Kuskokwim-Wide Invasive Species Concerns

Invasive species are a concern throughout Alaska – whether they be the terrestrial kind like troublesome orange hawkweed or other rapidly spreading invasive plants, tunicates found in salt water near Sitka or the freshwater waterweed (i.e., Elodea) rapidly expanding in the Chena Slough area near Fairbanks.

For that reason the Native Village of Napaimute and the Kuskokwim River Water Council have come up with a poster that will be posted locally in the villages and regional float plane lakes; it will also be sent to all the guides and outfitters that bring out-of-state clients to the Kuskokwim tributaries who have the potential for bringing an unwanted invasive to the region.

Here is a letter sent to the outfitters and guides:

Hello ,

My name is Dave Cannon and I’m the Environmental Director for the Native Village of Napaimute located on the Kuskokwim River about 30 miles upriver of Aniak.

Several years ago I was the Invasive Plant Coordinator for the middle Yukon-Kuskokwim Region but prior to that I was mostly involved with fish issues since I’m a fish biologist.  I learned that not too long ago most Alaskan botanists didn’t think invasive plants were a big concern due to our remoteness and severe climate.  Unfortunately, they know differently now.  My exposure to the world of invasive plants really opened my eyes as to just how problematic invasives can be – even here in the more the more remote parts of the state.  Of particular concern is reed canarygrass that has the potential to reduce salmon spawning habitat.

Having worked in the lower 48, I was familiar with whirling disease that was prevalent in Colorado, Montana and other Western states as well as the typical hatchery related diseases (e.g., BKD or bacterial kidney disease) since I worked at the Jackson National Fish Hatchery in Jackson Hole, Wyoming prior to being the fish biologist for the Yukon Delta National Wildlife Refuge in Bethel.

There are numerous ongoing efforts to minimize the threats.  While in Bethel I participated in a National Wild Fish Health Survey conducted by the U.S. Fish and Wildlife Service where we collected baseline tissue samples on rainbow trout in the Kisaralik River; this study was partly driven by the concern over whirling disease.  Fortunately, no diseases were found at that time.

I probably don’t have to dwell then on what the concerns are, but in one Montana study 40% of the anglers did not clean their equipment between uses (Gates et al. 2006).  In another study on aquatic invasive species transport via trailered boats,the authors found that although fishing guides moved among waterways with a greater frequency than anyone else, they often employed less-than-ideal boat cleaning practices…mostly due to inconvenience.

It is our hope that everyone involved will take the extra time to reduce the threat of introducing unwanted organisms to the Kuskokwim drainage so that we never have to deal with such things as whirling disease, rock snot or Elodea (a type of a water weed).  I’ve attached a poster in pdf format expressing our concern and suggestions for ways to minimize the potential for unwanted introductions.

Here are some simple guidelines to follow above and beyond what’s on the poster: 


 CLEAN – Rinse and remove all visible mud, plants, fish/animals from boats, trailers, float plane rudders and floats, and gear

 DRAIN – Drain water from coolers, floats, bilge pumps, buckets, and wring out gear before leaving the boat launch or fishing area 

DRY – Completely dry equipment and gear between visits to different waterbodies

 *Never release plants, water, fish, or animals into a body of water*

Please feel free to E-mail or call me if you have any questions.  If you would like a printed version of the poster to display in a prominent location please contact me and we’ll send one out.  Thank you in advance for your cooperation.


Dave Cannon

Environmental Director

Native Village of Napaimute for the Kuskokwim Watershed Council

P.O. Box 355, Aniak, AK 99557

(907) 675-4443 © 676-0012


Gates, K. K., K. Meehan, and C. S. Guy. 2006. Angler movement patterns and the spread of whirling disease in the greater Yellowstone ecosystem. Association of Pacific Coast Geographers, Sacramento, California. Available: www.wou.edu/pacifica. (February 2007).

Rothlisberger, J.D., W.L. Chadderton, J. McNulty, and D.M. Lodge. 2010.  Aquatic invasive species transport via trailered boats: What is being moved, who is moving it, and what can be done.  Fisheries 35 (3): 121-132.

Page 1 Help Keep Aquatic Invasives Out Of The Kuskokwim

Page 2 of the poster

May 30 – First Kuskokwim Salmon Management Working Group Meeting

The Department of Fish & Game discussed some changes going into this season as far as projects they have going and their plans on managing the salmon going into this upcoming season.

A surprise to me, and to many, is that the Department will no longer operate the Aniak sonar project which is, or has been, the 2nd longest running project in the drainage; the Kogrukluk weir on the upper Holitna has been around since 1976.  The Aniak sonar was put in in 1980.

The reason it won’t be operated anymore is two-fold.  First, money for projects is getting tight, and this project never provided hard numbers.  Since it couldn’t differentiate between species very well, it only gave what is considered an index.  The Department tried to speciate by drifting a gill net in the area, but that couldn’t effectively work the deeper water.  So it was generally assumed the chums comprised the bulk of the run in the Aniak…and no doubt that is true – especially when in some years over 1 million return.

With time technology has improved, and newer equipment was able to differentiate between salmon sized fishes and very small fish, but still precision was lacking.

Keep that in mind when you think about managing the Yukon River salmon runs and the Pilot Station sonar.  I’m not saying that that system shouldn’t be used, because at times a manager has to use the best tool that is available, even if it’s not totally reliable.  At least on the Yukon they have other tools further upriver that they can judge the results of the sonar against.

