Homarus Americanus Research Articles

Bioinspired hybrid helical structure in lobster Homarus Americanus: Enhancing penetration resistance and protective performance

The high impact and penetration resistance of the cuticle in the lobster Homarus americanus can be attributed to its unique twisted plywood structure. Hybridization of two helical structures was observed in the exoskeleton, with different pitch angles and ply thickness of the exocuticle and endocuticle within the exoskeleton. Given the survival challenges posed by the natural environment, it is worthwhile to study why it evolved into a hybrid helical rather than a uniform helical structure. In light of this, we have proposed an innovative bionic hybrid helical structure design strategy that goes beyond simply reducing the pitch angle. In this paper, we replicated complex biological microstructures by introducing two types of pitch angles and ply thicknesses for regional configurations. Quasi Static Indentation (QSI) full-penetration experiments were conducted. Experimental results revealed that the exocuticle with a large pitch angle and small ply thickness possesses a higher knee load under the penetration test, which provides a higher initial damage threshold. On the other hand, the endocuticle with a small pitch angle and large ply thickness induces higher damage dissipation, which provides superior protective performance. These research findings demonstrate that ply hybridization can be a promising method for microstructure design to improve the penetration resistance of thin laminates and serve as a reference for developing more refined gradient helical structure designs.

Photographic characterisation of acidification-induced larval malformations in the European lobster Homarus gammarus (Linnaeus, 1758) (Decapoda: Astacidea: Nephropidae)

Abstract Occurrence of developmental malformations is of interest since they potentially influence organismal performance and fitness. We report an increased incidence (⁓ 46 fold) of physical malformations in the larvae of the American lobster Homarus Gammarus (Linnaeus, 1758) in response to seawater acidification (–0.58 pH units relative to nominal pH 8.0). We observed three malformations under the influence of seawater acidification previously undescribed in lobster larvae: a flared carapace, twisted tail, and cross claw. Larvae reared under seawater acidification exhibit significantly lower survivorship (by ⁓14%) and the occurrence of a malformation decreases survivorship (12.7%). Larvae with four types of malformations did not progress through development to reach post-larval stages. Namely, these malformations were a flared carapace, curled carapace, twisted tail, and cross claw. Results from this study provide photographic documentation of various lobster larval malformations that ultimately affect individual success and can be applied for quality-control in hatcheries.

Long-read sequencing reveals the shell microbiome of apparently healthy American lobsters Homarus americanus from Atlantic Canada.

The shell microbial community of lobsters-a key factor in the development of epizootic shell disease (ESD)-is still insufficiently researched in Atlantic Canada and many knowledge gaps remain. This study aimed to establish a baseline description and analysis of the shell microbiome of apparently healthy lobsters from four locations in the region. More than 180 lobster shell swab samples were collected from New Brunswick, Nova Scotia and Prince Edward Island (PEI). PacBio long-read 16S rDNA sequencing and bioinformatic analyses in QIIME2 identified the shell-associated bacteria. The shell microbiome of healthy lobsters consisted mainly of the bacterial classes Gammaproteobacteria, Saprospiria, Verrucomicrobiae, Alphaproteobacteria, Flavobacteriia, Acidimicrobiia and Planctomycetia. The microbial composition differed regionally and seasonally, with some classes showing decreased or increased relative abundances in the PEI samples as well as in the winter and spring samples in Nova Scotia. The core shell microbiome included potentially pathogenic as well as beneficial bacterial taxa, of which some were present only in certain regions. Bacterial taxa that have previously been associated with ESD were present on healthy lobsters in Atlantic Canada, but their frequency differed by location, sampling time, and moult stage. This study indicated that geographical and seasonal factors influenced the shell microbiome of apparently healthy lobsters more than host factors such as sex, size, and moult stage. Our results provide valuable reference microbial data from lobsters in a disease-free state.

Industry and conservation goals are complementary for the most valuable fishery in the United States under climate‐driven life history changes

AbstractCrustaceans, which are highly susceptible to the effects of climate change, are critical for food security worldwide. Yet, management rarely evaluates the performance of alternative regulatory strategies under climate‐driven life history change. This limits the development of climate‐ready management plans, undermining fisheries sustainability. We compared the performance of alternative minimum legal size (MLS) regulations under shifts in growth and maturity for American lobster in the Gulf of Maine, the most valuable single‐species commercial fishery in the United States. Across the life history change scenarios examined, increasing MLS improved status indicators, while decreasing MLS eroded status indicators for spawning stock biomass, legal abundance, landings, and exploitation rate. Our results demonstrate that protecting the lobster stock by increasing MLS improves fishery output, highlighting that conservation and industry goals can be complementary. This study exemplifies the utility of MLS as a conservation measure for crustacean fisheries under climate change.

