Using citizen science data in integrated population models to inform conservation decision-making

Abstract

Analysis of animal population status and change are core elements of ecological research and critical for prioritizing conservation actions. Traditionally, count-based data from structured surveys have been the main source of information used to estimate trends and changes in populations. In the past decade, advances in integrated population models (IPMs) have allowed these data to be combined with other data sources (e.g., observations of marked individuals).IPMs have allowed researchers to determine the direction and magnitude of a species' population trajectory and to test underlying mechanisms. For many species, life-history characteristics (e.g., low site-fidelity), low abundance and/or low detection probability make it difficult to collect sufficient data; thus, IPMs for these species are difficult to employ. We used count data from eBird to estimate population trends for one such species, the tricolored blackbird (Agelaius tricolor). We combined estimates of relative abundance with banding and nesting data. Our joint estimation of demographic rates allowed us to evaluate their individual contributions to the population growth rate. We suggest that investments in increasing reproductive success and recruitment are the most likely conservation strategies to increase the population. The extensive survey efforts of citizen scientists aided the employment of IPMs to inform conservation efforts.

Recent trends in Tricolored Blackbird colony size: analysis of the 2008 through 2017 Triennial Statewide Surveys

“…However, the 5% annual decrease in colony size observed during this study was statistically indistinguishable from the 6% decline in overall abundance recently reported from a study (Robinson et al 2018) that analyzed completely different count data from the eBird program (Sullivan et al 2014). The similarity in annual declines across the two studies suggest that tricolored blackbird population decline is occurring through a decline in colony size, possibly more so than a decline in colony number.…”

“…The similarity in annual declines across the two studies suggest that tricolored blackbird population decline is occurring through a decline in colony size, possibly more so than a decline in colony number. The integrated population model analysis by Robinson et al (2018) combined eBird relative abundance data with independent data on productivity and survival. Correlations between population growth rates and vital rates suggested that population growth was especially sensitive to adult female survival and productivity (Robinson et al 2018).…”

Disentangling data discrepancies with integrated population models

“…Such methods have only recently been introduced in ecology and present computational and analytical challenges (e.g., accounting for sampling biases from volunteer‐collected data; Sullivan et al. ), but offer potentially powerful avenues for incorporating “big data”, such as opportunistic species sightings by the public (e.g., eBird), into integrated modeling frameworks (Robinson et al., in press ). Similarly, eliciting expert opinion can be a useful approach in cases where deficient data prohibit the ability to build reliable statistical models.…”

Comparing abundance distributions and range maps in spatial conservation planning for migratory species

“…, Robinson et al. ). Weekly estimates of relative abundance enable prioritization to explicitly consider the dynamic nature of species’ populations and to identify sites with high proportions of species’ populations.…”

“…To fill this gap, we use weekly estimates of shorebird relative abundance (hereafter, abundance) across the Americas, derived from eBird data (Sullivan et al 2014). eBird data include curated and reviewed contributions from citizen scientists and some professional surveys, and have been used to derive species' distributions and inform conservation action , Reynolds et al 2017, Sullivan et al 2017, Robinson et al 2018. Weekly estimates of relative abundance enable prioritization to explicitly consider the dynamic nature of species' populations and to identify sites with high proportions of species' populations.…”