Pets and invasion risks: is the Slider turtle strictly carnivorous?

Abstract

According to the International Union for Conservation of Nature (IUCN), invasive species are one of the most important causes of biodiversity decline at a global scale. The impact of introduced species on local ecosystems is thus important to evaluate. Pet voluntary introductions are made by private people and usually concern only one or two individuals per occasion. However, the number of release occasions is as numerous as the number of pet owners that don't want to keep their pet anymore and then decide to "release" it. Hatchling red-eared slider turtles (Trachemys scripta elegans) have been massively exported from the United States to European (until 1997) and Asian countries to be sold as pets. Many owners, ignoring the potential consequences of their act, have released their grown up turtle in natural freshwater ecosystems. As a consequence, feral adult turtles have been detected all over France. In this paper, we provide information that contradicts public opinion that introduced slider turtle is strictly carnivorous. By analysing the diet of feral adult turtles, we found that adult slider turtles are omnivorous, as in their natural areas.

Minimizing false‐negatives when predicting the potential distribution of an invasive species: a bioclimatic envelope for the red‐eared slider at global and regional scales

“…In their exotic range, RES outcompete native turtles [e.g. European pond turtles Emys orbicularis; (Lever, 2003)] disrupt food-webs by consuming aquatic vegetation, invertebrates and vertebrates (Ernst, Lovich & Barbour, 1994;Ligon, 2007;Prevot-Julliard et al, 2007) and negatively affect birdlife, for example by drowning eggs while basking in water-bird nests (ISSG, 2006). The RES is native to the Mississippi Valley area, USA, and has established wild populations in several countries, including Australia, Spain, France, Italy, Taiwan, Japan, Guam, among others outside of its native range in North America, (Ng, Chou & Lam, 1993;Chen & Lue, 1998;Bomford, 2003;Lever, 2003;ISSG, 2004;Ficetola, Thuiller & Padoa-Schioppa, 2009).…”

Plastic ingestion by freshwater turtles: a review and call to action

“…Our comprehensive review of turtle dietary literature published prior to 2021 revealed that all 7 marine turtle species (100%) have been documented ingesting plastic 5 . In contrast, only 5 of 352 non-marine turtle species (1.4%) have been documented ingesting plastic 23 , 39 – 43 . All five are aquatic species (Table S1 ).…”

“…Turtle ingestion of synthetic fishing line is also frequently reported 44 – 46 , but because this fishing line is likely ingested inadvertently when turtles take baited fish hooks or lures 47 , 48 , we consider this a very different form of plastic pollution and do not discuss these records further. Additionally, we identified eight non-marine turtle species that have been reported ingesting non-plastic litter 23 , 41 – 43 , 49 – 58 . These eight include both aquatic and terrestrial species (Table S1 ).…”

“…For non-marine turtles, only three plastic ingestion frequencies are available. A plastic ingestion frequency of 21.6% is reported for Graptemys flavimaculata 40 , while frequencies of 32.0% 43 and 40.6% 23 are reported for Trachemys scripta elegans and T. dorbigni , respectively. However, the frequencies of the latter two studies are inflated to an unknown degree, because they combine plastic with other human litter and debris (paper and/or stones).…”

A looming exotic reptile pet trade in India: patterns and knowledge gaps

“…Young Red-eared Slider turtles are carnivorous; they undergo a shift in diet as they mature to become omnivores (Ligon 2007;Boyer & Scott 2019) and predate on native species of turtles (Vyas 2020). They prey on local fish species and may compete for food and nesting space with the native turtle populations (Girondot et al 2007).…”