Lobster Population Research Articles

Shifts in habitat use and demography of American lobsters in coastal Maine (USA) over the past quarter century

Some species are so linked to specific environments that their habitat association almost becomes a species-defining character and is used by managers and policymakers to direct their conservation. The American lobster Homarus americanus is among the most valuable fisheries species in North America and among the best studied benthic marine invertebrates in the world. Its populations and habitats have been studied and detailed in publications for over 35 yr. This lobster species was known to dwell in shelters, and their populations had historically been concentrated in shelter-providing boulder habitat. Our study revisited 20 long-term monitored sites at 10 m depth along more than 320 km of the Gulf of Maine. Surprisingly, we recorded fundamental changes in lobster abundance, habitat use, and distribution. Specifically, lobster population densities declined overall and occupancy in boulder habitats declined 60%, while densities on featureless ledge and sediment habitats increased 633 and 280%, respectively, from 2000 to 2019. Lobster rock shelter occupancy declined in recent years, but average body size increased, due in part to declines in smaller size classes. These demographic changes may result from both reduced recruitment and intraspecific competition resulting from the lower population densities. Habitat changes at our monitored sites included declines in kelp abundance, increases in diminutive algal turfs, and nearly 3°C warming of benthic water temperature in July (1995-2021), some of which may have contributed indirectly to those shifts. While these changes in shallow water habitat and demography have implications for the lobster fishery and stock assessments, it also illustrates previously undescribed behavioral plasticity.

Using marine protected areas to assess the status and recovery of the spiny lobster Jasus edwardsii fishery in the Hauraki Gulf, Aotearoa New Zealand

The value of no-take marine protected areas (MPAs) in providing fisheries-independent information to evaluate the status of adjacent fish stocks is increasingly being recognised. However, to ensure robust assessments of fisheries using this approach, MPAs need to be representative of the wider fished area and sampling should include multiple MPA and fished locations spanning the area of interest. The spiny lobster Jasus edwardsii fishery in Aotearoa New Zealand’s Hauraki Gulf has been in decline since the late 1990s, but latest stock estimates suggest a dramatic recovery following catch reductions in 2018. We compared J. edwardsii populations on shallow reefs (<20 m depth) in three marine reserves with six fished locations across the Hauraki Gulf to provide a fisheries-independent assessment of this important fishery and the degree of recovery following catch reductions. Region-wide surveys found that J. edwardsii populations within protected areas were dominated by large, legal-size individuals, whereas lobster in fished locations were mostly below or around legal-size. Total, vulnerable, and spawning stock biomass was 12-43 times higher within MPAs compared to fished locations. Overall, biomass at fished locations was <10% of that in reserves and there was little evidence of recovery following catch reductions. Our fisheries-independent data suggest that recent stock assessments have severely overestimated the recovery and state of lobster populations in the Hauraki Gulf and that populations on shallow reefs remain depleted. These findings highlight the critical need for fisheries-independent data and the value of MPA monitoring data in evaluating population status and recovery following fisheries management actions.

Sea surface temperature and current-related parameters affecting local adaptation of scalloped spiny lobster population in Indonesia’s archipelagic system

The Scalloped Spiny lobster (Panulirus homarus, Linnaeus 1758) known as one of the commercially harvested Panilurid lobster. This species was distributed widely across continents. Indonesia, as one of the largest archipelagic systems in the world, was also distribution area of the Scalloped Spiny lobster. These facts have led to questions regarding spiny lobster harvest and culture management by considering population differentiation and habitat fragmentation on complex and distinct archipelagic islands. Our investigation was conducted using high-density SNPs datasets from several spiny lobsters harvested from five locations in Indonesia. We found strong differentiation among spiny lobster populations clustered into 3 sub-populations. Environment association analysis and Fst analysis revealed outlier loci significantly associated with Sea Surface Temperature variation and potentially correlated with Sea Current-related parameters. The evidence of a structured population of scalloped spiny lobsters in Indonesia can serve as a consideration in the management of spiny lobsters.

