Bayesian Meta-Analysis of Conservation Interventions for Endangered Species with Sparse Outcome Data

Abstract

The major objective of the paper was to perform Bayesian meta-analysis to assess the effectiveness of
conservation interventions targeting endangered species, given situations with sparse data.
Particularly, the study aimed at comparing the efficacy of some conservation measures, including
habitat restoration, species translocation, captive breeding, and anti-poaching measures, to serve as an
improvement of species survival and conservation of biodiversity. Web of Science, Scopus, and
Google Scholar were selected as systematic literature search platforms that identified the studies that
reported quantitative results of conservation interventions. A total of 20 empirical studies and 112
effect sizes were selected after inspection of the studies and the application of the inclusion criteria.
A Bayesian random-effects meta-analysis was used in the study to bring prior knowledge to explain
the uncertainties and heterogeneity across the studies. This model enabled the synthesis of thin data
that generated more valid estimates of intervention effectiveness. The Bayesian meta-analysis showed
that the overall effect size is moderate, 0.48 (95% credible interval: 0.26-0.69), which shows that
conservation intervention tends to enhance population-level response. The positive impacts were the
most consistent with habitat restoration and measures based on policies, with means of 0.62 and 0.55,
respectively. Interventions, such as species translocation and captive breeding, however, had a more
mixed result. The heterogeneity was significant (I² = 64.3%, τ² = 0.21), and the effectiveness of the
interventions depends on the situation. This experiment is quite convincing about the fact that
conservation interventions have a beneficial effect on the recovery of endangered species, and the
efficacy of the intervention is dependent on the kind of intervention and the situation. The findings
have demonstrated the importance of the adaptive and context-sensitive approaches, as well as the
need to conduct additional research to be able to maximize practices like species translocation and
captive breeding. Continued investment in habitat restoration and policy-based measures is essential
for long-term biodiversity conservation.