Differences in aggressive behaviour along the expanding range of an invasive crayfish: an important component of invasion dynamics
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Aggressive interactions are essential for resource distribution and population dynamics of many animal species. Aggression can also help invasive species to wrestle the resources from other species and invade new habitat. To examine the effects of intra-species aggression on range expansion, we compared aggression levels of signal crayfish (Pacifastacus leniusculus) at the core and front of the invasion range in recently invaded regions of Croatia. More pronounced aggression was observed in core populations with high population densities, indicating potentially greater importance of highly aggressive behaviour in populations with higher competitive pressure. Despite better overall physical condition, individuals at the invasion front generally displayed lower levels of aggression and regularly lost interactions to individuals from the invasion core. Rather than providing a competitive advantage during range expansion, aggression may be more expressed in established populations, priming the individuals for future expansions while also driving the dispersal outward. The observed difference in aggression along the invasion pathway demonstrates that traits that help individuals to overcome challenges of their environment, such as competition against conspecifics, can drive the invasion dynamics of a successful invader in a new environment in terms of both niche competition and intrinsic expansion dynamics.
KeywordsAggression Dispersal Invasive species Freshwater invasion Range expansion
We thank Nina Jeran, Andreja Lucić and Krešimira Trgovčić for their help during fieldwork. This research was financially supported by Croatian Ministry of Science, Education and Sports (Project No. 119-1193080-1231). KH was supported by the Science and Industry Endowment Fund’s John Stocker Fellowship.
- Bovbjerg R (1956) Some factors affecting aggressive behavior in crayfish. Physiol Zool 29:127–136Google Scholar
- Gajić-Čapka M, Zaninović K (2004) Climate conditions in the Sava. Drava and the Danube River Basins Croatian waters 12(49):297–312Google Scholar
- Hudina S, Hock K, Žganec K (2014) The role of aggression in range expansion and biological invasions. Curr Zool 60(3):401–409Google Scholar
- Moore PA (2007) Agonistic behavior in freshwater crayfish: The influence of intrinsic and extrinsic factors on aggressive behavior and dominance. In: Duffy JE, Thiel M (eds) Evolutionary ecology of social and sexual systems: Crustacea as models organisms. Oxford University Press, Oxford, pp 90–114CrossRefGoogle Scholar
- Nakata K, Goshima S (2003) Competition for shelter of preferred sizes between the native crayfish species Cambaroides japonicus and he alien crayfish species Pacifastacus leniusculus in Japan in relation to prior residence, sex difference, and body size. J Crust Biol 23:897–907. doi: 10.1651/C-2411 CrossRefGoogle Scholar
- Pavey CR, Fielder DR (1996) The influence of size differential on agonistic behaviour in the freshwater crayfish, Cherax cuspidatus (Decapoda: Parastacidae). J Zool 238(3):445–457. doi: 10.1111/j.1469-7998.1996.tb05405.x
- Souty-Grosset C, Holdich D, Noel P, Reynolds JD, Haffner P (2006) Atlas of crayfish in Europe. Museum National d’Histoire Naturelles, ParisGoogle Scholar
- Tierney A, Godleski M, Massanari J (2001) Comparative analysis of agonistic behavior in four crayfish species. J Crust Biol 20:54–66. doi: 10.1651/0278-0372(2000)020[0054:CAOABI]2.0.CO;2
- Twardochleb LA, Olden JS, Larson ER (2013) A global meta-analysis of the ecological impacts of nonative crayfish. Freshw Sci 32(4):1367–1382. doi: 10.1899/12-203.1
- Zar J (1999) Biostatistical analyses. Prentice Hall, LondonGoogle Scholar