Genetic Diversity of Panulirus Versicolor in the Waters of Barrang Caddi Island, Makassar Strait, South Sulawesi, Indonesia

Barong shrimp or lobster (Panulirus versicolor) is a fishery commodity with high economic value and great demand. This study aims to determine the genetic characteristics of Panulirus versicolor at the fishing location in the waters of Barrang Caddi Island, Makassar Strait, using primers LCO-1490F and HCO-2198R. Genomic DNA extraction was performed using a Quick-DNA Tissue Miniprep Kit for total isolation. For DNA purity, the elution buffer utilized in this research was specifically selected for its suitability for PCR amplification with KOD FX Neo, providing optimal conditions for efficient genetic analysis. The primary genes used were LCO-1490F with primers GGT CAA CAA ATC ATA AAG ATA TTG G, and HCO-2198R with TAA ACT TCA GGG TGA CCA AAA AAT CA. The study utilized a 1% agarose gel in a 1X TBE buffer at 50 voltage for 45 minutes to move the total DNA and PCR products. The analysis results at sampling stations 0.2-03 showed increasingly smaller genetic distances. Based on the results of BLASTn analysis, each station had the same type of Panulirus versicolor with a similarity of 99-100%. The morphological characteristics included a carapace with a black spot and black and white lines on each abdominal segment. The analysis of genetic variation in the lobster population on Barrang Caddi Island using primers LCO-1490F and HCO-2198R obtained a DNA fragment of 700 bp. The population of Panulirus versicolor lobster on Barrang Caddi Island showed a high level of similarity or low diversity.

Gastric mill ossicles record chronological age in the Caribbean spiny lobster (Panulirus argus)

Information on individual age and size relationships is crucial for sustainable management of fished populations. Previous research has indicated it may be possible to directly age crustaceans by counting annular bands deposited within gastric mill ossicles. The method has been applied to multiple crustacean species; however, its applicability has been controversial because studies have shown gastric mill ossicles are reworked and/or replaced during ecdysis. Over the last 8 years, we have refined and improved upon methods of processing gastric mill ossicles and investigated the validity of this method for ageing Caribbean spiny lobster (Panulirus argus) using captive-raised animals of known age from the Florida Keys (USA). Although the biological process that creates annular bands within gastric mill ossicles remains unclear, validation of the method for P. argus based on known-age lobsters from 10 months–5.5 years old (n = 33) confirms that the deposition of bands correlates with chronological age. We compared precision and accuracy of age estimates for ossicles processed using two imaging techniques (transmitted vs. reflected light) and found that transmitted light provided the best images for ageing P. argus. The mean coefficient of variation (CV) of age estimates between two readers was 20.2 %. The consensus age estimates provided by the readers were, on average, within 0.5 years of the known age and overall, 94 % of consensus age estimates from readers were within 1 year of the known age. We also compared lobsters of the same size but different age as well as those of the same age but different size to address whether the number of endocuticular bands in the ossicle is a measure of true chronological age or simply related to the size of the animal. Our results suggest that the gastric mill ossicles record chronological age in P. argus, providing a reliable ageing method with which to inform age-based management of the Caribbean spiny lobster population. Future research is needed to understand the mechanism that controls the deposition of endocuticular bands within the crustacean gastric mill ossicles and to determine the applicability of the method for other crustaceans.

