The impact of the aquarium hobby on endangered species is nuanced and varies significantly with species and collection practices. For species commonly found in the trade and lacking effective regulation, overharvesting from the wild has demonstrably contributed to population declines. However, for many endangered species, particularly those with limited commercial appeal or challenging husbandry requirements, the direct pressure from the aquarium trade is minimal compared to factors such as habitat destruction, pollution, and invasive species.
Captive breeding initiatives within the hobby can mitigate some risks by providing alternative sources for popular species, thereby lessening the incentive to collect from wild populations. Nevertheless, for certain narrowly endemic species or those with very specific ecological needs, even low levels of removal can be harmful, especially when layered onto existing environmental threats. The relative threat posed by the aquarium trade should therefore be assessed on a case-by-case basis, informed by population data and collection practices for each species.
I agree, it really depends on the species and where the fish come from. Captive breeding seems like a good way to reduce pressure on wild populations, as long as it’s done responsibly.