Australian Crayfish Research Articles

Functional morphology and ontogeny of mouthparts and mouth aperture of Panulirus ornatus and Sagmariasus verreauxi: Implications towards formulated feeds development

Development of formulated feed is now a focal point in advancing the aquaculture of spiny lobster species. This study investigated the functional morphology of two spiny lobsters, Panulirus ornatus and Sagmariasus verreauxi, by analysing mouthpart morphology and mouth aperture. The analysis is focussed on determining likely feed preference based on morphology with the aim to provide knowledge for the development of formulated feeds. There is a strong correlation between the mouth aperture being approximately 4.0 and 7.5% of the carapace length of S. verreauxi and P. ornatus juvenile and adult lobsters, respectively. This finding provides knowledge for development of a species-specific tool that could be used in experimental studies to define optimal dimensions of artificial manufactured pellets in relation to the size of the lobster. Differences in mouthpart morphology through ontogeny included increase of calcification and robustness, and this is likely to reflect a different requirement in the texture (softness/hardness) of the pellet as the animals develop. Spines and setation are a prominent feature of the mouthpart morphology and differ between species and during ontogeny. Spines on maxillipeds II and III and crista dentata on maxillipeds III are likely to play an important role in holding and manipulation of feed prior to ingestion. Pellet texture may need to accommodate these differences in species and age specific mouthpart ontogeny. Ontogenetic changes in setation were found, with much richer setation proportionally to the size of mouthpart in first instar juvenile lobsters, which decreases with size increase. Furthermore, species-specific differences indicate function shifts in mouthparts with life stages. This may indicate differences in filter feeding capacity with age and between species, as reported for other decapods. This is unlikely to be of high importance in pellet feeding but may represent an avenue of investigation for first feeds in juveniles. Collectively, the differences during ontogeny and between species suggest that formulated feeds may need to be tailored to species and life stage, particularly regarding pellet dimensions and texture.

Biology, distribution and conservation of a dwarf-group crayfish, Euastacus spinichelatus Morgan, 1997 (Decapoda: Astacidea: Parastacidae), a freshwater crayfish from the Great Dividing Range, New South Wales, Australia

Abstract We present the outcomes of two conservation initiatives, namely ‘The Australian Crayfish’ and ‘Saving the Spinys’ projects, which have substantially contributed to enhancing our understanding of E. spinichelatus concerning its distribution, habitat, biology, and conservation status. We extend the range of E. spinichelatus to encompass the headwater reaches of the Namoi River within the Murray-Darling Basin. The use of molecular taxonomy analyses identified divergent lineages that acted to remove the southeastern tributaries of the Hastings River and the most western tributary of the Manning River from the range of E. spinichelatus. The species has suffered significant population declines in recent years, with it appearing to be highly susceptible to anthropogenic changes, drought and/or high-severity bushfires. Results advocate for the classification of E. spinichelatus as an endangered species, recognizing its distinctive ecological niche and its status as a climate refugee, aiming to protect this rare species from anthropogenic and climate-related challenges. We also present a taxonomic key differentiating E. spinichelatus from other members of Parastacidae in the region.

Discontinuous, biphasic, ontogenetic shifts in the metabolic allometry of aquatic animals?

Several investigations in recent years have reported patterns of discontinuous, biphasic, loglinear variation in the metabolic allometry of aquatic animals. These putative shifts in pattern of allometry have been attributed to changes in the primary site for gas exchange from cutaneous to branchial as animals undergo ontogenetic changes in size, shape, and surface area. Because of the important implications of the earlier research with regard to both physiology and evolution, I re-examined data that purportedly support claims of discontinuous, biphasic allometry in oxygen consumption versus body size of American eels (Anguilla rostrata) and spiny lobsters (Sagmariasus verreauxi). I used ANCOVA to fit three different statistical models to each set of logarithmic transformations and then assessed the fits by Akaike's Information Criterion. The observations for both species were described better by a single straight line fitted to the full distribution than by a biphasic model. Eels, lobsters, and other aquatic animals undergo changes in shape and surface area as they grow, but such changes are not necessarily accompanied by changes in the pattern of metabolic allometry.

