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Identification of species' Biologically Important Areas (BIAs) is fundamental to conservation planning and species distribution models (SDMs) are a powerful tool commonly used to do this. Presence‐only data are increasingly being used to develop SDMs to aid the conservation decision‐making process. The application of presence‐only SDMs for marine species' is particularly attractive due to often logistical and economic costs of obtaining systematic species' distribution data. However, robust model validation is important for conservation management applications that require accurate and reliable species' occurrence data (e.g., spatially explicit risk assessments). This is commonly done using a random subset of the data and less commonly with fully independent test data. Here, we apply a spatial block cross‐validation (CV) approach to validate a MaxEnt presence‐only model using independent presence/absence survey data for a highly mobile, marine species (humpback whale, Megaptera novaengliae) in the Great Barrier Reef (GBR). A MaxEnt model was developed using opportunistic whale sightings (2003–2007) and then used to identify areas differing in habitat suitability (low, medium, high) to conduct a systematic, line‐transect, aerial survey (2012) and derive a density surface model. A spatial block CV buffering strategy was used to validate the MaxEnt model, using the opportunistic sightings as training data and independent aerial survey sightings data as test data. Moderate performance measures indicate MaxEnt was reliable in identifying the distribution patterns of a mobile whale species on their breeding ground, indicated by areas of high density aligned to areas of high habitat suitability. Furthermore, we demonstrate that MaxEnt models can be useful and cost‐effective for designing a sampling scheme to undertake systematic surveys that significantly reduces sampling effort. In this study, higher quality information on whale reproductive class (calf vs. non‐calf groups) was obtained that the presence‐only data lacked, while sampling only 18% of the GBR World Heritage Area. The validation approach using fully independent data provides greater confidence in the MaxEnt model, which indicates significant overlap with the main breeding ground of humpback whales and the inner shipping route. This is important when evaluating presence‐only models within certain conservation management applications, such as spatial risk assessments. [ABSTRACT FROM AUTHOR]

We analyzed recent survey data and mapped environmental variables integrated over a home range scale of 10 km(2) to model the distribution of fisher ( Martes pennanti) habitat in California, USA. Our goal was to identify habitat factors associated with the current distribution of fishers in California, and to test whether those factors differ for widely disjunct northern and southern populations. Our analyses were designed to probe whether poor habitat quality can explain the current absence of fishers in the historically occupied central and northern Sierra Nevada region that separates these two populations. Fishers were detected at 64/433 (14.8%) sample units, including 35/111 (32%) of sample units in the Klamath/Shasta region and 28/88 (32%) of sample units in the southern Sierra Nevada. Generalized additive models (GAM) that included mean annual precipitation, topographic relief, forest structure, and a spatial autocovariate term best predicted fisher detections over the species' recent historical range in California. Models derived using forest structure data from ground plots were comparable to models derived from Landsat Thematic Mapper imagery. Models for the disjunct Klamath/Cascades and southern Sierra Nevada populations selected different environmental factors and showed low agreement in the spatial pattern of model predictions. Including a spatial autocovariate term significantly improved model fits for all models except the southern Sierra Nevada. We cannot rule out dispersal or habitat in explaining the absence of fishers in the northern and central Sierra Nevada, but mapped habitat quality is low over much of the region. Landscapes with good fisher habitat may exist in rugged forested canyons of the currently unoccupied northern Sierra Nevada, but these areas are fragmented and at least 60 km from the nearest recent fisher detections.

Habitat use is often examined at a species or population level, but patterns likely differ within a species, as a function of the sex, breeding colony, and current breeding status of individuals. Hence, within-species differences should be considered in habitat models when analyzing and predicting species distributions, such as predicted responses to expected climate change scenarios. Also, species' distribution data obtained by different methods (vessel-survey and individual tracking) are often analyzed separately rather than integrated to improve predictions. Here, we eventually fit generalized additive models for Streaked Shearwaters Calonectris leucomelas using tracking data from two different breeding colonies in the Northwestern Pacific and visual observer data collected during a research cruise off the coast of western Japan. The tracking-based models showed differences among patterns of relative density distribution as a function of life history category (colony, sex, and breeding conditions). The integrated tracking-based and vessel-based bird count model incorporated ecological states rather than predicting a single surface for the entire species. This study highlights both the importance of including ecological and life history data and integrating multiple data types (tag-based tracking and vessel count) when examining species-environment relationships, ultimately advancing the capabilities of species distribution models. [ABSTRACT FROM AUTHOR]

The article presents a study on the efficient use of light detection and ranging (LIDAR)-derived measurements to measure the vegetation structure for passerine birds in riparian habitat at the Central Valley in California. The use of LIDAR imagery is capable of generating estimates of canopy height, stem diameter and biomass. Moreover, the study intends to support the predictive performance of vegetation measurements of LIDAR imagery at one hectare scale.

This article reports that the natural resources management at large spatial and temporal scales requires tools for projecting the effects of natural and anthropogenic disturbances on population, community, and ecosystem processes. Computer simulation allows modeling of scenarios to test the effect of disturbance regimes on landscape patterns and, in turn, on population dynamics of wildlife species of management concern. In many cases, these simulations use metapopulation models that incorporate aspects of a dynamic landscape, such as changing carrying capacities of habitat patches through time. The U.S. Forest Service identified Bell's Sage Sparrow, a California Species of Special Concern, as currently at moderate risk of population decline, although population trends are unknown. It was also designated as a species best conserved though landscape-level habitat management. The Bell's Sage Sparrow is associated with coastal sage scrub vegetation, a plant formation dominated by small, drought-deciduous shrubs, as well as open chaparral habitats in the interior foothills, especially young-aged, recently burned chaparral.

The article reports on models of habitat distribution. It mentions the nonviability of research on distributions at fine resolutions over landscapes due to lack of time and resources. It also notes its utilization for evaluating the possible effects of poor water table depth and environmental changes on the distribution of the butterfly Plebejus argus.

The article presents a study on the wildlife responses on the landscape change at the Willamette River Basin in Oregon. Mentioned is the use of models in determining the balance between parsimony and biological realism. Investigated is the percentage change in habitat quality as well as the percentage change in population size of species.

The article presents a study which uses habitat models to predict the frequency of occurrence of epiphytic lichen species in a forested landscape under two alternative plans. It cites the plans which include plan patterned in part after natural disturbance regimes and a literal application of standard prescriptions in the Northwest Forest Plan. It mentions that the study defines structural classes by combinations of young cohort age, overstory retention of remnant trees, and stream position.

The article discusses effects of landscape structure in Florida scrub lizard (Sceloporus woodi) in naturally fragmented habitat. Topics discussed include poor dispersal ability relative to degree of isolation of patches accounting for large gaps in Sceloporus' distribution, application of model to Cnemidophorus sexlineatus for examining applicability of the scrub lizard model to other species, and use of regression models for identifying abundance of a variety of species.