The biodiversity crisis is still accelerating, despite increasing efforts by the international community. Estimating animal abundance of critical importance to assess, for example, consequences land-use change and invasive species on community composition, or effectiveness conservation interventions. Various approaches have been developed estimate unmarked populations. Whereas these differ in m...

One goal of acoustic-based abundance estimates is to accurately preserve spatial distributions of organism density and size within survey data. We simulated spatiallyrandom and spatially-autocorrelated fish density and bs distributions to quantify variance in density, abundance, and backscattering cross-sectional area estimates, and to examine the sensitivity of abundance estimates to organism ...

Knowledge of animal abundance is fundamental to many ecological studies. Frequently, researchers cannot determine true abundance, and so must estimate it using a method such as mark-recapture or distance sampling. Recent advances in abundance estimation allow one to model heterogeneity with individual covariates or mixture distributions and to derive multimodel abundance estimators that explici...

Species distribution models (SDMs) are a general suite of models that relate the frequency of species occurrences (presence only or presence/absence) to sets of environmental variables. These relationships can then be used to generate predictions of the geographic areas where the species are expected to occur, making SDMs powerful and widely used tools in conservation biology, biogeography and ...

Avian surveys using point sampling for abundance estimation have either focused on distance sampling or more commonly mark-recapture to correct for detection bias. Combining mark-recapture and distance sampling (MRDS) has become an effective tool for line transects, but it has been largely ignored in point sampling literature. We describe MRDS and show that the previously published methods for ...