The Department decided that their money would be well spent if they put a weir upstream on the Salmon River where they could get hard numbers for all salmon species.  There was a weir there beginning in 2006 that ran for about four years; one ADF&G biologist and myself operated it the first year it was in place.

Management Scenarios

The State has a projection of about 197,000 Chinook that they anticipate will return to the drainage this year.  They have been working on what’s called a run reconstruction for Chinook salmon with all the previous years’ data from all the projects.  It’s their best guess as to what the runs were like years ago and what we’ve got now.  In some years it’s estimated that as high as 300,000 or more Chinook have come back.

The Department considers the subsistence harvest to be about 70,000 a year.  As a part of the run reconstruction, they also attempt to come up with a drainage-wide escapement number that they believe would provide for sustainable returns.

They then work with those two numbers (subsistence needs + escapement needs) and determine whether or not there is a harvestable surplus for commercial fishing.

Here’s where things get – or got – interesting yesterday.

There is a pretty good disagreement as to what the Fish & Wildlife Service thinks should be coming back as far as total escapement throughout the drainage.  The State figured around 87,000 but the FWS is inclined to think that that number should be around 133,000…quite a difference.

This difference of opinion goes back many years, in fact ten or more from back when I was the biologist for the Yukon Delta National Wildlife Refuge.

The State uses a computer model to look at past returns, and then the returns years later from those returns; it’s called a spawner-recruit model.  In places like Bristol Bay where they’ve been collecting data for 80 or more years, that can work pretty well.  But in places like the Kuskokwim where we have very limited data, it may not be any better than the sonar up the Aniak!

The Department pretty much goes with that model’s results, where the Fish & Wildlife Service believes that other ecological considerations should be considered.   The problem is trying to incorporate those things into a model…definitely not easy.  The FWS believes that the flesh, eggs, etc. that are eaten by so many animals (including young salmon) need to be considered into the mix, as well as the importance of the marine derived nutrients that salmon bring back with them.  Therefore, the FWS has always promoted more salmon returning.

When you look at the weir project numbers that are on the included Chinook Salmon Conservation poster, you can see that the past few years the escapement numbers for the Tuluksak and Kwethluk rivers is way down.  This is another reason the FWS would like to see higher escapement numbers to help build those populations back up.

How does that difference of opinion fit into this coming season’s management?  Lets go back to the projection that ADF&G believes will come back this year – 197,000.  If the subsistence needs are 70,000 and the escapement necessary (ADF&G’s number) is 87,000 – then there would be a harvestable surplus that could potentially be fished on; not that the Department would take the remaining 40,000 (197,000 – ((70,000+87,000)).  But they are hoping to fish on the chums knowing that there would be an incidental harvest of probably less than 1,000 Chinook.  Keep in mind that the decision makers are from the Commercial Fisheries Division – it’s their job to provide a fishery when fish are available.

BUT – if the Fish and Wildlife Service believes that 133,000 need to come back just for escapement alone, then that changes the harvestable surplus…or eliminates it in this case (70,000 + 133,000 is more than the expected 197,000).  So that now changes the Department’s management options.

In this scenario there couldn’t be a chum fishery until after all the kings went by…which is too late for the processor.  The processor needs to plan ahead knowing that he has some sort of a guarantee.

In deliberations earlier this week with the FWS the Department compromised in a sense and are considering 120,000 necessary for escapement; but depending on how accurate their projection is that doesn’t leave much room for a harvestable surplus if little more than 197,000 returned.  If less than that come back escapement won’t be met.

Keep in mind that all this is based off the one in-season tool that’s available – the Bethel Test Fishery.

And this got the Working Group concerned.  Lets go back to the State’s original escapement number of 87,000.  If 197,000 Chinook did show up – or was a little lower than that – the State wouldn’t anticipate any subsistence restrictions…at least not right off the bat.

As the run progressed and it turned out to be very weak, then rolling closures would likely be implemented with them starting at the mouth and working upstream.  If things were really bad, we in Napaimute would see a 7-day period closed at sometime; we would have at least a week or more notice as to when that would happen.  The closer to Kuskokwim Bay the shorter the notice would be.

But if the State conceded and went with the 133,000 escapement and the Bethel Test Fishery shows very few fish, then subsistence restrictions in the form of that rolling closure would kick in almost immediately for the downstream-most villages.

That would set off a panic situation much like last year…and no one wants that.  The Working Group and ADF&G will be trying to get the message out over various media outlets that there is a likelihood that sacrifices may be necessary this year in hopes that if closures are warranted, that people won’t be blind sided.

So at this time the State and feds haven’t come to consensus.  They will, however, be deliberating all this next week and try to find common ground by next Wednesday’s meeting that will disrupt as few people as possible.  Either way, be prepared for a weaker than normal run.

May 12 – Saturday Update – My Last From Napaimute Till Next Year

Woke up to some fresh snow and very little ice passing by – more wood than ice.  The water level hasn’t changed much in the past few days.

Eric Morgan Jr. will come up tonight by boat and take me back to Aniak where I’ll have to stay until I can cross the slough, hopefully in a day or two, until I can get across to my apartment.

Looking upstream at a peaceful and serene Kuskokwim

Looking downstream over the basketball court dusted with fresh snow

May 10 Update 8:00 AM

Relatively little ice and wood, although there is still a decent amount of wood passing by for you downriver folks.  Even though we had a little rain last night the water level has changed minimally.


Ducks and geese are heading west and several peregrine falcons are nesting up behind the Chapel.

Downstream View

Upstream view