Concentration and condition of American lobster postlarvae in small‐scale convergences

AbstractInvertebrate larvae are often abundant in the surface ocean, which plays a key role in their dispersal and connectivity. Pelagic microhabitats characterized by small‐scale hydrographic variability are complex and ubiquitous in the coastal ocean, but their study is challenging, and they have been largely neglected in meroplankton ecology. Surface convergences, i.e., surface microhabitats featuring convergent horizontal currents, may aggregate the last larval stage of the American lobster and could provide shelter and food for Stage IV postlarvae and thus enhance their condition. We tested these hypotheses by conducting a series of cruises in the southwestern Gulf of Maine in summer 2021, sampling 15 paired sets of potential convergences and off‐convergence unstructured habitat. We measured postlarval abundance, surface hydrography, acoustic backscatter, and circulation. Experiments and image analysis compared condition, color, and morphology of postlarvae sampled inside and outside potential convergences. Potential convergences varied in near‐surface hydrographic patterns, with most displaying consistency among two transects and diverse patterns in salinity and temperature (e.g., across‐convergence gradients with equal or different signs). While the highest postlarval abundances were found in convergences, abundance patterns on and off convergences were not consistent, and another analysis indicated higher abundance in convergences than in a 7‐year untargeted surface ocean data set. Experiments indicated no survivorship differences among convergence and non‐convergence individuals at two temperatures, while image analyses revealed differences in color and size. Physical measurements and qualitative neuston community analyses indicated substantial heterogeneity among potential convergences. Our results reinforce that small‐scale heterogeneities are highly variable but important to the ecology of meroplankton, including the pelagic and neustonic habitats where lobster postlarvae are abundant.

American lobster and Jonah crab populations inside and outside the Northeast Canyons and Seamounts Marine National Monument, USA

AbstractObjectiveThere is international pressure to increase the worldwide expanse of marine protected areas (MPAs). However, MPAs often lack preexisting long‐term biological baselines, which are essential for assessing MPA effects and for refining the conservation and socioeconomic benefits they confer to society. Our study addresses this issue by establishing demographic baselines for two commercially important species prior to a proposed fishing ban inside the Northeast Canyons and Seamounts Marine National Monument, a recently established MPA on the continental shelf break approximately 200 km southeast of Cape Cod, Massachusetts.MethodsSamples were obtained by the Commercial Fisheries Research Foundation's American Lobster and Jonah Crab Research Fleet, which is an industry‐based, fishery‐dependent data collection program. Specially trained participants recorded year‐round biological data from their 2013 to 2021 commercial catches of American lobster Homarus americanus and Jonah crab Cancer borealis. Samples were taken from an area inside the MPA and from two areas outside the MPA, spanning 130 km to the east and west.ResultAmerican lobster sizes and sex ratios varied between areas, and their sizes, sex ratios, and proportion of ovigerous females differed between submarine canyons within areas. American lobster sizes, sex ratio, proportion of ovigerous females, and prevalence of shell disease were also affected by season and/or depth. Jonah crab parameters did not vary between areas, but sex ratio varied with season and depth, and the proportion of ovigerous females varied with depth.ConclusionThese demographic baselines are the only data available, at a sufficient spatial and temporal resolution, for evaluating the effects of a proposed fishing ban in the MPA, and they fill important data gaps for stock assessments. To evaluate possible future population changes, it will be necessary to continue collecting data from inside and outside the MPA using comparable methods, and to account for the preexisting sources of variation that we have identified.

Impacts of Increasing Temperature on the Metabolism of Confined and Freely Moving American Lobsters (Homarus americanus).

