragmentation has led to increases in numbers of edge species (Robbins 1979, Ambuel and Temple 1983). Even subtle community shifts can introduce new competitive processes that can augment population changes among species (Brittingham and Temple 1983). Such studies of broad-scale changes in vegetative communities and their influence on native wildlife species have fostered the recent topical emphasis on "conservation biology" (Soule and Wilcox 1980, Soule 1985) and "landscape ecology" (Burgess and Sharpe 1981, Harris 1984:25-43). As changes in landscapes are causing subtle (but potentially dramatic) changes in the distribution of native species, conservation biologists are finding that mere presence-absence data on populations, or even accurate information on reproductive success, is inadequate to evaluate management activities or environmental perturbations. The principles of "conservation genetics" are attracting interest in the management of natural preserves especially (Schonewald-Cox et al. 1983). Changing patterns in landscape complexion or genetic makeup of a population are difficult to detect locally. Contemporary issues in the conservation of native species demand regional and continental perspectives (Samson and Knopf 1982). Thus, management activities at specific sites are often viewed as short-sighted by planners and conservation critics. This paper illustrates how these contemporary theories can influence a local conservation perspective. That perspective is developed around historical processes that have led to cosmopolitism of the local avifauna on the Colorado Division of Wildlife's South Platte Wildlife Management Area (SPWMA) near Crook, Colorado.

Colorado↗
USGS1989

Terrain, vegetation, and landscape evolution of the R4D research site, Brooks Range Foothills, Alaska

Maps of the vegetation and terrain of a 22 km2 area centered on the Department of Energy (DOE) R4D (Response, Resistance, Resilience to and Recovery from Disturbance in Arctic Ecosystems) study site in the Southern Foothills Physiographic Province of Alaska were made using integrated geobotanical mapping procedures and a geographic-information system. Typical land forms and surface f orms include hillslope water tracks, Sagavanirktok-age till deposits, nonsorted stone stripes, and colluvial-basin deposits. Thirty-two plant communities are described; the dominant vegetation (51% of the mapped area) is moist tussock-sedge, dwarf-shrub tundra dominated by Eriophorum vaginatum or Carex bigelowii. Much of the spatial variation in the mapped geobotanical characters reflects different-aged glaciated surfaces. Shannon-Wienerin dices indicate that the more mature landscapes, represented by retransported hillslope deposits and basin colluvium, are less heterogeneous than newer landscapes such as surficial till deposits and floodplains. A typical toposequence on a mid-Pleistocene-age surface is discussed with respect to evolution of the landscape. Thick Sphagnum moss layers occur on lower hillslopes, and the patterns of moss-layer development, heat flux, active layer thickness, and ground-ice are seen as keys to developing thermokarst-susceptibility maps.

Alaska↗
USGS2012

Genetic variation reveals influence of landscape connectivity on population dynamics and resiliency of western trout in disturbance-prone habitats

Salmonid fishes have evolved and persisted in dynamic ecosystems where disturbance events vary in frequency, magnitude, timing, and duration, as well as the specific nature of associated effects (e.g., changes in thermal or flow regimes, geomorphology, or water chemistry). In the western United States, one of the major drivers of disturbance in stream ecosystems is fire. Although there is a growing consensus that fish populations can ultimately benefit from the productive and heterogeneous habitats created by fire, to persist they obviously have to withstand the immediate and shorter-term effects of fire, which can reduce or even extirpate local populations. Movement among interconnected stream habitats is thought to be an important strategy enabling persistence during and following fire, and there is mounting concern that the extensive isolation of salmonid populations in fragmented habitats is reducing their resiliency to fire. In spite of this concern, there are few direct observations of salmonid responses to fire. In fact, guidance is based largely on a broader understanding of the influences of landscape structure and disturbance in general on salmonid fishes, and there is considerable uncertainty about how best to manage for salmonid resilience to wildfire. Studies are limited by the difficult logistics of following fish responses in the face of unpredictable events such as wildfires. Therefore, BACI (Before-After-Control-Impact) study designs are nearly impossible, and replication is similarly challenging because fires are often low-frequency events. Furthermore, conventional ecological study approaches (e.g., studies of fish distribution, abundance, life histories, and movement) are logistically difficult to implement. Overall, a major challenge to understanding resilience of salmonid populations in fire-prone environments is related to moving beyond localized case studies to those with broader applicability in wildfire management . Genetic data can be useful for overcoming many of the limitations inherent in ecological studies. Here we review several case studies of western trout where population genetic data have provided insight about fish responses to fragmentation and disturbance more generally, and specifically in relation to fire. Results of these studies confirm the importance of movement and landscape connectivity for ensuring fish persistence in fire-prone landscapes, and highlight the usefulness of genetic approaches for broad-scale evaluation and monitoring of population responses to fire and related management actions.

