Population Dynamics and Secondary Production of the Invasive Bivalve Mytilopsis leucophaeata (Bivalvia, Dreissenidae) in Lagoa Rodrigo De Freitas, Rio De Janeiro, Brazil

Do feeding responses of a non-native bivalve outperform the native one in a coastal lagoon? A possible explanation for the invasion success of the dark false mussel Mytilopsis leucophaeata

“…However, the invasive dark false mussel is the most abundant species of epibenthic macrofauna in Rodrigo de Freitas Lagoon, reaching densities between 60,000 to 120,000 ind. m −2 ( Maia-Neto, Caetano & Cardoso, 2020 ), that are much higher than B. darwinianus in the same lagoon ( Rodrigues et al, 2021 ). Environmental modifications induced by the dense aggregates and biomass dominance of M. leucophaeata may favor this non-native species over the native bivalve B. darwinianus .…”

“…Before the assays, bivalve shells were cleaned and measured (in length) using a digital calliper with 0.05 mm precision. Bivalves with total length varying from 15 to 20 mm ( = 0.23 ± 0.06 g wet weight) were sorted to be used in the assays, since this size range did not differ in tissue mass and comprises the most representative cohorts of the bivalves found in Rodrigo de Freitas Lagoon ( Maia-Neto, Caetano & Cardoso, 2020 ; Rodrigues et al, 2021 ). Subsequently, individuals of M. leucophaeata ( n = 75) and B. darwinianus ( n = 30) were acclimated under starvation for 48 h in glass aquariums (40 L) with artificial brackish water at controlled conditions of temperature (21.5 °C) and salinity (14 ppt), considering mean values of environmental conditions found at lagoon.…”

“…In Rodrigo de Freitas Lagoon, an urban coastal system in Southeastern Brazil (Rio de Janeiro city), the dark false mussel M. leucophaeata was first recorded in 2014 ( Rizzo et al, 2014 ). Currently this species is the most abundant epibenthic macrofauna in the lagoon, being widely distributed throughout its littoral zone ( Maia-Neto, Caetano & Cardoso, 2020 ; Rodrigues et al, 2021 ). The evaluation of historical data of Rodrigo de Freitas Lagoon and results obtained from laboratory experiments evidenced that dark false mussels increased water transparency and reduced the density of fecal bacteria Escherichia coli ( Neves et al, 2020 ).…”

First Record of Microplastic Contamination in the Non-Native Dark False Mussel Mytilopsis leucophaeata (Bivalvia: Dreissenidae) in a Coastal Urban Lagoon

“…Individuals with total shell lengths varying from 10 to 20 mm were sorted to be used in microplastic analysis to avoid an effect on individuals' size. This size range comprises the most representative cohorts of M. leucophaeata in Rodrigo de Freitas Lagoon [15]. The individuals were previously removed from their shells using sterilized stainless-steel forceps, and their soft tissue was wet-weighted (w.w.) using a precision balance (0.0001 g) and then subjected to chemical digestion by adding 50 mL of 10% KOH solution.…”

“…The first record of this non-native species was in 2004 in estuaries of the state of Pernambuco in the Northeast country's region [14] and, after a decade, M. leucophaeata was found in Rodrigo de Freitas Lagoon, Rio de Janeiro city, at the Southeastern region of Brazil [12]. The dark false mussel M. leucophaeata became the most abundant epibenthic macrofauna in the Rodrigo de Freitas Lagoon, being widely distributed throughout its littoral zone [13,15], concurrently with the report of a reduced density of the native bivalve Brachidontes darwinianus (Linnaeus, 1798) in this system [16]. Negative impacts of non-native bivalves on native species are associated with higher rates of seston filtration and food ingestion of the invaders, competition for space with native fouling species, shifts in habitat structure and refuge areas for benthic species, and changes in prey availability for higher trophic levels, altering community structure and food webs [8,13,[16][17][18].…”