THE ISSUE
Overexploitation continues to be a significant contributor to biodiversity loss in Canada, and it is not slowing down. Logging, overfishing, mining, and hunting each contribute to the steep decline of species numbers.
The 1992 collapse of the cod fisheries in Newfoundland is a stark reminder of the interconnectedness of ecosystems and of our dependence on them. This collapse affected thousands of people culturally and economically. Yet, on June 26, 2024, Fisheries and Oceans Canada re-opened the practice, despite the warnings of conservation groups.
Overall, 56% of freshwater fish species are at risk in Canada. Some are not around at all anymore, like the Brook Trout that used to be plentiful in Ontario.
In the forestry industry, over a million acres are clear cut annually. The federal government insists this is a carbon-neutral affair, though that remains contested.
Mining includes extracting oil, gas, metals, and minerals across thousands of active projects in Canada. Most recently, a mine for lithium and copper was approved in the Province of Yukon in the middle of caribou habitat . Despite scientific and Indigenous opposition, the Canadian government approved the Environmental Assessment process . This is consistent with decisions from the past. Over 95% of mining projects within caribou habitat have been approved since the end of the 20th century.
An additional example of overexploitation is unregulated hunting of large carnivores, which can lead to ecosystem decline. Wolves, a keystone species, were once eradicated in Yellowstone National Park due to hunting. As a result, sounds of certain birds were no longer heard, coyotes rose tremendously in numbers, and beaver populations rapidly declined. When these predators were reintroduced, the positive effects extended to species of aspen and willow that were previously overconsumed by unchecked ungulates. Recent research suggests that wolves play a role in maintaining healthy ungulate populations that can better withstand climate-related changes.
The Cause
It is not a single kind of overexploitation that affects biodiversity. We are taking from every nook and cranny, in oceans and on land. We are not giving nature a chance to rebound.
This is possible due to a lack of regulation. Certain Canadian fisheries are under regulated , and research has shown policies that are in place are often not followed. Reports from 2022 show that the Department of Fisheries and Oceans is “falling short when it comes to protecting endangered species.” Government policies have consistently favoured extractive industries over long-term sustainable management.
The Impact
Biodiversity has drastically been reduced due to overexploitation. Let’s take the cod example again.
When there isn’t a lot of cod, Sprite flourishes. If there’s a lot of sprat, you see a decline in zooplankton. Less zooplankton means more phytoplankton. More phytoplankton results in higher nutrient concentrations in our oceans and
consequently less oxygen. There is also a negative impact on “carbon storage, water filtration, and buffers for flooding are compromised.”
Chain reactions like this occur throughout the natural world and can result in the loss of species after species.
Lands and water are connected. What happens to one has an impact on the other. British Columbia’s rare “inland
temperate rainforest supports at-risk fish species like chinook salmon, bull trout and sturgeon”, yet is at dire risk of disappearing within the next couple of decades.
The rivers that create habitat for these diverse fish species are negatively impacted by the overharvesting of forests
in multiple ways, including increases in river water temperatures and loss of sediment (Cunningham et al.,
2023). Overexploitation via logging leads to a key cause of biodiversity decline which is ultimately that of habitat loss.
Solutions
The management of fisheries should not be done in a silo. By making plans public, there is greater accountability. We can demand yearly updates depending on the current status, increase fines for illegal and unregulated fishing, and set limits that take research into consideration. Even keystone species can come back.
They can increase their numbers if the conditions are right and if humans take a step back. For a long time, sea otters were ubiquitous in the coastal waters of British Columbia. By the end of the 1800s, they went extinct on the west coast of Canada due to overharvesting for their furs. To reverse this, 89 otters were reintroduced to British Columbia in the 1960’s. Through both federal and provincial protection, their numbers continue to increase.
As a keystone species, sea otters have a tremendous effect on the environment around them. Sea otters eat sea urchins, which means the kelp forests can flourish. If given the chance, an ecosystem can keep itself in check.
Humpback whales have seen a similar comeback after whaling would have led them to extinction in the 19th century. Their numbers in the Atlantic continue to increase thanks to enhanced regulation through both the Fisheries Act and the Species at Risk Act.