Genetic divergence and adaptation of an isolated European lobster population in the Netherlands

Abstract Identifying isolated populations is a key step towards enacting effective conservation management. European lobsters (Homarus gammarus) from Oosterschelde in the Netherlands are subject to fishery pressure and have previously been reported as genetically differentiated. They are also putatively of transplanted origin and have subsequently endured recent bottlenecking and environmental change. We assessed Oosterschelde lobsters to evaluate their demographic independence and appraise potential founder effects and evolutionary responses to isolation. Using restriction-site associated DNA sequencing, we genotyped 6185 single nucleotide polymorphisms across 188 individuals from 27 sites across the Atlantic range of H. gammarus to investigate population genetic diversity, structure, and potential adaptation. Our results show that Oosterschelde lobsters are genetically divergent from other stocks. We evidence extensive differentiation via both neutral and outlier loci, indicative of strong biophysical and demographic isolation, and detect signatures of reduced genetic diversity that may reflect weak founder effects or subsequent population contractions. Among outlier loci, we identify candidates for range-wide local adaptation via variants in genes of important biological functionality and link a private allele of Oosterschelde to a locus potentially conveying adaptive tolerance to environmental hypoxia. Given our findings, we advise proactive monitoring of Oosterschelde lobsters to explore whether existing management measures effectively conserve this discrete, self-recruiting population.

Predators of the sea urchin Diadema mexicanum (Diadematoida: Diadematidae) at the Eastern Tropical Pacific coral reefs

Introduction: The coral reefs of Isla del Coco National Park are some of the most pristine ecosystems on Earth. The sea urchin Diadema mexicanum (Diadematoida: Diadematidae) is a common inhabitant with a pivotal role in the ecology of this unique ecosystem.
 Objective: In this study, we identified the predominant predators of D. mexicanum and estimated the predatory consumption rates. We also determined predation rates at different sea urchin sizes and at sites with contrasting refuge availability.
 Methods: We use field video recording observations and tethering experiments.
 Results: The balistid Sufflamen verres and the labrid Bodianus diplotaenia were identified as predators of small and medium size D. mexicanum; the labrids Thalassoma grammaticum and B. diplotaenia (juvenile) and the tetraodontid Arothron meleagris were attempted predators; and Canthigaster punctatissima and Holacanthus passer were scavengers. Larger sea urchins (> 30 mm) were also preyed upon during the tethering experiments. Furthermore, a clear effect of the site on survival of the different sea urchins’ sizes was noted. No difference in the sea urchin predator biomass was found among sites, which highlights the importance of site complexity on survival. At high and medium complexity sites, large individuals had better survival, while at the low complexity site, there was almost no differences in survival rates among the three size classes. Our results also show that a high abundance of these predatory fishes, above 0.04 ind m-2, guarantees a low sea urchin density. Below this threshold, a higher variability in sea urchin density is observed Despite not being registered with the video recordings, lobsters were observed once preying upon a large sea urchin individual.
 Conclusions: This study identifies a keystone fish guild with high predation rate for Diadema in the National Park, which suggests that protective actions have positively benefited predatory fish and lobster populations.

Effect of acclimation temperature on thermal tolerance between American lobster (Homarus americanus) collected in different lobster fishing areas in Atlantic Canada

The American lobster fishery is the most economically significant commercial fishery in Atlantic Canada and takes place in waters that are warming due to climate change. Lobster are poikilotherms that tolerate a wide range of seasonal temperatures with an optimal range of 12–18 °C. Lobster in the Canadian Maritimes may be naturally acclimated to a wide range of temperatures and thus, could have a wide range of thermal tolerance that may be distinct across regions. The present study used non-invasive open-source tools to explore differences in thermal tolerance in real time between geographically separated lobster populations from around the Canadian Maritimes. Lobsters were acquired from six lobster fishing areas in the Canadian Maritimes and acclimated to either warm (15 °C) or cold (5 °C) water for two weeks before the onset of thermal trials. Geographic origin was not a significant predictor of estimated thermal maximum, while acclimation temperature was a significant predictor. These results suggest that thermal tolerance is more strongly linked to acclimation temperature than to geographic region.

Observed size distribution changes in American lobsters over a 12-year period in southwestern Nova Scotia, Canada.

