Den mother
A face only a mother could love
What is striped, grows to be five feet long and has big chomper teeth all over the roof of its mouth? The Atlantic wolffish.
The first extended recreational groundfish fishery runs until August 6, and Memorial University PHD student Emilie Novaczek wants all you fisher people out on the water to take note of what you bring in on your line.
In particular, if you catch an Atlantic wolffish, Novaczek asks that you take note of your location and get in touch with her. And more importantly, she asks that you gently return any wolffish to the water.
This may be easier said than done due to the aforementioned teeth. Novaczek definitely does not recommend giving your new fish friend a cuddle as he may mistake your hand for a sea urchin, his favourite menu item.
“I suggest maybe taking a cutoff broom handle in the boat with you,” said Novaczek. “That way you can put it in between his teeth while you get the hook out.”
There are three types of wolffish: spotted, northern and striped.
The first two types are threatened and the third, the one that most interests Novaczek, is of special concern. In partnership with the Department of Fisheries and Oceans (DFO), Novaczek has been studying striped or Atlantic wolffish in Conception Bay since 2014.
“Wolffish are designated as a species of special concern under the Canadian Species at Risk Act — one of very few marine fish that are protected under the act,” said Novaczek, whose supervisors are Drs. Rodolphe Devillers and Evan Edinger. “But little was known about their habitat to inform a management plan.”
“In 2014 and 2015 we mapped Atlantic wolffish habitat in Conception Bay, with detailed characterization of some dens near Bauline. The dens are really important for wolffish — they pair, spawn and guard their eggs in these dens. Feeding debris at the den openings indicates they are also foraging in this habitat.”
With the help of 16 hydrophones placed in Conception Bay by DFO, Novaczek continues to map the striped (Atlantic) wolfish habitat.
“We have better maps of Mars and Venus than we do of the seafloor. Yet it covers 70 per cent of the planet and we rely on the ocean for food, shipping, recreation, and much more,” said Novaczek, who completed an undergrad honours thesis with the Seaflower Marine Protected Area in Colombia before coming to Memorial. “It was in Colombia that I learned the critical use of maps as a management tool. We need to know about habitat in order to protect a species.”
Every time each of the 34 tagged wolffish pass by a hydrophone in Conception Bay, their presence is recorded and at the end of each season DFO retrieves the hydrophones to track the tagged wolffish. That information, combined with the mapping Novaczek and her team have completed with the help of DFO divers and the use of drop cameras, provide a picture of what the ocean floor looks like where the wolffish spend most of their time. It turns out that a wolffish’s favourite areas have big hard boulders, 30-90 degree sheer face and lots and lots of sea urchins. Armed with this information Novaczek investigates areas of the sea floor with similar qualities and see if there are wolfish or wolffish dens there.
“We do predictive mapping so we know where we should go next and to determine what areas should be better studied or conserved,” said Novaczek.
“DFO has done a great job at getting information about the wolfish out to harvesters. But there is so much more research to be done. We assumed Bauline was a hot spot, but Cape St. Francis, which is difficult to map due to rough conditions, may have even more dens. We’re still working with limited information, so I’d love for anyone who spots a wolfish during the food fishery to send me an email at enovaczek@mun.ca.”