Observation The mouth of the Klamath River morphology is changing and not allowing the ocean tides to push into the estuary. Basically the river level is dropping because of the drought. This has made the mouth really long and narrow, until it has essentially became parallel with the ocean.
It is making it like a lake in the estuary, without any tidal movement. We noticed that the tide gauge at Requa had lost it tidal (sinusoidal) signature, instead reading a more constant height. Normally we would have a four feet tidal change. Now we are getting less then a foot. Other evidence of minimal tidal activity include the low levels of conductivity measured by Yurok Tribe's monitoring program. Less salt coming in from the ocean is causing a decrease in conductivity.
The change in the river is a big problem for fish. We have not only fewer fish getting into the river, we also suspect there are fewer salmon wanting to enter the river, because of the warmer estuary temperatures. The estuary of the Klamath is where chinook salmon spend days getting acclimated to the river. Now it is so narrow that they have a hard time even breaching the mouth of the river. This has made easy feeding grounds for the sea lions and is making it harder for chinook to enter the river. We could tell the salmon were having a hard time, due to the abrasions on their stomachs from the shallows, and also the increase in seal bites on salmon we caught.
We use the mouth of the Klamath for subsistence and commercial fishing. We know that there are fewer salmon entering the river, because of the low catch in our nets in the estuary. There was only one or two days of a salmon run for subsistence. Some people missed the opportunity and never had another good opportunity.
Sources: Paul Van Mechelen, Koiya Tuttle, Micah Gibson; Joe Hostler
Photos by Joe Hostler:
September 29, 2015 showing the river channel heading south. (before)
October 6, 2015 showing where the river channel breech to the ocean. (after)
Here's a weblink to Yurok Tribe Environmental Program real-time estuary gage
Mouth of Klamath River, 10-6-15 by Joe Hostler (Before)
Mouth of Klamath River, 9-29-15 by Joe Hostler (After)