Size distribution and size frequency information of American lobsters (Homarus americanus) are often used to help estimate the age distributions, and reproductive output for the species and to guide the determination of appropriate minimum legal sizes for the fishery. This study used truncated linear regression models to estimate the effects of sampling year, sampling month, lobster sex and water depth on the lobster size. A dataset of almost 130,000 trap-caught lobsters from the two most important lobster fishing areas of Atlantic Canada collected over a 12-year period (2004-2015) was analyzed. It was shown that truncated models can help to account for biases due to the trap sampling method from vessels and from wharf samplings. There were significant annual and seasonal changes in size distribution, and data collected outside the fishing season showed a significant increase in carapace length in 2014 and 2015, potentially reflecting a northward shift of the range of lobster populations due to more favourable settlement and recruitment habitats. Size also increased in late summer, likely due to moult. Our results demonstrated that landed lobsters, especially females, were smaller than the predicted size-at-maturity in the region (96.5 mm carapace length), which could have long-term repercussions for the stock's reproductive potential.

Evidence of Considerable Shifts in Catch Composition in the Artisanal Spiny Lobster Fishery in Kenya.

The artisanal lobster fishery in Kenya is small in world terms but important locally both in terms of supporting local fishing communities and generating revenue for the government. Despite its socioeconomic importance, detailed knowledge of many aspects of the fishery is lacking. The study reported herein aimed to investigate and provide information on the population structure and catch composition of spiny lobsters caught by artisanal fishers off six major landing sites along the coastline. A total of 2711 lobsters representing five palinurid species were collected during the study period (November 2000-March 2001). Among the five species, Panulirus longipes dominated the catches in Msambweni (75%) and Shimoni (58%), P. homarus in Mambrui (70%) and Kipini (72%), P. ornatus in Lamu (49%), and P. penicillatus in Kilifi (39%). P. versicolor was the rarest species observed in the catches across the six sites. The overall catch consisted of 33% P. ornatus, 32% P. homarus, 28% P. longipes, 6% P. penicillatus and 2% P. versicolor. Sitewise, Lamu contributed 31% of the overall catch, Kipini 23%, Shimoni 20%, Mambrui 13%, Msambweni 7%, and Kilifi 6%. A comparison of the results of this study and lobster abundance data from 1970s surveys revealed considerable shifts in the catch composition of artisanal landings over time. Future work on this fishery should concentrate on the lobster populations in the decades-old marine protected areas to obtain unfished reference data to assess the fishery and establish the underlying cause(s) of the observed shifts in catch composition.

Before–after control–impact (BACI) assessment of the effects of a deep-water no-take fishery reserve to recover Norway lobster (Nephrops norvegicus) overfished populations and coexisting megafauna

AbstractOne of the main drivers of marine ecosystem change is fishing activity, bottom trawling being the most intensive fishing practice affecting benthic ecosystems worldwide. In the western Mediterranean Sea, Norway lobster stocks present signs of overexploitation due to trawling pressure, as their biomass and abundance have decreased abruptly during the last few years. No-take fishery reserves, a type of marine protected area where fishing is prohibited, could be efficient management measures to recover Norway lobster overexploited populations and coexisting demersal megafauna. Adopting a BACI (before–after control–impact) approach, we performed experimental fishing surveys before and after 4 years of the implementation of a deep-sea no-take reserve in the northwestern Mediterranean. After 4 years of closure, the Norway lobster population increased in abundance, biomass, body size, and trophic level in the no-take reserve. Our approach also revealed an increase in Norway lobster biomass beyond its boundaries, suggesting a spillover effect. Other demersal fish species also increased in biomass and abundance in the no-take reserve. Based on the results of this study, we suggest that no-take reserves might be an effective measure for recovering the Norway lobster stock and some species present in the same habitat.

