Daily Cleaning Activity and Diversity of Clients of the Barber Goby, Elacatinus figaro, on Rocky Reefs in Southeastern Brazil

Gobies of the genus Elacatinus are regarded as the most specialised cleaner fishes in the western tropical Atlantic, yet there are no studies on these cleaners in the southern portion of West Atlantic. We studied the diversity of clients and the daily cleaning activity of the barber goby, Elacatinus figaro, on rocky reefs in southeastern Brazil (23–24°S). A total of 34 fish client species in 16 families were recorded over 484 cleaning events. The most frequent clients were damselfishes, Pomacentridae (37.9% of cleaning events) and grunts, Haemulidae (16.9%). Planktivores were the most frequently attended trophic category, and two species in that category accounted for about a half (44%) of the total cleaning events. Size of clients ranged 4.5–55cm and most individuals were medium-sized (12–30cm); as the barber goby ranged 2–4.5cm, clients were 1.5 to 15 times larger than the cleaner was. Cleaning activity started at dawn and ended shortly before nightfall, the highest frequency of interactions occurring at early morning (nocturnal clients) and mid-afternoon (diurnal clients). By midday the frequency of cleaning events decreased and their duration increased. A total of 109±3 cleaning events and 30±1min of cleaning activity were estimated per cleaning station per day, both figures low when compared to those recorded for cleaner fishes in tropical areas of the western Atlantic and Indo-Pacific.     

Association of Large Juvenile Red Drum, Sciaenops ocellatus, with an Estuarine Creek on the Atlantic Coast of Florida

Seasonal abundance, size distribution, year-class presence, residence duration, and migrational patterns of red drum, Sciaenops ocellatus, in an estuarine marsh creek in the northern Indian River Lagoon, Florida, were investigated during a study in which gill net samples were collected monthly from August 1991 to March 1996. A total of 282 large juvenile red drum were collected, of which 161 were tagged and released and 68 were sacrificed for age determination. Although red drum were collected in the creek throughout the year, abundance levels were negatively correlated with water temperatures and reached maximum levels during the winter months. Significant correlations between fish abundance and salinity or dissolved oxygen levels were not detected. The majority (90%) of the fish collected were large juveniles (260–450mm standard length) that were estimated to be from 10 to 26 months old. The oldest red drum we examined from the creek was estimated to be 37 months old. Tag-recapture data indicated that some fish repeatedly used or were associated with the creek for periods of up to 18 months after release. Estuarine creeks in this region provide exploitable habitat for large juvenile red drum (相似文献   

Bathytyphlops sewelli (Pisces: Chlorophthalmidae) a senior synonym of B. azorensis, from the eastern North Atlantic with notes on its biology

Evidence provided by six specimens of abyssal Bathytyphlops collected in the eastern North Atlantic indicates the conspecificity of the Atlantic B. azorensis with the Indian Ocean B. sewelli. The data also clarify the distinction between B. sewelli and its congener, B. marionae. The benthic habit of B. sewelli is confirmed. Its reproductive biology is examined and the hermaphroditic pattern substantiated. The species is evidently a multiple spawner with a fecundity of around 6000 eggs. Observations in support of the probable epipelagic larval development of B. sewelli are dicussed. Stomach and intestinal contents analysis suggests that this species feeds largely on benthopelagic crustaceans. Digenetic trematode parasites were found in the digestive tracts of three specimens.