Geographic expansion of the invasive mud sleeper Butis koilomatodon (Perciformes: Eleotridae) in the western Atlantic Ocean.

The Indo-Pacific mud sleeper Butis koilomatodon (Eleotridae) is recorded for the first time in the south-western Atlantic Ocean, based on 23 specimens caught at seven localities along the northern, north-eastern, eastern and south-eastern Brazilian coast. The occurrence of males and females in different ontogenetic stages indicates that this exotic mud sleeper breeds there. This invasive species has the potential to compete for food and microhabitat with several native gobies and an endemic blenny that dwell in estuaries and mangroves, besides preying on native fishes and crustaceans.

Meals for two: foraging activity of the butterflyfish Chaetodon striatus (Perciformes) in southeast Brazil.

The banded butterflyfish (Chaetodon striatus) from the tropical and subtropical western Atlantic is a territorial, diurnal forager on benthic invertebrates. It is usually seen moving singly or in pairs, a few meters above the sea floor. We studied the foraging activity of C. striatus on rocky reefs in southeastern Brazil. This fish spent about 11 h and 30 min per day on feeding activities, and preferred colonies of non-scleratinian anthozoans over sandy and rocky substrata while foraging. The lowest feeding rates were recorded in the early morning and late afternoon, but we found no further differences between feeding rates throughout the day. We also found no differences between the feeding rates of paired and single individuals.

Meals for two: foraging activity of the butterflyfish Chaetodon Striatus (perciformes) in southeast Brazil

O peixe-borboleta (Chaetodon striatus) do Atlântico ocidental tropical e subtropical é uma espécie territorial, diurna e que forrageia sobre invertebrados bentônicos, sendo geralmente encontrada aos pares ou solitária, nadando poucos metros acima do substrato. Estudamos a atividade de forrageamento dessa espécie em recifes rochosos no sudeste brasileiro. O peixe-borboleta despende cerca de 11 h e 30 min em atividades alimentares por dia e prefere colônias de antozoários a substratos arenosos e rochosos para o forrageamento. As menores taxas de forrageamento foram registradas ao amanhecer e ao entardecer, não sendo encontradas outras diferenças nessa freqüência ao longo do dia. Não foram encontradas diferenças entre a freqüência alimentar de indivíduos aos pares e solitários.

Chirocentrodon bleekerianus (Teleostei: Clupeiformes: Pristigasteridae), a small predaceous herring with folded and distinctively oriented prey in stomach.

Predaceous fish-eating species of the order Clupeiformes have a large mouth with well-developed teeth, and reach the greatest sizes within their families (up to 90 cm). We found that the pristigasterid Chirocentrodon bleekerianus, a small clupeiform (about 10 cm) from the tropical SW Atlantic, is able to prey on proportionally large clupeoid fishes and caridean shrimps. Fish preys are folded in the stomach of this herring, their heads and tails pointing toward the predator's head. This distinctive orientation of fish prey is also recorded for some small to medium-sized, fish-eating species of the tropical freshwater order Characiformes with canine-like teeth similar to those found in C. bleekerianus.

Chirocentrodon bleekerianus (Teleostei: Clupeiformes: Pristigasteridae), a small predaceous herring with folded and distinctively oriented prey in stomach

Dentre os Clupeiformes, as espécies piscívoras apresentam boca grande, com dentes bem desenvolvidos, e alcançam os maiores portes dentro de suas famílias (até 90 cm). Registramos que o pristigasterídeo Chirocentrodon bleekerianus, um clupeiforme de pequeno porte (cerca de 10 cm) do Atlântico Sul Ocidental, apresa peixes e camarões proporcionalmente grandes. Os peixes ingeridos ficam dobrados no estômago dessa sardinha, com suas cabeças e caudas em direção à cabeça do predador. Essa orientação distinta de presas também ocorre em algumas espécies piscívoras de Characiformes de pequeno a médio porte, que apresentam dentes caninos similares aos encontrados em C. bleekerianus.

Feeding biology of a guild of benthivorous fishes in a sandy shore on south-eastern Brazilian coast

The feeding biology of eight species of benthivorous fishes was studied in a sandy shore at Anchieta Island, south-eastern Brazilian coast. The fishes fed mainly on Amphipoda and Mysidacea crustaceans. The diet of the most abundant species, the drum Umbrina coroides, was analyzed in three standard length classes (20-55, 56-90 and 91-135 mm). This sciaenid showed an ontogenetic diet shift from Mysidacea to Amphipoda. The feeding behaviour of the sciaenid U. coroides and the gerreid Eucinostomus gula was recorded while snorkeling. During their foraging both species uncovered small organisms buried in the sand. Notwithstanding general similarities in diet, U. coroides and E. gula presented differences in feeding behaviour and morphology. Two carangid species of the genus Trachinotus differed in diet composition and consumed a larger array of food items than the remaining fish species. Differences in diet and feeding activity between the remaining benthivorous species were noted. These differences possibly reduce overlap in resource use and favour the coexistence of guilds of benthivorous fishes on sandy shores

Feeding biology of a guild of benthivorous fishes in a sandy shore on south-eastern Brazilian coast.

The feeding biology of eight species of benthivorous fishes was studied in a sandy shore at Anchieta Island, south-eastern Brazilian coast. The fishes fed mainly on Amphipoda and Mysidacea crustaceans. The diet of the most abundant species, the drum Umbrina coroides, was analyzed in three standard length classes (20-55, 56-90 and 91-135 mm). This sciaenid showed an ontogenetic diet shift from Mysidacea to Amphipoda. The feeding behaviour of the sciaenid U. coroides and the gerreid Eucinostomus gula was recorded while snorkeling. During their foraging both species uncovered small organisms buried in the sand. Notwithstanding general similarities in diet, U. coroides and E. gula presented differences in feeding behaviour and morphology. Two carangid species of the genus Trachinotus differed in diet composition and consumed a larger array of food items than the remaining fish species. Differences in diet and feeding activity between the remaining benthivorous species were noted. These differences possibly reduce overlap in resource use and favour the coexistence of guilds of benthivorous fishes on sandy shores.