Fighting over burrows : the emergence of dominance hierarchies in the Norway lobster (Nephrops norvegicus)

Sbragaglia, Valerio; Leiva, David; Arias, Anna; Garcia, Jose Antonio; Aguzzi, Jacopo; Breithaupt, Thomas

Abstract

Animals fight over resources such as mating partners, territory, food or shelter and repeated contests lead to stable social hierarchies in different phyla. The group dynamics of hierarchy formation are not characterized in the Norway lobsters (Nephrops norvegicus). Lobsters spend most of the day in burrows and forage outside of them according to a diel (i.e. 24-h based) activity rhythm. Here, we use a linear and generalized mixed model approach to analyse, in 7 groups of 4 male lobsters, the formation of dominance hierarchies and rank related changes in burrowing behaviour. We show that hierarchies emerge within 1 to 3 days and increase in steepness over a period of 5 days, while rank changes and number of fights gradually decrease over a 5 day period. The rank position determined by open area fights predicts the outcome of fights over burrows, the time spent in burrows, and the locomotor activity levels. Dominant lobsters are more likely to evict subordinate lobsters from their burrows and more successful in defending their own burrows. They spend more time in burrows and display lower levels of locomotor activity outside the burrow. Lobsters do not change their diel activity rhythms as a result of a change in rank, and all tested individuals showed higher activity at night and dusk compared to dawn and day. We discuss how behavioural changes in burrowing behaviour could lead to rank related benefits such a reduced exposure to predators and energy savings.

Citation

Sbragaglia, V., Leiva, D., Arias, A., Garcia, J. A., Aguzzi, J., & Breithaupt, T. (2017). Fighting over burrows : the emergence of dominance hierarchies in the Norway lobster (Nephrops norvegicus). The journal of experimental biology, 220(24), 4624-4633. https://doi.org/10.1242/jeb.165969

• Journal Article Type: Article
• Acceptance Date: Oct 13, 2017
• Online Publication Date: Oct 19, 2017
• Publication Date: Dec 15, 2017
• Deposit Date: Oct 20, 2017
• Publicly Available Date: Oct 23, 2018
• Journal: Journal of experimental biology
• Print ISSN: 0022-0949
• Electronic ISSN: 1477-9145
• Publisher: The Company of Biologists
• Peer Reviewed: Peer Reviewed
• Volume: 220
• Issue: 24
• Pages: 4624-4633
• DOI: https://doi.org/10.1242/jeb.165969
• Keywords: Nephrops norvegicus; Dominance hierarchy; Fighting; Burrow; Locomotor activity; Biological rhythms
• Public URL: https://hull-repository.worktribe.com/output/455884
• Publisher URL: http://jeb.biologists.org/content/early/2017/10/19/jeb.165969.long
• Additional Information: Copy of article published in Journal of experimental biology, 2017.