In an extraordinary incident that has sparked intrigue and concern among scientists, a French herpetologist has captured an image of a snake choking on a fish of equivalent size to its own head. The snake, identified as a Viperine (Natrix maura), was found in a distressing state at Lac de Carcès in southeastern France, as it attempted to consume a fish that was lodged in its esophagus. This occurrence, while fascinating, has highlighted the pressing need for more research into the impact of invasive fish species on local snake populations.

The fish, identified as a Ruffe (Gymnocephalus cernua), is an invasive species in this part of Europe. Ruffes, known for their tough and spiny dorsal fins, present a formidable challenge to predators attempting to swallow them. While Viperine snakes and Ruffes have overlapping native regions, it is worth noting that Ruffes are an invasive species in Mediterranean wetlands where Viperine snakes are rare and declining. This decline is attributed to multiple threats including river pollution, wetland destruction, urbanization, and potentially, the introduction of invasive species like the Ruffe.

French Herpetologist Rescues Struggling Snake from Invasive Fish

A Fish Too Tough to Swallow

In an unusual occurrence, a herpetologist in France recently photographed a snake choking on a fish the same size as its own head. While numerous snake species are known to consume fish, this particular fish species is considered invasive in this part of Europe. Nicolas Fuento, a herpetologist at the nonprofit League for the Protection of Birds in France, who observed this phenomenon, suggests that this encounter should spark further research into the relationship between fish-eating snakes and invasive species.

A Viperine Snake’s Struggle

The incident took place at Lac de Carcès in southeastern France where Fuento encountered a struggling viperine snake (Natrix maura) trying to eat a ruffe (Gymnocephalus cernua). Initially, he assumed the snake was merely attempting to consume the fish. It was only when he noticed the snake’s unusual spasmodic movements that he realized it was in difficulty. The fish appeared to be lodged in the snake’s esophagus, leading Fuento to intervene.

The Rescue Operation

Fuento enlisted an intern to hold the snake while he attempted to remove the fish. The task proved challenging as the fish’s dorsal spines were stuck in the snake’s esophagus. Fuento successfully dislodged the fish by gently pushing it into the snake’s mouth, likening the process to removing a hook from a fish’s mouth. Upon being relieved of the fish, the snake seemed uninjured and was able to slither away beneath a rock.

An Invasive Species’ Impact

The ruffe, a small freshwater fish native to parts of Europe and Asia, has been introduced to North America and other parts of Europe, including France. Its tough and spiny dorsal fins may pose a challenge for its predators, including snakes, to swallow. Fuento’s paper suggests that the introduction of ruffes could pose an additional threat to the local snake population, which is already declining due to river pollution, wetland destruction, and urbanization. However, the actual impact of these invasive fish on the snake population has yet to be studied.

Looking Forward

The paper also notes other instances where fish-eating snakes, including viperine snakes, have died after consuming invasive fish species. But, it also mentions that some snakes seem to have the ability to avoid these "harmful alien fishes". Fuento hopes that this incident might lead to further research on the subject, shedding light on the potential threat of invasive species to native wildlife.

Takeaways

This incident highlights the complex and often unpredictable interactions between native and invasive species. It emphasizes the importance of understanding and monitoring these interactions, as they can have significant impacts on local ecosystems. Furthermore, it underscores the potential risks that invasive species pose to native wildlife. As such, the research calls for further study into this subject, with the hope of finding strategies to mitigate these impacts and protect these delicate ecosystems.