Journal Article

Effectiveness of Predator Removal for Enhancing Bird Populations

SUTHERLAND, WILLIAM J., SMITH, REBECCA K., PULLIN, ANDREW S., STEWART, GAVIN B.

2010

Overview

Predation pressure on vulnerable bird species has made predator control an important issue for international nature conservation. Predator removal by culling or translocation is controversial, expensive, and time-consuming, and results are often temporary. Thus, it is important to assess its effectiveness from all available evidence. We used explicit systematic review methodology to determine the impact of predator removal on four measurable responses in birds: breeding performance (hatching success and fledging success) and population size (breeding and postbreeding). We used meta-analysis to summarize results from 83 predator removal studies from six continents. We also investigated whether characteristics of the prey, predator species, location, and study methodology explained heterogeneity in effect sizes. Removing predators increased hatching success, fledging success, and breeding populations. Removing all predator species achieved a significantly larger increase in breeding population than removing only a subset. Postbreeding population size was not improved on islands, or overall, but did increase on mainlands. Heterogeneity in effect sizes for the four population parameters was not explained by whether predators were native or introduced; prey were declining, migratory, or game species; or by the study methodology. Effect sizes for fledging success were smaller for ground-nesting birds than those that nest elsewhere, but the difference was not significant. We conclude that current evidence indicates that predator removal is an effective strategy for the conservation of vulnerable bird populations. Nevertheless, the ethical and practical problems associated with predator removal may lead managers to favor alternative, nonlethal solutions. Research is needed to provide and synthesize data to determine whether these are effective management practices for future policies on bird conservation.

• Publisher: Blackwell Publishing Inc,Wiley-Blackwell,Blackwell Publishing Ltd
• Subject: Animal breeding / Animal populations / Animal, plant and microbial ecology / Animals / Applied ecology / Aves / Biological and medical sciences / bird conservation / Bird nesting / Bird populations / Birds / Breeding / conservación basada en evidencias / conservación de aves / Conservation biology / Conservation of Natural Resources / Conservation, protection and management of environment and wildlife / Continents / culling / erradicación de depredadores / ethics / evidence-based conservation / fledglings / Fundamental and applied biological sciences. Psychology / game animals / Habitat conservation / Hatching / hatching success / Heterogeneity / indigenous species / introduced species / Islands / issues and policy / managers / Meta-analysis / meta-análisis / metodología de revisión sistemática / migratory behavior / Migratory species / natural resources conservation / Nature conservation / Nesting / nests / Parks, reserves, wildlife conservation. Endangered species: population survey and restocking / Population Growth / Population number / Population size / Predation / Predator control / predator eradication / Predators / Predatory Behavior / Prey / reproductive performance / selección / systematic review / systematic review methodology / Threatened species / Translocation / Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution / Wildlife conservation / éxito de eclosión