Colonization record of Isognomon bicolor (Mollusca: Bivalvia) on pipeline monobuoys in the Brazilian south coast

Abstract

Background: The introduction of alien species in a system affecting native species due to competition for food and space. The purse oyster Isognomon bicolor (Bivalvia, Pteriidae), a potential exotic invader, presents gaps in its distribution and ecology knowledge in Brazilian coast. For this reason, our objective was to investigate the occurrence of this oyster on pipeline monobuoys in Rio Grande do Sul, southern Brazil. Specimens were collected monthly during surveys carried out from March 2010 to June 2011 at the Tramandaí Beach, along two pipeline monobuoys, MN-601 and MN-602, randomly from the depths of three and 22 m. Results: We found I. bicolor dwelling on artificial hard substrates present in the Rio Grande do Sul coast, Brazil. This Caribbean bivalve was accidentally introduced to the Brazilian coast by ballast water from ships and, until now; it had not been recorded on the coast of Rio Grande do Sul state, which is under subtropical conditions. Conclusions: The occurrence of I. bicolor in the faunistic surveys accomplished in the Rio Grande do Sul coast represents the first documented record for this species in this region. As this species is a potential exotic invader, with a high dispersal capacity, control measures must be employed to prevent its spread.

What determines sclerobiont colonization on marine mollusk shells?

“…However, there is still no consensus on the main factors that can affect invertebrate colonization on biological substrates such as shells, carapaces, and bones. However, the surface texture has frequently been cited [ 25 – 31 ] together with biological factors, such as competition by recourses [ 32 , 33 ], conspecific presence [ 34 , 35 ], and ecological inter-specific interactions [ 11 , 36 ], to induce or repulse settlement. Experimental arrays conducted on non-biological hard substrates such as steel and concrete have demonstrated that invertebrate settlement might be positively [ 37 – 39 ] or negatively [ 39 – 41 ] influenced by bacterial biofilm.…”

Caracterização Da Macrofauna De Substratos Consolidados Do Litoral Norte Do Rio Grande Do Sul, Brasil

“…CARACTERIZAÇÃO DA MACROFAUNA DE SUBSTRATOS CONSOLIDADOS DO LITORAL NORTE DO RIO GRANDE DO SUL, BRASIL Tabela II -Espécies observadas por Rios et al (1979) Quanto ao bivalve I. bicolor, Agostini & Ozorio (2016) destacam que se trata de registro novo, o qual amplia a distribuição desta espécie exótica no litoral brasileiro. Segundo as autoras, a presença deste molusco nas monoboias de oleodutos de Tramandaí se deve a dispersão por água de lastro devido ao fluxo constante de navios no local.…”