Invasive Redfin Perch Established in Lake Karāpiro, Officials Warn

The discovery of redfin perch in Lake Karāpiro has raised significant concerns among local officials regarding the impact on native fish species. An angler reported catching one of the invasive fish below the Arapuni Dam, prompting an investigation by Fish and Game, the organization responsible for managing fishing activities in New Zealand.

Richie Cosgrove, chief operating officer of Fish and Game, confirmed that the exact method of how the redfin perch entered Lake Karāpiro remains unclear. He noted, “Perch are widespread throughout New Zealand, including the Waikato River, and are managed by Fish and Game as a sports fish.” This highlights the complexity of managing invasive species in environments where they can thrive alongside native populations.

While redfin perch are considered edible and can be legally caught with a fishing licence, Fish and Game is keen on preventing the species from spreading to additional locations. According to Cosgrove, complete eradication of the perch from Lake Karāpiro is not feasible due to the established breeding population and the lake’s size and ecological complexity. “Eradication was not feasible,” he stated, emphasizing the challenges posed by the current methods of removal.

The presence of redfin perch poses a potential threat to the balance of local ecosystems. As an invasive species, they can compete with native fish for resources, potentially leading to declines in local fish populations. The ongoing management efforts by Fish and Game will focus on monitoring the situation and addressing the ecological impact of this new addition to the lake.

In light of these developments, local anglers and residents are urged to report any further sightings or catches of redfin perch to help assess the situation. Fish and Game remains committed to safeguarding New Zealand’s native fish species while navigating the complexities of managing invasive populations. The agency continues to monitor Lake Karāpiro closely to understand the full implications of this new fish species on the local ecosystem.