AbstractGulf of Maine waters are warming rapidly, prompting a reevaluation of how commercially important marine species will respond. The goal of this study was to determine the respiratory, cardiac, and locomotory responses of American lobsters (Homarus americanus) to increasing water temperatures and to compare these to similar published studies. First, we measured the heart rate and ventilation rate of 10 lobsters that were confined in a temperature-controlled chamber while exposing them to gradually warming temperatures from 16 to 30 °C over 7 h. Both heart rate and ventilation rate increased along with the temperature up to a break point, with the mean heart rate peaking at 26.5 ± 1.6 °C, while the ventilation rate peaked at 27.4 ± 0.8 °C. In a subset of these trials (n = 5), oxygen consumption was also monitored and peaked at similar temperatures. In a second experiment, both the heart rate and activity of five lobsters were monitored with custom-built dataloggers while they moved freely in a large tank, while the temperature was increased from 18 to 29 °C over 24 h. The heart rate of these lobsters also increased with temperature, but their initial heart rates were lower than we recorded from confined lobsters. Finally, we confirmed that the low heart rates of the freely moving lobsters were due to the methods used by comparing heart rate data from eight lobsters collected using both methods with each individual animal. Thus, while our overall results are consistent with data from previous studies, they also show that the methods used in studies of physiological and behavioral responses to warming temperatures can impact the results obtained.

Comparing Habitat Suitability Forecasts for the Gulf of Maine and Southern New England American Lobster Stocks

Comparing Habitat Suitability Forecasts for the Gulf of Maine and Southern New England American Lobster Stocks

Elements concentrations and biomarkers in Homarus americanus from Bay of Fundy and St. Mary’s Bay, Nova Scotia, Canada

IIn this investigation, we screened the elements contamination and biomarkers responses in the American lobster, Homarus americanus from Bay of Fundy and St Mary’s Bay, Nova Scotia, Canada. To this end, concentrations of 15 element; As, Zn, Cd, Fe, Cu, Se, Mo, Mn, Sr, Hg, Pb, Co, Ni, Ca and Mg, in hepatopancreas, muscle and shell of lobsters were determined. Mo, Zn, Cu, Cd, Co, Ni and Fe reached their maximum in the hepatopancreas with 1.95, 123.56, 839.05, 59.47, 0.91, 2.11 and 79.15 μg g -1 DW respectively. While As, Hg and Se recorded their maximum in the muscles with 82.04, 1.10, 12.45 μg g -1 DW and Pb, Mn, Mg, Ca and Sr reached their highest concentrations in the shell with 1.82, 319, 12490.65, 195844.42 and 2411.52 μg g -1 DW respectively. Thus, Glutathione S Transferase (GST) and Super Oxide Dismutase (SOD) biomarkers were analyzed in addition to total protein blood concentration. Our results revealed that the American lobster could prevent the element toxicity by moving non-essential elements to the shell and absorb those essentials from the shell to the soft tissues during the deep-shallow water migration. In addition, according to national and international standards guidelines concentrations, we can assume that the edible muscles of lobsters from Bay of Fundy and St. Mary’s Bay are in good quality for all studied elements except for Se. Moreover, Principal Components Analysis (PCA) showed clear segregation between the elements that are classified as toxic and those classified as essentials

Changes in Temperature Alter the Toxicity of Polycyclic Aromatic Compounds to American Lobster (Homarus americanus) Larvae.

Polycyclic aromatic compounds (PACs) present in the water column are considered to be one of the primary contaminant groups contributing to the toxicity of a crude oil spill. Because crude oil is a complex mixture composed of thousands of different compounds, oil spill models rely on quantitative structure-activity relationships like the target lipid model to predict the effects of crude oil exposure on aquatic life. These models rely on input provided by single species toxicity studies, which remain insufficient. Although the toxicity of select PACs has been well studied, there is little data available for many, including transformation products such as oxidized hydrocarbons. In addition, the effect of environmental influencing factors such as temperature on PAC toxicity is a wide data gap. In response to these needs, in the present study, Stage I lobster larvae were exposed to six different understudied PACs (naphthalene, fluorenone, methylnaphthalene, phenanthrene, dibenzothiophene, and fluoranthene) at three different relevant temperatures (10, 15, and 20 °C) all within the biological norms for the species during summer when larval releases occur. Lobster larvae were assessed for immobilization as a sublethal effect and mortality following 3, 6, 12, 24, and 48 h of exposure. Higher temperatures increased the rate at which immobilization and mortality were observed for each of the compounds tested and also altered the predicted critical target lipid body burden, incipient median lethal concentration, and elimination rate. Our results demonstrate that temperature has an important influence on PAC toxicity for this species and provides critical data for oil spill modeling. More studies are needed so oil spill models can be appropriately calibrated and to improve their predictive ability. Environ Toxicol Chem 2023;42:2389-2399. © 2023 SETAC.

