All images courtesy of the Pacific Salmon Ecology and Conservation Laboratory at the University of British Columbia

Student presenters and the broader salmon community recently gathered under the watchful eye of veteran biologist Dr. Scott Hinch for the 19th annual UBC symposium on salmonid migrations, ecology and management. The symposium extensively explored two themes: First, how do salmon fare after encountering marine recreational fisheries? Second, what happens when we upgrade flood control infrastructure in the Fraser Valley that currently blocks the migration of salmon to vital rearing and spawning habitats? The thread running through both is that our assumptions crumble under the scrutiny of this generation’s junior researchers, who are determined to question the status quo, and armed with the latest technology to do so.

The symposium opened with an introduction by Dr. Hinch on a series of timely and novel studies conducted by the Pacific Salmon Ecology and Conservation Laboratory to generate release mortality estimates for chinook and coho salmon from marine recreational fisheries. This research is timely and important because catch-and-release fisheries are expanding in several areas along our coast. In 2023, anglers in South Coast marine recreational fisheries released a record 348,893 chinook salmon. This was due to increased fishing activity, regulations requiring anglers to keep only hatchery-marked fish, and size limits on which salmon could be retained. Preliminary estimates for 2024 are that South Coast sport fishers released over half a million chinook and coho.

This matters because the Department of Fisheries and Oceans builds an estimate of release mortality into the total number of fish that are killed by the recreational sector. The Hinch lab’s studies show that release mortality has previously been significantly underestimated. Dr. Hinch closed his remarks by suggesting that it’s time for our recreational angling management regulations to catch up, urging for a re-evaluation of the practice where anglers release fish that may not survive. Instead, he offered the idea that it may make more sense for anglers to keep what they catch, and stop fishing once they reach their limit.

Next, it was on to grad student and allied researcher presentations on catch and release studies, which revealed that coho are more vulnerable than chinook, smaller fish are more vulnerable than larger fish, females are more vulnerable than males, and all fish are more vulnerable when waters are warm. Though this may sound like common sense, quantifying the effects is largely new information. The takeaway is that a salmon “swimming away strongly” from an interaction with a recreational angler is no indicator that it will survive. For example, during her presentation on metabolic recovery of captured and released coho and chinook salmon, postdoctoral fellow Dr. Jacey C. Van Wert reported that after one hour, coho only made a 30 per cent recovery towards their resting metabolic rate and that depending on the fight, full recovery can take as long as 15 hours. At a minimum, angled salmon may lack the capacity to escape predators when released.

Through four years of study, the lab’s research teams also quantified what types of interactions with anglers cause the most harm. All landing nets break fins, line wraps remove scales, and eye wounds and visible bleeding are almost certain death sentences. To complement the research, the lab released a series of recommendations about how improving handling can reduce mortality. This is information that DFO can act on. As an avid salmon angler in marine waters, I am grateful to these researchers for asking the right questions about our fisheries and providing practical science-based advice that we can move on. For a deeper dive into methodologies and results, download the lab’s final report to the BC Salmon Restoration and Innovation Fund here.

One of the coolest things about academia is its proximity to cutting-edge technology. And is there a place where technology is more important than in the aquatic environments, which are inhospitable to us air breathers? From a small ‘jerk tag’ measuring the acceleration of hooked salmon to the strengthening of key nodes in Canada’s Ocean Tracking Network, a host of innovations and partnerships were on display throughout.

My favourite was the ‘sensorfish,’ a brilliant tool used by MSc student Hollis Kinnard for studying the effects of flood pumps on fish. The last thing researchers who are all too familiar with seeing fish chewed up by flood control infrastructure want to do is chuck a bucket of baby fish into a pump to document what happens. So when at all possible, sensorfish (small chapstick-sized tubes that collect all the data about g-force, pressure and speed,) get tossed in instead. As they move through the pumps, grates, culverts, gates, and rip-rap of the Fraser Valley’s flood management systems, Sensorfish generate information researchers use to estimate the harm these structures cause to our wild salmon.

Sensorfish on the left, victims of flood-control infrastructure on the right

The line running through the morning’s presentation was this: Partnerships were key. While knowing what to measure is crucial, how to measure and manage data is equally vital. Community facilitators (Sport Fishing Institute, Pacific Salmon Foundation, Watershed Watch) and research institutions (Bamfield Marine Station, Ocean Tracking Network) enabled students to conduct effective fieldwork and data collection.

It’s heartening to know that Canadian scientists can access world-leading, made-in-Canada technology and information management systems and that the investments society has made in building durable scientific institutions are ready to help young scientists answer a question like “What happens to coho when it’s released in a marine recreational fishery?”

After lunch, the freshwater team took the stage. Salmon begin and end their lives in streams. In the Lower Mainland, flood control infrastructure is the gatekeeper of far too much critical habitat.

If you are a regular subscriber to our channels, you will know our Connected Waters team has worked tirelessly over the years with municipalities, farmers, First Nations and researchers at the Pacific Salmon Ecology and Conservation Laboratory and other institutions to make life better for salmon. Unfortunately, life in the Fraser Valley for this keystone species is about as tough as it gets.

Lying at the heart of the problem is the 1,700+ km of salmon habitat in the Lower Fraser obstructed by at least 186 pieces of flood control infrastructure. As salmon leave the floodplain, and move into the interior, improperly designed and aging culverts are persistent hurdles to migration. The research teams used tagging, telemetry, and capture and release studies to identify fish passage barriers and determine what types of fixes, whether it was a new pump, a new gate, or a culvert replacement, would reconnect habitat.

It’s stunning to see how much harder we make life for salmon, and a reminder that we should not leave engineers to their own devices. Flood management should be the poster child for the adage ‘do it right the first time,’ because once it’s built, it’s notoriously difficult to remedy. The other confounding issue is jurisdictional. Nobody wants to take responsibility for re-engineering and replacing fish passage barriers. 

The good news is that many of these pieces of flood control infrastructure have reached the end of their life expectancy, and need replacement anyway. Municipalities, First Nations, the Province and the Federal government need to continue negotiating how best to modernize this critical infrastructure–this time with salmon in mind. Kudos to the Pacific Salmon Ecology and Conservation Laboratory research teams for having the right information when it’s needed most.

The 19th annual UBC symposium on salmonid migrations, ecology, and management showcased groundbreaking studies on the impact of marine recreational fisheries and flood management systems on salmon to produce evidence-based and realistic prescriptions for actions we can all take right now to improve their welfare.

Researchers are using innovative technologies to challenge assumptions and overturn the status quo, and cornerstone institutions such as the Bamfield Marine Station, and the Ocean Tracking Network are supporting them. This is hopeful stuff.

In an age that seems to turn its back on the truth, it’s inspiring to meet and listen to the discoveries of the next generation of scientists who are finding novel ways to understand and protect salmon populations.