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The spatiotemporal variations of megazoobenthos on soft bottoms in Buena Vista (BV) and San Juan de Los Remedios (SJR) bays, Cuba, were assessed to infer the effects of the elimination of bottom trawl fisheries and the creation of protected areas. Data were collected at 11 sites in 2010-2013 (six routines and five exploratories) and 11 sites in 2014-2017 (four routines and seven exploratories). Samples were obtained by dredging. Mollusks were the most frequent and diverse group, followed by echinoderms and crustaceans. Total density (7.60 ind m-2) and biomass (15.82 g m-2) of the benthic community were highest in SJR in 2015. Although total biomass was lower at BV (t = 2.21; P = 0.032), there were no significant differences in density between bays (t = 0.77; P = 0.444). The site with a lower total density and biomass was located at BV. There were no differences between years except at one site, where density increased between 2010 and 2017. Total density and biomass were not significantly different inside and outside of the Zone Under Special Regime of Use and Protection (ZUSRUP) at the beginning of the sampled period. However, both density and biomass were significantly higher within the ZUSRUP at the end (2017), which suggests this protected area's effectivity. The progressive increase in density at one site and greater density and biomass values at SJR, where bottom trawl fisheries were more intensive, suggest eliminating bottom trawl nets may have contributed to the benthic fauna recovery. [ABSTRACT FROM AUTHOR]

Introduction: Benthos is an efficient indicator of environmental disturbances, biodiversity and trophic dynamics. In Cuba, benthic mollusks have been reported as the main food for the lobster Panulirus argus. Objectives: To estimate spatiotemporal variations in the soft-bottom benthic community of the Gulf of Batabanó, and to infer, with emphasis on mollusks, the effect of such variations on the availability of food for spiny lobsters. Methods: A historical analysis of the variations in the density and biomass of megazoobenthos (organisms = 4 mm) and particularly of megazoobenthic mollusks was carried out, taking as a reference the studies published in 1990 (with samples from 1983) and recent data (2007-2018) recorded on site using comparable methodologies based on sediment drags. Abundance was given as density (ind/m2) and biomass in g/m2. Results: It was found that both the density and the biomass were significantly higher at the end of the last century and show a tendency to gradually decrease towards recent times. Regarding the values reported in 1983, the density of organisms showed a decrease of 73%, however, the biomass experienced an even greater decrease (86%). The areas with the highest density and biomass, both benthos and mollusks, have varied from 1983 and are currently located towards the center of the gulf. Despite this, bivalves continue to be better represented than gastropods. In general, mollusks showed a significant decrease (55% and 88% respectively). Conclusions: The deterioration of the benthic community in the fishing areas of the Gulf of Batabanó was corroborated and it was demonstrated, based on megazoobenthos, that malacofauna can be used as a reliable indicator of the general parameters of the softbottom benthic community. The availability of food for lobsters have decreased 55.6% compared to 1983. This could help to explain the current changes in the abundance, distribution and nutritional condition of lobsters, which could also be related to the recent megazoobenthos variations. [ABSTRACT FROM AUTHOR]

Commercial sponge catches in Cuba show decreases that require maintaining a precautionary approach and ensuring strict compliance with regulatory measures. This study aims to determine variations in abundance, size and quality of commercial sponges in the Gulf of Batabanó, during the 2015-2019 period, and to propose fishing management measures that favor this resource sustainability. Sponges density was estimated in 2x100 m (200 m2) transects. The fishing potential, expressed in metric tons, was calculated from the average density of individuals. The catch quota was calculated based on 15% of the fishing potential. The most represented species were Spongia obscura and S. barbara. The densities found (between 0.01 and 0.03 ind/m2) were low, but correspond to those reported at the end of the last decade, which corroborates the stabilization of catches (average annual quota of 18.7 metric tons) and demonstrates the effectiveness of the current fishing management. However, the density and size show a tendency to decrease between 2015 and 2019. This, together with the decrease in the abundance of Hippospongia lachne, the presence of totally or partially dead sponges and the poor quality of some specimens, suggests the deterioration of the fishing stock. Based on the habitat affectations reported for this region, it is recommended to reduce the annual quota to 10% of the fishing potential, not to extract specimens smaller than 15 cm in diameter and to implement sponge aquaculture again. [ABSTRACT FROM AUTHOR]

The results of the monitoring Reef Check in the coral reef of Rincón de Guanabo protected area during 2000, 2001, 2002 are presented. This survey was carried out to evaluate the coral reef's health, to obtain the basic scientific information for establishing the management plans and to involve the community volunteers in the conservation activities. Fixed stations in 3 and 10 m deep were settled down. Besides the Reef Check monitoring, in the 2002 a 1 m² frame was used so as to analyze the coral species composition and the abundance of sponges and gorgonians. Alive coral cover was superior to 20% in the crest and in the front reef but didn't show variations in the 3 years. Twenty five species of scleractinian corals were identified, and the most abundant were Agaricia agaricites, Porites astreoides, Siderastraea siderea y Montastraea annularis. Coral density was 13.8 col./m², and higher than gorgonians and sponges density. The low density of Diadema urchin and the almost total absence of commercial fish was significant. The results indicated that the coral reef of Rincón de Guanabo is in good health condition, however, there are serious impacts by over fishing that can bear future ecological dysfunctions. Because of this, it is necessary to continue with Reef Check monitoring that will give reliable scientific information to prevent coral reef destruction and will involve local community to the conservation process. [ABSTRACT FROM AUTHOR]

The effect of pollution on coral recruitment has been insufficiently studied. This research deals with coral recruitment in coastal areas and aimed to determine the variations of density and dominant species of corals recruits in sites at different distances from pollution sources. The composition and structure of stony coral (scleractinian and milleporids) recruit associations were characterized in the fringing reef of Western Havana, Cuba. This reef is influenced by urban pollution from the Almendares River and a sewage outlet located at its mouth. Four sites were sampled on the upper fore reef escarpment at 10m deep every three months between July 2007 and May 2008. A 25cm side quadrat was used to determine the density and taxonomic composition of recruits smaller than 3cm in diameter. Sampling units were placed following a random-systematic pattern. The mean density of recruits was determined both at assemble and species level. Bifactoral ANOVA tests were applied to compare mean densities at both sampling sites and dates. Student-Newman-Keuls test was applied to compare pairs of means. Cluster and nMDS analyses were applied to evaluate between site similarities. The predominant species was Siderastrea siderea followed by S. radians and Porites astreoides. Recruit densities were similar among La Puntilla, Calle 16 and Acuario sites. Lower densities were always found in Malecón. Significant differences in mean stony recruit densities were found both between sites and sampling dates. The statistic analysis did not show significant spatial-temporal interactions. Malecón, the most polluted site, showed the lowest recruit density and the greater presence of species considered as indicators of organic pollution, sedimentation and abrasion. The density of recruit species was higher in October 2007 and lower in May 2008, and it was apparently influenced by reproduction and cold front seasons, respectively. The higher dominance and abundance of S. siderea, S. radians and P. astreoides recruits were apparently due to their high reproductive potential and resistance to disturbances. The identity of dominant species was apparently related to distance from major pollution sources. We highly recommended the replication of this research in other areas of the greater Caribbean region to test the generality of present results and to compare among areas. Future research should take into account the influence of other environmental factors, along with an appraisal of recruit species tolerance to these factors, to better ponder the effect of urban pollution on recruitment. Areas with well assessed pollution regimes are recommended for research. [ABSTRACT FROM AUTHOR]