The Australian red-clawed crayfish (Cherax quadicarinatus Von Martens 1868) is a promising aquaculture object for the south of the Russian Federation

The paper presents information about a promising aquaculture object for the south of the Russian Federation - the Australian red-clawed crayfish Cherax quadicarinatus Von Martens 1868. A brief description of its biological characteristics, which are the main factor in the development of specific biotechnologies for its commercial cultivation, is given. The main limiting factor in the artificial cultivation of this species is water temperature. The article indicates that for Russian conditions, three possible directions for growing Australian crayfish can be distinguished: in ponds in the southern regions of Russia in natural climatic conditions (summer); in ponds, cages and pools on warm waters of energy facilities in the summer; in closed water supply installations – year-round. A technology has been proposed for combined cultivation of crayfish, in which the production of juveniles is carried out in controlled basin conditions, and the cultivation of commercial products in earthen ponds in warm seasons, when the water temperature corresponds to the biological needs of the species.

Effect of Feed Texture and Dimensions, on Feed Waste Type and Feeding Efficiency in Juvenile Sagmariasus verreauxi

The “messy” feeding behaviour of spiny lobsters remains an obstacle for formulated feed development. This study examined the relationship between feeding efficiency and feed waste by juvenile spiny lobster, Sagmariasus verreauxi, fed different formulated pellet diameters or lengths across two separate experiments. Feed texture (hard and dry pellet, HDP; soft and moist pellet, SMP) was also examined. Juvenile lobsters were fed experimental feeds at 0.5% BW daily over a 6 h duration. The resulting feed waste was categorised as either feeding-related waste (FRW) or non-feeding-related waste (NFRW). For all feed types, the FRW increased with increasing pellet diameter and pellet length. The increase in FRW corresponded with a decrease in NFRW, particularly for HDP, resulting in no difference in total feed waste in any treatment investigated. Thus, even with improved feeding efficiency with small feed dimensions, feed intake was not improved. Feed leaching rate decreased with increasing pellet size, suggesting a more rapid decline in feed attractiveness for smaller pellets. This finding indicates that currently a counteractive interaction exists between pellet size and feed attractiveness and suggests improving attractiveness would further enhance feeding. Future research should aim at optimising feed dimensions simultaneously to support efficient feeding whilst enhancing attraction/gustatory stimulations.

Recommendations for growing young Australian red-clawed crayfish (Cherax quadricarinatus) in industrial conditions

The Australian thermophilic red-clawed crayfish (Cherax quadricarinatus) is characterized by a number of qualities that ensure its effective cultivation in commercial aquaculture. At the same time, the year-round cultivation of this species in natural reservoirs of Russia is limited by the seasonal course of temperatures. In this regard, the cultivation of tropical crayfish in certain periods of life in regulated conditions is a necessary stage of full-cycle technology. In particular, the successful maintenance of ARCC juveniles until they are transferred to natural conditions (after reaching a mass of 5 g) in installations with a controlled temperature regime is due to a number of factors. First of all, this is the planting density, which naturally depends on the area and capacity of installations with a closed water supply cycle, the size, mass and age characteristics of the object. The physiological and biological state of crayfish, the intensity and quality of feeding, and the duration of cultivation play an important role. The purpose of this work is to determine the main technological indicators of growing juveniles Australian red-clawed crayfish in industrial conditions up to 5 g. Data on the results of growing juveniles Australian red-clawed crayfish under controlled temperature conditions showed the main differences in mass indicators and survival of groups of juveniles Australian crayfish depending on the initial average weight, planting density, order of offspring. The terms of growing juveniles up to 5 g have been established, the feed costs for this period have been calculated, the chemical composition of the body of juvenile crayfish has been determined.

Westward range expansion of the eastern rock lobster (Sagmariasus verreauxi) in Australia

Abstract The eastern rock lobster (Sagmariasus verreauxi) inhabits the east coast of Australia from southern Queensland to the South Australian border including Tasmania, with the highest abundances found in New South Wales. Changes in strength, duration, and intensity of the eastern Australian current have expanded the species range southward but until recently, records of the species in western regions of south-eastern Australia were rare. Here, we report the first ever verified records of S. verreauxi in the northern zone rock lobster fishery of South Australia, which are the most westerly records ever documented in terms of overall distribution for this species. We hypothesise that two westward flowing systems, the offshore Flinders current and the inshore coastal current may be possible mechanisms for larval transport.

Non-lethal sampling does not misrepresent trophic level or dietary sources for Sagmariasus verreauxi (eastern rock lobster).

