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salmonid
03-08-2016, 07:21 PM
Fall run Chinook on the Eel river had a tough year with the drought and water diversions from the river. Some of them went blind in the low warm water.


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Recent high tides and brief mid-September rains gave some Eel River salmon a fleeting chance to move closer to their spawning grounds. But a lack of adequate flows on the river is causing many fish to fall ill as they crowd within small pools for weeks at a time, according to a recent survey by the Eel River Recovery Project.


In an email to the Times-Standard, Wiyot Tribe Natural Resources Director Stephen Kullmann said the low-flow conditions on the Eel River are exposing these salmon to disease, predation, and poor quality water as they await adequate flows to move upriver.



“Agencies need to emphasize restoration projects in the estuary to ensure quality holding habitat,” he wrote. “Furthermore, water diversions of all types urgently need to be addressed to return Eel River flows to natural levels.”

http://www.times-standard.com/article/NJ/20151027/NEWS/151029830

The UCD report analyzing a few fish came out last week; following is a snippet. I hope our lab can get some samples to test genetically, so we can monitor this going forward.


Upon necropsy, the eye and brain were the only two tissues presenting gross changes. In 3/3 fish, opacity of the lens consistent with cataracts associated with digenetic trematodes (eye flukes) encysted metacercaria were observed (Figure 1). White nodules associated with encysted metacercaria were observed in superficial periocular tissues of 3/3 fish (Figure 1). In 3/3 fish, petechial hemorrhages were observed in the central nervous system, specifically in the brain (optic lobes, cerebellum) and spinal cord (Figure 2). Few protozoans consistent with Trichodina spp. were observed on skin scrapes of 1/3 fish.

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