Retired Lethbridge professor Joe Rasmussen has new species of aquatic parasite named after him

Retired University of Lethbridge professor Joe Rasmussen recently had a new species of aquatic parasite named after him. (Photo: University of Lethbridge)

A retired University of Lethbridge professor is being recognized by having a newly-discovered aquatic parasite named after him.

The unique scientific honour came about after a U of L undergraduate, Molly Tilley, discovered large, white lesions surrounding the eyes of the fathead minnows in the university’s pond.

That led to what Tilley and supervisor Dr. Cam Goater describe as an “emerging parasite” capable of disrupting the aquatic food chain – which, given its discovery in the waters of southern Alberta, the duo named  Myxobolus rasmusseni as a tribute to retired U of L aquatic biologist Joe Rasmussen.

“Joe and I had been close friends and colleagues for many years,” said Goater, in a university media release. “His stature within Canadian science circles is legendary — I can’t think of an award in his field that he hasn’t won.

"Naming this parasite after him was another way to honour his range of contributions. To me, he is the top aquatic biologist in the country, maybe North America, and nobody is more deserving of a recognition of this type.”

The new parasite is known as a myxozoan, the same type of parasite known to cause “whirling disease” in trout. It’s been spreading quickly throughout western North America, and posing challenges for fisheries management and conservation.

Myxobolus rasmusseni is a variation of that one, which infects fathead minnows, which are a significant factor in the food chain in prairie ponds and lakes.

“The problem is that fatheads tend to occur in the middle of our aquatic food chains,” said Goater. “Pike eat them, trout eat them and all sorts of fish-eating birds like herons and pelicans eat them.

"Our worry," he added, "is that infection rates are often so high in juvenile minnows that they are unlikely to survive through the winter to reproduce the following spring. You’re really upsetting the ecosystem by losing a key part of the food chain.”

U of L undergraduate student Molly Tilley and supervisor Dr. Cam Goater named the new species Myxoblus rasmusseni, paying tribute to Dr. Joe Rasmussen. (Photo: University of Lethbridge)

'Integral component'

Rasmussen, who taught at the University of Lethbridge for 16 years, said having a new species named after himself is pretty special.

“The naming of species is an integral component of the communication of information about nature, and the stability of our system for describing and naming new organisms is a cherished aspect of our science,” he says.

“To have your name attached to a new species is, therefore, one of the finest forms of immortality that can be conferred, and to be recognized in such a distinguished manner by my colleague Dr. Goater and his student, Molly Tilley, is gratifying beyond words.

“Indeed, my involvement with Dr. Goater as a friend and colleague has been a major highlight in my career at the University of Lethbridge.”

Tilley just finished her master’s thesis – it was about the discovery of M. rasmusseni.

She said she’s writing a new paper about the effect of M.rasmusseni on individual minnow behaviour and survival.

“The results suggest that not only does infection with M. rasmusseni ultimately cause the death of the host, we found that infection reduces the physiological performance of individual fish which in turn impacts their functional role in the ecosystem,” she says.

“This work will provide a solid foundation for future research which could ultimately inform management strategies.”