Agonistic behaviour and energy metabolism of bold and shy swimming crab Portunus trituberculatus

Abstract

The metabolism and behaviour of crustaceans are highly flexible, and the inter-individual variation in these traits is evolutionarily and ecologically significant. We analysed the relationships among personality traits (boldness, activity and hesitancy), agonistic behaviour and energy status (glycogen, glucose and lactate) in the swimming crab Portunus trituberculatus. The main results were as follows. (1) Boldness was significantly correlated with activity and hesitancy. Bold crabs were more likely to initiate and win a fight. In bold individuals, the frequencies of 'move to', 'cheliped display', 'grasp' and 'contact' were significantly higher than those of shy individuals, whereas the frequency of 'move away' was significantly lower than that of shy individuals. (2) Before fighting, the glucose concentrations in the haemolymph of bold individuals were significantly lower than those of shy individuals, whereas the concentrations of lactate showed the opposite trend. There were no significant differences in glycogen and lactate concentrations in the claw muscle between bold and shy individuals. (3) After fighting, the glucose and lactate concentrations in the haemolymph of both bold and shy individuals were significantly higher than those before fighting. The glucose concentrations in the haemolymph were significantly higher in bold individuals than shy individuals. In addition, bold individuals showed a larger increase in glucose in the haemolymph but a smaller increase in lactate compared with shy individuals. (4) After fighting, the glycogen concentrations in the claw muscle were significantly lower than those before fighting; however, there were no significant differences in the concentrations of lactate in the claw muscle. These results indicated that the agonistic behaviour of the swimming crab is related to its behavioural type. Energy reserves may be one of the factors affecting the personality traits and agonistic behaviour in crabs. These results should lay a foundation for in-depth understanding of the relationships among crustacean personality, agonistic behaviour and metabolic physiology.

Feeding strategy changes boldness and agonistic behaviour in the swimming crab ( Portunus trituberculatus )

“…One of the individuals was randomly selected to be marked (painted) with a white dot (Liquitex HB, Liquitex Artist Materials) on the top of its carapace for distinction and to facilitate observation during the fighting. In this experiment, food is the contest resource reference to previous studies length × width: 20 × 20 cm) and H, Separator board (60 × 50 cm) glucose and lactate concentrations of crabs after fighting in the S0 bold individuals-S3 bold individuals matched fights, and crabs were removed from the aquarium with minimal disturbance and quickly placed in cold water to produce general anaesthesia (Su et al, 2019).…”

A New Method of Aquatic Animal Personality Analysis Based on Machine Learning (PAML): Taking Swimming Crab Portunus trituberculatus as an Example

“…For a personality characteristic, the more the color tends to red, the stronger the personality characteristics numerically; the more the color tends to blue, the weaker the personality characteristics numerically. relationship between various aspects of the organism (Su et al, 2019), but cannot perform cluster analysis or quantitatively analyze multi-factor impacts. In contrast, the PAML method proposed in this study can conduct a more comprehensive and direct analysis of the original data based on K-Means and SVM, which not only realizes an objective classification of the personality types of the swimming crabs, but also can evaluate the influence of different personality characteristics on personality classification.…”

“…Using the personality behavior observation system established in our previous study (Su et al, 2019), behavior observations were carried out on acclimated swimming crabs at intermolt stage with normal feeding and complete appendages. The crabs were allowed to acclimate for 10 min in the shelter, and then the trapdoor was remotely opened, thus allowing the crabs to access the experimental area while the infrared cameras recorded their behaviors.…”

“…During the study, a quiet environment and evenly distributed light were provided, and the conditions of light and water temperature were the same as during the maintenance period. After the behavior observations were completed, the videos were analyzed using behavior analysis software (Etho Vision XT 10) to quantify the boldness, activity, and hesitancy of the individual crab according to our previous study (Su et al, 2019).…”

The Developmental Plasticity of Boldness and Aggressiveness in Juvenile and Adult Swimming Crab (Portunus trituberculatus)

“…Boldness and aggressiveness are two personality traits that have received increased attention (Wolf et al, 2007;Ariyomo and Watt, 2012), as these traits affect the interactions between preys and predators (Coleman and Wilson, 1998), individuals, and conspecifics (Su et al, 2019). Boldness behavior refers to the tendency of individuals to take risks and explore new environments (Wilson and Godin, 2009).…”