A novel method for quantifying the attractiveness of lobster trap baits

We developed a new method for quantifying the attractiveness of bait in traps used for crustacean fisheries by using accelerometers in bait containers to assess the amount of time animals spend interacting with the baits. We validated our approach in the laboratory by using time-lapse video recordings to verify that the accelerometry data accurately reflected when, and how much, American lobsters (Homarus americanus) interacted with bait. We then conducted a field experiment comparing traps baited with traditional herring, crushed green crabs (Carcinus maenas), or an inert control. We found that during 48-h trap sets, the number of minutes in which the accelerometers recorded movements of the bait bags was correlated with lobster catch. Although the traps baited with herring did not catch significantly more lobsters than traps baited with crushed green crabs, the accelerometer data revealed differences in bait attractiveness over time. Lobsters interacted less with the green crab bait on the second day of the set, while no such decline was observed with the herring bait. This technique is inexpensive, easy to use, and the data obtained can be more rapidly analyzed than the video data traditionally used for these types of studies, making it well suited for future work on bait choice and attractiveness.

Changes in bacterial communities in chilled American lobster (Homarus americanus) tissues following mortality

Studies evaluating bacteria growing on dead American lobster (Homarus americanus) are typically based on a single observation of the post-mortem period. In this study, seventy-five lobsters were euthanized to evaluate changes in microbiological composition between sexes, and in gut, tail, and claw tissues over a 4-day period under chilled (4 °C) storage. The hygienic quality of meat decreased over the storage period but remained acceptable (<6 log CFU/g). Metagenomic analysis showed alpha and beta diversity differed by tissue type throughout storage time. Photobacterium spp. Were the primary spoilage bacteria identified in gut (49%) and tail (89%) but were less abundant in the claw (11%). Photobacterium spp. Abundance were unchanged in the gut over the sampling period, whereas their proportion increased in the tail (62%) and claw (32%) over the sampling period. Unlike other studies, Photobacterium phosphoreum was the predominant species detected. The detection of bacteria not previously reported in American lobster suggest there could be an association between the microbiota in lobster tissues with their diet and/or habitat, and these factors could influence the spoilage bacteria inhabiting these tissues. Findings identify an opportunity to recover tail and claw meat from dead lobsters with a quality acceptable for human consumption.

Gaps and Challenges in Harnessing the Benefits and Opportunities of Indigenous Certification for a Sustainable Communal Commercial Lobster Fishery.

The Marshall Decision of Canada's Supreme Court inspired the Mi'kmaq in the 1700s regarding recognizing fishing rights to the Mi'kmaq communities. Despite this recognition, the Mi'kmaq communities did not have access to commercial fisheries due to the denial of absolute recognition of territories and rights and underrepresentation and participation in resource allocation, governance, and decision-making processes. A potential approach to these issues is the development of third-party Indigenous community-based sustainability certification standards for the American lobster (Homarus americanus) commercial fishery of Nova Scotia by Mi'kmaq communities. An Indigenous certification is a market-based tool that focuses on a holistic approach to the sustainability of the resource, followed by independent accreditations and standards. This study identifies the gaps, challenges, and opportunities of Indigenous-based certifications for the American lobster commercial fishery. We adopt a participatory approach to conventional policy analysis and perform a secondary analysis of existing legal and scientific resources to glean valuable information for supporting the establishment of an Indigenous certification for the American lobster. Certification could provide benefits such as increased control over fisheries management, governance, rights, and socioeconomic interest, building capacity for Mi'kmaq communities, and improving stakeholder relationships. However, there are issues with the entry points of certification for Indigenous peoples related primarily to the dominant actors in accreditation. This study will support further research and engagement of the Mi'kmaq people toward developing an Indigenous certification scheme.

