Lake Stevens kokanee -2015

[Smalma]

With the kokanee derby coming up this Saturday and the previous discussions about the alum treatment early this year I thought some would be interested in my observations about the status of Steven's kokanee this year.

Thanks to an exceptional spring biologically the lake is at least a full month ahead of normal. Currently we are seeing water temperatures that would normally be associated with early to mid-June. In addition there seems to be lots of kokanee and between the advance state of the temperature conditions things should be setup for a successful derby.

With the warmer early spring consistent fishing on Stevens start way earlier than normal. Before mid-April the fishery was in full swing and consistent limits (10 fish) were doable for those anglers that took the time to dial the fishery in. Given the lake temperatures I would have expected that consistent fishing to have begun even a week or 10 days earlier. Over the last decade those conditions typically did not occur until 2 to 6 weeks later or on the average about a month later.

Following the alum treatment in March it was not a surprise to find the lake much clearer than normal. It is the phytoplankton (the greenness in the water) that drive the food chain that supports the lake's kokanee. By late April there was phytoplankton and more importantly daphnia (water fleas) in the water column. It is that daphnia that drives both the growth and nice orange flesh of the kokanee. At that time while there were some large kokanee the vast majority were in the 10 inch range with another group of obviously smaller fish. At this time the kokanee (especially the smaller fish) stomachs were stuffed with daphnia. Though those daphnia were much smaller than normal (it took looking under a scope to be sure that food was indeed daphnia). This small size is important factor for several reasons; 1) it takes a lot more of them to fill the fish's stomach, 2) the larger fish are less effective in filtering them from the water, and 3) the smaller/slower growing daphnia take longer to mature and reproduce. That long time period to reach maturity means that the next generation of daphnia is delayed and over the course of the spring there will be fewer daphnia.

That clearer than normal water conditions (lack of phytoplankton) continues to date. Though to be far the lake is finally "greening-up". As recent as the 4th of May I could still see my release (a yellow seps) at a depth of 20 feet. That distance decreased over the week until yesterday (May 11) the release disappeared at 10 feet. At the same time the daphnia was getting slightly larger. For the kokanee in spite of that month or more jump on the growing season they remain on the average at least 1.5 inches smaller than what we have seen the past several years for similar water temperatures (currently the lake is in the lower 60s).

I expect that the size of this years kokanee to remain below what we have seen the last few years. Generally I saw rapid growth of the kokanee during May and early June after which the fish to move from a growing mode to a more maturing condition. As that transition occurs and growth rates slow I see a physical change in the fish. That change is that the fish's scale become set and are no longer easily shed. This past week I have started seeing some of that transition.

The good news is that there is good numbers of kokanee and within the normal day to day variability that is the major part of the kokanee game things are lining up for a good derby and hopefully and continued good fishing for the rest of the season. Though experience has shown as the fish switch into a more of a maturing mode they become more temperamental; while still very catchable it at times will take significant experimentation to dial them in.

Good luck
Curt

[Toni]

Thank you for your observations. I am going to use some of it for my home lake, Clear. Although, I can't see daphnia.

[Sixgill]

Thanks for the incite. That's good information and it supports what I've been seeing.

[Smalma]

Well another Stevens kokanee derby is in the book and from the reports sounds like another great event. Congrats to all the winners, the organizers, and sponsors!

This was year 6 of the derby and it occurs to me that the results would provide some insight into the status of this year's population. While I don't have access to the number of anglers or number of fish caught we do know the largest kokanee and the weight of the largest 10 fish limit.

In 2010 the winning kokanee weighted 1.26# and the largest 10 fish limit weighed 8.46#.

In 2011 the winning kokanee weighted 1.61# and the largest 10 fish limit weighted 9.93#.

In 2012 the winning kokanee weighted 1.43# and the largest 10 fish limit weighted 10.51#.

In 2013 the winning kokanee weighted 1.68# and the largest 10 fish limit weighted 12.54#.

In 2014 the winning kokanee weighted 1.49# and the largest 10 fish limit weighted 10.15#.

The reports are that this year's winning fish weighted 0.86# and the largest limit weighted 6.06#. Clearly the number of large fish and average size this year are well below average; given the warm and extend spring one would have hoped to have seen larger fish.

Curt

[Smalma]

The odd-ball season continues on Stevens.

After a week of warm weather including a couple days of 80 degree temperatures the lake surface temperature has increased until this morning it was 68 degrees. To my surprise in spite of the increased temperatures the water clarity actually increased since last week - could see my release this morning down to 15 feet and a corresponding decrease in phytoplankton in the water. Not too surprising the number of daphnia appears to be down and the individuals are small. Few of the kokanee that I cleaned this week had full stomachs and those with the fullest stomachs had been eating mostly chironomids. Again a bit out of the norm.

