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Diferentes métricas de biodiversidad se deben explorar para evaluar de manera más eficiente los cambios observados en las comunidades. Sin embargo, el desempeño de distintas métricas de biodiversidad no ha sido explorado en el golfo de Batabanó, lo que puede dificultar la selección de índices adecuados para el monitoreo ambiental. Para solventar esta problemática seis métricas de biodiversidad (riqueza de especies, equidad de Pielou, diversidad de Shannon, diversidad taxonómica, distintividad taxonómica promedio y variación en la distintividad taxonómica) fueron comparadas para determinar su congruencia y respuestas ante variables abióticas (salinidad, temperatura, turbidez, profundidad) y factores (zonas y años). Los resultados obtenidos por correlaciones entre las métricas y sus respuestas a las variables abióticas y factores analizados mostraron complementariedad entre la riqueza de especies, equidad de Pielou, diversidad de Shannon, distintividad taxonómica promedio y variación en la distintividad taxonómica, no siendo así para la diversidad taxonómica. Según los resultados de este trabajo, se sugiere el uso de la riqueza de especies y las métricas de distintividad taxonómica ∆+ y Λ+ para evaluar la calidad ambiental del golfo de Batabanó. Además se deben evaluar sus desempeños en otros grupos de organismos.

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.

Resumen: El golfo de Batabanó (GB), es la región de la plataforma marina cubana de mayor extensión e importancia pesquera. Afectaciones al hábitat de especies marinas han sido señaladas como consecuencia de factores naturales y antrópicos. El objetivo fue determinar variaciones espacio-temporales significativas en la hidrología del GB en diferentes periodos y situaciones ambientales. Para ello se analizó la variabilidad de la lluvia y la temperatura del aire en 1975-1995 y 1996-2015 periodos de baja y alta actividad ciclónica, las características termohalinas del GB anterior (1959-1970) y posterior (2006-2016) al represamiento fluvial, y el efecto de dos huracanes casi simultaneaos en 2008 (“Gustav” e “Ike”). Diferencias significativas en la variabilidad interanual de parámetros meteorológicos entre el norte y el sur del GB respondieron a características locales, y ocurrieron cambios en la distribución de los meses de máximas precipitaciones. El represamiento fluvial, sumado a déficits de precipitación en primavera, verano e invierno, provocaron aumentos termohalinos en 2006-2016, con incremento de 0,7 °C en la temperatura del agua y de 2,3 en la salinidad promedio del GB, respecto a 1959-1970. La salinidad mostró una ampliación en la distribución de valores hipersalinos, y media > 36 en meses de altas precipitaciones, con promedio general de 35,4 en 1959-1970 y 37,7 en 2006-2016, esto sugiere que el represamiento ha sido un factor principal en las variaciones de salinidad. El impacto termohalino en el GB de dos huracanes en 2008, se restableció en corto plazo, con mayor inercia en la turbidez.

