Endangered species conservation strategies, population recovery, and long-term survival of threatened wildlife species: A synthesis of evidence and practice

Abstract

The global loss of biodiversity has accelerated to the point that monitored vertebrate populations declined by an estimated 73% between 1970 and 2020, and more than 48,000 species are currently classified as threatened with extinction on the IUCN Red List. Against this backdrop, this review synthesises peer-reviewed and institutional evidence on the principal strategies used to conserve endangered species and recover threatened populations, and evaluates the conditions under which these strategies contribute to long-term species survival. Using a structured narrative-review approach, the paper examines six interacting strategy domains: protected areas and landscape connectivity; conservation genetics and genetic rescue; ex situ breeding, reintroduction, and biotechnological tools; community-based protection and enforcement against illegal wildlife trade; climate-change adaptation planning; and international policy and finance mechanisms. Evidence indicates that no single intervention reliably prevents extinction in isolation; rather, documented recoveries — illustrated here through the Iberian lynx, whose population grew from 62 mature individuals in 2001 to more than 2,000 individuals by 2024 — consistently combine habitat restoration, demographic and genetic management, and socially embedded protection. The review also identifies persistent constraints, including an estimated annual global biodiversity finance gap of approximately US$700 billion, incomplete evidence on corridor and reintroduction efficacy, and the likelihood that current extinction-risk models underestimate climate-driven range loss. The review concludes that durable species recovery depends on integrated, adequately funded, and locally legitimate conservation portfolios rather than isolated technical fixes.