Biological Invasions (2009) 11, 1557-1567

James C. Russell, Jawad Abdelkrim and Rachel M. Fewster (2009)
Early colonisation population structure of a Norway rat island invasion
Biological Invasions 11 (7), 1557-1567
Abstract: Colonists undergo non-equilibrium processes such as founder effects, inbreeding and changing population size which influence the mating system and demography of a population. Understanding these processes in colonising populations informs management and helps prevent further invasions. We sampled and genotyped most individuals of a Norway rat (Rattus norvegicus) reinvasion on Moturemu island (5 ha) in New Zealand. Population size was most likely between 30 and 33 rats. Genetic methods detected a clear bottleneck signal from the founding population. Parentage assignment revealed promiscuous mating dominated by a few individuals with increasing inbreeding, both putatively a result of small island size. Combining ecological and genetic data from a single sample allowed inferences on population structure and functioning. Invading Norway rats rapidly achieve population structure similar to established island populations despite a small number of colonists and associated inbreeding. Overcoming these initial obstacles to population establishment contributes to the global success of invasive rats.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website

Research topic(s) for pests/diseases/weeds:
population dynamics/ epidemiology
molecular biology - genes

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Rattus norvegicus		New Zealand