Ricardo J. Miranda

New occurrences of the nonindigenous orange cup corals Tubastraea coccinea and T. tagusensis (Scleractinia: Dendrophylliidae) in Southwestern Atlantic

The genus Tubastraea , with natural occurrence in the Pacific Ocean, was reported for the first time in Brazil along the coast of Rio de Janeiro. Since then it has also been reported in other sites along the south and southeast Brazilian coasts in oil platforms and rocky shores. We describe for the first time the occurrence of Tubastraea tagusensis and T. coccinea in the Northeastern coast of Brazil. The corals were found in the state of Bahia, sitting on shipwrecks, marina jetties as well as occupying space on a coral reef.

The invasion of the azooxanthellate coral Tubastraea (Scleractinia: Dendrophylliidae) throughout the world: history, pathways and vectors

In this review, we describe the history, pathways and vectors of the biological invasion of the azooxanthellate coral Tubastraea (Scleractinia: Dendrophylliidae) throughout the world. In order to do so we consulted previous reports in the literature and also compiled new unpublished information on the distribution of the three species of Tubastraea which have been reported as non indigenous species, both within their native and non-native ranges and also on vectors, and where cryptogenic. We combine these data with historical aspects of marine vectors in order to get insights into how Tubastraea species have successfully spread around the world, established and invaded and where future studies would be best focused. T. coccinea and T. tagusensis are recognized as being highly invasive and are causing significant environmental, economic, and social impacts requiring management actions. The third species, T. micranthus so far only reported outside its native range on oil platforms, may have similar potential for negative impact. The vectors of introduction of Tubastraea may have changed throughout history and the biological invasion of these invasive corals may reflect changing practices, demands and legislation in shipping activities over the years. Today it is clear that these corals are fouling organisms strongly associated with oil and gas platforms worldwide which are thus primary vectors for new introductions.

New records of the alien cup-corals (Tubastraea spp.) within estuarine and reef systems in Todos os Santos Bay, Southwestern Atlantic

BackgroundThe alien cup-coral Tubastraea spp. has been increasingly reported in the Southwestern Atlantic since the 1980s. More recently it was observed on the East coast of Brazil, the area with the highest biodiversity in the Southwest Atlantic. In the present study, we report the actual distribution of Tubastraea tagusensis and Tubastraea coccinea around Todos os Santos Bay (TSB), an important system in the Southwest Atlantic coast.ResultsWe mapped the geographic expansion of Tubastraea tagusensis and Tubastraea coccinea at 11 sites in estuarine and 2 in reef systems at TSB.ConclusionsThe findings from our study will contribute to monitor alien expansion and implement management actions to control these invasions on the Brazilian coast.

Benthic Habitats in Todos os Santos Bay

Benthos are organisms, animals or plants, that live in direct relationship with the bottom. Benthic organisms have great ecological and economic importance. Several marine and coastal ecosystems such as mangroves, coral reefs, salt marshes and estuaries have an important benthic component, supporting a great biological diversity and providing a lot of services (e.g. refuge, spawning sites, feeding sites, breeding sites and coastline protection). Chemical and physical variables can strongly influence benthic organisms because it controls a great part of the environmental conditions in which a species can live. Furthermore, changes in the composition and or on the abundance of benthic species may indicate human impacts. Here we present the main characteristics of important benthic habitats of the Todos os Santos Bay (TSB), contextualizes some results of the TSB Project and discuss impacts on mangroves and coral reefs on different spatial scales. Despite the impacts, many of the benthic habitats in the TSB are still in a good conservation status and fully developing important ecological, economic and social functions. It is strongly suggested that a precise survey to map all benthic habitats in the TSB must be done and also the maintenance and creation of long term ecological monitoring programs.

