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Lobster fishing is the most economically attractive activity in Northeast Brazil. In this work, the catch variations of the lobsters Panulirus meripurpuratus (red spiny), Panulirus laevicauda (smoothtail) and Scyllarides brasiliensis (Brazilian slipper lobster) in Pernambuco in the years 1999 to 2006 were evaluated to determine trends in monthly production rates and the relationship between the catches made in the closed period and during open season. Seasonal catches were studied from exponential models and correlation analysis. The exponential models were significant and showed determination coefficients above 0.65 for red spiny in all years and for smoothtail starting in 2002, and they described the decline in catches from the beginning to the end of the season. The biomass of the smoothtail showed a more pronounced decline compared to the red lobster, possibly because the capture coefficient would be higher. As for the Brazilian slipper lobster, the models had values of determination coefficients always below 0.40. The correlation between legal and illegal capture was significant only for smoothtail and showed a positive trend. The initial magnitude of the catch for red spiny below 25 tonnes at the beginning of the fishing season can be an alarming indication, whereas for smoothtail, this value can be 10 tonnes. Studies with surplus production models are necessary to better assess stocks and verify the hypothesis that smoothtail would have a higher capture coefficient than that of red spiny., A extração de lagostas é considerada a atividade pesqueira mais atrativa economicamente na região Nordeste do Brasil. Neste trabalho, foram avaliadas as variações das capturas das lagostas Panulirus meripurpuratus (lagosta vermelha), Panulirus laevicauda (lagosta verde) e Scyllarides brasiliensis (lagosta sapata) no estado de Pernambuco, nos anos de 1999 a 2006, com intuito de verificar tendências nas produções mensais e a relação entre as capturas realizadas nos meses de defeso e na temporada de pesca. As capturas por temporada foram estudadas a partir de modelos exponenciais e análises de correlações. Modelos exponenciais foram significativos com coeficientes de determinação acima de 0,65 para lagosta vermelha em todos os anos e para a lagosta verde a partir de 2002, e descreveram os decaimentos das capturas do início até o final da temporada. A biomassa da lagosta verde mostrou um decaimento mais acentuado do que a da vermelha, possivelmente porque o coeficiente de capturabilidade seria maior. Já para a lagosta sapata, os modelos tiveram valores dos coeficientes de determinação sempre inferiores a 0,40. A correlação entre a captura legal e ilegal foi significativa apenas para a lagosta verde e apresentou tendência positiva. A magnitude inicial das capturas para a lagosta vermelha com valores abaixo de 25 toneladas no início da temporada de pesca pode ser um indício alarmante, enquanto para lagosta verde, esse valor pode ser de 10 toneladas. Estudos com modelos de excedente de produção são necessários para melhor avaliar os estoques e verificar a hipótese de que a lagosta verde teria um coeficiente de capturabilidade maior que o da lagosta vermelha.

It has been speculated that Sagmariasus verreauxi (Eastern Rock Lobster) is an important predator of the barrens-forming urchin species Centrostephanus rodgersii (Long-Spined Urchin) and Heliocidaris erythrogramma (Short-Spined Urchin). Both urchin species can cause extreme habitat modification when occurring at high densities and this is considered a problem within NSW marine parks. Elsewhere, lobster predation on urchin by similar species Jasus edwardsii (Southern Rock Lobster) is considered key in controlling urchin populations, but whether S. verreauxi has a similar trophic impact is unknown. In this study, I for the first time investigate the likely value of S. verreauxi as an urchin control agent. I use a holistic approach that investigates lobster diet and feeding behaviour by using dissections and feeding trials and investigate urchin predation rates inside and outside of No-Take Sanctuary Zones (SZ’s) using diver surveys and urchin tethering experiments. I also use external tagging and passive-receiver acoustic telemetry to observe whether large and small lobster use and remain resident within sanctuary zones. Additionally, I have collated 125 observations on lobster size (carapace length, mm) between all experimental locations to test whether larger S. verreauxi are associated with SZ’s. My dissections and Gut Contents Analysis (GCA) of 118 S. verreauxi freshly collected and donated frozen from areas within the Sydney, Shoalhaven, Illawarra and Central Coast regions of NSW imply that lobsters eat urchins less frequently than expected and did not support the prediction that large lobsters eat more urchins. I found urchin material in < 20% of the 118 lobsters dissected and did not find urchin in 96 individuals. I found H. erythrogramma exclusively in small-sized lobsters and C. rodgersii in lobster of various sizes, though at a lower frequency. Using open water mesocosms I presented two urchins of one species to 14 S. verreauxi during nocturnal feeding trial

