Community structure of shallow rocky shore fish in a tropical bay of the southwestern Atlantic

Abstract

Southwestern Atlantic Ocean rocky shores sustain important reef fish communities. However, those communities in tropical regions are not well understood, especially in Brazil. In this present article we assess community parameters of reef fishes such as composition, trophic organization and their relationships with physical and biological factors on four tropical rocky shores in Todos os Santos Bay, southwestern Atlantic. During six months, a total of 80 visual censuses were performed, in which 3,582 fish belonging to 76 species were recorded. Territorial herbivorous fish and turf algae were dominant at all the sites. The spatial variability of fish community structure was related to the benthic cover composition and depth. The high abundance of territorial herbivores and mobile invertebrate feeders could be associated with high levels of turf cover, low wave exposure and shallow waters. Moreover, this fact could be a consequence of the low density of roving herbivores and large carnivores probably due to the pressure of intense fishing activity. Thus complementary studies are needed to evaluate the actual conservation status of these rocky shore reefs, singularly located habitats connecting inner and outer reefs in Todos os Santos Bay.

Network of small no-take marine reserves reveals greater abundance and body size of fisheries target species

“…This is also likely, since territorial herbivores, such as damselfishes ( Stegastes spp. ), are found in complex regions of the reef protecting colonies of the major components of their diet, primarily fast growing red and green filamentous algae [113,114]. As habitat characteristics were more influential in herbivores abundance than protection status, fisheries effects were not evident for these groups, even though some of them are targeted in the region.…”

Network of small no-take marine reserves reveal greater abundance and body size of fisheries target species

“…This is similar with the results for territorial herbivores, in which protection was only important when combined with topographic complexity. This is also likely, since territorial herbivores, such as Stegastes ssp., are found in complex regions of the reef protecting colonies of the major components of their diet, primarily fast growing red and green filamentous algae [100, 101]. As habitat characteristics were more influential in herbivores abundance than protection status, fisheries effects were not evident for these groups, even though some of them are targeted in the region.…”

New non-native ornamental octocorals threatening a South-west Atlantic reef

“…Despite photographic records of Sarcothelia from 2015, previous ecological studies at TSB did not find evidence for the presence of any of the conspicuous, attractive and colourful octocorals cited here (Ferreira et al, 2015b;Barros et al, 2018). Ferreira et al (2015b) provided a detailed benthic community description of the study site showing that turf complex was the dominant functional group at the rocky reefs, reaching a mean coverage of 34.75% ± 15.68. In this study, although turf complex is also an abundant component at RR, Sarcothelia sp.…”

“…This study was conducted in the rocky reefs of Porto da Barra, an area encompassing ∼30,000 m 2 , located at one of the most popular urban beaches of the city of Salvador, Bahia, Brazil (13°0 ′ 14.41 ′′ S 38°32 ′ 2.38 ′′ W) (Figure 1). This area has high biodiversity and receives a large number of bathers and tourists yearround (Ferreira et al, 2015b). The rocky reef environments under study are situated in the entrance of Todos os Santos Bay (TSB) (Figure 1), which is ∼1200 km 2 and contains several important and preserved ecosystems, although some portions of this bay have been historically subjected to environmental impacts, such as eutrophication, pollution and overexploitation of natural resources (Andrade & Hatje, 2009).…”