Small size today, aquarium dumping tomorrow: sales of juvenile non-native large fish as an important threat in Brazil

Abstract

Informal sales of large-bodied non-native aquarium fishes (known as "tankbusters") is increasing among Brazilian hobbyists. In this study, we surveyed this non-regulated trade on Facebook ® from May 2012 to September 2016, systematically collecting information about the fishes available for trading: species, family, common/scientific names, native range, juvenile length, behavior, number of specimens available in five geographical regions from Brazil. We also assessed the invasion risk of the most frequently sold species using the Fish Invasiveness Screening Test (FIST). We found 93 taxa belonging to 35 families. Cichlidae was the dominant family, and most species were native to South America. All species are sold at very small sizes (< 10.0 cm), and most display aggressive behavior. The hybrid Amphilophus trimaculatus × Amphilophus citrinellus, Astronotus ocellatus, Uaru amphiacanthoides, Osteoglossum bicirrhosum, Cichla piquiti, Pangasianodon hypophthalmus, Datnioides microlepis and Cichla kelberi were the main species available. The southeast region showed the greatest trading activity. Based on biological traits, the FIST indicated that Arapaima gigas, C. kelberi and C. temensis are high-risk species in terms of biological invasions via aquarium dumping. We suggest management strategies such as trade regulations, monitoring, euthanasia and educational programs to prevent further introductions via aquarium dumping.Keywords: Aquarium releases, Aquarium trade, Biological invasions, Invasiveness, Propagule pressure.A venda de juvenis de peixes não-nativos de grandes dimensões, chamados de "peixes jumbo", está aumentando entre aquaristas no Brasil. Neste trabalho, pesquisou-se este comércio informal pelo Facebook ® de maio/2012 a setembro/2016, coletando-se informações sobre espécies, família, nomes vulgares/científicos, origem, tamanho juvenil, comportamento e número/frequência de exemplares disponíveis nas cinco regiões geográficas do Brasil. Também avaliou-se o risco de invasão das espécies mais vendidas usando o protocolo Fish Invasiveness Screening Test (FIST). Foram encontradas 93 espécies pertencentes a 35 famílias. Cichlidae foi a família dominante, e a maioria das espécies é nativa da América do Sul. Todas as espécies foram vendidas como juvenis (< 10.0 cm), e a maioria exibe comportamento agressivo. O híbrido Amphilophus trimaculatus × Amphilophus citrinellus, Astronotus ocellatus, Uaru amphiacanthoides, Osteoglossum bicirrhosum, Cichla piquiti, Pangasianodon hypophthalmus, Datnioides microlepis e Cichla kelberi foram as espécies mais comercializadas. A região sudeste apresentou a maior porcentagem de vendas, e o FIST mostrou que Arapaima gigas, C. kelberi e C. temensis foram consideradas de alto risco para desencadear invasões biológicas mediadas por descarte de aquários. Recomendações como a regulação do comércio, monitoramento, sacrifício das espécies e campanhas educacionais para os aquaristas são sugeridas para evitar futuras introduções de peixes via descarte de aquários. Palavras-chave:Comércio o...

Emerging threats and persistent conservation challenges for freshwater biodiversity

“…The array of mechanisms for making transactions is diverse, including standard retail websites, auction sites, local businesses, wanted ads, online portals and chat fora (NISC, ). Social media is further complicating the landscape, particularly through informal retail (Magalhães et al ., ). Web crawlers have been used to monitor the Internet for the sale of illegal animals and plants (Sonricker Hansen et al ., ); similarly, enforcement authorities could use Internet tools such as machine‐learning algorithms to identify sellers of prohibited invasive species (Di Minin et al ., ).…”

The Art of Aquarium Keeping Communicates Science and Conservation

“…This includes diseases associated with aquatic organisms (Whittington and Chong, 2007;Lawson et al, 2015), invasive species release (Padilla and Williams, 2004;Delaney et al, 2008;Howeth et al, 2016;Bandaranayake and Chandrasekara, 2017;Magalhães et al, 2017;Selwyn et al, 2017;Tuckett et al, 2017) and use for popular aquarium species for breeding and scientific research (Hoff, 1996;Moe, 2003;Moorhead and Zeng, 2010;Olivotto et al, 2011;Domínguez and Botella, 2014;Tehrani et al, 2014). Another, far less common focus for research includes the human dimensions of the aquarium trade and hobby.…”

Species composition and invasion risks of alien ornamental freshwater fishes from pet stores in Klang Valley, Malaysia

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