It has been speculated that Sagmariasus verreauxi (Eastern Rock Lobster) is an important predator of the barrens-forming urchin species Centrostephanus rodgersii (Long-Spined Urchin) and Heliocidaris erythrogramma (Short-Spined Urchin). Both urchin species can cause extreme habitat modification when occurring at high densities and this is considered a problem within NSW marine parks. Elsewhere, lobster predation on urchin by similar species Jasus edwardsii (Southern Rock Lobster) is considered key in controlling urchin populations, but whether S. verreauxi has a similar trophic impact is unknown. In this study, I for the first time investigate the likely value of S. verreauxi as an urchin control agent. I use a holistic approach that investigates lobster diet and feeding behaviour by using dissections and feeding trials and investigate urchin predation rates inside and outside of No-Take Sanctuary Zones (SZ’s) using diver surveys and urchin tethering experiments. I also use external tagging and passive-receiver acoustic telemetry to observe whether large and small lobster use and remain resident within sanctuary zones. Additionally, I have collated 125 observations on lobster size (carapace length, mm) between all experimental locations to test whether larger S. verreauxi are associated with SZ’s. My dissections and Gut Contents Analysis (GCA) of 118 S. verreauxi freshly collected and donated frozen from areas within the Sydney, Shoalhaven, Illawarra and Central Coast regions of NSW imply that lobsters eat urchins less frequently than expected and did not support the prediction that large lobsters eat more urchins. I found urchin material in < 20% of the 118 lobsters dissected and did not find urchin in 96 individuals. I found H. erythrogramma exclusively in small-sized lobsters and C. rodgersii in lobster of various sizes, though at a lower frequency. Using open water mesocosms I presented two urchins of one species to 14 S. verreauxi during nocturnal feeding trial

It has been speculated that Sagmariasus verreauxi (Eastern Rock Lobster) is an important predator of the barrens-forming urchin species Centrostephanus rodgersii (Long-Spined Urchin) and Heliocidaris erythrogramma (Short-Spined Urchin). Both urchin species can cause extreme habitat modification when occurring at high densities and this is considered a problem within NSW marine parks. Elsewhere, lobster predation on urchin by similar species Jasus edwardsii (Southern Rock Lobster) is considered key in controlling urchin populations, but whether S. verreauxi has a similar trophic impact is unknown. In this study, I for the first time investigate the likely value of S. verreauxi as an urchin control agent. I use a holistic approach that investigates lobster diet and feeding behaviour by using dissections and feeding trials and investigate urchin predation rates inside and outside of No-Take Sanctuary Zones (SZ’s) using diver surveys and urchin tethering experiments. I also use external tagging and passive-receiver acoustic telemetry to observe whether large and small lobster use and remain resident within sanctuary zones. Additionally, I have collated 125 observations on lobster size (carapace length, mm) between all experimental locations to test whether larger S. verreauxi are associated with SZ’s. My dissections and Gut Contents Analysis (GCA) of 118 S. verreauxi freshly collected and donated frozen from areas within the Sydney, Shoalhaven, Illawarra and Central Coast regions of NSW imply that lobsters eat urchins less frequently than expected and did not support the prediction that large lobsters eat more urchins. I found urchin material in < 20% of the 118 lobsters dissected and did not find urchin in 96 individuals. I found H. erythrogramma exclusively in small-sized lobsters and C. rodgersii in lobster of various sizes, though at a lower frequency. Using open water mesocosms I presented two urchins of one species to 14 S. verreauxi during nocturnal feeding trial

