Fish biodiversity and conservation in South America

Area of Science:

• Ichthyology and Conservation Biology
• Biodiversity Science

Background:

• South America harbors the planet's most diverse freshwater and marine fish faunas, with over 9100 estimated species.
• This exceptional biodiversity evolved over 100 million years, influenced by Gondwanan origins and Cenozoic climate shifts.
• The continent's aquatic systems are categorized into 13 major basin complexes and coastal drainages.

Purpose of the Study:

• To comprehensively describe the fish diversity, endemism, and knowledge status of South American freshwater and marine ecosystems.
• To assess the conservation status and threats facing these unique aquatic faunas.

Main Methods:

• Compilation and synthesis of existing data on fish species richness and distribution across South American basin complexes.
• Analysis of marine fish diversity in coastal and oceanic habitats.
• Evaluation of anthropogenic threats, including habitat alteration and overfishing, impacting fish populations.

Main Results:

• South America's freshwater fish fauna is estimated to reach 8000-9000 species, with over 5160 currently known.
• Approximately 4000 marine fish species inhabit South American waters.
• 4-10% of South American fish species face extinction risk, primarily due to habitat loss and degradation, with marine species being particularly threatened.

Conclusions:

• While South American freshwater fish conservation status is relatively better than in other global regions, marine fish face significant threats.
• Conserving South America's rich aquatic biodiversity requires urgent attention and action amidst rapid anthropogenic changes.
• Effective conservation strategies are crucial for policy makers and conservationists to protect these invaluable ecosystems.