Isotope analysis can be used to investigate the diets of predators based on assimilation of nitrogen and carbon isotopes from prey. Recent work has shown that tissues taken from legs, antennae or abdomen of lobsters can give different indications of diet, but this has never been evaluated for Sagmariasus verreauxi (eastern rock lobster). Work is now needed to prevent erroneous conclusions being drawn about lobster food webs, and undertaking this work could lead to developing non-lethal sampling methodologies. Non-lethal sampling for lobsters is valuable both ethically and for areas of conservation significance such as marine reserves. We evaluated this by dissecting 76 lobsters and comparing δ13 C and δ15 N isotope values in antennae, leg and abdomen tissue from the same individuals ranging from 104 to 137 mm carapace length. Stable isotope values were determined using a Europa EA GSL elemental analyser coupled with Hydra 20-20 Isoprime IRMS. We found the abdomen δ13 C values to be lower than other tissues by 0.3 ± 0.2‰ for antennae tissue and 0.1 ± 0.2‰ δ13 C for leg tissues, whereas for δ15 N, no significant difference between tissues was observed. There was no significant effect of lobster size or sex, though we did observe interactions between month and tissue type, indicating that differences may be seasonal. Importantly, the detected range of isotopic variability between tissues is within the range of uncertainty used for discrimination factors in isotopic Bayesian modelling of 0‰-1.0‰ for δ13 C and 3.0‰-4.0‰ for δ15 N. We show that S. verreauxi can be sampled non-lethally with mathematical corrections applied for δ13 C, whereas any tissue is suitable for δ15 N. Our results indicate that a walking leg is most favourable and would also be the least intrusive for the lobster. The application of non-lethal sampling provides avenues for the contribution of citizen science to understanding lobster food webs and to undertake fieldwork in ecologically sensitive areas such as marine reserves.

Moult cycle staging in decapod crustaceans (Pleocyemata) and the Australian crayfish, Cherax destructor Clark, 1936 (Decapoda, Parastacidae)

Abstract We tabulated decades of published moult stage criteria of Decapoda: Pleocyemata on setogenesis and changes in pleopods, uropods and gastroliths; and reviewed them focusing on the comparative biology of Cherax destructor. We found their staging criteria relatively consistent. For C. destructor, lacking were a comprehensive description with micrographs; a juvenile application; and, known stage duration. Therefore, we developed comprehensive moult staging techniques in juvenile C. destructor using pleopods, antennules and gastroliths. Using pleopod staging, we found C. destructor exhibits anecdysis as a true transition stage (D0), which occupied around half the moult cycle. We successfully applied this method to juvenile and adult marbled crayfish. We report on these suggested novel techniques: moult staging using pleopods: novel in crayfish; moult staging using antennules: novel in decapods; moult staging using gastrolith deposition: novel in C. destructor; and, calculating the gastrolith moult mineralization index using height: novel in decapods.

Metabolic plasticity improves lobster\u2019s resilience to ocean warming but not to climate-driven novel species interactions

Marine species not only suffer from direct effects of warming oceans but also indirectly via the emergence of novel species interactions. While metabolic adjustments can be crucial to improve resilience to warming, it is largely unknown if this improves performance relative to novel competitors. We aimed to identify if spiny lobsters—inhabiting a global warming and species re-distribution hotspot—align their metabolic performance to improve resilience to both warming and novel species interactions. We measured metabolic and escape capacity of two Australian spiny lobsters, resident Jasus edwardsii and the range-shifting Sagmariasus verreauxi, acclimated to current average—(14.0 °C), current summer—(17.5 °C) and projected future summer—(21.5 °C) habitat temperatures. We found that both species decreased their standard metabolic rate with increased acclimation temperature, while sustaining their scope for aerobic metabolism. However, the resident lobster showed reduced anaerobic escape performance at warmer temperatures and failed to match the metabolic capacity of the range-shifting lobster. We conclude that although resident spiny lobsters optimise metabolism in response to seasonal and future temperature changes, they may be unable to physiologically outperform their range-shifting competitors. This highlights the critical importance of exploring direct as well as indirect effects of temperature changes to understand climate change impacts.

Resident lobsters dominate food competition with range-shifting lobsters in an ocean warming hotspot

Species redistributions are one of the most prevalent changes observed in oceans worldwide due to climate change. One of the major challenges is being able to predict temperature-driven changes to species interactions and the outcome of these changes for marine communities due to the complex nature of indirect effects. In the ocean-warming hotspot of south-east Australia, the ranges of many species have shifted poleward. The range of the eastern rock lobster Sagmariasus verreauxi has extended into warming Tasmanian waters inhabited by the resident southern rock lobster Jasus edwardsii, which may lead to increased competitive interactions between the species. Using video monitoring, we investigated how the 2 species compete for food at current (18°C), future (21°C) and future heatwave (24°C) summer temperatures. Behavioural competition occurred in 80% of experiments, during which J. edwardsii won 84% of competitive interactions and showed more aggressive behaviour at all temperatures. This indicates that resident J. edwardsii is not only more dominant in direct food competition than the range-shifting S. verreauxi but, surprisingly, also sustains competitive dominance beyond its physiological thermal optimum under predicted future ocean warming and heatwave scenarios.