Fishing remains good though for some reason the fish seem more scattered than normal; both in the distribution across the surface lake and vertically. The consistent fishing is moving deeper and the kokanee as often the case are finicky with the hot depth, location, and even presentation seeming to change daily and even hourly; at least for me. At least for me consistent catches have required experimentation and the willingness to adjust on the fly. Though the "professionals" seem to have things pretty consistently dialed in.

Wonder what the rest of the Steven's regulars are finding.

Curt

[Toni]

I saw a picture on Facebook that blurock's customers caught a brown bullhead in 150 foot of water 10 foot down, trolling. Is that normal?

[Smalma]

Toni-

A brown bullhead while trolling for kokanee can hardly be considered "normal". However that is the second one that I have heard of this year and typically hear of several being caught every year from Stevens. I think in the last decade I have caught two. I suspect that those accidental "cats" are out over deep water feeding on chironomids just like some of the of the kokanee.

While the sample size is small it appears most are caught during the early morning or on "gray" days.

Curt

[Smalma]

Another update on my favorite kokanee fishery. Fished this morning (6/8) and found that the water temperature at 72 degree - 4 or5 degrees warmer than the end of last week. Given the weather for last few days that warmer water was no surprise. Much like in late May with the warmer water temperature the visibility this morning was greater than last week; could see my sep release at 15 feet.

The fishing remains good though the numbers of larger fish (greater than 13 inches) seems to be down (at least for this angler). The average fish is about 11.5 inches and are good condition. The fish seem to be scattered in both lake locations and depth. Not marking large schools but seeing small bunches from the mid-20s to mid 60s with the best biting fishing being found at different depths on various days and at times from hour to hour.

While many feel that there are more fish in the lake this year I'm not sure that the fishing is a lot better than any of the previous 5 years. At least measured as the average time it takes to catch 10 fish limits for those that have the fishery "dialed in". I think that may be due to the smaller average size of the fish this year; I have often noted that larger fish tend to be more aggressive (easier to get to bite and often with solid hook-ups per bite).

I expect the fishing to remain good for the rest of the summer though the average size will continue to be smaller than normal. On Stevens if is often the case that success is dependent on the angler being able to solve the daily fishing puzzle. To do so typically requires constant experimentation in gear, color, depth, scent, etc. and this year's fishing hasn't been an exception.

Good luck
Curt

[Steelheadin360]

As the thermocline moves down we have started picking up bigger fish. Out of 52 fish on Saturday the Average fish was 12.5-13" and ten fish were over 14". including a 15" fish that came from 55' down. Like any other Kokanee Lake, Lake Stevens tends to go in cycles. And with the over abundance of fish (I have never seen so many fish on Stevens) we should expect smaller Kokes. In any other Kokanee lake I have fished the bigger fish will hang out under the smaller ones. And with the large number of small fish it has taken longer for the water to warm enough for the big boys to want to bite.

One point I have also seen this year with the Alum treatments. Feed is down but the can also be linked with the early warm up of the lake and the low oxygen conditions. Also, with the treatments happening right before the smolts are planted in the proceeding years, it can cause the young fish to be stunted and not allow for proper food intake during their first year of life. This years plantings should have plenty of chow. And with the smolt die off last year during the summer I was wondering how it was going to effect the size of the fish this year


We are planning to schedule a round table discussion about the future of the Lake this fall. Wa Lakes members will be notified.

[Smalma]

Zack -
Sounds like a good day on Stevens! Good luck with the Skagit sockeye.

I guess it is now official- I'm not much of a kokanee fisher and know little about Stevens and its kokanee and their management. Folks may wish to ignore my previous posts on this thread.

Curt

[Smalma]

Zach -
I'll watch for notification of the round table discussion and would like very much to participate in the discussions.

Since the last post I have been out 4 more times and paid careful attention to the size of the fish caught. Fished 3 times by myself and once with a friend. As you pointed out once the fish start moving deeper the fish larger fish are often found deeper. Since the middle of May I have targeted my fishing on the deepest groups of biting fish I can find. While that sometimes results in lower catch rates experience has shown that the average size sometimes can be larger.

Of the 50 fish caught in those 4 trips more than 1/2 half came from 50 feet or deeper. The 3 largest fish were just at or just under 13 inches; another 7 or 8 were 12 1/2 inchers. As has been the case for the last month the average size was right at 11 1/2 inches. Had more fish under 11 1/2 inches than over. While not the impressive catch that you had in talking with some of the regulars on the lake the sizes In my catch were typically of what most were catch.

The last year that I caught kokanee these smaller size was 7 or 8 years ago. The time it took me to catch a 10 fish limit then was very similar to the time it is taking this year. Though to be fair I'm probably become a little more effective in catch them and of course back then we were limited to 1 rod. That would lend support to my idea that the size of this year's fish is likely more a result of reduced food abundance than higher fish abundance.

BTW As with most Washington lakes kokanee planted in Stevens are not released as "smolts" but rather young of the year fry which typically quite small (1.5 inches or so). At that small size if they are released at a time of low food abundance they are more likely to die than "stunt"

Curt