Florida Turtles Establish New Foothold in Pamplona Lake, Raising Ecological Concerns

Environmental authorities in Pamplona are grappling with a growing population of invasive Florida Slider turtles (Trachemys scripta elegans) in the Mendillorri lake. Recent captures have confirmed a significant presence, raising alarms about the potential impact on the local ecosystem and native species.

The Problem Unfolds

During a routine environmental monitoring mission in early July 2024, two environmental guards in Pamplona captured two Florida Slider turtles in the Mendillorri lake. Dani González, one of the officers involved, estimates that the current population in the lake could be around 100 individuals. This figure, while concerning, is a reduction from a decade ago. In October 2016, when the lake was emptied for the first time in twenty years, nearly 300 of these non-native turtles were discovered, alongside carp and even a catfish.

Management Efforts and Challenges

The proliferation of the Florida Slider, which is listed on the Spanish Catalogue of Invasive Exotic Species, has led to annual control campaigns since 2021. These campaigns, managed by the Department of Environment in Navarra, typically begin in June. The strategy exploits the turtles’ behavior of seeking out sunny spots to regulate their body temperature. Specially designed traps, featuring ramps that lead to a basking area, funnel the turtles into a floating net once they descend. Officers then collect the turtles by kayak and transport them to Wildlife Recovery Centers. While the 2016 operation was a one-time large-scale removal, the current approach involves continuous, smaller-scale interventions, yet the influx of turtles remains persistent.

Ecological Implications

The introduction of invasive species into an ecosystem can have severe consequences, and the Florida Slider is no exception. It directly competes with the native European pond turtle (Emys orbicularis), a species already considered threatened. The invasive turtles vie for essential resources like basking spots, crucial for thermoregulation, and food. Furthermore, the Florida Slider exhibits a significantly higher reproductive rate. American males reach sexual maturity at around five years, whereas European males can take up to sixteen years. Studies indicate that in mixed populations, the European pond turtle suffers from reduced weight and increased mortality, leading researchers to advocate for halting any further introductions of Florida Sliders into European wetlands.

A Global Issue with Local Roots

The Florida Slider’s journey to European lakes and rivers began with its popularity as a pet. As these turtles grew too large for their enclosures, they were often released into local waterways, leading to established populations. The International Union for Conservation of Nature (IUCN) lists the Florida Slider as one of the world’s 100 most harmful invasive alien species. The situation in Mendillorri is not unique; the widespread practice of releasing these pets has resulted in their presence across most of the continent’s wetlands. In Navarra alone, the control efforts have expanded to other municipalities, including Tudela, Corella, Funes, and Cintruénigo.

Responsible Pet Ownership and Conservation

Authorities emphasize that pets are not disposable commodities. The Department of Environment of the Government of Navarra, through its Director-General Ana Bretaña de la Torre, stated, “Natural species are not a toy; the environment cannot afford these intrusions.” She further explained the difficulty of eradicating an established invasive species, especially in natural waterways. This challenge is not limited to turtles; Navarra also hosts a significant population of American mink, which poses a direct threat to the European mink, a vulnerable native species. Recognizing the issue of pet abandonment, authorities provide a free service for citizens who can no longer care for their turtles, allowing for proper management without penalty, as an alternative to releasing them into the wild.

Key facts:
| Detail | Information |
| :———————- | :—————————————————————————- |
| Species | Florida Slider turtle (Trachemys scripta elegans) |
| Location | Mendillorri lake, Pamplona, Spain |
| Estimated Population | Approximately 100 individuals in Mendillorri lake (July 2024) |
| Previous Discovery (2016) | Nearly 300 turtles found when the lake was emptied |
| Status | Invasive Exotic Species in Spain; one of IUCN’s 100 most harmful invasive species |
| Impact | Competes with native European pond turtles, higher reproductive rate |

The ongoing presence of the Florida Slider in Pamplona’s natural spaces underscores a broader environmental challenge: the consequences of exotic pet ownership and the subsequent release of animals into non-native habitats. This situation highlights the critical need for public awareness regarding responsible pet ownership and the ecological damage caused by invasive species.

Source: El Galápago de Florida ha encontrado un nuevo hogar: un lago en un barrio de Pamplona. Hace una década encontraron 300 – Xataka: https://www.xataka.com/ecologia-y-naturaleza/galapago-florida-ha-encontrado-nuevo-hogar-lago-barrio-pamplona-hace-decada-encontraron-300

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