USGS ScienceSearch

USGS · 70277722

Society’s struggle with unwanted species: What centuries of history reveal about species bounty programs

Abstract

Species bounty programs, much like bounty hunters charged to bring fugitives to justice, enlist the public to locate and remove unwanted species through financial incentives. With the goal of reducing population sizes, these programs address perceived ecological and economic damage caused by target species. In this study, we provide the first global assessment of species bounty programs, drawing on evidence from both historical and contemporary efforts across diverse regions and cultural contexts over the past eight centuries. We uncovered a long history of bounty programs involving at least 283 species—mammals, birds, fish, plants, reptiles, mollusks, insects, amphibians, and crustaceans—across 449 programs in 60 countries. Using this collective knowledge, we offer five perspectives on species bounty programs. First, bounty programs are launched for a variety of reasons, including economic (livestock, crops, fisheries, infrastructure), ecological (species, ecosystems), and social (human health) considerations related to unwanted species. Second, bounty programs vary in their design and implementation, ranging from well-planned operations with clear management and conservation objectives to ad hoc operations with limited articulation and investigation of project outcomes. Third, evidence points to unintended consequences, in which bounty programs result in the incidental removal of non-target species or in effects that may inadvertently benefit target species. Fourth, while not always the case, fraudulent activities have been reported, compromising the management outcomes of some programs. Fifth, public perception of bounty programs is highly dynamic and ensuring program engagement remains a persistent challenge. By reviewing the scattered narratives of past and present bounty programs globally, this review seeks to inform the evolving role of this management strategy.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Julian D. Olden, Jessica O. Diallo, Rachel M. Fricke, Emily Jameson, Rachelle Carina Johnson, Rebekah R. Stiling, Brielle K. Thompson. 2026-05-30. Society’s struggle with unwanted species: What centuries of history reveal about species bounty programs. https://doi.org/10.1038/s44185-026-00132-x

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

Practitioners perceptions of biodiversity-relevant criteria for solar suitability analyses in the United States

Acceleration of large-scale solar energy deployment can pose competition for land with biodiversity conservation areas. Solar suitability analyses (SSAs) help identify low-conflict zones for solar development, yet limited work defines which biodiversity-relevant criteria (BRCs) are essential for SSAs or whether supporting data are available. We convened a United States-based Delphi panel of practitioners with expertise in biodiversity and renewable energy to identify BRCs that are essential across SSAs (‘core’) and data- or scale-limited (‘peripheral’). Practitioners identified 16 core and 13 peripheral BRCs. Core criteria primarily aligned with regulatory frameworks, while peripheral BRCs reflected context-dependent ecological attributes lacking consistent and scalable data. Open-access data were available for 14 core criteria across 10 databases. Our assessment of US-based SSAs revealed that 10 included core BRCs. Our findings indicate a need for improved access to fine-scale biodiversity data and coordination with agencies to improve SSAs.

npj Biodiversity

Amphibian richness, rarity, threats, and conservation prospects across the U.S. National Park System

We assessed amphibian diversity, rarity, and threats across the National Park System (U.S.A.), which covers 3.5% of the country and 12% of federal lands. At least 230 of 354 (65%) amphibian species documented in the country occur on National Park Service lands. Of species in parks, 17% are at-risk globally and 20% are uncategorized, reflecting still-widespread data deficiencies. National parks in the Northwest and Northeast had the steepest species‒area relationships. Non-native crayfishes and amphibians occur within 50 km of 60% and 25% of parks, respectively, illustrating the broad threat of non-native predators. Projected mid-century (2040–2069) changes in climatic water deficit, based on 25 climate futures, produced an expected 34% increase in dryness across all national parks in the conterminous U.S.A. Our analyses highlight the extent and regional differences in current and future threats and reveal gaps in species protection, but also reveal opportunities for targeted expansion and active management.

npj Biodiversity