Posted on

Artificial light and the decline of salmon smolts

by Conservation Slim

“Slim report”

Spring is here and fishing has been favorable for those who drove eastward to Pyramid Lake and especially the timing of our annual club fish-out which could not have been any better planned. My tenth year at the lake with the club and we all agreed that this is the grandest year for the fish and fishing as the bays filled with thousands of large trout all in spawning mode moving past our feet by the dozens and all day long.

The old pro’s in our group said the (4) of them conservatively landed over 500 fish that 6 days sitting on the platform chair.  I enjoyed all the friends and activity but had to slip away to a south lake beach to be more remote and fish deeper water from shore. Never before have I had multiple double digit fish days and landing more than one fish in the teens in a single day. The unusual thing was the high numbers of fish foul hooked this year. It was more likely your fish was foul hooked than legally hooked and even when you were trying not to set the hook too hard or too soon. Even small midges like the albino wino was hooking the fish in the fins more often than not.

News flash: Pyramid Lake, Pilot Peak fish up to 16 lbs are now being counted as they pass the fish ladder on the Truckee River. The hatchery folks (Lahontan National Fish Hatchery, Gardnerville NV) monitoring the fish as they pass are marking and numbering these spawners. It will be an exciting river to fish once the cutthroat trout establish themselves again.

An interesting article appeared in fishreport@fishbio.com on the subject of artificial lights along the Sacramento River and how that affects the salmon smolts as they travel at night downstream to the sea. Predators like the striped and black bass use the added light to spot and feed on the smolts which in the distant past would use the dark nights to slip past these predators.  Full article can be found at:  https://fishbio.com/field-notes/the-fish-report/smolt-spotlight-effects-artificial-lighting-salmon-survival

Locally, as was in the local news and ‘Slim’ was not aware of the coho salmon planting into Scott Creek from our local Kingfisher Flat hatchery in Swanton. NOAA has control of this and has their own crew of workers. The low rivers was the reason to release the fish early. These fish survived the wildfire that heavily damaged the hatchery infrastructure and killed about half of last years hatched fish. The hatchery access was burned and destroyed (2 bridges over the creek). There is still no timeline as to the replacement of bridges and plumbing and tanks.  (Photo taken years ago of salmon smolts entering salt water for the first time, the jumping part ended when they started adding salt to the water in the tanker trucks prior to being driven to the harbor from the Feather River Hatchery).