RESUMO
The American lobster (Homarus americanus) is an economically important species in the western Atlantic and its climate-driven range shift northward along the east coast of the United States is well documented. The thermal tolerance of lab-reared postlarvae of this species has been extensively investigated to better understand settlement and recruitment dynamics. However, there have been few studies focused on wild-caught postlarvae, and even fewer that have analyzed lab-rearing conditions in context of diet. In this study, we investigated gene transcriptional changes in postlarvae caught in the wild, as well as postlarvae reared in the laboratory on a brine shrimp diet or a wild-sourced zooplankton diet. We found between wild-caught and brine shrimp-reared larvae 3,682 differentially expressed genes, and between wild and zooplankton-reared postlarvae 3,939 differentially expressed genes. Between the two lab-reared groups fed different diets 2,603 genes were differentially expressed. We also exposed individuals in all rearing groups to chronic temperature treatments of 8°C and 26°C and found that both temperature extremes elicit 68-95% fewer transcriptional changes in wild postlarvae compared to either lab-reared group. In wild postlarvae, we identified differential expression of transcripts within the FoxO signaling pathway, a signaling pathway with a central role in cellular physiology, as potential molecular markers for cold tolerance in the American lobster. These findings contextualize the current literature on lab-reared postlarvae as containing conservative estimates for in situ organisms and can be used to inform population distribution modeling efforts. They also provide evidence for the need to adjust lab-rearing techniques or source wild larval crustaceans to augment studies of larval biology.
Assuntos
Nephropidae , Animais , Nephropidae/genética , Larva/genética , Larva/crescimento & desenvolvimento , Temperatura , Transcriptoma , Artemia/genética , Zooplâncton/genética , Regulação da Expressão Gênica , DietaRESUMO
The biology of extinct animals is usually reconstructed from external morphological characters and comparison with present-day analogues. Internal soft organs are very rarely preserved in fossils and require high-tech approaches for visualization. Here, we report the internal anatomy of a female and male of the ~ 162 Myr-old lobster Eryma ventrosum from the Jurassic La Voulte-sur-Rhône Konservat-Lagerstätte in France using X-ray synchrotron tomography. The Erymidae is an extinct, species-rich, widespread and ecologically important Mesozoic family of decapod crustaceans. Our investigation revealed the anatomy of the locomotory, respiratory, circulatory, excretory, digestive, nervous and sensory, and reproductive systems at a resolution resembling low-magnification histology. Particularly notable is the detailed preservation of the small brain and the fragile hepatopancreas, the main metabolic organ of decapods that decays rapidly post-mortem. The remarkable preservation shows that the internal anatomy of Eryma ventrosum is closer to that of Nephropidae (clawed lobsters) than Astacidae (freshwater crayfish), their closest living relatives based on skeletal morphology. The microanatomy of the gonads and hepatopancreas indicates that the two specimens investigated were a young, well-nourished female and male prior to sexual maturity. The analysis of the soft anatomy reveals remarkable conservatism over 160 Myr and offers new insights into feeding, reproduction, life history and lifestyle of an important component of the macrozoobenthos of Middle Jurassic seas.
Assuntos
Fósseis , Animais , Feminino , Fósseis/anatomia & histologia , Masculino , Decápodes/anatomia & histologia , França , Nephropidae/anatomia & histologiaRESUMO
In contrast to abiotically formed carbonates, biogenetic carbonates have been observed to be nanocomposite, organo-mineral structures, the basic build-blocks of which are particles of quasi-uniform size (10-100 nm) organized into complex higher-order hierarchical structures, typically with highly controlled crystal-axis alignments. Some of these characteristics serve as criteria for inferring a biological origin and the state of preservation of fossil carbonate materials, and to determine whether the biomineralization process was biologically induced or controlled. Here we show that a calcium storage structure formed by the American lobster, a gastrolith initially consisting of amorphous calcium carbonate (ACC) and amorphous calcium phosphate (ACP), post-mortem can crystallize into (thus secondary) calcite with structural properties strongly influenced by the inherited organic matrix. This secondary calcite meets many structural criteria for biominerals (thus called the biomorphic calcite), but differs in trace element distributions (e.g., P and Mg). Such observations refine the capability to determine whether a fossil carbonates can be attributed to biogenic processes, with implications for the record of life on Earth and other terrestrial planets.
