Picture of the week

The struggle to spawn

A chinook salmon trying to leap over the gate of the fish ladder entrance of the Nimbus Dam fish hatchery on the American River. 

I photographed these magnificent fish the day before the hatchery spawning operations began.  At this point, many salmon had gathered at the gates waiting to fullfill the final effort of their journey up the American River from the Pacific Ocean. The fish hatchery at Nimbus Dam opened its gates for the fish ladder on 11/4 to allow the salmon to enter the holding pond area for the spawning.  Each fall the hatchery processes thousands of salmon for their eggs, fertilizing them from the male's sperm, incubating the eggs, raising the resultant fry, and ultimately releasing them back to the river the following year.

While processing the photos taken here, I noticed one salmon still has a fish hook with a piece of line stuck in its back, behind its dorsal fin.  After observing enough fisherman behaving badly in an illegal technique to try to snag a salmon, this is not surprising.  Apparently this salmon survived that snag attempt, and has made it this far to reach its end just inside this last gate.  You can see this fish in the fourth image below.

After noticing the number of salmon below the waters surface, and at close proximity, I decide to build a "salmon cam" to photograph them underwater.   Using a GoPro Hero Sessions 4 as the basis, I contructed an assembly for holding the camera in a stable position against the water's current.  A cord is attached to the unit in order to allow it to be towed against the current.  See the image to the right.  Some captures from the "salmon cam" are shown below.  I am not sure what more will come from this, as the relatively low light and murky water visibility limits the quality of captures I have been able to achieve within the performance parameters of the GoPro.

As an update, I have an improved model "salmon cam" that sits on the bottom, as placed there using my fishing waders.  This gives the advantage of a more stable position that I can also more precisely control the angle.  You can see a video recently posted of the results here.