Do invasive corals alter coral reef processes? An empirical approach evaluating reef fish trophic interactions

Understanding how invasive species affect key ecological interactions and ecosystem processes is imperative for the management of invasions. We evaluated the effects of invasive corals (Tubastraea spp.) on fish trophic interactions in an Atlantic coral reef. Remote underwater video cameras were used to examine fish foraging activity (bite rates and food preferences) on invasive cover levels. Using a model selection approach, we found that fish feeding rates declined with increased invasive cover. For Roving Herbivores (RH) and Sessile Invertivores (SI), an abrupt reduction of fish feeding rates corresponded with higher invasive cover, while feeding rates of Territorial Herbivores (TH) and Mobile Invertivores (MI) decreased linearly with cover increase. Additionally, some fish trophic groups, such as RH, SI and Omnivores (OM), had lower densities in reef sections with high invasive cover. These findings demonstrate that invasive corals negatively impact fish-benthic interactions, and could potentially alter existing trophic relationships in reef ecosystems.

Cryptobenthic fish as clients of french angelfish Pomacanthus paru (Pomacanthidae) during cleaning behaviour

The French angelfish Pomacanthus paru (Pomacanthidae) is recognised as an important cleaner in tropical reef environments, yet its clients remain relatively undescribed in the literature. Here, we report observations of their cleaning behaviour when interacting with different species of cryptobenthic fish clients. The study was conducted in Bahia state, northeast Brazil. In this region, French angelfish were seen cleaning four different species of cryptobenthic species, respectively, Coryphopterus glaucofraenum, Scorpaena plumieri, Labrisomus cricota, and Scartella cristata. These records show the broad spectra of clients that cleaners interact with in coral reef systems, as well as give important insights into the poorly known cryptobenthic fishes habits and ecology.

Spongivory by Fishes on Southwestern Atlantic Coral Reefs: No Evidence of Top-Down Control on Sponge Assemblages

Predator-prey dynamics can affect assemblage structure and ecosystem processes representing a central theory in ecology. In coral reef ecosystems, recent evidences have suggested that sponge assemblages in regions with high diversity, like the Caribbean, are controlled by reef fishes (i.e. top-down control); however, this has been poorly studied in low diversity coral reefs. This study investigated the influence of fish predators on sponge assemblage structure in South Atlantic coral reefs, systems with high endemism and relatively low hermatypic coral diversity. We investigates (i) whether sponge cover is negatively correlated to spongivorous fish density, (ii) potential spongivory effects on competitive interactions between sponges and hermatypic corals and (iii) foraging preferences of spongivorous fishes. Benthic cover and spongivorous fish density were assessed by photo samplingt and visual census, respectively. We did not observe a negative correlation of the total density of sponge fish with total sponge cover . However, a significant negative correlation between density of fish species Pomacanthus arcuatus and cover of sponge species Scopalina ruetzleri was found. Spongivorous fish consumed preferentially the sponges Desmapsamma anchorata, Niphates erecta, Aplysina cauliformis and Scopalina ruetzleri, the first two species considered palatable and the second two with chemically defense mechanism. An increase to angelfish density was not related with the number of coral-sponge encounters. Thus, the effects of spongivorous fishes on sponges cover and competitive interactions with hermatypic corals is weaker in Southwestern Atlantic than previously reported in Caribbean coral reefs. We discuss how local human impacts (e.g. fishing and nutrients input) can influence the observed patterns.

New insights into whale shark Rhincodon typus diet in Brazil: an observation of ram filter-feeding on crab larvae and analysis of stomach contents from the first stranding in Bahia state

We describe the first record of a whale shark, Rhincodon typus, feeding in Brazilian coastal waters, and the first stranding record in the state of Bahia, Northeast Brazil. In April 2008, an individual of R. typus was observed surface feeding on Dromiidae crab larvae in the continental shelf off the coast of Bahia, near a gas platform. Other fishes were observed foraging in association with the whale shark. We also document the first stranding of R. typus on the coast of Bahia in October 2013. Biometric data confirmed that the stranded whale shark was a juvenile. Stomach content analysis revealed the ingestion of Geryonidae crab larvae. Plastic debris were also found in the gastric lumen of the stranded juvenile whale shark, and we speculate that it could have been a contributing factor to the stranding, and subsequent death of the whale shark. Crab larvae were observed in both of our records and likely to consist as relevant prey items for R. typus in Brazilian continental shelf. Our study provided a contribution on the diet and feeding behaviour of whale sharks in tropical oligotrophic waters and highlights the risks of marine pollution for the species conservation.