A city stream once rendered all but lifeless due to erosion and pollution now boasts lush banks and a surprising abundance of fish — including one that had not been documented until this week.
On Monday, a team of researchers affiliated with the Junction Creek Stewardship Committee and Laurentian University identified a logperch — a small, vertically striped member of the Percidaefamily that needs clear water to thrive — in a section of the rehabbed waterway near the Louis Street playground.
“As far as we know there are 17 species of fish in Junction Creek, so to have what appears to be an 18th is pretty exciting,” said Brandon Holden, project coordinator with the stewardship committee.
The researcher was among a half-dozen people carrying out a fish survey this week in several sections of the creek near downtown, with some crewmembers donning electrofishing packs to stun the little swimmers, while others measured, weighed and categorized them before they were revived and returned to their watery home.
“It’s a summer-long project,” said Holden. “We’re sampling the entire upper reach of Junction Creek, which goes from the headwaters in Garson down to Kelly Lake. The whole idea is to get a better idea of the health of Junction Creek, and one way to do that is to look at the biodiversity of fish, because they can be indicators of stream health. So we’re looking at the relative abundance and diversity of fish species along each section of the creek.”
A similar fish project was carried out in 2004, he said, as well as 2008, but this one is a bit more comprehensive.
And with the years that have elapsed since the last study, it was a good time to take another look, Holden said, with funding help from the World Wildlife Fund, which is trying to fill in data gaps for areas of Northern Ontario.
“It’s been more than a decade, so we will be comparing the results of this year’s study with those past results to get an idea of how the creek has been changing,” he said. “This will better inform our restoration activities, because we can target those areas where we’re not seeing much improvement and maybe do more tree planting or shoreline stabilization.”
Fish are collected in a couple of different ways. “Depending on the site conditions we will either drop traps or electrofish,” he said.
The latter requires a solid river bottom and wadeable depth, as you don’t want to sink in muck or have water to your armpits while wielding a jolt-delivering wand.
While the data has yet to be analyzed, Holden said he has been generally impressed by the variety and density of fish the group is encountering.
“I know in the past there were sections where there weren’t many fish or really anything living, so I’m kind of pleasantly surprised to see that there’s lots of fish wherever we go so far,” he said.
The group has encountered a few brook trout, which the committee plants each spring in the creek, as well as perch and sunfish, but in general it is the smaller varieties that would be classified as minnows or baitfish that are filling their buckets.
“We’re finding a lot of creek chub, dace in certain sections, shiners, fatheads,” he said. “We’ve found some suckers and a catfish or two, but most commonly we’re seeing minnows. They were never totally extirpated from the creek, so as their habitat comes back, they are able to spread out over time and generations.”
Stephanie Theriault, a zoology student at Laurentian, has been involved in the project since it began, collecting information toward a fourth-year thesis for biology prof Mery Martinez.
“I’ve been doing it since late June and it’s been a blast to work in the creek all summer,” she said.
Theriault said her focus is on a stretch of the creek close to downtown, and how fish numbers and distribution have changed in this area since it was last analyzed.
“The 2008 study specified which fish were in each reach, so I’m really interested to see if any of the brook trout have maybe moved, or if there are any new species,” she said.
Theriault said it was a thrill this week to encounter at least one new species, when the logperch — since confirmed in a lab analysis — came across her examination table (the lid of a cooler) during fieldwork.
“For me it’s a sign of increased distribution in the creek,” she said. “And I think they’re a pretty sensitive species, too. I haven’t really read up on them that much yet, but when we do process the results, I’d be excited to find out if they are a bioindicator at all.”
A bioindicator is a species that points to ecosystem health, being unable to survive unless ideal — or close to ideal — conditions are met.
Brook trout — or speckles, as many call them — are the key bellwether species for Junction Creek, but the presence of the smaller, stripy darter could also be a good sign.
“Brook trout are specifically what we’ve been looking at in this study,” said Theriault. “So the logperch is a perk.”