Resumen Introducción: En el hábitat natural, el estado nutricional insatisfactorio de un número elevado de ejemplares es expresión de la influencia de factores desfavorables. Objetivo: Determinar variaciones espacio-temporales en el estado nutricional de langostas Panulirus argus, relacionarlas con variaciones reportadas en la comunidad bentónica y demostrar, mediante la aplicación de indicadores analíticos y morfométricos, que la variación de factores ambientales afecta a ambos grupos de índices; y que no todos los índices de condición nutricional evidencian por igual el impacto generalizado del proceso de deterioro ambiental en este golfo. Métodos: Las langostas se capturaron en seis áreas de pesca. La condición nutricional se estimó mediante tres índices no destructivos, poco costosos y de fácil y rápida aplicación (extensivos): índice de refracción de la hemolinfa (IRH), relación peso total / largo total = Klt, y factor de condición (FCA). Las variaciones a largo plazo (60 años) se determinaron mediante índices morfométricos (Klt y FCA). Se analizaron datos de los períodos 1963-1964 (N = 29 001), 1983-1993 (N = 3 123) y 2011-2017 (N = 3 600), separándolos en épocas de Lluvia y Seca. Resultados: En todos los períodos la condición nutricional varió significativamente entre áreas, pero sin similitudes entre períodos. Esto indica que los factores que impactan en el estado nutricional tienen una influencia estocástica más característica de factores ambientales. Aunque los tres índices fueron menores en 2017, sólo IRH disminuyó gradualmente entre 2011 y 2017, lo que sugiere que este índice, y los morfométricos, expresan diferente información. Todas las correlaciones fueron estadísticamente significativas, los coeficientes más altos se establecieron entre los índices morfométricos. El peso total y el Klt no mostraron diferencias entre Seca y Lluvia. Sin embargo, IRH y FCA resultaron mayores en Seca, hecho que se constató para cada sexo. FCA y Klt no presentaron diferencias entre el período 1963-1964 y el período 1983-1993, pero aumentaron (P < 0.05) en el período 2011-2017, lo que, dado el carácter morfométrico de estos índices, se atribuye a la presencia de langostas de mayor peso en las áreas de pesca. Conclusiones: Los menores valores en 2017 y la tendencia gradual al decrecimiento de IRH, corroboran el carácter generalizado del deterioro ambiental en el golfo de Batabanó, lo cual no fue igualmente expresado por los tres índices. Abstract Introduction: Nutritional condition indices are morphophysiological estimators that quantify the nutritional status of organisms. In the natural habitat, unsatisfactory nutritional stage of numerous individuals is an expression of unfavorable factors. Objectives: Determine spatio-temporal variations in the nutritional condition of lobsters Panulirus argus, relate them to variations reported in the benthic community, and to demonstrate, through the application of analytical and morphometric indices, that variations of environmental factors affects both groups of indices due to its potential magnitude and its generalized nature. Methods: Lobsters were captured at six sites. Nutritional condition was estimated by three non-destructive, inexpensive and quick indices also easy to apply, which it means extensive indices: blood refractive index (BRI), relationship between total weight and total length (K), and condition factor (CFA). Because there are no historical records of BRI, long-term variations (60 years) were determined using morphometric indices (Klt and CFA). Data from the periods 1963-1964 (N = 29 001), 1983-1993 (N = 3 123) and 2011-2017 (N = 3 600) were analyzed, separating them in the rainy and dry seasons. Results: In all the periods the nutritional condition varied significantly between sites, but without similarities between periods. Despite this, it increased progressively in three sites. This indicates that factors impacting nutritional condition have a stochastic influence that is constantly changing, which is more characteristic of environmental factors than anthropogenic factors. Although the three indices showed a lower nutritional condition in 2017, only BRI gradually decreased between 2011 (16.6) and 2017 (14.2), which suggests that this index, and the morphometrics (Klt and CFA), express different information. All correlations were statistically significant but greatest coefficients were established between morphometric indices. The total weight and the Klt index did not show differences between rainy and dry seasons. However, BRI and CFA were statistically greater in dry season, a fact that was found for each sex. Both CFA and Klt decreased slightly (P > 0.05) between the first (1963-1964) and the second (1983-1993) period and then increased (P < 0.05) in the current period (2011-2017). Because they both are morphometric indices, this was attributed to the presence of greater weight lobsters. Conclusions: The lowest values in 2017 and gradually decreasing trend in BRI, corroborate the generalized nature of the environmental deterioration in the Gulf of Batabanó, but this was not equally expressed by the three indices.

The main fishing enterprise located in the province of Pinar del Rio, Cuba, markets oyster meat packed in brine bags of 460 g. The oysters come from natural bank fisheries (mangrove and bottom oyster), and from farms (mangrove oyster). Although the capture during 2009 – 2013 showed an increasing trend (50 to > 80 t), the oyster meat yields recorded values below (3.3 – 3.9 %), the acceptable minimums (4.9 %); in addition, a decrease in meat weight was observed between the packaging and commercialization, impacting productivity. The objectives of the study were the assessment of oyster exploitation based on the meat yield, and to assess the meat loss in the final packed product. A monthly and annual yield variation analysis and their relationship between fishery type and oyster size was performed. Meanwhile, the loss of meat was analyzed by different treatments of oyster / brine proportions. Significant differences (p < 0.05) of meat yield (%) by oyster species and size with a better performance in the farmed oysters were observed. The traditional proportion of packing for commercialization (meat / brine, 391 g / 69 g = 460 g), influenced the weight-loss of meat by leakage of interstitial fluid. After the treatments with different proportions of meat / brine, the proportion 1:1 showed the least loss of meat weight. The breach of commercial size and the lack of cleanliness of the oysters before the shell removing process, impacted the meat yield analysis during 2009-2013

Background. In the marine environment of San Cruz Island, no published references exist regarding the ecology of soft-bottom mollusks. Thus, it is important to carry out research that broadens and deepens the knowledge of this marine area and contributes to proposals of management methods and alternatives for the sustainable use of insular marine resources. Goals. This study seeks to characterize the community composition and structure of soft-bottom mollusks of the infralitoral zone of Santa Cruz Island, and describe some of the characteristics associated with their habitat. Methods. During August 2010, 32 samples were collected: 16 were biological samples and 16 were sediment samples. The composition, abundance, and diversity of the malacological community were analyzed using ecological indexes. Results. 695 individuals were recorded and grouped in two classes: Gastropoda with 446 organisms (5 orders, 11 families, and 19 species); the most abundant species was Siphonaria maura (18%); the class Bivalvia included 249 organisms (8 orders, 14 families, and 25 species); the most abundant species was Tellina eburnea (10%). The Gastropoda class were more abundant than the Bivalvia, i.e., 64.17% and 35% respectively. The species with major abundances and relative frequencies were the gastropods Siphonaria maura (18%) and the bivalve Septifer seteki (69%). Four trophic categories were identified: filterers (73%), herbivores (20%), carnivores (5%), and ectoparasites, the latter of which were the rarest group (2 %). Conclusions. At this site, the specific richness (44 taxa) was lower compared to other sites from different latitudes of the western Gulf of California, likely derived from the higher energy environment of the study area that allowed only juvenile mollusks and micromollusks to be collected.

