Non-invasive invaders from the Caribbean: the status of Johnstone’s Whistling frog (Eleutherodactylus johnstonei) ten years after its introduction to Western French Guiana

Abstract

The neotropical frog Eleutherodactylus johnstonei (Anura: Eleutherodactylidae) has been referred to as a highly invasive species on grounds of its wide distribution and is expected to extend its range significantly based on recent climate model assumptions.

Whistling invaders: Status and distribution of Johnstone’s Whistling frog (Eleutherodactylus johnstonei Barbour, 1914), 25 years after its introduction to Colombia

“…At the country level, E. johnstonei is restricted to urban or disturbed urban peripheral areas as previously reported from countries outside the native range (e.g. Ernst et al 2011;Kaiser 2002;Montes and Bernal 2012). Moreover, the distribution within the respective urban matrix is not random but habitat specific.…”

“…This pattern was confirmed in the present study, indicating that no significant migration into the surrounding matrix took place within the past 16 years. A low capacity for active dispersal was previously also reported for non-native populations in French Guiana (Ernst et al 2011). It is well known that significant lag phases can exist between particular invasion phases (Kowarik 1995) and land use changes, including growth and expansion of urban centres may enhance further spread of the species by counteracting present day dispersal limitations.…”

“…Macroecological models, mainly based on coarse-grained climate data, even predict a very high invasion potential far beyond its natural Caribbean range (Rödder 2010) and the current distribution on the South American mainland seems to corroborate this notion. Despite this wide distribution, active dispersal beyond non-natural, human modified habitats could not convincingly be shown to be a realistic scenario (Kaiser 1997(Kaiser , 2002Ernst et al 2011). Yet, the majority of studies consider the invasion potential to be high and thus propose proactive eradication measures (Melo et al 2014) Amongst all countries, to which E. johnstonei has been introduced successfully, Colombia deserves special attention because of the comparatively long introduction history and the large number of populations reported to have established in different parts of the country.…”

Introduced bullfrogs are associated with increased Batrachochytrium dendrobatidis prevalence and reduced occurrence of Korean treefrogs

“…Multicollinearity among all variables was examined prior to the statistical analysis through the use of Variance Inflation Factors (VIF [50]), instead of bivariate correlations to avoid simple pairwise comparisons of correlations [51]. Because VIF values were between 1.003 and 2.340, all variables were included in the subsequent analyses.…”

Establishment risk from pet-trade freshwater turtles in the European Union

“…In contrast to plants, the invasiveness of animals, and especially vertebrates, has attracted much less attention in the past (Pyšek et al, 2010). Reptiles, in particular, have been widely overlooked in systematic invasion studies (Kraus, 2009;Bomford et al, 2009;Henderson et al, 2011), and their establishment potential and invasion dynamics remain poorly understood (Ernst et al, 2011). Delivering Alien Invasive Species Inventory for Europe -DAISIE (2012) recognizes in Europe 72 alien reptile species.…”