ВЕТЕРИНАРНО-САНИТАРНАЯ ХАРАКТЕРИСТИКА АВСТРАЛИЙСКОГО КРАСНОКЛЕШНЕВОГО РАКА

The article raises the issue of veterinary and sanitary cultivation of Australian red-tick crayfish (Cherax quadricarinatus) in artificial conditions. The methods of growing Australian crayfish in aquarium conditions in a closed water supply installation are considered. Hydrochemical, organoleptic and microbiological parameters of water are considered when growing Australian crayfish in artificial conditions.

On the issue of Australian crayfish cultivation in ponds to ensure sustainable aquaculture development

The authors of this article describe the experience of biotechnology for growing Australian crayfish in conditions of pond cultivation in a group of ponds, operating in an intensive mode, used in an isolated area close by a natural water source in the Astrakhan region. In the presented article, research is aimed to clarify the main biotechnological indicators that increase the efficiency of cultivation in pond conditions. The conditions of transportation, the duration of transportation, and the density of crayfish in ponds with an area of 1 hectare have been clarified. The presented food recipe with the specification of the percentage of nutrients as additional feeding, organized when growing in ponds according to the food recipe itself, increases not only the growth rate but also the hemolymph protein concentration, which indirectly proves the satisfactory conditions for keeping aquaculture objects. Monitoring for the biotechnology of growing Australian crayfish in pond conditions: own developed food recipe, biological and physiological testing of key indicators such as hydrochemical indicators of water, hydrobiological indicators of the concentration of, and physiological indicators for determining the so-called biotechnological norm, which will add additional missing information on this aquaculture object.

ГЕМАТОЛОГИЧЕСКИЕ И БИОХИМИЧЕСКИЕ ПОКАЗАТЕЛИ ГЕМОЛИМФЫ АВСТРАЛИЙСКОГО КРАСНОКЛЕШНЕВОГО РАКА

The article describes Australian red claw crayfish, Cherax quadricarinatus, which is currently one of the most promising cultivation targets. However, to increase production volumes, it is necessary to improve cultivation technologies, which should be based on the data of physiological and biochemical parameters. An objective method for monitoring the physiological state 
 of Australian red claw crayfish in the artificial conditions is determining its hematological and biochemical indicators that complement the general characteristics of hemolymph and later define its physiological norm. When giving the objects the compound feed, which the authors produced by their own recipe, there was recorded a high level of total hemolymph protein of 40.8 ± 4.5 g/l. According to the results of biochemical research, the cholesterol content in the hemolymph of Australian crayfish was 3.2 ± 0.6 mmol/l, and the concentration of lipoproteins was 0.8 ± 0.2 g/l (levels within the reference values). When considering the hemogram of hemolymph there were found the dominant types and linear dimensions of native formed elements. The diameter of agranulocytes in Australian freshwater crayfish varied from 85 to 90 μm, semi-granulocytes - from 90 to 95 μm, granulocytes - from 65 to 78 μm, transparent cells differed by greater variability in size, which ranged from 85 to 120 μm. The part of granulocytes in relation to other shaped elements exceeded 50%, for transparent cells it turned out to be above 20%, for semi-granulocytes - about 15% and for agranulocytes - about 5%, which means that the latter form the rarest group. The established ratios are specific for Cherax quadricarinatus, its hemocytic characteristics greatly differs from Astacus leptodactylus, which is the main object of comparative research. The results of comparative analysis of the cellular composition of the hemolymph of the Australian freshwater crayfish Cherax quadricarinatus (Von Martens, 1868) demonstrate the taxonomic specificity of this representative of freshwater aquaculture

Population genomics of the Eastern Rock Lobster,Sagmariasus verreauxi, during spawning stock recovery from over-exploitation