Cannibalism in cultured juvenile lobster Panulirus ornatus and contributing biological factors

Cannibalism is a major limitation to communally culturing the spiny lobster, Panulirus ornatus, and although frequently reported in research it is yet to be thoroughly investigated. To support continued innovation in culture, we must understand the contribution of cannibalism to juvenile mortality and identify influencing factors. This was accomplished through 900 h of time-lapse photography of three populations of juvenile lobsters over 30 d, including all ecdysis and cannibalism events to inspect individual weight, tank biomass, moult-stage, sex, and injury, as possible contributing factors. Total mortality was over 50% and attributed to the attack and cannibalism of moulting lobsters. Between 20 and 25% of moulting events in P. ornatus resulted in cannibalism of the moulting lobster. Population control and biomass stabilisation appear to be consequences of cannibalism, determined by fluctuations in tank biomass. Additionally, the moult stage of killer cannibals may suggest a nutritional benefit for lobsters in the latter half of the moult cycle. An increase in the average locomotor activity within a population during the hour before cannibalism occurs indicates that the factors driving cannibalism are present up to an hour before a moult. Here we demonstrate the flaws of previous assumptions related to the type and frequency of cannibalism in cultured P. ornatus systems and highlight contributing factors which warrant further study. Building from this research we may identify drivers of cannibalism among juvenile P. ornatus, with the aim of mitigating this behaviour in research and industry culture.

Carapace microbiota in American lobsters (Homarus americanus) associated with epizootic shell disease and the green gland.

Epizootic Shell Disease (ESD) has posed a great threat, both ecologically and economically, to the American lobster population of Long Island Sound since its emergence in the late 1990s. Because of the polymicrobial nature of carapace infections, causative agents for ESD remain unclear. In this study, we aimed to identify carapace microbiota associated with ESD and its potential impact on the microbiota of internal organs (green gland, hepatopancreas, intestine, and testis) using high-throughput 16S rRNA gene sequencing. We found that lobsters with ESD harbored specific carapace microbiota characterized by high abundance of Aquimarina, which was significantly different from healthy lobsters. PICRUSt analysis showed that metabolic pathways such as amino acid metabolism were enriched in the carapace microbiota of lobsters with ESD. Aquimarina, Halocynthiibacter, and Tenacibaculum were identified as core carapace bacteria associated with ESD. Particularly, Aquimarina and Halocynthiibacter were detected in the green gland, hepatopancreas, and testis of lobsters with ESD, but were absent from all internal organs tested in healthy lobsters. Hierarchical clustering analysis revealed that the carapace microbiota of lobsters with ESD was closely related to the green gland microbiota, whereas the carapace microbiota of healthy lobsters was more similar to the testis microbiota. Taken together, our findings suggest that ESD is associated with alterations in the structure and function of carapace microbiota, which may facilitate the invasion of bacteria into the green gland.

Settlement Preference of the Lobster Larvae on the Different Shelter Materials in the Larvae Shelter Device (LSD)

The lobster life phase is eggs, phyllosoma, puerulus, juvenile, and young lobster. The metamorphose coincides with its inshore movement and ends up into adult lobsters that inhabit the continental shelf area. The wild population of lobsters is determined by the survival rate of the puerulus. Fish larvae aggregating devices have been given significant results as a shelter or refuge area for several fish species. This device is then referred to as the Larva Shelter Device (LSD). The question is whether there is a preference for lobster larvae on attractor or shelter materials. The innovation of shelter materials in LSD is cement sack paper, waring nets and gunny sacks. The number of lobster larvae in different materials was analyzed. The research was carried out in February-May 2021 at Mutiara Beach Karanggongso of Prigi Bay, Tasikmadu, Watulimo, Trenggalek, East Java, Indonesia. The identification method of puerulus species is based on taxonomic and morphological characteristics. Initial identification is done by recording and photographing species, then adjusting to the experiences of fishermen compared to Jones and Dao 2010. The study found there were 3 types of puerulus species collected including puerulus of Panulirus ornatus, P. homarus, and P. versicolor. The highest species presentation in the three shelter materials was P. homarus. The data indicate that different shelter materials had no significant effect on the species composition of the spiny lobster puerulus.