Assuntos
Carbonato de Cálcio , Cristalização , Fósseis , Carbonato de Cálcio/química , Carbonato de Cálcio/metabolismo , Animais , Fosfatos de Cálcio/química , Fosfatos de Cálcio/metabolismo , Nephropidae/metabolismo , Nephropidae/química , BiomineralizaçãoRESUMO
Cyanobacteria produce neurotoxic non-protein amino acids (NPAAs) that accumulate in ecosystems and food webs. American lobsters (Homarus americanus H. Milne-Edwards) are one of the most valuable seafood industries in Canada with exports valued at > $2 billion. Two previous studies have assessed the occurrence of ß-N-methylamino-L-alanine (BMAA) in a small number of lobster tissues but a complete study has not previously been undertaken. We measured NPAAs in eyeballs, brain, legs, claws, tails, and eggs of 4 lobsters per year for the 2021 and 2022 harvests. Our study included 4 male and 4 female lobsters. We detected BMAA and its isomers, N-(2-aminoethyl)glycine (AEG), 2,4-diaminobutyric acid (DAB) and ß-aminomethyl-L-alanine (BAMA) by a fully validated reverse phase chromatography-tandem mass spectrometry method. We quantified BMAA, DAB, AEG and BAMA in all of the lobster tissues. Our quantification data varied by individual lobster, sex and collection year. Significantly more BMAA was quantified in lobsters harvested in 2021 than 2022. Interestingly, more BAMA was quantified in lobsters harvested in 2022 than 2021. Monitoring of lobster harvests for cyanobacterial neurotoxins when harmful algal bloom events occur could mitigate risks to human health.
Assuntos
Diamino Aminoácidos , Decápodes , Síndromes Neurotóxicas , Animais , Masculino , Feminino , Humanos , Nephropidae/metabolismo , Ecossistema , Neurotoxinas/toxicidade , Diamino Aminoácidos/metabolismo , Alimentos Marinhos/análise , Decápodes/metabolismo , beta-AlaninaRESUMO
The American lobster, Homarus americanus, is not only of considerable economic importance but has also emerged as a premier model organism in neuroscience research. Neuropeptides, an important class of cell-to-cell signaling molecules, play crucial roles in a wide array of physiological and psychological processes. Leveraging the recently sequenced high-quality draft genome of the American lobster, our study sought to profile the neuropeptidome of this model organism. Employing advanced mass spectrometry techniques, we identified 24 neuropeptide precursors and 101 unique mature neuropeptides in Homarus americanus. Intriguingly, 67 of these neuropeptides were discovered for the first time. Our findings provide a comprehensive overview of the peptidomic attributes of the lobster's nervous system and highlight the tissue-specific distribution of these neuropeptides. Collectively, this research not only enriches our understanding of the neuronal complexities of the American lobster but also lays a foundation for future investigations into the functional roles that these peptides play in crustacean species. The mass spectrometry data have been deposited in the PRIDE repository with the identifier PXD047230.
Assuntos
Sequência de Aminoácidos , Nephropidae , Neuropeptídeos , Proteômica , Animais , Nephropidae/metabolismo , Neuropeptídeos/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/análise , Proteômica/métodos , Espectrometria de Massas , Dados de Sequência MolecularRESUMO
The potential for oil spills poses a threat to marine organisms, the toxicity of which has been attributed primarily to polycyclic aromatic compounds (PACs). Predictive tools such as the target lipid model (TLM) have been developed to forecast and assess these risks. The aim of the present study was to characterize the cardiotoxicity of 10 structurally diverse PACs in American lobster (Homarus americanus) larvae by assessing heart rate following a 48 h exposure in a passive dosing system, and subsequently use the TLM framework to calculate a critical target lipid body burden (CTLBB) for bradycardia. Exposure to 8 of the 10 PACs resulted in concentration-dependent bradycardia, with phenanthrene causing the greatest effect. The TLM was able to effectively characterize bradycardia in American lobsters, and the cardiotoxic CTLBB value determined in this study is among the most sensitive endpoints included in the CTLBB database. This study is one of the first to apply the TLM to a cardiac endpoint and will improve predictive models for assessing sublethal impacts of oil spills on American lobster populations.