Technical Report↗
USGS2015

Defining conservation targets on a landscape-scale

Conservation planning, the process of deciding how to protect, conserve, enhance and(or) minimize loss of natural and cultural resources, is a fundamental process to achieve conservation success in a time of rapid environmental change. Conservation targets, the measurable expressions of desired resource conditions, are an important tool in biological planning to achieve effective outcomes. Conservation targets provide a focus for planning, design, conservation action, and collaborative monitoring of environmental trends to guide landscape-scale conservation to improve the quality and quantity of key ecological and cultural resources. It is essential to have an iterative and inclusive method to define conservation targets that is replicable and allows for the evaluation of the effectiveness of conservation targets over time. In this document, we describe a process that can be implemented to achieve landscape-scale conservation, which includes defining conservation targets. We also describe what has been accomplished to date (September 2015) through this process for the Peninsular Florida Landscape Conservation Cooperative (PFLCC).

Florida↗
USGS2016

Modeling the effects of land cover and use on landscape capability for urban ungulate populations

Expanding ungulate populations are causing concerns for wildlife professionals and residents in many urban areas worldwide. Nowhere is the phenomenon more apparent than in the eastern US, where urban white-tailed deer (Odocoileus virginianus) populations are increasing. Most habitat suitability models for deer have been developed in rural areas and across large (>1000 km2) spatial extents. Only recently have we begun to understand the factors that contribute to space use by deer over much smaller spatial extents. In this study, we explore the concepts, terminology, methodology and state-of-the-science in wildlife abundance modeling as applied to overabundant deer populations across heterogeneous urban landscapes. We used classified, high-resolution digital orthoimagery to extract landscape characteristics in several urban areas of upstate New York. In addition, we assessed deer abundance and distribution in 1-km2 blocks across each study area from either aerial surveys or ground-based distance sampling. We recorded the number of detections in each block and used binomial mixture models to explore important relationships between abundance and key landscape features. Finally, we cross-validated statistical models of abundance and compared covariate relationships across study sites. Study areas were characterized along a gradient of urbanization based on the proportions of impervious surfaces and natural vegetation which, based on the best-supported models, also distinguished blocks potentially occupied by deer. Models performed better at identifying occurrence of deer and worse at predicting abundance in cross-validation comparisons. We attribute poor predictive performance to differences in deer population trajectories over time. The proportion of impervious surfaces often yielded better predictions of abundance and occurrence than did the proportion of natural vegetation, which we attribute to a lack of certain land cover classes during cold and snowy winters. Merits and limitations of our approach to habitat suitability modeling are discussed in detail.

Book chapter↗
USGS2017

The Conservation Efforts Database: Improving our knowledge of landscape conservation actions

The Conservation Efforts Database (CED) is a secure, cloud-based tool that can be used to document and track conservation actions across landscapes. A recently released factsheet describes this tool ahead of the rollout of CED version 2.0. The CED was developed by the U.S. Fish and Wildlife Service, the USGS, and the Great Northern Landscape Conservation Cooperative to support the 2015 Endangered Species Act status review for greater sage-grouse. Currently, the CED accepts policy-level data, such as Land Use Plans, and treatment level data, such as conifer removals and post-fire recovery efforts, as custom spatial and non-spatial records. In addition to a species assessment tool, the CED can also be used to summarize the extent of restoration efforts within a specific area or to strategically site conservation actions based on the location of other implemented actions. The CED can be an important tool, along with post-conservation monitoring, for implementing landscape-scale adaptive management.

Report↗
USGS2017

Dynamic optimization of landscape connectivity embedding spatial-capture-recapture information

Maintaining landscape connectivity is increasingly important in wildlife conservation, especially for species experiencing the effects of habitat loss and fragmentation. We propose a novel approach to dynamically optimize landscape connectivity. Our approach is based on a mixed integer program formulation, embedding a spatial capture-recapture model that estimates the density, space usage, and landscape connectivity for a given species. Our method takes into account the fact that local animal density and connectivity change dynamically and non-linearly with different habitat protection plans. In order to scale up our encoding, we propose a sampling scheme via random partitioning of the search space using parity functions. We show that our method scales to realworld size problems and dramatically outperforms the solution quality of an expectation maximization approach and a sample average approximation approach.

