Biodiversity and global change

The availability of global datasets such as the IUCN Red List enables large-scale analyses for conservation. Important research questions include determining why some species are more threatened than others, identifying common threats to biodiversity, and quantifying protected area effectiveness.

Projected increase in threatened forest species richness [10]. Tropical regions with intact forest are expected to have particularly severe declines in biodiversity.

Relationships between the likelihood of species being threatened and body mass [7]. Large-bodied species often have high risk of extinction due to hunting by humans.

Large carnivore ecology and conservation

Studying Earth’s large carnivore species as a group offers the potential for new insights into predator conservation. Analyses can reveal the presence of co-occurring threats and highlight similarities and differences among these charasmatic, ecologically important species.

The 25 terrestrial large carnivore species.1 Many of these species are highly endangered and face threats including prey depletion and livestock-related conflict [3,13,18].

Percentage of large carnivores’ prey species with decreasing population trends [3]. Prey population declines motivate holistic conservation measures that protect both predator and prey species.

Bayesian statistics

Environmental data are often complex, and analyses may require combining dissimilar datasets and incorporating multiple levels of structure. Bayesian methods can be used to address these and other challenges, and are relatively straightforward to implement using probabilistic programming languages (e.g., Stan, BUGS/JAGS).

95% credible/confidence intervals for estimating prey-specific attack rates [12]. Compared to frequentist bootstrap-based approaches, Bayesian methods characterize uncertainty here in a more biologically realistic way.

Posterior distributions for attack rates and associated parameters [12]. Attack rate distributions were obtained by combining MCMC samples from feeding ratio, handling time, and abundance parameters.

  1. Cheetah photo credit: Peter Harrison (CC BY 2.0); see [18] for other photo credits.