Dr. Mark McMaster Talks Fish Tumours with InfoSuperior
Posted on: May 24, 2016

In anticipation of his upcoming presentation in Thunder Bay, the InfoSuperior Team caught up with Dr. Mark McMaster to give us a preview of his talk on “Fish Tumours and Other Deformities.” Click on the play button below to listen to the full interview.

Everyone is welcome to come see Dr. McMaster present on June 1st. The meeting will be held at Richardson International Grain Terminal at 303 Shipyard Drive, Thunder Bay, ON. The meeting will be held from 7-9pm, is free to attend, and light refreshments will be served. For more info, check our ‘Meetings’ page here.

Chatting with us from his office at the Canadian Centre for Inland Waters in Burlington, ON, McMaster told InfoSuperior’s Jim Bailey that while he is more of a fish reproductive toxicologist than a tumour expert, he has done a lot of research on the subject in the last decade. As part of his role at Environment and Climate Change Canada, and with funding through the Great Lakes Action Plan, McMaster and Dr. Paul Baumann evaluated tumour levels present in white sucker fish in Thunder Bay in 2007. Fish tumours were one of the initial impairments which led to Thunder Bay being listed as an area of concern in 1987.

What McMaster and Baumann found in 2007 was that tumour levels were low, but the fish being examined were very young. Baumann’s recommendation was to re-evaluate again in a few years, repeating the sample research after the fish had time to mature. McMaster returned in 2013 to do so, and it is these findings that he’ll be presenting June 1st at Richardson International Grain Terminal.


To do the research, McMaster says he collects samples of species that are exposed to contaminated sediments. In the lower Great Lakes, brown bullhead are used for the sample. In Superior, samples of white sucker fish are collected, which are bottom-feeding. Since tumour levels are generally pretty low, McMaster says he needs a large sample size – about 100 fish from each area.

In August 2013, McMaster carried out his research and collected 100 white suckers from the Thunder Bay area. With preserved liver tissue from the sample, preliminary analysis was done at the Canadian Centre for Inland Waters, and then contracted out to a fish pathologist from the Ministry of Agriculture in British Columbia to do final assessment for tumours.

McMaster has worked across the Great Lakes and studied fish health in all Canadian areas of concern. He’s now doing research in the Athabasca River to monitor the effects of oil sands on fish.

Having done research in Terrace Bay for his masters and PhD degrees, McMaster says he has fond memories and good friends from the North Shore of Superior and he retains a keen interest in the area. It’s “by far a favourite” site for him to work at, and he looks forward to returning to present on June 1st.