4 ms·

The Mystery of the Missing Sockeye

14 points by dnetesn 6y ago

rob74 6y ago
+1 for the classic Sherlock Holmes-style title. Unfortunately, unlike the original, the mystery is not solved by the end of the story - nor is it likely that they will find a single culprit... However, the top illustration for the article is not really well chosen, because it shows "spawning-phase" salmon, which always look (and are) unhealthy, because they are genetically programmed to die off after spawning. To quote Wikipedia: > Highly elevated cortisol levels mediate the post-spawning death of semelparous Oncorhynchus Pacific salmon by causing tissue degeneration, suppressing the immune system, and impairing various homeostatic mechanisms. After swimming for such a long distance, salmon expend all of their energy on reproduction. One of the key factors in salmon rapid senescence is that these fish do not feed during reproduction so body weight is extremely reduced.
steve_adams_86 6y ago
This one is close to my heart. I have the impression here that the fish farm vector is being grossly understated. The research didn’t really leave much of a mystery at all; the data was alarmingly clear, but the federal leader at the time was quite notorious for muzzling scientists and he did just that. Especially when it came to the environment. Further, we have evidence now that hatcheries impede salmon genetics severely enough to a) make them more vulnerable to disease and b) make them less adept at navigating their spawning waters, which can vary considerably. Hatcheries are an established institution though, just like salmon farms are, and they aren’t going anywhere soon. It’ll require irrefutable evidence to get anyone at DFO to lift a finger. I’m also unsure of Miller-Saunders is focused on this matter at all, hence it’s not mentioned here. The final glaring issue is that our rivers are warming dramatically, water levels much lower by summer, and oxygen content is way, way too low. Disease levels increase and spawning tributaries all along the rivers virtually disappear. One can subscribe to the weekly emails from DFO which outline regulation and conditions around the spawning runs throughout summer, and the historical data right in those emails regarding water quality of our major rivers is very alarming. We know that widespread deforestation has contributed to more flood and dry patterns throughout our watersheds. With less established forests to retain water and earlier/faster thaws, we get water dumping out of the watershed way too fast in spring, leaving too little by late summer. The salmon are sometimes saved by a single rainy week in summer, otherwise trapped by low water levels. It’s common to come across areas of the river where the fish were severely bottlenecked and there are absurd numbers of dead fish in single locations. It’s normal to see a LOT of dead fish, but in these cases it’s considerably higher numbers. They simply couldn’t go anywhere. These factors alone are huge. I’m not sure Miller-Saunders considers it a mystery, but I can’t speak for her. I do know she felt very, very strongly about her research around the farms and she pushed hard to get DFO to pay attention. She knew it was highly relevant.

14 points by dnetesn 6y ago

+1 for the classic Sherlock Holmes-style title. Unfortunately, unlike the original, the mystery is not solved by the end of the story - nor is it likely that they will find a single culprit... However, the top illustration for the article is not really well chosen, because it shows "spawning-phase" salmon, which always look (and are) unhealthy, because they are genetically programmed to die off after spawning. To quote Wikipedia: > Highly elevated cortisol levels mediate the post-spawning death of semelparous Oncorhynchus Pacific salmon by causing tissue degeneration, suppressing the immune system, and impairing various homeostatic mechanisms. After swimming for such a long distance, salmon expend all of their energy on reproduction. One of the key factors in salmon rapid senescence is that these fish do not feed during reproduction so body weight is extremely reduced.

steve_adams_86 6y ago

This one is close to my heart. I have the impression here that the fish farm vector is being grossly understated. The research didn’t really leave much of a mystery at all; the data was alarmingly clear, but the federal leader at the time was quite notorious for muzzling scientists and he did just that. Especially when it came to the environment. Further, we have evidence now that hatcheries impede salmon genetics severely enough to a) make them more vulnerable to disease and b) make them less adept at navigating their spawning waters, which can vary considerably. Hatcheries are an established institution though, just like salmon farms are, and they aren’t going anywhere soon. It’ll require irrefutable evidence to get anyone at DFO to lift a finger. I’m also unsure of Miller-Saunders is focused on this matter at all, hence it’s not mentioned here. The final glaring issue is that our rivers are warming dramatically, water levels much lower by summer, and oxygen content is way, way too low. Disease levels increase and spawning tributaries all along the rivers virtually disappear. One can subscribe to the weekly emails from DFO which outline regulation and conditions around the spawning runs throughout summer, and the historical data right in those emails regarding water quality of our major rivers is very alarming. We know that widespread deforestation has contributed to more flood and dry patterns throughout our watersheds. With less established forests to retain water and earlier/faster thaws, we get water dumping out of the watershed way too fast in spring, leaving too little by late summer. The salmon are sometimes saved by a single rainy week in summer, otherwise trapped by low water levels. It’s common to come across areas of the river where the fish were severely bottlenecked and there are absurd numbers of dead fish in single locations. It’s normal to see a LOT of dead fish, but in these cases it’s considerably higher numbers. They simply couldn’t go anywhere. These factors alone are huge. I’m not sure Miller-Saunders considers it a mystery, but I can’t speak for her. I do know she felt very, very strongly about her research around the farms and she pushed hard to get DFO to pay attention. She knew it was highly relevant.