Abstract
Aim
Research on amphibian invasions has largely focused on the likelihood of successful establishment, while analysis of the previous stages in the invasion pathway (transport and introduction) is scarce despite its critical importance. Here, we investigate the patterns of taxonomic and geographic non‐randomness as well as the factors affecting the transport and introduction of amphibians.
Location
Australia.
Methods
We compiled and analysed a database on the identity of transported and introduced amphibians. First, we tested for taxonomic (family level) and geographic non‐randomness by comparing transported and introduced species with all extant caudates and anurans. Second, we constructed models to examine the influence of different factors upon the probability of transport and introduction of amphibians in Australia.
Results
Amphibians were transported via two main pathways: trade (71 species) and stowaway (38 species). In addition, several species were transported through both pathways. Transported species represented a taxonomic and geographic non‐random sample of all extant amphibian species. Conversely, introduced species constituted a random sample of the transported amphibians. Regardless of the transport pathway, the probability of transport of amphibians increased with increasing extent of their native geographical range. A large number of native Australian species have been transported outside their naturally occurring ranges, representing over 65% of the introduced species. Introduction is strongly correlated with the transport pathway, that is, species transported through two pathways were more likely to be released or escape from captivity.
Main conclusions
The probability of amphibians being transported and introduced to, or within, Australia is critically affected by their availability to be captured, bred and housed in captivity. Management strategies to prevent the future introduction and establishment of new amphibians need to include the people involved in species trade, as well as continued vigilance by biosecurity and custom agencies.
Research on amphibian invasions has largely focused on the likelihood of successful establishment, while analysis of the previous stages in the invasion pathway (transport and introduction) is scarce despite its critical importance. Here, we investigate the patterns of taxonomic and geographic non‐randomness as well as the factors affecting the transport and introduction of amphibians.
Location
Australia.
Methods
We compiled and analysed a database on the identity of transported and introduced amphibians. First, we tested for taxonomic (family level) and geographic non‐randomness by comparing transported and introduced species with all extant caudates and anurans. Second, we constructed models to examine the influence of different factors upon the probability of transport and introduction of amphibians in Australia.
Results
Amphibians were transported via two main pathways: trade (71 species) and stowaway (38 species). In addition, several species were transported through both pathways. Transported species represented a taxonomic and geographic non‐random sample of all extant amphibian species. Conversely, introduced species constituted a random sample of the transported amphibians. Regardless of the transport pathway, the probability of transport of amphibians increased with increasing extent of their native geographical range. A large number of native Australian species have been transported outside their naturally occurring ranges, representing over 65% of the introduced species. Introduction is strongly correlated with the transport pathway, that is, species transported through two pathways were more likely to be released or escape from captivity.
Main conclusions
The probability of amphibians being transported and introduced to, or within, Australia is critically affected by their availability to be captured, bred and housed in captivity. Management strategies to prevent the future introduction and establishment of new amphibians need to include the people involved in species trade, as well as continued vigilance by biosecurity and custom agencies.
| Original language | English |
|---|---|
| Pages (from-to) | 455-466 |
| Number of pages | 12 |
| Journal | Diversity and Distributions |
| Volume | 20 |
| Issue number | 4 |
| Early online date | 10 Mar 2014 |
| DOIs | |
| Publication status | Published - Apr 2014 |
Bibliographical note
C. Ayres, M. Lorenzo, M. Vall-llosera, C. Morrison, M. Tyler,J. Ross, A. Woolnough, R. Keller and two anonymous refer-ees provided comments that greatly improved a first draft ofthe manuscript. E. Smee kindly provided the datasets oninternational flights. PG-D is funded by an IPRS/APA schol-arship by the Commonwealth Government of Australia(DEEWR) and an Invasive Animals CRC PhD scholarship.PC is an ARC Future Fellow (FT0914420)Keywords
- anura
- candida
- exotic species
- invasion pathway
- wildlife trade