It has been speculated that Sagmariasus verreauxi (Eastern Rock Lobster) is an important predator of the barrens-forming urchin species Centrostephanus rodgersii (Long-Spined Urchin) and Heliocidaris erythrogramma (Short-Spined Urchin). Both urchin species can cause extreme habitat modification when occurring at high densities and this is considered a problem within NSW marine parks. Elsewhere, lobster predation on urchin by similar species Jasus edwardsii (Southern Rock Lobster) is considered key in controlling urchin populations, but whether S. verreauxi has a similar trophic impact is unknown. In this study, I for the first time investigate the likely value of S. verreauxi as an urchin control agent. I use a holistic approach that investigates lobster diet and feeding behaviour by using dissections and feeding trials and investigate urchin predation rates inside and outside of No-Take Sanctuary Zones (SZ’s) using diver surveys and urchin tethering experiments. I also use external tagging and passive-receiver acoustic telemetry to observe whether large and small lobster use and remain resident within sanctuary zones. Additionally, I have collated 125 observations on lobster size (carapace length, mm) between all experimental locations to test whether larger S. verreauxi are associated with SZ’s. My dissections and Gut Contents Analysis (GCA) of 118 S. verreauxi freshly collected and donated frozen from areas within the Sydney, Shoalhaven, Illawarra and Central Coast regions of NSW imply that lobsters eat urchins less frequently than expected and did not support the prediction that large lobsters eat more urchins. I found urchin material in < 20% of the 118 lobsters dissected and did not find urchin in 96 individuals. I found H. erythrogramma exclusively in small-sized lobsters and C. rodgersii in lobster of various sizes, though at a lower frequency. Using open water mesocosms I presented two urchins of one species to 14 S. verreauxi during nocturnal feeding trial

It has been speculated that Sagmariasus verreauxi (Eastern Rock Lobster) is an important predator of the barrens-forming urchin species Centrostephanus rodgersii (Long-Spined Urchin) and Heliocidaris erythrogramma (Short-Spined Urchin). Both urchin species can cause extreme habitat modification when occurring at high densities and this is considered a problem within NSW marine parks. Elsewhere, lobster predation on urchin by similar species Jasus edwardsii (Southern Rock Lobster) is considered key in controlling urchin populations, but whether S. verreauxi has a similar trophic impact is unknown. In this study, I for the first time investigate the likely value of S. verreauxi as an urchin control agent. I use a holistic approach that investigates lobster diet and feeding behaviour by using dissections and feeding trials and investigate urchin predation rates inside and outside of No-Take Sanctuary Zones (SZ’s) using diver surveys and urchin tethering experiments. I also use external tagging and passive-receiver acoustic telemetry to observe whether large and small lobster use and remain resident within sanctuary zones. Additionally, I have collated 125 observations on lobster size (carapace length, mm) between all experimental locations to test whether larger S. verreauxi are associated with SZ’s. My dissections and Gut Contents Analysis (GCA) of 118 S. verreauxi freshly collected and donated frozen from areas within the Sydney, Shoalhaven, Illawarra and Central Coast regions of NSW imply that lobsters eat urchins less frequently than expected and did not support the prediction that large lobsters eat more urchins. I found urchin material in < 20% of the 118 lobsters dissected and did not find urchin in 96 individuals. I found H. erythrogramma exclusively in small-sized lobsters and C. rodgersii in lobster of various sizes, though at a lower frequency. Using open water mesocosms I presented two urchins of one species to 14 S. verreauxi during nocturnal feeding trial

It has been speculated that Sagmariasus verreauxi (Eastern Rock Lobster) is an important predator of the barrens-forming urchin species Centrostephanus rodgersii (Long-Spined Urchin) and Heliocidaris erythrogramma (Short-Spined Urchin). Both urchin species can cause extreme habitat modification when occurring at high densities and this is considered a problem within NSW marine parks. Elsewhere, lobster predation on urchin by similar species Jasus edwardsii (Southern Rock Lobster) is considered key in controlling urchin populations, but whether S. verreauxi has a similar trophic impact is unknown. In this study, I for the first time investigate the likely value of S. verreauxi as an urchin control agent. I use a holistic approach that investigates lobster diet and feeding behaviour by using dissections and feeding trials and investigate urchin predation rates inside and outside of No-Take Sanctuary Zones (SZ’s) using diver surveys and urchin tethering experiments. I also use external tagging and passive-receiver acoustic telemetry to observe whether large and small lobster use and remain resident within sanctuary zones. Additionally, I have collated 125 observations on lobster size (carapace length, mm) between all experimental locations to test whether larger S. verreauxi are associated with SZ’s. My dissections and Gut Contents Analysis (GCA) of 118 S. verreauxi freshly collected and donated frozen from areas within the Sydney, Shoalhaven, Illawarra and Central Coast regions of NSW imply that lobsters eat urchins less frequently than expected and did not support the prediction that large lobsters eat more urchins. I found urchin material in < 20% of the 118 lobsters dissected and did not find urchin in 96 individuals. I found H. erythrogramma exclusively in small-sized lobsters and C. rodgersii in lobster of various sizes, though at a lower frequency. Using open water mesocosms I presented two urchins of one species to 14 S. verreauxi during nocturnal feeding trial

