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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. En Cuba, la región del Golfo de Batabanó es la más importante zona de pesca de langosta debido a que de ella se extrae anualmente alrededor del 70% de la captura nacional. Con el objetivo de determinar variaciones espacio-temporales en la condición nutricional (K) de langostas Panulirus argus del Golfo de Batabanó, Cuba, se calculó dicha condición mediante una relación pesolargo (K=Pt/Lt), para lo que se utilizaron ejemplares de cuatro zonas (uno, dos, cuatro y cinco) del este del golfo, capturados en los años 1981 y 2010. Se encontró que en todos los casos analizados la condición nutricional fue significativamente mayor en machos que en hembras. Se detectaron variaciones significativas entre zonas en 1981 y 2010. También entre años el estado nutricional de las langostas presenta variaciones significativas, de manera que en 1981 (2.34±0.84g/mm) fue mayor que en 2010 (1.96±0.49g/mm). Tanto las variaciones interzonales como las interanuales parecen estar relacionadas con variaciones reportadas en el tipo de fondo y la cobertura vegetal. Variaciones estacionales en la abundancia y distribución de organismos bentónicos que constituyen alimento para las langostas también podrían estar influyendo. Las diferencias entre sexos en cambio, se suponen consecuencia de la metodología utilizada y del dimorfismo sexual característico de esta especie, por cuanto otros métodos de estimación de K que no involucran mediciones morfométricas, no detectan estas diferencias.

Resumen Con el objetivo de identificar los organismos que conforman la dieta natural de la langosta Panulirus argus y determinar diferencias entre sexos en cuanto a la importancia de cada presa, se analizaron 30 estómagos con contenido (16 hembras y 14 machos), extraídos de langostas capturadas al Este del golfo de Batabanó. Se identificaron 15 entidades alimentarias (12 en las hembras y 14 en los machos). Las entidades preferenciales coincidieron en ambos sexos, aunque en los machos se incluyeron además los foraminíferos y los restos minerales. Los crustáceos fueron el único grupo de importancia alta y son las presas mayormente consumidas (G=62.3% en las hembras y G=40% en los machos). Se determinó la presencia de opérculos de Lobatus gigas, Turbo castanea, Fasciolaria tulipa, Nassarius antillarum,Cerithium spy Tegula fasciata, que fue la que mostró mayor presión de depredación (2.25 en las hembras y 2.14 en los machos). Esta especie junto a Cerithium sp. fueron las que presentaron mayor abundancia numérica (60.5% y 33.9% respectivamente). La prueba U de Mann-Whitney arrojó que entre sexos no existen diferencias en el peso del contenido estomacal. La similaridad entre las dietas fue de 96.75% y se compone fundamentalmente de crustáceos y moluscos. AbstractSex differences in the composition of the natural diet of Panulirus argus (Decapoda: Palinuridae) in the eastern of the Gulf of Batabano, Cuba. The spiny lobster Panulirus argus is one of the most valuable fishery resources in the Caribbean Sea. This is the only species of lobster that has commercial importance in Cuba. This study was aimed to identify the organisms that conform the natural diet for both sexes of P. argus and to determine the importance of each prey in the diet of each sex. A total of 30 stomachs of commercial lobsters (≥ 76mm of carapace length) was analyzed. The identified content was grouping by items and classified for species if it was possible. The total weight of each item was determined and the gravimetric method was applied to estimate the relative weight of the principal diet components. The most frequently consumed prey was also determined. Items with high, middle or low importance were established by the relative importance index (IIR). Similarities between both sexes diet were estimated by similarity index (ISe). Stomachs were extracted of lobsters captured in a fishing zones from eastern of the gulf of Batabano. The predation pressure (P) on the mollusks species found in the stomach content was calculated based on the respective opercula. It was possible to identified 15 feeding entities (12 in females and 14 in the males) being the preferences: crustacean rests (100%), shell rests (80%), vegetable rests (70%), opercula (63%) and mineral rests (53%). Those preference entities were the same between sexes although in the males the foraminifera and the mineral rest were included. The IIR showed crustaceans as a single group of high importance. The gravimetric analysis showed crustaceans as the most consumed prey (62.3% in females and 40% in males). The opercula of Lobatus gigas, Turbo castanea, Fasciolaria tulipa, Nassarius antillarum, Cerithium sp and Tegula fasciata were found. Tegula fasciata showed the highest predation pressure (2.25 in females and 2.14 in males) and together Cerithium sp. they were the most abundant species (60.5% and 33.9% respectively). Respect to the weight of stomach contents the Mann-Whitney test showed no significant difference between females and males. The diet of both sexes of P. argus in the assessed area was similar (ISe=96.75%) and it was constituted mainly of crustaceans and mollusks.