The influence of three potential anthropogenic stressful factors (coastal pollution from the mainland, the causeway Caibarien–Santa Maria and fishing with bottom-trawling nets) on the condition of seagrasses was assessed at 12 sites in two bays of Sabana–Camaguey​ archipelago, between 2010 and 2013. As for indicators of the condition of the seagrass ecosystem, the structure of the macrophyte community, marine angiosperm’s shoot density, and shoot length of marine angiosperms were analyzed. Abiotic variables as depth, turbidity, temperature, pH, dissolved oxygen, oxygen saturation, and chemical oxygen demand of seawater, were evaluated. The relationships of the three potential anthropogenic stressful factors and the abiotic factors (predictor variables) with the biological response variables were analyzed. Seagrass meadows in better condition, with higher values of cover and density of Thalassia testudinum, and lower values of depth, turbidity, salinity, chemical oxygen demand, were found at sites out of the bays and furthermost from the causeway and mainland. Areas without vegetation or with lower values of cover and density of T. testudinum, and higher cover of macroalgae and pioneer species of marine angiosperms as Syringodium filiforme and Halodule wrightii, were found in both bays. Turbidity and depth were the abiotic factors with the stronger negative influence on the structure of the seagrass community. Chemical oxygen demand and salinity also showed negative influences. Coastal pollution seems to be the anthropogenic factor that most influences the condition of seagrasses. No recovery of seagrasses was observed in areas where bottom-trawling fisheries had ceased. Distance to the causeway was not correlated with the condition of seagrass, but the potential for a negative influence on circulation persists. Seagrasses in the studied bays remain affected by the above-mentioned predictor abiotic factors, whose effects may be reinforced by the three anthropogenic stressful factors, acting synergistically with the bays’ oceanographic characteristics.

La distinción taxonómica es una medida de diversidad que presenta una serie de ventajas que dan connotación relevante a la ecología teórica y aplicada. La utilidad de este tipo de medida como otro método para evaluar la biodiversidad de los ecosistemas marinos bentónicos de fondos blandos del Golfo de Batabanó (Cuba) se comprobó mediante el uso de los índices de distinción taxonómica promedio (Delta+) y la variación en la distinción taxonómica (Lambda+) de las comunidades de moluscos. Para este propósito, se utilizaron los inventarios de especies de moluscos bentónicos de fondos blandos obtenidos en el periodo 1981-1985 y en los años 2004 y 2007. Ambos listados de especies fueron analizados y comparados a escala espacial y temporal. La composición taxonómica entre el periodo y años estudiados se conformó de 3 clases, 20 órdenes, 60 familias, 137 géneros y 182 especies, observándose, excepto en el nivel de clase, una disminución no significativa de esta composición en 2004 y 2007. A escala espacial se detectó una disminución significativa en la riqueza taxonómica en el 2004. No se detectaron diferencias significativas en Delta+ y Lambda+ a escala temporal, pero si a escala espacial, hecho que se puede atribuir al efecto combinado del incremento de las actividades antropogénicas en la región con los efectos inducidos por los huracanes. Estos resultados sugieren que el par de índices Delta+ y Lambda+ son buenos descriptores de la biodiversidad de las comunidades de moluscos bentónicos de fondos blandos del Golfo de Batabanó. Taxonomic distinction is a measure of diversity that has a number of advantages that provides relevant connotation to theoretical and applied ecology. The usefulness of this type of measure as an alternative method for assessing the biodiversity of soft-bottom benthic marine ecosystems was tested using the indices of average taxonomic distinctness (Delta+) and variation in taxonomic distinctness (Lambda+) for mollusk communities of the Gulf of Batabanó (Cuba). For this purpose, inventories of soft bottom benthic mollusk species obtained in the period 1981-1985 and the years 2004/2007 were used. Both species lists were analyzed and compared at spatial and temporal scales. The taxonomic composition, between the period 1981-1985 and years 2004 and 2007, consisted of 3 classes, 20 orders, 60 families, 137 genera and 182 species observed. With the exception of the class level, a non-significant decrease of this composition in 2004 and 2007 was detected. At a spatial scale, a significant decrease in the taxonomic richness was observed in 2004. Significant differences were not detected in Delta+ and Lambda+ to time scale, but at spatial scale, results revealed significant differences that could be attributed to the combined effect of increased anthropogenic activities in the region with hurricane induced effects. These results suggest that the pair of indices, Delta+ and Lambda+, are good descriptors of the biodiversity of soft-bottom benthic mollusk communities in the Gulf of Batabanó.

