This week I was able to get some pictures of kokanee salmon during their annual spawning run up the tributary to a local lake. 

Kokanee (Oncorhynchus nerka) are the landlocked form of sockeye salmon, kind of similar to landlocked atlantic salmon found in many northeastern U.S. lakes.  Native forms of kokanee are found in many lakes that currently have, or have had runs of sockeye salmon from the Pacific Ocean.  It is believed that these native stocks arose from sockeye salmon offspring that stayed in inland lakes after hatching, instead of returning to the ocean. 

But the kokanee that most people are probably familiar with are those that have been stocked in inland lakes by fish and game departments to provide additional fishing opportunities.  This is the case with the fish I was observing this past week. 

One of the coolest things about these fish is that they take on an amazing red color in preparation for spawning, as opposed to the silvery color they possess prior to spawning.  Their color is such that one can walk along the shoreline of a kokanee spawning river and easily see each spawning fish. 

Unlike Atlantic salmon, species of Pacific salmon are semelparous, which means that they spawn once and die.  We observed thousands of kokanee spawning in the stream, as well as a number of dead carcasses of fish that had expended all of their energy spawning, and died.  There were tons of raccoon tracks and bird tracks on the shoreline, and at one point, there was a place along the shore where a mink had apparently pulled a number of kokanee from the river and eaten their heads, which contain the highest energy content in the fish’s body.

Kokanee are a popular sportfish and play a significant role in cycling nutrients in the ecosystems they inhabit.  They consume zooplankton and fish in the lake environment, spawn in the streams and die, where animals and insects consume them, excrete nutrients, many of which return to the aquatic ecosystem, feeding phytoplankton, which feed zooplankton…..and the cycle continues.  And aside from that, they’re fun to fish for and pretty cool to check out during the spawning run!

The Missouri Department of Conservation is funding a 3 year research project investigating the spawning habits and movement patterns of catfish in the Missouri River and its tributaries.  While adequate data exists for other game species, little is known about catfish spawning ecology.  This research could provide fisheries managers with essential information needed to make recommendations about season, length and bag limits, which would likely result in more and bigger catfish for Missouri anglers.  The DOC is considering a number of regulation options to provide a better fishery, but plans to wait on research results before making regulation decisions.

Read more about the catfish research going on, and the options the DOC is pursuing here. 

An access road to Washington’s William O. Douglas wilderness area washed out during flows this year, and won’t open any time soon due to concerns for endangered bull trout living in and near the washed out road bed.  Numerous juvenile bull trout were found in water at the road crossing, and therefore temporary re-opening will have to wait.

Personally, I would suspect that juvenile bull trout would do okay with a few vehicles crossing the road (they can, in fact, swim out of the way…..and they’re darn good at it too.  Try netting a juvenile trout sometime!), which makes me wonder if this is more of a political decision than a practical one.  However, the report states that bull trout spawning time is nearing.  If this is in fact the case, driving through the stream would likely stir up sediment harmful to egg survival in bull trout redds. 

Needless to say, the road is closed, and won’t be open for some time.  I’m sure some locals are frustrated by the access constraints, while other people are glad to see officials keeping a watchful eye on the fish.   

A marina owner on Idaho’s Lake Pend Oreille reportedly destroyed kokanee spawning habitat, and killed a number of the fish in the gravel while attempting to place pilings in the lake as part of an unpermitted expansion project. 

The owner has hired a kokanee expert and is planning to somehow vacuum out the silt and sawdust that was deposited in the area so that the spawning beds are in suitable condition for this fall’s kokanee spawn.

Kokanee are a landlocked form of sockeye salmon, and are the driving force behind an estimated $17 million fishery in the northern Idaho lake.  The area where the marina expansion took place is known as an important spawning area for the fish because of adequate spawning gravel and an upwelling of cool, oxygenated water.

The damage to the kokanee population was estimated at $1.4 million, but the marina owner was only fined $2,500 for completing the project without a permit.  

Since I don’t know the details behind the cost estimate of the kokanee population loss, or whether the loss at this life stage will have a significant effect on the population when this age class of fish reaches adulthood (mortality factors sometimes compensate at other life stages),  I can not comment on its validity.  However, a $2,500 fine seems like a far cry from the actual cost to the kokanee population and its value to the lake’s recreational sport fishery. 

The marina owner plans to cover all the costs of the spawning habitat restoration, realizing that he unknowingly damaged the fish population, and a good number of his clients are anglers.

See the story in the local news   

Cutthroat trout, native to the Western U.S., are spring spawners that often ascend small tributaries to construct redds (egg nests) and lay their eggs.  Upon entering their spawning grounds, male and female pair up and swim side by side.  The female digs a pocket in the gravel to deposit eggs by turning sideways and ‘cutting’ at the gravel with sharp movements of her tail.  Pictured below is a female in the act of cutting, or building her redd.

This picture was taken by a fellow researcher in our lab, who is investigating the spawning ecology of Bonneville cuttroat trout in northern Utah.  Notice the beautiful coloration and spotting pattern on this fish.  Also, check out the red/orange slash on the underside of the jaw and operculum, which is where they get the name ‘cutthroat’.  We’ve just about passed the peak spawning season in most of the tribs, but in some areas cutthroats are still ascending from the main stem of the river to spawn.  Many of these tributaries have barely enough water for the fish to swim up, let alone spawn.  I noticed a large group of fish spawning the other day in water so shallow, their backs were halfway out of the water!  Check out a few more pics of this spawning female.