AbstractFisheries are currently under pressure to provide increasing amounts of seafood, causing a growing number of marine stocks to be harvested at unsustainable levels. To ensure marine resources remain sustainable, careful management of biological stocks and their genetic integrity is required. The Eastern Rock Lobster, Sagmariasus verreauxi, is commercially harvested along the New South Wales (NSW) coast of eastern Australia and is managed as a single unit. Due to overfishing, the NSW S. verreauxi stock was severely depleted in the mid-1990s but has since been rebuilding. This study evaluates the population genetic structure, putative local adaptation, and potential of a population bottleneck for NSW S. verreauxi. Using neutral single nucleotide polymorphisms (SNPs), we determined NSW S. verreauxi consist of a single genetic stock, with outlier SNPs detecting weak genetic divergence among offshore locations, and evidence of population bottlenecks at all locations. Our findings (i) confirm a single management unit is appropriate; (ii) can be used as a baseline for future genetic monitoring of NSW S. verreauxi; and (iii) highlights the importance of implementing routine genetic monitoring and collecting temporal samples to understand the full impact of overfishing on a species resilience.

Effect of dietary protein on energy metabolism including protein synthesis in the spiny lobster Sagmariasus verreauxi

This is the first study in an aquatic ectotherm to combine a stoichiometric bioenergetic approach with an endpoint stochastic model to explore dietary macronutrient content. The combination of measuring respiratory gas (O2 and CO2) exchange, nitrogenous (ammonia and urea) excretion, specific dynamic action (SDA), metabolic energy substrate use, and whole-body protein synthesis in spiny lobster, Sagmariasus verreauxi, was examined in relation to dietary protein. Three isoenergetic feeds were formulated with varying crude protein: 40%, 50% and 60%, corresponding to CP40, CP50 and CP60 treatments, respectively. Total CO2 and ammonia excretion, SDA magnitude and coefficient, and protein synthesis in the CP60 treatment were higher compared to the CP40 treatment. These differences demonstrate dietary protein influences post-prandial energy metabolism. Metabolic use of each major energy substrate varied at different post-prandial times, indicating suitable amounts of high-quality protein with major non-protein energy-yielding nutrients, lipid and carbohydrate, are critical for lobsters. The average contribution of protein oxidation was lowest in the CP50 treatment, suggesting mechanisms underlying the most efficient retention of dietary protein and suitable dietary inclusion. This study advances understanding of how deficient and surplus dietary protein affects energy metabolism and provides approaches for fine-scale feed evaluation to support sustainable aquaculture.

Dietary analysis and mesocosm feeding trials confirm the eastern rock lobster (

Worldwide, lobsters are considered important predators of macroalgae-consuming urchin species, but this has not been tested for Australia’s common lobster, the eastern rock lobster (Sagmariasus verreauxi). We predicted that the abundant urchins, the long-spined urchin (Centrostephanus rodgersii) and the short-spined urchin (Heliocidaris erythrogramma), would form substantial components of lobster diets. To test this hypothesis, we examined 115 lobster stomachs from 9 locations and conducted 14 feeding trials, in which lobsters were offered either urchin species. Dissections revealed various stomach items, with detritus (51%), bivalves (34%), gastropods (28%) and algae (26%) occurring more frequently than urchins (19%). Urchin spines were found in 22 lobsters that ranged in size from 91- to 124-mm carapace length, with all individuals containing H. erythrogramma spines and C. rodgersii spines observed only once. During feeding trials, seven urchins were consumed. Four H. erythrogramma were eaten on Day 1, whereas one was not eaten until Day 11. Two C. rodgersii were eaten on Days 2 and 10. Only three of the six lobsters observed to eat urchins ingested spines. Together, these data show that S. verreauxi is a generalist predator that consumes urchins, although, because urchins could be eaten without ingesting spines, future studies are needed to assess the importance of urchins as dietary items for S. verreauxi.

Testing of experimental feed for young Australian red-clawed crayfish that meets its nutritional needs

One of the relatively promising types of world aquaculture is the Australian redclawed crayfish, which is one of the relatively promising objects in warm-water aquaculture. Compared to other farmed crustaceans (shrimps, crabs), Australian crayfish is characterized by a high growth rate and unpretentiousness to the conditions of aging. In the process of cultivation of red-clawed crayfish, industrial granulated feeds developed for other types of hydrobionts (shrimps, fish) are currently used. In the presence of biotechnological standards for growing juveniles and commercial products of red-clawed crayfish, the question remains open about the lack of production of balanced specialized feeds for them. The purpose of this work was to test an experimental feed developed according to its own recipe for young Australian red-clawed crayfish. The main stages of the technology of preparation of the above feed are described. The experimental feed was compared with production dry feed according to the main parameters (qualitative composition, nutritional value, consumer characteristics). Taking into account the nutritional needs of crayfish in the main nutrients (protein, fat, fiber), three types of food were selected: for loricarium catfish, for juvenile sturgeon and experimental. In accordance with them, three variants of the experiment were laid down, where the conditions of maintenance (planting density, temperature and light modes, feeding frequency) were identical, except for differences in the type of feed. During the experiment, the main differences in the size and weight parameters of groups of juvenile Australian crayfish cultured using these feeds were revealed. The necessary conditions for keeping crustaceans in the laboratory and the scheme of their control are described.