Spatial dynamics of Maine lobster landings in a changing coastal system

Continued warming of oceans has caused global shifts in marine species distributions. This can result in changes in the spatial distribution of landings and have distributional impacts on marine resource-dependent communities. We evaluated the spatial dynamics of American lobster (Homarus americanus) landings in coastal Maine, which supports one of the most valuable U.S. fisheries. We coupled a bioclimate envelope model and a generalized additive model to project spatial dynamics of lobster landings under possible climate scenarios. This coupled model was then used to forecast future lobster habitat suitability based on IPCC RCP climate scenarios and predict distributions of fishery landings from this projected lobster habitat suitability. The historical spatial distribution of fishery landings shows the highest proportional landings in Maine’s Southern (southwest) regions. The current distribution of landings shows higher proportional landings in Downeast (northeast) regions with the highest proportional landings in Midcoast (middle) regions. Our results suggest that while the proportion of landings in each zone will remain stable, changes in habitat suitability in the spring and fall will reduce total landings. Future habitat suitability is projected to decrease in spring but increase in fall in Downeast areas. Downeast landings are projected to decrease in the next 30 years, then increase over the subsequent 80 years, depending on RCP scenarios and abundance regimes. Midcoast landings are projected to decrease while Southcoast landings are expected to stay constant. This study develops an approach to link climate change effects to fishery landings. These findings have long-term implications for sustainable, localized management of the Maine lobster fishery in a changing climate.

Evaluating the use of side scan sonar for improved detection and targeted retrieval of abandoned, lost, or otherwise discarded fishing gear

Abandoned, lost, or otherwise discarded fishing gear (ALDFG) has surfaced as a significant conservation issue that continues to compromise the economic, social, and ecological aspects of the marine environment. To alleviate these concerns, methods of lost gear detection at the seabed can be applied to increase the precision of derelict gear retrieval and potentially improve the likelihood of success. Targeted in Canada's most productive American lobster (Homarus americanus) fishing area, a “hotspot” analysis was performed by mapping the density of reported lost gear at a 3 km × 3 km grid resolution. The hotspot analysis was used to target the collection of 27 side scan sonar (SSS) transects in Lobster Fishing Area (LFA) 34 over a 12-day survey period in Clark's Harbour, Nova Scotia, to evaluate the benefits of gear detection in large-scale retrieval missions. Following a comprehensive review of the SSS data post-processing, 114 potential ALDFG targets were visually identified, and only one item was confirmed retrieved. Despite this, a large volume of ALDFG was retrieved in areas where there was no SSS coverage based on fisher's local knowledge. The findings from this study demonstrate that retrieval of ALDFG based on SSS data can be difficult due to limitations of retrieval methods used, and that costs of SSS data acquisition may prohibit widescale use of this technology on an annual basis in spatially extensive fishing areas. Nonetheless, the use of SSS to identify ALDFG is recommended at smaller geographic scales in areas where the benthic environment may be sensitive. Although the use of fisher's local knowledge was not evaluated in this study, where the impacts of grappling for ALDFG are considered minimal, local knowledge can be extremely effective in the removal of lost fishing gear and other debris from the benthic environment.

How Might Climate Change Affect American Lobsters?

Climate change is likely to have a dramatic impact on many animals, including American lobsters (Homarus americanus). Lobsters are very sensitive to water temperature, and they will move to avoid water that is too warm or too cold. While this behavior has served them well for 1,000’s of years, as the oceans warm up, they might seek new habitats, which might disrupt aspects of their life cycle and lead to a decline in their numbers. In this article, we aim to explain some facts about American lobsters and tell you about several ways that climate change might have an impact on these fascinating and valuable creatures.

Small effect sizes are achievable in offshore wind monitoring surveys

Abstract Understanding the prospective environmental impacts of offshore wind energy development requires monitoring that allows for adequate testing of conditions for comparison of unimpacted vs. impacted states. A critical component when designing impact studies is determining the required sampling needed to statistically measure a difference between before and after states in the system, which is often challenging because there are little observational data available for the system of interest at the proper spatiotemporal scales. Here, we present the survey design with power and effect size analyses that were used to design a before-after gradient survey to assess American lobster impacts from an offshore wind submarine cable installation in coastal United States waters. By leveraging long-term monitoring data collected from a random-stratified sampling design survey, a gradient survey testing for effects on lobster at distance intervals from the cable using similar sampling methods was developed. Generalized linear mixed models were employed to determine the needed sampling frequency to assess varied catch-per-unit-effort impacts. We present the survey design and our findings from the power analyses to serve as an example of methodology for designing before and after impact surveys for offshore wind energy, and how preexisting data may be used to do so.