Spiny lobsters (Palinuridae) are capable of emitting sounds called antennal rasps. In the bioacoustics literature, such broadband sounds have mostly been characterized from tank recordings where reverberation and resonant frequencies might strongly distort their features. Hence, in this study, we compared antennal rasps produced by European spiny lobsters Palinurus elephas in both tank and in situ conditions. We found significant differences in all sound features (temporal, intensity and spectral features) between tank and in situ recordings, confirming that antennal rasps—and broadband sounds generally—cannot be accurately characterized in tanks if sound reverberation is ignored. In recordings of antennal rasps made in situ, we show that the main acoustic power is located in the low frequency band (below 1 kHz), which was missed by all earlier studies done in tanks where such low frequencies cannot be properly measured. The hearing capacities of crustaceans suggest roles for intra-specific communication of these sounds, and their high levels indicate they could be heard above noise. Indeed, we outline that antennal rasps are among the loudest sounds known in the marine animal kingdom, with peak-to-peak sound pressure levels (calculated at 20 cm from the source) above 175.7 dB re 1 µPa2, and peak-to-peak source levels (estimated at 1 m from the source) ranging from 154.2 to 160.6 dB re 1 µPa2. These acoustic properties imply they could be detected in situ during passive acoustic monitoring. This study also highlights the importance of using appropriate measurement methods when characterizing sounds produced by marine invertebrates.

Most fisheries involving spiny lobsters of the genus Palinurus have been overexploited during the last decades, so there is a raising concern about management decisions for these valuable resources. A total of 13 microsatellite DNA loci recently developed in Palinurus elephas were assayed in order to assess genetic diversity levels in every known species of the genus. Microsatellite markers gave amplifications and showed polymorphism in all species, with gene diversity values varying from 0.650 6 0.077 SD (Palinurus barbarae) to 0.792 6 0.051 SD (Palinurus elephas). Most importantly, when depth distribution was taken into account, shallower water species consistently showed larger historical effective population sizes than their deeper-water counterparts. This could explain why deeper-water species are more sensitive to overfishing, and would indicate that overexploitation may have a larger impact on their longterm genetic diversity.

Zoals in de vorige editie beschreven, houdt South Sea Exclusive zich bezig met maricultuur van exclusieve marine soorten met als specialisatie de langoest. De langoest is in Azië al eeuwen een zeer gewild product, waaraan forse prijzen gekoppeld zijn. Dit heeft een aantal decennia geleden al geleid tot overexploitatie, maar tot op heden zijn er nog geen succesvolle (commerciële) kweekinitiatieven voor langoesten opgezet. In dit artikel beschrijf ik het belangrijkste initiatief in Australië om (warmwater) langoesten van het genus Panulirus te kweken. We eindigen met een overzicht van huidige onderzoeksonderwerpen van South Sea Exclusive. Maar laten we beginnen met een korte beschrijving van de biologie van de warmwater langoest, om zodoende meer inzicht te krijgen in de potenties en restricties van dit genus inde maricultuur

In het derde artikel over South Sea Exclusive, een bedrijf gespecialiseerd in de duurzame maricultuur van exclusieve mariene soorten, staan de factoren achter de vraag naar levende langoesten in de doelmarkten China, Maleisië en Japan centraal. Eerst een korte uitleg over de kreeftenindustrie in zijn geheel

Molecular data can aid in the resolution of conflicting hypotheses generated through difficulties in the interpretation of morphological data and/or an incomplete fossil record. Moreover, the reconstruction of phylogenetic relationships using molecular data may help to trace back the origin of morphological innovations which had a major impact on the radiation of a taxonomical group. In this work, different nuclear (18S, 28S, and H3) and mitochondrial (16S and COI) gene regions were sequenced in a total of 35 Achelatan species to test conflicting hypotheses of evolutionary relationships within the Achelata infraorder and solve the taxonomic disagreements in the group. The combined molecular dataset strongly supports the hypothesis that Achelata is a monophyletic group composed of two main families: Palinuridae and Scyllaridae. Synaxidae is found to be a polyphyletic group, which should be included within Palinuridae. Consequently, our results indicate that the origin of the stridulating organ occurred only once during Achelata evolution. Finally, the two main clades found within the Scyllaridae are in agreement with previous inferences based on adult morphological data. The dating of divergence of Achelata obtained with a relaxed-clock model is compatible with previous hypotheses of a Triassic origin of the Achelata