Mismatch of thermal optima between performance measures, life stages and species of spiny lobster

In an ocean warming hotspot off south-east Australia, many species have expanded their ranges polewards, including the eastern rock lobster, Sagmariasus verreauxi. This species is likely extending its range via larval advection into Tasmanian coastal waters, which are occupied by the more commercially important southern rock lobster, Jasus edwardsii. Here, thermal tolerances of these lobster species at two life stages were investigated to assess how they may respond to warming ocean temperatures. We found that the pattern, optimum and magnitude of thermal responses differed between performance measures, life stages and species. Sagmariasus verreauxi had a warmer optimal temperature for aerobic scope and escape speed than J. edwardsii. However, J. edwardsii had a higher magnitude of escape speed, indicating higher capacity for escape performance. There were also differences between life stages within species, with the larval stage having higher variation in optimal temperatures between measures than juveniles. This inconsistency in performance optima and magnitude indicates that single performance measures at single life stages are unlikely to accurately predict whole animal performance in terms of life-time survival and fitness. However, combined results of this study suggest that with continued ocean warming, S. verreauxi is likely to continue to extend its distribution polewards and increase in abundance in Tasmania.

The use of stoichiometric bioenergetics to elucidate metabolic energy substrate use and specific dynamic action in cultured juvenile spiny lobsters (Sagmariasus verreauxi) of different nutritional status

Simultaneous measurements of nitrogenous (ammonia and urea) excretion and respiratory gas (O2 and CO2) exchange provide a non-destructive stoichiometric bioenergetic approach to elucidate metabolic energy substrate use which has rarely been used with aquatic ectotherms due to previous difficulties in measuring total CO2 excretion. This study examined metabolic energy substrate use and specific dynamic action (SDA) in cultured spiny lobster, Sagmariasus verreauxi, of different nutritional status. SDA magnitude calculated by stoichiometry was compared to a traditional composite oxycalorific coefficient approach. Protein synthesis can account for a large part of SDA in aquatic ectotherms. This study used a protein synthesis inhibitor cycloheximide to investigate the contribution of cycloheximide-sensitive protein synthesis to SDA and the effect of cycloheximide on nitrogenous and CO2 excretion. Lobsters were subjected to five treatments: 2-day fasted juveniles sham injected with saline (FS treatment); 2-day fasted juveniles injected with cycloheximide (FC treatment); 10-day starved juveniles injected with cycloheximide (SC treatment); post-prandial juveniles fed squid Nototodarus sloanii (FED treatment) and; post-prandial juveniles injected with cycloheximide (FEDC treatment). Protein was the primary energy substrate (65% of oxygen consumption) for 2-day fasted juveniles, with lipid accounting for the remainder (35%). After 10-day starvation lipid became the main substrate, indicating lipid oxidation increased with extended fasting. Following feeding, protein contribution remained above 50%, while lipid (0–43%) and carbohydrate (0–37%) provided significant energy at different time periods, indicating besides protein appropriate proportions of non-protein ingredients are also essential to lobsters. SDA magnitude in FED and FEDC treatments estimated by the traditional approach was 10.5 and 0.4 J g−1, respectively, indicating S. verreauxi expended 96% of post-prandial energy on protein synthesis and that decapod protein synthesis can account for one of the highest proportions of SDA in aquatic ectotherms. SDA magnitude in the FED treatment evaluated by stoichiometry (12.6 J g−1) was comparable to the traditional approach. Interestingly, stoichiometry was not applicable in the FEDC treatment as the respiratory quotient exceeded the theoretical maximum under aerobic conditions. Cycloheximide did not affect CO2 excretion among all treatments or nitrogenous excretion among unfed treatments, while the post-treatment total nitrogenous excretion reduced in fed lobsters. The combined measurement of substrate use and SDA potentially helps optimize the feed to achieve sustainable aquaculture. However, more research is required to decipher limitations and the applicability of stoichiometry for crustaceans.