The impact of ocean warming on juvenile American lobster recruitment off southeastern Massachusetts

AbstractDuring the 1990s, coastal habitat off southeastern Massachusetts (SEMA) supported commercially viable fisheries for American lobster (Homarus americanus). Over the past two decades, landings and post‐larval settlement of lobsters in this region, which is near the southern edge of the species' range, have declined substantially, concurrent with a period of significant warming of the coastal waters off southern New England. Previous work has suggested that rising ocean temperatures may adversely impact the survival of larval and early benthic phase (EBP) lobsters and may cause adult lobsters to seek cooler offshore waters during the critical time of larval release. To investigate the manner in which the observed decline in lobster abundance may be linked to warming coastal waters, a high‐resolution hydrodynamic model was used to quantify the increase in water temperature experienced by EBP lobster off SEMA and to supply input to an individual‐based model of lobster larval transport from release areas delineated using fishery‐dependent data of late‐stage egg‐bearing lobsters. The results indicate that rising coastal water temperatures may have adversely impacted EBP lobster recruitment off SEMA by (1) causing an offshore shift in the area of larval release that resulted in a reduction in the delivery of larvae to suitable nearshore EBP habitat and (2) dramatically increasing thermal stress experienced by recently settled EBP lobsters. These findings highlight the implications of warming coastal waters on southern New England lobster population connectivity and provide insight to an understudied mechanism by which climate change affects marine species recruitment.

Rapid re-establishment of top-down control at a no-take artificial reef

Establishment of artificial reefs and no-take areas are management measures available for restoring deteriorated marine ecosystems, compensating for habitat loss and strengthening harvested populations. Following the establishment of no-take artificial reefs in western Sweden to compensate for hard bottoms lost to a shipping lane, we detected rapid positive effects on crustaceans and demersal fish compared to fished reference areas. The relative abundance and size structure of European lobster (Homarus gammarus) increased strongly in the no-take area indicating more than doubled and tripled egg production in 5 and 10 years, respectively. For benthic fish and crustacean communities, the abundances of gadoids and wrasses increased and the abundances of small decapod crustaceans decreased in the no-take area, likely indicating cascading effects of increased predation. The study demonstrates that relatively small no-take areas, enhanced by artificial reefs, can rapidly invigorate populations of lobster and fish that in turn may re-initiate local top-down control.

Strong collective action enables valuable and sustainable fisheries for cooperatives

Seafood is one of the most internationally-traded food commodities. International markets can provide higher revenues that benefit small-scale fishing communities but can also drive a decline in fished populations. Collective action in collective organizations such as fishing cooperatives is thought to enhance the sustainability of fished populations. However, our knowledge of how collective action enables fishing cooperatives to achieve positive social-ecological outcomes is dispersed across case studies. Here, we present a quantitative, national-level analysis exploring the relationship between different levels of collective action and social-ecological outcomes. We found that strong collective action in Mexican lobster cooperatives was related to both sustaining their fisheries and benefiting from international trade. In the 15 year study period, lobster cooperatives that demonstrate characteristics associated with strong collective action captured benefits from trade through high catch volumes and revenue. Despite lower (but stable) average prices, the biomass of their lobster populations was not compromised to reap these benefits. Individual case studies previously found that fishing cooperatives can support both positive social and ecological outcomes in small-scale fisheries. Our results confirm these findings at a national level and highlight the importance of strong collective action. Thus, our work contributes to a better understanding of the governance arrangements to promote fishing communities’ welfare and benefits from international trade and, therefore, will be invaluable to advancing small-scale fisheries governance.

