Monique Keiran: Everything We Shoot Affects Marine Life

Southern resident killer whales are among the most contaminated marine mammals in the world.

Southern resident killer whales are among the most contaminated marine mammals in the world.

They are highly contaminated with polychlorinated biphenyls (PCBs) in particular, which affect whales’ physical and brain development, their immune system and their reproductive health.

Ocean Wise and the Environmental Law Center at the University of Victoria reported in 2020 and 2019, respectively, that of 51 sites sampled along the coast, Victoria Harbor contains the highest concentrations of mercury and toxins such as PCBs, dioxins, flame retardants. and plastic stabilizers. The results are based on data from Ocean Wise’s PollutionTracker, a tool that monitors contaminants in the marine environment along the British Columbia coast.

Although our harbor is not considered a critical habitat for killer whales, concentrations of toxins can affect other species. These include some endangered Pacific salmon that the endangered killer whale feeds on. In addition, some salmon can feed on other species that spend part of their life in our port.

I have seen signs of herring running down the gorge, and each year volunteers count the coho that return to spawn in Colquitz Creek. Crabs, shrimps, oysters and other invertebrates, as well as fish can also take shelter in our port.

Adult chum eat fish, molluscs, and other marine invertebrates. Chinook salmon eat insects and crustaceans when they are young and other fish as they grow and grow.

In 2016, Seattle-area researchers found over-the-counter and prescription drugs, cocaine, and other illicit drugs in the tissues of young chinook in Puget Sound. The waters of the estuary near the outlets of wastewater treatment plants in the region were cocktails of more than 80 drugs and personal care products.

To find out what the drugs might do for the fish, the researchers undertook another study. They regularly fed fish feed treated with chemicals to the same levels found in the estuaries of Puget Sound.

The results, reported in the journal Environmental Pollution in 2018, were not good. The fish grew more slowly, and their metabolisms were so disrupted that they appeared to be hungry. Blood tests showed that the disturbance continued long after the chemical diet had ceased.

The response has been particularly pronounced in chinook salmon, a species on which orcas residing in the south depend.

What is found in inland waters would also affect the fish swimming there. For example, Czech researchers recently found that brown trout stored for eight weeks in water containing traces of methamphetamine similar to levels found in European rivers downstream from cities showed signs of methamphetamine addiction.

When the researchers transferred the fish to uncontaminated water and offered the choice between clean water or water containing methamphetamine, the trout exposed to methamphetamine chose water containing drugs – a behavior that suggests an addiction.

The fish were also less active than the trout that had never taken the drug. Researchers found evidence of the drug in the brains of fish for up to 10 days after stopping methamphetamine dosing.

Methamphetamine and cocaine may not build up in fish tissue or move up the food chain like PCBs and similar toxins do. Addiction, however, could cause fish to congregate near sewage outlets in search of solutions, as well as disrupting their natural lifestyles and disrupting the health of the population.

All Pacific salmon start their lives in freshwater. Coho spend at least one winter in freshwater before moving to the ocean, while sockeye and rainbow trout spend one to three years in rivers, streams, and lakes before heading out. towards salt water.

Chinook salmon vary, with some moving to the ocean in the weeks after hatching and others remaining in freshwater for up to two winters.

Most of the rivers in southern British Columbia flow through towns and villages that discharge sewage and carry loads of chemicals and drugs.

This means that many BC salmon are exposed at a young age to anything we shoot, whether it’s what we throw, vomit, or flush our toilet. And if the salmon is exposed, the southern resident killer whales are likely affected, either directly or indirectly.

The Capital Regional District’s new wastewater treatment plant, which began operating in December, provides tertiary treatment before the wastewater is dumped two kilometers into the strait. Tertiary treatment is one of the highest levels of contaminant reduction process and is used to further reduce substances such as metals, organic chemicals, and nutrients such as phosphorus and nitrogen.

Depending on the specific processes in place at a facility, it can also reduce the amount of pharmaceutical and personal care products in wastewater.

It would be interesting to know how this helps reduce the stew of drugs and chemicals that salmon and killer whales in the area are exposed to.

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