Melding Wildlife Surveys to Improve Conservation Inference
Integrated models are a popular tool for analyzing species of conservation concern. Species of conservation concern are often monitored by multiple entities that generate several datasets. Individually, these datasets may be insufficient for guiding management due to low spatio-temporal resolution, biased sampling, or large observational uncertainty. Integrated models provide an approach for assimilating multiple datasets in a coherent framework that can compensate for these deficiencies. While conventional integrated models have been used to assimilate count data with surveys of survival, fecundity, and harvest, they can also assimilate ecological surveys that have differing spatio-temporal regions and observational uncertainties. Motivated by independent aerial and ground surveys of lesser prairie-chicken abundance, we developed an integrated modeling approach that assimilates density estimates derived from surveys with distinct sources of observational error into a joint framework that provides shared inference on spatio-temporal trends. For implementation, we model these data using a Bayesian Markov melding approach and apply several data augmentation strategies for efficient sampling. Our integrated model decreased uncertainty in annual density estimates, facilitated prediction at unsampled regions, and quantified the inferential cost associated with reduced survey effort.
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