By Tim Jardine
NOTE: This is a guest article written by Dr Tim Jardine from the School of Environment and Sustainability and Toxicology Centre at the University of Saskatchewan.
So I’ve heard it said. And there’s some truth to it. Unless you’re camped on the top of a mountain peak, you’re going to be downstream of someone, and your water supply will be vulnerable to any of their potential misdeeds. But it’s also fair to say that some are more downstream than others. In particular, deltas.
Deltas occur in low-lying areas when a swiftly flowing river meets a larger body of water. On the coasts, we recognize these deltas in myth and lore – the Nile, the Ganges. Less well known are inland deltas, where rivers meet lakes. In western Canada, we have three big ones – the Peace-Athabasca, the Saskatchewan and the Slave.
Deltas get the best and worst of what happens upstream. Prior to human interference, turbulent waters running off the Rocky Mountains rushed into glacial lakes, depositing massive quantities of nutrient-rich sediment. Over the past 10,000 years, this sediment accumulated until it was eventually cut through by the river’s flow, creating a vast network of wetlands, backwaters and side channels, each with its own biochemical and ecological character.
Unsurprisingly, these deltas became wildlife hotspots, and people followed close behind. The numbers are staggering. In the Saskatchewan River Delta alone, more than 100,000 muskrats were harvested each year in the late 1800s. Millions of waterfowl passed through these deltas every fall. Commercial fisheries for sturgeon and walleye provided income and food for local residents.
In the Saskatchewan River Delta alone, more than 100,000 muskrats were harvested each year in the late 1800s. Millions of waterfowl passed through these deltas every fall. Commercial fisheries for sturgeon and walleye provided income and food for local residents.
Yet the past century has not been kind to these deltas. Human populations in their basins have grown to more than 3 million people, each of us with a hunger for food from irrigated crops, thirst for household water and demand for electricity generated from hydropower. Flows through the deltas have declined and become more erratic. There are contaminants in wild food. Wildlife numbers have dropped. The people of the deltas often feel powerless because their voices are not heard.
But there are signs of hope. The Cree, Dene and Metis people in delta communities are sustaining culture through a resurgence of language and on-the-land activities. Knowledge is being handed down to a new generation of delta stewards. Community leaders are pushing for greater accountability from upstream decision-makers, and building capacity to recognize and protect their deltas.
Flows through the deltas have declined and become more erratic. There are contaminants in wild food. Wildlife numbers have dropped.
As scientists, we have responsibilities to ensure that the research underpinning decision-making is sound and includes diverse sources of knowledge. Partner respectfully with delta communities. And step aside when the voices from the deltas need to be heard.
Is anyone listening? We certainly hope so. Working together, these special places may finally get the same respect from outsiders they’ve been given by their local caretakers for generations.
Note: Tim Jardine is an Associate Professor at the School of Environment and Sustainability and Toxicology Centre at the University of Saskatchewan, and a Fellow of the Canadian Rivers Institute. He studies the ecology of rivers in temperate, sub-Arctic and tropical landscapes in eastern Canada, northern Australia, and Brazil, and leads large interdisciplinary projects in Western Canada’s inland river deltas.
Catchment to Coast 