Assuntos
Compostos Policíclicos , Poluentes Químicos da Água , Animais , Nephropidae , Bradicardia , Larva , Poluentes Químicos da Água/toxicidade , LipídeosRESUMO
The aim of the present study was to determine the levels of acetylcholinesterase (AChE) activity in the tail muscle tissue of wild populations of Nephrops norvegicus from the Northern Adriatic, and correlate it to body size, seasons, sex and the content of mercury, arsenic, cadmium, lead and copper. The animals of both sexes were collected in spring and autumn from two relatively distant fishing grounds. A marked variability of muscle AChE activity was found (0.49 to 11.22 nmol/min/mg prot.), displaying the opposite seasonal trend between two sampling sites. Small, but significant negative correlation has been found between AChE activity and carapace length (rs = - 0.35, p < 0.05). Data reported here provide an essential baseline for future studies of neurotoxicity in crustaceans. The study highlights the necessity for continuous monitoring of potentially toxic metals in edible marine species to avoid possible repercussions of seafood consumption on human health.
Assuntos
Decápodes , Nephropidae , Feminino , Masculino , Humanos , Animais , Nephropidae/fisiologia , Acetilcolinesterase , Estações do Ano , Metais , Alimentos Marinhos , Músculos , Tamanho Corporal , NoruegaRESUMO
Length-weight relationships (LWR) and relative condition factor were described for species of deep-water crustaceans caught with bottom trawls in a depth range between 150 and 535 m during August and December of 2009, and March and May of 2010 in the Colombian Caribbean Sea. A linear regression was performed using the logarithmically transformed data to calculate the a and b coefficients of the LWR for 22 crustacean species corresponding to 13 families and 19 genera and three types of crustaceans (shrimp, crab, lobster). Six crustacean species showed a maximum total length greater than that reported in SeaLifeBase: Garymunida longipes (77.00 mm), Eunephrops bairdii (220.00 mm), Metanephrops binghami (197.46 mm), Penaeopsis serrata (149.00 mm), Polycheles typhlops (196.27 mm) and Pleoticus robustus (240.00 mm). A total of 11 species (50.0%) exhibited isometric growth, five species (22.7%) negative allometric and six species (27.3%) positive allometric. This study shows the first estimates of LWR for 12 species of deep-water crustaceans in the Colombian Caribbean Sea. We demonstrate for the first time that the growth parameters (intercept and slope) of the LWR varying significantly as a function of the body shape of crabs, lobsters and shrimps in deep-water crustaceans.
Assuntos
Braquiúros , Decápodes , Animais , Região do Caribe , Colômbia , Nephropidae , Somatotipos , ÁguaRESUMO
BACKGROUND: The processing of the three major crustaceans (shrimp, lobster, and crab) is associated with inevitable by-products, high waste disposal costs, environmental and human health issues, loss of multiple biomaterials (chitin, protein hydrolysates, lipids, astaxanthin and minerals). Nowadays, these bioresources are underutilized owing to the lack of effective and standardized technologies to convert these materials into valued industrial forms. AIM OF REVIEW: This review aims to provide a holistic overview of the various bioactive ingredients and applications within major crustaceans by-products. This review aims to compare various extraction methods in crustaceans by-products, which will aid identify a more workable platform to minimize waste disposal and maximize its value for best valorization practices. KEY SCIENTIFIC CONCEPTS OF REVIEW: The fully integrated applications (agriculture, food, cosmetics, pharmaceuticals, paper industries, etc.) of multiple biomaterials from crustaceans by-products are presented. The pros and cons of the various extraction methods, including chemical (acid and alkali), bioprocesses (enzymatic or fermentation), physical (microwave, ultrasound, hot water and carbonic acid process), solvent (ionic liquids, deep eutectic solvents, EDTA) and electrochemistry are detailed. The rapid development of corresponding biotechnological attempts present a simple, fast, effective, clean, and controllable bioprocess for the comprehensive utilization of crustacean waste that has yet to be applied at an industrial level. One feasible way for best valorization practices is to combine innovative extraction techniques with industrially applicable technologies to efficiently recover these valuable components.