Increasing spillover enhances southern California spiny lobster catch along marine reserve borders

AbstractThe conservation benefits of marine reserves are well established but their contribution to adjacent fisheries via spillover is less certain and context‐dependent. Theoretical predictions do not always match empirical evidence from individual reserves, so carefully designed studies are essential for accurately assessing spillover and its contribution to fisheries. Biomass buildup within reserves, and spillover from reserve borders, also usually takes time to develop. In 2003, a network of no‐take marine reserves was established in the Northern Channel Islands (NCI) of southern California (CA) to conserve biodiversity and to eventually enhance local fisheries through spillover of larvae, juveniles, and adults. The reserve network impacted the local CA spiny lobster (Panulirus interruptus) fishery by removing about 20% of fishing grounds in the NCI. In 2008, a collaborative fisheries research effort detected substantial lobster population increases within reserves, and an indication of the possible spillover of adult lobsters across reserve borders. To estimate whether and how much populations within reserves, and spillover from reserves, have increased through time, we repeated the sampling program 10 years later in 2018 at two of the three original reserves. Scientific trapping was conducted prior to the fishing season along a spatial gradient beginning deep within the reserves to reference sites located outside (≥2 km) of reserve borders. Results showed that legal‐sized lobster abundance in traps (catch per unit effort) increased by 125%–465% deep inside reserves, and by 223%–331% at sites near to reserve borders, and by nearly 400% just outside of reserve borders over the 10‐year period, thus indicating a substantial increase in spillover across reserve borders. A similar pattern was observed in lobster biomass caught in traps at the two reserves. This study demonstrates how spillover scales with biomass buildup and that collaborative fisheries research can be used to assess the efficacy of marine reserves as fishery management tools worldwide.

Barriers in European spiny lobster (Palinurus elephas) aquaculture: What we know so far?

AbstractPalinurids, also known as spiny lobsters, are high‐value seafood, which is economically important for many European and Asian seafood trades. However, the reduction of wild European spiny lobster populations produces a need for developing alternative renewable strategies to meet current and future demands. Aquaculture of spiny lobsters has the potential to become of major economic importance in the coming years with growing markets in Asia, Europe, and America, with Palinurus elephas being a promising candidate species for use in the commercial culture and stock enhancement of natural fisheries. This is due to its shorter larval periods and rapid growth to the critical puerulus stage compared with other spiny lobster species. While we have a basic understanding of the lifecycle and biology of P. elephas, much of this is based on work undertaken on similar species globally. There are many gaps in our knowledge that need to be addressed to make its aquaculture viable with appropriate feeds being an immediate issue as well as many other husbandry‐related factors. Previous studies act as a platform providing a baseline for further research and highlighting constraints. Developments in the use of P. elephas are promising due to realistically bridgeable knowledge gaps, the likelihood of producing sustainable food and the high commercial value of spiny lobsters. This review identifies our present state of knowledge and outlines the scope for further research and necessary technological developments to make it a viable contribution towards crustacean aquaculture in Europe.

Co-existence in practice: a collaborative study of the effects of the Westermost Rough offshore wind development on the size distribution and catch rates of a commercially important lobster (Homarus gammarus) population

Abstract The global expansion of offshore windfarms (OWF), whilst seen as a tool to combat climate change, can often be of concern to fishing communities already challenged by spatial restrictions. Static gear fisheries, due to their strong fidelity to specific sites, can be particularly affected by spatial conflict with OWF. Here we investigate, using four sampling efforts over a six-year period, the effects of the development of the Westermost Rough OWF (UK) on a commercially important European Lobster (Homarus gammarus) population. A collaborative study was developed and conducted by the local fishery and the developer. A baseline potting survey was conducted ∼ every 4 days over the summer months of 2013 (pre-construction) and post-construction surveys were conducted in 2015, 2017, and 2019. Size, catch, and landings per unit of effort (CPUE & LPUE) of all lobsters were recorded and compared between sites and between years. Size structure and catch rates differed between years, however differences were not observed in comparisons of the windfarm and export cable to their associated control sites within each year, although there were compounding factors associated with the proximity of the control sites to the treatment sites. There was a short-term increase in size and catch rates of lobsters associated with the construction phase of the windfarm site, but this was not observed during the subsequent operational phase surveys. Although the impacts of windfarms on fisheries will vary on a case-by-case basis, this study has implications for the expansion of offshore wind developments on other static gear crustacean fisheries.