Nutritional condition can affect survival and growth rate of crustaceans, and this is mostly affected by habitat conditions. This study describes the space-temporary nutritional changes in this commercially important species. With this aim, the variations in the nutritional condition (K) of lobsters from four zones (1, 2, 4 and 5) in the Gulf of Batabano, Cuba, were determined. For this, the weight/length ratio (K=Pt/Lt) was calculated using animals captured in 1981 and 2010. The nutritional condition between areas and sexes, and years and sexes, was contrasted by a bifactorial ANOVA, and the overall length and weight of lobsters were compared using a t-Test for independent samples and unifactorial ANOVA. It was found that the nutritional condition was significantly greater in males than in females. In addition, significant variations between zones were detected for both years. Nutritional condition of lobsters from Zone five was the highest for 1981, while it was Zone two for 2010. Lobsters nutritional state showed significant variations between years, being greater in 1981 (2.34±0.84g/mm) than in 2010 (1.96±0.49g/mm). The inter-zones variations as well as the inter-annual ones seem to be related to the reported variations of the bottom type and the vegetation cover. Seasonal variations in the abundance and distribution of benthic organisms, that constitute food for lobsters, could also be influencing. The differences between sexes, however, were assumed as a consequence of the methodology used and the sexual dimorphism of the species. Due to other K estimation methods, that do not include morphometric measurements, these differences were not detected. We suggested that the P. argus nutritional condition is a good estimator of the habitat condition. Besides, according to the applied K estimation methodology, it was found that different groups of lobsters that have resemblant nutritional condition, did not necessarily observe similarities in the overall mean length or weight, so they could exist under different habitat conditions.

Nutritional condition can affect survival and growth rate of crustaceans, and this is mostly affected by habitat conditions. This study describes the space-temporary nutritional changes in this commercially important species. With this aim, the variations in the nutritional condition (K) of lobsters from four zones (1, 2, 4 and 5) in the Gulf of Batabanó, Cuba, were determined. For this, the weight/length ratio (K=Pt/Lt) was calculated using animals captured in 1981 and 2010. The nutritional condition between areas and sexes, and years and sexes, was contrasted by a bifactorial ANOVA, and the overall length and weight of lobsters were compared using a t-Test for independent samples and unifactorial ANOVA. It was found that the nutritional condition was significantly greater in males than in females. In addition, significant variations between zones were detected for both years. Nutritional condition of lobsters from Zone five was the highest for 1981, while it was Zone two for 2010. Lobsters nutritional state showed significant variations between years, being greater in 1981 (2.34 +/- 0.84g/mm) than in 2010 (1.96 +/- 0.49g/mm). The inter-zones variations as well as the inter-annual ones seem to be related to the reported variations of the bottom type and the vegetation cover. Seasonal variations in the abundance and distribution of benthic organisms, that constitute food for lobsters, could also be influencing. The differences between sexes, however, were assumed as a consequence of the methodology used and the sexual dimorphism of the species. Due to other K estimation methods, that do not include morphometric measurements, these differences were not detected. We suggested that the P. argus nutritional condition is a good estimator of the habitat condition. Besides, according to the applied K estimation methodology, it was found that different groups of lobsters that have resemblant nutritional condition, did not necessarily observe similarities in the overall mean length or weight, so they could exist under different habitat conditions.

"The cyclonic activity within the Gulf of Batabanó has been historically documented and, in the past two decades, it has been possible to observe signals of environmental degradation in its physical and biological state. Yet a study aimed at evaluating the effects of cyclonic activity on the taxonomic diversity of mollusks has not been made. The objective of this study was to evaluate the effects of cyclonic activity during 1981-1985 and 2004-2009 on the taxonomic diversity of soft-bottom mollusks of this region. To measure the cyclonic activity, the Power of Dissipation Index for hurricanes (PDI) was used. The average taxonomic distinctness index (Delta+) and the variation in the taxonomic distinctness (Lambda+) of the inventory of the mollusks species for both periods were used as a measure of taxonomic diversity. We detected high cyclonic activity (HCA) during 2004-2009 and low cyclonic activity (LCA) during 1981-1985. The taxonomic composition during both periods was made up of 3 classes, 20 orders, 68 families, 155 genus, and 208 species. Significant differences in the taxonomic composition between the two periods were detected, due principally to the loss of genus and species. The taxonomic distinctness index reveals significant changes of the taxonomic structure of mollusks during 2004-2009, which is related to a rise in cyclonic activity. These results suggest that the taxonomic diversity of mollusks was less complex during 2004-2009 than during 1981-1985."