Assuntos
Braquiúros , Decápodes , Humanos , Animais , Nephropidae , Alimentos Marinhos , Materiais BiocompatíveisRESUMO
The hydroxyapatite (HAp; Ca10 (PO4 )6 (OH)2 )) has good biocompatibility, bioactivity, and osteoconductivity as a bone implant because the main inorganic mineral of human bone is HAp. The use of scaffold HAp from biogenic resources that contain high calcium and polymer as a pore forming agent to support bone growth is a longstanding area of interest. In this study, porous scaffolds based on HAp were synthesized from sand lobster (SL; Panulirus homarus) shells as a source of calcium using the porogen leaching method with polyethylene oxide (PEO) and chitosan (Chs) as polymeric porogen. The present study aims to synthesize HAp derived from SL shells and evaluate the effect variations of PEO on the physicochemical properties of the scaffold and cytotoxicity in cell viability assay. Briefly, the SL shell powder was calcinated with temperature variations of 600°C, 800°C, and 1000°C for 6 h. Based on the characterization, it was shown that 1000°C was the optimum calcination temperature for SL shells to synthesize HAp using the precipitation method. The characterization results of HAp using energy dispersive x-ray (EDX) revealed that the molar ratio of Ca/P was 1.67. The Fourier transform infrared (FTIR) and x-ray diffractometer (XRD) spectral patterns indicated that HAp had been successfully synthesized with minor ß-tricalcium phosphate (ß-TCP), a calcium phosphate with high biocompatibility. Porous scaffolds were synthesized by varying the concentration of PEO at 0, 5, 10, and 15 wt %. Physicochemical analysis revealed that a higher concentration of PEO affected decreased crystallinity and compressive strength, but on the other hand, the porosity and pore sizes increased. Based on the physicochemical analysis, the synthesized porous scaffold showed that HAp/PEO/Chs 15 wt % had the most potential as a scaffold for biomedical applications. MTT Assay, after 24 h incubation, revealed that the scaffold was safe for use at low concentrations on the MC3T3E1 osteoblast cells, with a percentage of cell viability of 83.23 ± 3.18% at 23.4375 µg/mL. Although the cell viability decreased at higher concentrations, the HAp/PEO/Chs 15 wt % scaffold was cytocompatible with the cells. Thus, in the present study, HAp/PEO/Chs 15 wt % was the best scaffold based on pore structure, chemical composition, mechanical and crystalographic properties and cell viability.
Assuntos
Quitosana , Palinuridae , Animais , Humanos , Engenharia Tecidual/métodos , Durapatita/farmacologia , Durapatita/química , Quitosana/química , Porosidade , Alicerces Teciduais/química , Nephropidae , Areia , Polietilenoglicóis , Cálcio , Polímeros , Materiais Biocompatíveis/químicaRESUMO
Chitin extraction from the shells of American lobsters (Homarus americanus) was optimized through the use of response surface methodology (RSM). The demineralization step was optimized to minimize the ash content of shell samples and the deproteination step was optimized to minimize the protein content of the chitin product. At a laboratory scale, one set of optimized conditions for the demineralization step was 7.35 % w/w acetic acid at a 40 mL/g of powdered lobster shell ratio for 15 min; this lowered the ash content from 39.62 % to 0.41 ± 0.08 %. A set of optimized conditions for the deproteination step at a similar scale was 4 % w/w sodium hydroxide at a 43 mL/g demineralized shell ratio heated to 95 °C for 83 min. These conditions were indicated to entirely remove protein from the resultant chitin. Average yields under optimized conditions were 23.43 ± 1.75 % for demineralization and 30.33 ± 0.02 % for deproteination, though a demineralization reaction with larger biomass input had a higher yield at 40.31 %.
