Biology ETDs

Publication Date



Alien species are one of the principal threats to global biodiversity. Insular ecosystems have proven exceptionally susceptible to invasion by aliens and vulnerable to their negative effects. Some of the most destructive alien species are vertebrates, in part due to their having been introduced to islands worldwide. Rodents (Rattus spp. and Mus musculus) are among the most widespread and devastating invasive species for insular flora and fauna. In this research I investigate the biogeographic patterns and processes of alien vertebrates in the Galapagos Islands, focusing on the mechanisms that influence their dispersal and colonization within the archipelago. In the first study, I review and synthesize the available literature on alien vertebrates in the Galápagos. I investigate the impacts to the native flora and fauna from alien vertebrates and the spatial and temporal patterns of colonization in the archipelago. I summarize management efforts directed at alien vertebrates and assess the potential future impacts to the Galapagos from alien vertebrates. In the second study, I examine the distribution of the three alien rodents from a biogeographic perspective. Island area and isolation from a source population are examined to determine the influence of these landscape features on the incidence of a rodent species on an island. In the third study, I conduct a multivariate analysis of the biotic and abiotic factors influencing intra-archipelago dispersal and colonization of two alien rodents. Using this analysis the probability of an alien rodent occurring on an island is determined and the risk of invasion to other islands is estimated.




alien species, black rat, distribution, Galápagos Islands, house mouse, invasion, modeling, Norway rat, vertebrates

Document Type


Degree Name


Level of Degree


Department Name

UNM Biology Department

First Committee Member (Chair)

Brown, James H.

Second Committee Member

Milne, Bruce T.

Third Committee Member

Dowler, Robert C.