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The Key Largo woodrat (Neotoma floridana smalli) is an endangered rodent with a restricted geographic range and small population size. Establishing an efficient monitoring program of its abundance has been problematic; previous trapping designs have not worked well because the species is sparsely distributed. We compared Key Largo woodrat abundance estimates in Key Largo, Florida, USA, obtained using trapping point transects (TPT) and spatially explicit capture–recapture (SECR) based on statistical properties, survey effort, practicality, and cost. Both methods combine aspects of distance sampling with capture–recapture, but TPT relies on radiotracking individuals to estimate detectability and SECR relies on repeat capture information to estimate densities of home ranges. Abundance estimates using TPT in the spring of 2007 and 2008 were 333 woodrats (CV = 0.46) and 696 (CV = 0.43), respectively. Abundance estimates using SECR in the spring, summer, and winter of 2007 were 97 (CV = 0.31), 334 (CV = 0.26), and 433 (CV = 0.20) animals, respectively. Trapping point transects used approximately 960 person‐hours and 1,010 trap‐nights/season. Spatially explicit capture–recapture used approximately 500 person‐hours and 6,468 trap‐nights/season. Significant time was saved in the SECR survey by setting large numbers of traps close together, minimizing time walking between traps. Trapping point transects were practical to implement in the field, and valuable auxiliary information on Key Largo woodrat behavior was obtained via radiocollaring. In this particular study, detectability of the woodrat using TPT was very low and consequently the SECR method was more efficient. Both methods require a substantial investment in survey effort to detect any change in abundance because of large uncertainty in estimates. [ABSTRACT FROM AUTHOR]

We coordinated a large-scale evaluation of northern bobwhite (Colinus virginianus) population response to establishment of 9-m to 37-m linear patches (buffers) of native herbaceous vegetation along row-crop field margins as part of the Conservation Reserve Program practice Habitat Buffers for Upland Birds (CP33). We compared northern bobwhite covey densities on 1,088 paired row-crop fields with and without native herbaceous buffers in 13 states during autumn, 2006–2008. We used a 2-stage random effects modeling approach that incorporates the effective area as an offset in generalized linear mixed models to assess regional relationships among autumn bobwhite covey densities and covariates of field type (i.e., fields with vs. without native herbaceous buffers), ecological region, year, survey week, and contracted vegetative cover (i.e., planting native grasses and forbs vs. establishing through natural regeneration). Covey density was correlated with year and interaction effects of field type and ecological region. The year effect suggested annual variation in covey densities, whereas the field type by ecological region interaction suggested covey response to buffers was dependent on spatial location, likely reflecting differences in buffer establishment, succession, and characteristics of the surrounding landscape among regions. Mean fitted covey density on fields across all survey sites was 0.047 (±0.008 bootstrap standard error [BSE]) and 0.031?coveys/ha (±0.003 BSE) on row-crop fields with and without herbaceous buffers, respectively. Covey density was greater on fields with buffers relative to matched, comparison fields without buffers in the Mississippi Alluvial Valley (241%; P?

ABSTRACT We quantified changes in density of red squirrels (Tamiasciurus hudsonicus) in response to prescribed fire in mixed coniferous forests of Idaho and Washington, USA, using a Before-After-Control-Impact design. We found no evidence that low-severity prescribed fires affected density of red squirrels; we estimated the change in red squirrel densities due to prescribed fire as -0.15 squirrels/ha (95% CI = -0.405–0.105). Squirrel density did, however, increase with increasing live tree density, shrub cover, and density of large downed logs, and varied across years and states. These results indicate that land managers implementing prescribed fire treatments to reduce fuel loads on public lands can reduce the impacts of fire on squirrel populations by formulating prescriptions to retain large live trees and large downed logs.

The desire to predict the consequences of global environmental change has been the driver towards more realistic models embracing the variability and uncertainties inherent in ecology. Statistical ecology has gelled over the past decade as a discipline that moves away from describing patterns towards modelling the ecological processes that generate these patterns. Following the fourth International Statistical Ecology Conference (1–4 July 2014) in Montpellier, France, we analyse current trends in statistical ecology. Important advances in the analysis of individual movement, and in the modelling of population dynamics and species distributions, are made possible by the increasing use of hierarchical and hidden process models. Exciting research perspectives include the development of methods to interpret citizen science data and of efficient, flexible computational algorithms for model fitting. Statistical ecology has come of age: it now provides a general and mathematically rigorous framework linking ecological theory and empirical data.

Zigzag survey lines are frequently used in shipboard and aerial line transect surveys of animal populations. Analysis proceeds assuming that coverage probability through the survey region is uniform. We show that the two types of zigzag design that are in wide use do not generally have this property, and explore the degree of bias in abundance estimates that can be anticipated. We construct a zigzag design for convex survey regions that has even coverage probability with respect to distance along a design axis. We also provide Horvitz-Thompson estimators that allow coverage probability to vary by location through the survey region.