Assuntos
Quitina , Decápodes , Animais , Quitina/química , Nephropidae , Decápodes/química , Exoesqueleto/químicaRESUMO
Plastic waste from the fishing industry, particularly lobster trap identification tags from the USA and Canada, poses a significant threat to marine ecosystems due to its resilience. This study unveils a novel link between North American fisheries and the appearance of these plastic tags in Macaronesia. Collected in the Azores and Canary Islands, these tags offer a unique insight into the sources and spatio-temporal scales of marine plastic pollution. Ocean model data indicates the Labrador Current and Gulf Stream as key forces transporting these tags. Virtual particle simulations show a small fraction reaching Macaronesia (4.12 % in the Azores, 0.76 % in the Canary Islands), suggesting real ocean drift. The Azores, with more collected tags, are more susceptible, and tags can reach Macaronesia in under a year. These findings underscore the urgency of better waste management and emphasize the role of citizen science in monitoring and combating marine pollution.
Assuntos
Decápodes , Nephropidae , Animais , Pesqueiros , Ecossistema , Monitoramento Ambiental , Canadá , Plásticos , Resíduos/análiseRESUMO
A comprehensive molecular analysis of the deep-sea blind lobsters of the family Polychelidae, often referred to as "living fossils", is conducted based on all six modern genera and 27 of the 38 extant species. Using six genetic markers from both mitochondrial and nuclear genomes, the molecular phylogenetic results differ considerably from previous morphological analyses and reveal the genera Polycheles and Pentacheles to be para- or polyphyletic. As the splitting of Polycheles has strong support from both molecular and morphological data, two new genera, Dianecheles and Neopolycheles, are erected for those species excluded from the clade containing the type species of Polycheles. The pattern of polyphyly of Pentacheles, however, is not robustly resolved, so it is retained as a single genus. Fossil evidence suggests that fossil polychelids inhabited deep-sea environments as early as the Early to Middle Jurassic, demonstrating the enduring adaptation of extant polychelid species to the deep-sea. Time-calibrated phylogeny suggested that modern polychelids probably had an Atlantic origin during the Jurassic period. Since their emergence, this ancient lobster group has continued to diversify, particularly in the West Pacific, and has colonized the abyssal zone, with the deepest genus, Willemoesia, representing the more 'derived' members among extant polychelids. Differences in eye reduction among extant polychelid genera highlight the necessity for ongoing investigations to ascertain the relative degree of functionality of their eyes, if they indeed retain any function.
Assuntos
Decápodes , Fósseis , Animais , Filogenia , Nephropidae , Decápodes/genéticaRESUMO
Food allergies are a growing public health problem with recent estimates of 10% of the US population affected by this immunologic disease. The quality of life is greatly impaired in food allergic individuals and their caregivers due to constant vigilance and fear of accidental exposure. Shellfish allergies are of particular concern because their prevalence has increased over the past 15 years, now affecting an estimated 3% of the adult population and 1.3% of children in the USA. Additionally, they are rarely outgrown, can result in fatal reactions, and there are no FDA-approved therapies for shellfish allergies. Reactions to one type of shellfish, crustaceans (shrimp, lobster, and crab), can be especially severe. The major crustacean allergens are highly conserved across species, resulting in high cross-reactivity of IgE between shrimp, lobster, and crab in allergic individuals. To develop novel therapies for shellfish allergies, preclinical mouse models are required. In this chapter, we present detailed methodology to induce shrimp allergy in CC027 mice. Once sensitized, mice produce shrimp-specific IgE, that is cross-reactive with lobster and crab, and experience anaphylaxis upon shrimp challenge. This model can be used to further investigate mechanisms of sensitization and preclinical testing of therapies.