Conference Paper↗
USGS2014

Making decisions in complex landscapes: Headwater stream management across multiple federal agencies

Headwater stream ecosystems are vulnerable to numerous threats associated with climate and land use change. In the northeastern US, many headwater stream species (e.g., brook trout and stream salamanders) are of special conservation concern and may be vulnerable to climate change influences, such as changes in stream temperature and streamflow. Federal land management agencies (e.g., US Fish and Wildlife Service, National Park Service, USDA Forest Service, Bureau of Land Management and Department of Defense) are required to adopt policies that respond to climate change and may have longer-term institutional support to enforce such policies compared to state, local, non-governmental, or private land managers. However, federal agencies largely make management decisions in regards to headwater stream ecosystems independently. This fragmentation of management resources and responsibilities across the landscape may significantly impede the efficiency and effectiveness of conservation actions, and higher degrees of collaboration may be required to achieve conservation goals. This project seeks to provide an example of cooperative landscape decision-making to address the conservation of headwater stream ecosystems. We identified shared and contrasting objectives of each federal agency and potential collaboration opportunities that may increase efficient and effective management of headwater stream ecosystems in two northeastern US watersheds. These workshops provided useful insights into the adaptive capacity of federal institutions to address threats to headwater stream ecosystems. Our ultimate goal is to provide a decision-making framework and analysis that addresses large-scale conservation threats across multiple stakeholders, as a demonstration of cooperative landscape conservation for aquatic ecosystems. Additionally, we aim to provide new scientific knowledge and a regional perspective to resource managers to help inform local management decisions.

Maine, New Hampshire, Virginia, West Virginia↗
USGS2008

Late Pleistocene through Holocene landscape evolution of the White River Badlands, South Dakota

Badlands are common arid and semiarid landscapes long recognized in slope development and erosion rate studies by preeminent geomorphologists including Gilbert, Davis, and Schumm. The trip described here will examine in detail Quaternarystrata and landscape evolution in arguably the most famous badlands, the White River Badlands of South Dakota, which were pivotal during development of vertebrate paleontology in North America. Geologists have collected fossils from the White River Group there nearly every field season since the mid-1800s; however, until recently, little work was reported on the extensively exposed Quaternary strata. The White River Badlands are also a proposed dust source for the widespread PeoriaLoess of the Central Great Plains. The research highlighted on this trip includes (1) luminescence and radiocarbon ages from late Pleistocene through Holocene eolian sand, (2) radiocarbon ages from Holocene eolian cliff-top deposits, (3) luminescenceages from late Pleistocene fluvial silts, (4) radiocarbon ages of late Holocene fluvial silts, and (5) cosmogenic ages on ventifacts from the adjoining upper prairie. These new studies will facilitate discussions, including (1) late Quaternary paleoenvironments,(2) late Quaternary fluvial incision rates and episodes, (3) up-wind sediment supply of late Quaternary nonglaciogenic loess, (4) landscape evolution spanning late Pleistocene tableland through late Holocene sod table development, and (5) modern erosion-pedimentation rates.

South Dakota↗
USGS2020

Using biodiversity metrics to guide conservation planning in altered tropical landscapes

Biodiversity metrics are frequently used to guide conservation planning because they can summarize biogeographical attributes of plant and animal communities quickly and at multiple scales. Attributes include habitat features of high conservation value, representativeness, and redundancy of biological communities. We conducted a rapid ecological assessment of resident avian species in the west-central mountainous region of Puerto Rico in 2015, a landscape dominated by coffee cultivation. We focused on this landscape because shade-grown and restored shade-grown coffee plantations offer an opportunity to complement protected habitat (e.g., reserves) to enhance species persistence. We used species richness, which tallies the number of unique species, and a quadratic entropy index of diversity, which incorporates interspecific taxonomic differentiation to evaluate species representativeness and redundancy across sun- and shade-grown coffee plantations and secondary forest. We surveyed 120 sites, calculating both metrics using species-specific occupancy probabilities estimated from community-level occupancy models. Species representativeness and redundancy were high as neither metric was able to discriminate among habitat types, possibly because plant communities were redundant, and the avian community was dominated by species adept at exploiting altered habitats. Similarly, we could not discriminate among avian communities modeling each biodiversity metric as a function of site-specific habitat covariates. Our findings and available knowledge on avian community demographics suggest that conservation strategies could couple protected habitat (e.g., reserves) and restored habitat (e.g., coffee plantations) to enhance species diversity and persistence across human-modified landscapes.

Caribbean Naturalist↗