Bycatch in northeast Atlantic lobster and crab pot fisheries (Irish Sea, Celtic Sea and Bristol Channel)

Bycatch in valuable NE Atlantic baited ‘pot’ fisheries for lobster Homarus gammarus and edible crab Cancer pagurus has not been well documented, potentially limiting evidence-based management. Using onboard observers supplemented by fishers’ ecological knowledge (FEK) we characterised bycatch of fish and larger invertebrates in 10,741 pot hauls around the coast of Wales, UK, over 4 years in all seasons. A total of 1529 fish from 30 species, and around 15 species of invertebrate, were recorded. Bycatch abundance varied seasonally and spatially and was dominated by eight common and widespread taxa comprising six ‘core’ fish (two catsharks: bullhuss (Scyliorhinus stellaris) and smallspotted catshark (S. canicula); ballan wrasse Labrus bergylta, sea scorpions (Myoxocephalus scorpius &Taurulus bubalis combined), three-bearded rockling Gaidropsarus vulgaris, conger eel Conger conger, together 86% of fish abundance), velvet swimming crab Necora puber and spider crab Maja brachydactyla. Commercially important fish species were only caught in low numbers (3.0% of all fish), with cod Gadus morhua the most frequent (1.8% of all fish). Only two species of conservation interest were recorded: the large catshark Scyliorhinus stellaris which is locally abundant (assessed by the IUCN Red List of Threatened Species as ‘Near Threatened’ and ‘Vulnerable to extinction’ at European and global scales respectively), and a single legally retained spiny lobster Palinurus elephas. Retention or live release status was recorded for nearly all (96%) of the core fish individuals and varied widely with taxa: sea scorpions (never retained), Scyliorhinus stellaris (13% retained), smallspotted catshark, three-bearded rockling, conger eel (44–59% retained), with ballan wrasse having the highest retention (90% of 242 individuals; average of 5.5 individuals retained per trip when present). Observed high spider crab abundance combined with FEK of previous absence or scarcity suggest that this species has increased in northwards range and abundance in recent decades, possibly because of warming seas. No incidents of in-pot mammal or bird entrapment were recorded. The retention of fish for bait is not currently acknowledged in consumer advice or landings data. Possible effects of bait retention on populations of data-poor species which may be vulnerable to overexploitation (e.g., long-lived ballan wrasse) and coastal ecosystems are unknown and warrant further research.

Lobster Position Estimation Using YOLOv7 for Potential Guidance of FANUC Robotic Arm in American Lobster Processing

The American lobster (Homarus americanus) is the most valuable seafood on Canada’s Atlantic coast, generating over CAD 800 million in export revenue alone for New Brunswick. However, labor shortages plague the lobster industry, and lobsters must be processed quickly to maintain food safety and quality assurance standards. This paper proposes a lobster estimation orientation approach using a convolutional neural network model, with the aim of guiding the FANUC LR Mate 200 iD robotic arm for lobster manipulation. To validate this technique, four state-of-the-art object detection algorithms were evaluated on an American lobster images dataset: YOLOv7, YOLOv7-tiny, YOLOV4, and YOLOv3. In comparison to other versions, YOLOv7 demonstrated a superior performance with an F1-score of 95.2%, a mean average precision (mAP) of 95.3%, a recall rate of 95.1%, and 111 frames per second (fps). Object detection models were deployed on the NVIDIA Jetson Xavier NX, with YOLOv7-tiny achieving the highest fps rate of 25.6 on this platform. Due to its outstanding performance, YOLOv7 was selected for developing lobster orientation estimation. This approach has the potential to improve efficiency in lobster processing and address the challenges faced by the industry, including labor shortages and compliance with food safety and quality standards.

Assessing the impact of environmental variability on harvest in a heterogeneous fishery: a case study of the Canadian lobster fishery

ABSTRACT Global fisheries face significant challenges in the coming years due to climate change. Understanding and anticipating the impacts of climate change is a necessity for implementing appropriate fisheries management. This study uses a panel dataset of individual fishing vessels to examine how variation in ocean temperature affects fish harvest. Using the American lobster (Homarus americanus) fishery in the Maritimes region of Canada as a case study, this paper employs a generalised linear mixed model (GLMM) taking into account heterogeneity amongst fishers, gear, vessels, and fishing areas. The GLMM is found to have better performance and estimations when compared against alternative specifications. As expected, a significant and positive relationship was found, further contributing to the existing evidence of warming impacts on the lobster fishery. The implications of this study are twofold: first, it provides further evidence that environmental change does have a significant positive impact on harvest. This information should be considered by fishing industry and fisheries authorities when implementing appropriate adaptive management strategies and measures in their decision making. Second, it illustrates that allowing for mixed-effects using GLMMs is a valuable empirical tool when dealing with hierarchical data structures.