Assuntos
Anafilaxia , Braquiúros , Decápodes , Hipersensibilidade a Frutos do Mar , Humanos , Adulto , Criança , Animais , Camundongos , Nephropidae , Qualidade de Vida , Alimentos Marinhos , Modelos Animais de Doenças , Imunoglobulina ERESUMO
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.
Assuntos
Nephropidae , Reprodução , Animais , Feminino , Ecossistema , Pesqueiros , Nova Escócia , MasculinoRESUMO
Norwegian lobster, Nephrops norvegicus, are a generalist scavenger and predator capable of short foraging excursions but can also suspension feed. Existing knowledge about their diet relies on a combination of methods including morphology-based stomach content analysis and stable isotopes, which often lack the resolution to distinguish prey items to species level particularly in species that thoroughly masticate their prey. DNA metabarcoding overcomes many of the challenges associated with traditional methods and it is an attractive approach to study the dietary profiles of animals. Here, we present the diet of the commercially valuable Nephrops norvegicus using DNA metabarcoding of gut contents. Despite difficulties associated with host amplification, our cytochrome oxidase I (COI) molecular assay successfully achieves higher resolution information than traditional approaches. We detected taxa that were likely consumed during different feeding strategies. Dinoflagellata, Chlorophyta and Bacillariophyta accounted for almost 50% of the prey items consumed, and are associated with suspension feeding, while fish with high fisheries discard rates were detected which are linked to active foraging. In addition, we were able to characterise biodiversity patterns by considering Nephrops as natural samplers, as well as detecting parasitic dinoflagellates (e.g., Hematodinium sp.), which are known to influence burrow related behaviour in infected individuals in over 50% of the samples. The metabarcoding data presented here greatly enhances a better understanding of a species' ecological role and could be applied as a routine procedure in future studies for proper consideration in the management and decision-making of fisheries.
Assuntos
Decápodes , Nephropidae , Animais , Código de Barras de DNA Taxonômico , Alimentos Marinhos , Peixes , DietaRESUMO
Intensive research on the effectiveness of chemoattractants has been widely explored to improve the feed qualities in expanding crustacean farming. Taste preferences in slipper lobster remained unknown despite their significant contribution to the lobster fisheries. Chemoattractants allow better performance in aquaculture species by increasing food attractiveness and palatability. Amino acids (AA) have been leading in previous research on crustacean feeding behavior. Given that slipper lobster possesses chemoreceptors to detect and orient towards food, this study investigated an approach to identify the AA with the most potent chemoattractant in eliciting a response from slipper lobster. Behavioral assays were performed to evaluate the responses of slipper lobster Thenus orientalis (carapace length, 52.34 ± 1.52 mm) on 15 crystalline AA and three derivatives of AA (DAA) at three concentrations between 10-1 and 10-3 M as test substances (TS). Meretrix sp. extract was used as a positive control and clean filtered seawater as a negative control. The behavioral responses of 14 T. orientalis were evaluated based on their antennular flicking rate, third maxillipeds activity, and substrate probing by the pereiopods. T. orientalis responded to the solutions of single AA down to a concentration of 10-3 M, excluding histidine and serine. The behavioral activity displayed by T. orientalis increased with the TS concentrations. L-glutamic acid monosodium salt monohydrate, betaine, and glycine solutions elicited the most behavioral responses, whereas histidine exhibited the lowest behavioral responses. Conclusively, L-glutamic acid monosodium salt monohydrate, betaine, and glycine can be potential chemoattractants for T. orientalis.
Assuntos
Aminoácidos , Decápodes , Animais , Aminoácidos/farmacologia , Nephropidae , Ácido Glutâmico , Histidina , Betaína , GlicinaRESUMO
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.
Assuntos
Pesqueiros , Nephropidae , Animais , Humanos , Nova Escócia , CertificaçãoRESUMO
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.