Drie Wageningse studenten gaan een langoestenkwekerij op de Filippijnen beginnen. Dat ambitieuze plan ontstond op stage. 'Ik heb geen zin om milieueffectrapportages van de Betuwelijn te maken. Hier kan ik aan mijn idealen werken en hebben mijn inspanningen meer effect', vertelt Peter van der Werf. Met hun businessplan doen de vrienden begin december mee aan de finale van een internationale wedstrijd, de BiD Challenge

The external morphology of the first phyllosoma larva of the spiny lobster Palinurus mauritanicus is described based on hatched larvae, and compared with those described in other Palinurids. This constitutes the first scanning electron microscopy description of a phyllosoma of the genus Palinurus and the first complete description of a phyllosoma stage of P. mauritanicus. The first phyllosoma larva of P. mauritanicus hatches in a very advanced stage, compared to other palinurid genera, which would allow it to stay in the plankton for a shorter period of time. We cannot point out any major morphological differences from the congeneric species Palinurus elephas, co-occurring in most of its distribution area. The first phyllosoma larva of P. mauritanicus can be differentiated from those described for the genus Panulirus as well as from those of Scyllarus and Scyllarides widely co-occurring in the distribution area of P. mauritanicus, by the pereiopods 4 and 5 being already present as small buds and by the long, non-setose exopod on pereiopod 3. The morphology and differential position of the chromatophores of the living animal are also described

The neuronal firing patterns in the pyloric network of crustaceans are remarkably consistent among animals. Although this characteristic of the pyloric network is well-known, the biophysical mechanisms underlying the regulation of the systems output are receiving renewed attention. Computer simulations of the pyloric network recently demonstrated that consistent motor output can be achieved from neurons with disparate biophysical parameters among animals. Here we address this hypothesis by pharmacologically manipulating the pyloric network and analyzing the emerging voltage oscillations and firing patterns. Our results show that the pyloric network of the lobster stornatogastric ganglion maintains consistent and regular firing patterns even when entire populations of specific voltage-gated channels and synaptic receptors are blocked. The variations of temporal parameters used to characterize the burst patterns of the neurons as well as their intra-burst spike dynamics do not display statistically significant increase after blocking the transient K-currents (with 4-aminopyridine), the glutamatergic inhibitory synapses (with picrotoxin), or the cholinergic synapses (with atropine) in pyloric networks from different animals. These data suggest that in this very compact circuit, the biophysical parameters are cell-specific and tightly regulated. (c) 2006 Wiley Periodicals, Inc.

The neuronal firing patterns in the pyloric network of crustaceans are remarkably consistent among animals. Although this characteristic of the pyloric network is well-known, the biophysical mechanisms underlying the regulation of the systems output are receiving renewed attention. Computer simulations of the pyloric network recently demonstrated that consistent motor output can be achieved from neurons with disparate biophysical parameters among animals. Here we address this hypothesis by pharmacologically manipulating the pyloric network and analyzing the emerging voltage oscillations and firing patterns. Our results show that the pyloric network of the lobster stornatogastric ganglion maintains consistent and regular firing patterns even when entire populations of specific voltage-gated channels and synaptic receptors are blocked. The variations of temporal parameters used to characterize the burst patterns of the neurons as well as their intra-burst spike dynamics do not display statistically significant increase after blocking the transient K-currents (with 4-aminopyridine), the glutamatergic inhibitory synapses (with picrotoxin), or the cholinergic synapses (with atropine) in pyloric networks from different animals. These data suggest that in this very compact circuit, the biophysical parameters are cell-specific and tightly regulated. (c) 2006 Wiley Periodicals, Inc.

Se describen estadios de puerulus y postpuerulus de la langosta espinosa de profundidad, n.v.: langosta de Valparaíso, Projasus bahamondei. El material fue obtenido en pescas de arrastre comerciales de langostinos y camarón nailon. Existe variabilidad entre los distintos ejemplares de larvas y postlarvas estudiados. El tamaño de los ejemplares es mayor que el puerulus de otras especies de palinúridos. P. bahamondei, del talud continental de Chile, archipiélago de Juan Fernández, islas Desventuradas y del cordón submarino de Nazca, junto a P. parkeri de Sudáfrica, Nueva Zelanda e isla Saint Paul en el océano Indico y Projasus sp. de New South Wales, Australia, pertenecen a un género circumpolar de profundidad, filogenéticamente muy antiguo, de origen Gondwánico. Se comparan los estadios descritos con aquéllos de P. parkeri y Projasus sp.