Rare Transmissible Cancer Found in Bullhead Catfish | Montpelier News

Montpelier News Today | 2 Min New | The Daily News Now! · Jul 22, 2026 · 1m

Scientists have uncovered a rare, contagious cancer in bullhead catfish from Lake Memphremagog that behaves like a parasite, spreading between fish — a phenomenon previously seen only in dogs and Tasmanian devils. Genetic analysis confirms the tumors are melanomas, with cells more alike across fish than to their own bodies. Anglers have long reported black, tar-like growths, now understood to be a transmissible cancer affecting up to one-third of the local population. While the exact transmission method remains unknown — possibly linked to spawning behaviors — the cancer hasn’t yet caused…