Fisheries and Oceans Canada is working with the aquaculture Industry with the goal of helping it operate in a sustainable and responsible way.
This team of research technicians is heading to an area where salmon are raised in fish pens that are suspended in the open water. They’re going to retrieve data from an array of acoustic monitoring receivers that have been strategically placed along the South Coast of Newfoundland.
These submerged receivers are picking up acoustic signals from once caged Atlantic salmon that have been specially tagged and released into the wild as part of a three-year study to see where fish go when they escape an aquaculture net pen.
As part of the Program for Aquaculture Regulatory Research, this project is feeding into a larger research initiative in Atlantic Canada that is exploring the genetic interactions between wild and farmed salmon in efforts to better understand the risks and improve the overall sustainability of the industry. Dr. Dounia Hamoutene is the project leader.
What we do is we simulate escapes, we have a certain number of fish that we tag and then, we have deployed receivers in some strategic areas, and we basically detect whether they went through that area or not.
Curtis Pennell explains how the salmon are tagged and released.
We’ll start off and we’ll put the fish in an anesthetic bath, once the fish loses its’ equilibrium, we’ll take him up, we’ll do weights and measurements. And we’re going to make a small incision – 2 to 3 centimeters, on the belly of the fish. We’re going to insert an acoustic tag. And once that’s inserted, we’re going to close the incision with two sutures. Take a scale sample for aging, we’ll take a small fin clip for DNA analysis. We’re going to stick an external tag on the back of the fish that will identify the fish if someone captures it. And then we’re going to leave the fish to recover for a few minutes before we release him back into the wild.
The particular question we are answering is, if you have an escape in the environment around a fin fish cage operation, where would the escapees go, how fast, would they behave differently in different seasons, are they reaching the rivers, how fast are they reaching them? Can we recapture them? Are we seeing different behaviors because of different sizes?
What we are concerned about is that when a farmed escapee interbreeds with the wild population that you will change the genetic makeup of the progeny and therefore you might alter the adaptation of this future progeny to the river. It might impact their ability then to be successful within this river environment.
You know, we’re tagging different sizes of fish and the other aspect as well is we’re doing that at different times of year because you have a seasonal component in the behavior of the fish therefore we have to understand you know if the escapees are behaving differently in the spring versus the winter.
And the results of this research will feed into decisions on how best to manage the industry.
In the management of the industry, we focus on escape prevention…
Geoff Perry, Director of Aquaculture Management in Newfoundland and Labrador, explains:
Well, if we can understand where fish go when they escape from farms we can target mitigation measures or recapture measures. So we might be able to develop fisheries measures that will be targeted at removing escaped fish from the environment.
This project is important to the Canadian public because the more we understand about the effect of an industry on the environment itself the more successful we can make this industry. This has to be successful on all level, it has to be successful commercially but it has to be successful within the environment it is set in.