New findings may help transform how invasive brown bullhead catfish are managed in Lake Rotoiti. By tracking tagged fish throughout the year, Paul Blanchfield and other Fish Futures’ researchers discovered that catfish move into shallow lake-edge habitats during spring and summer, making them more vulnerable to capture with fyke nets. In winter, they disperse into deeper offshore waters, where current control methods are less effective. The study also found catfish are attracted to warmer water, highlighting geothermal areas as promising targets for future control efforts. These insights could help improve catfish management and protect native freshwater ecosystems.
We also created this cool gif to show how the fish move across seasons.
Cawthron Institute has also produced a short, accessible summary of the manuscript to help managers, iwi, and community groups quickly understand the key findings and their practical implications.