Commercial Gill Nets Target BASS in Lake WA

[Kola16]

https://link.springer.com/article/10.1007/s10641-020-01016-0
Columbia smallmouth and chinook...

"We estimated that 869,371 subyearlings could be lost to smallmouth bass predation between riverine production areas and Lower Granite Dam in a given year. To provide a context for this estimated loss, we provide an illustration of its potential effect on the adult population. Assuming no juvenile mortality occurred downstream of the dam and depending on smolt-to-adult return rates, this represented up to 3.9–16.0% of the potential adult run that could have returned to Lower Granite Dam had no subyearling predation by smallmouth bass occurred upstream of the dam. Although this study was limited by a number of assumptions and constraints, it does provide an illustration of how predation affects juvenile and adult salmon loss over a broad, changing river landscape."

[Kola16]

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.578.8595&rep=rep1&type=pdf
Washington lakes and coho...

Over two years, we examined predation impacts of ten common introduced fishes (brown bullhead catfish Ameiurus
nebulosus, black crappie Pomoxis nigromaculatus, bluegill Lepomis macrochirus, golden shiner
Notemigonus crysoleucas, green sunfish Lepomis cyanellus, largemouth bass Micropterus
salmoides, pumpkinseed Lepomis gibbosus, rainbow trout Oncorhynchus mykiss, warmouth
Lepomis gulosus, and yellow perch Perca flavescens) and two native fishes (cutthroat trout
Oncorhynchus clarki, and prickly sculpin Cottus asper) on wild juvenile coho salmon
Oncorhynchus kisutch in three shallow western Washington lakes, all located in different
watersheds. Of these species, largemouth bass were responsible for an average of 98% of the
predation on coho salmon in all lakes, but total impact to each run varied among lakes and years.
Very few coho salmon were eaten by black crappie, brown bullhead catfish, cutthroat trout,
prickly sculpin, and yellow perch, while other species were not observed to eat coho salmon.
Juvenile coho salmon growth in all lakes was higher than in nearby streams. Therefore, food
competition between coho salmon and introduced fishes in lakes was probably not limiting coho
salmon populations. Largemouth bass are widespread, present in 85% of lowland warmwater
public-access lakes of Washington (n=421). Future research would help identify impact of
largemouth bass predation across the region, and prioritize lakes where impacts are most severe.
Nevertheless, attempts to transplant or increase largemouth bass numbers in lakes important to
coho salmon would be counterproductive to coho salmon enhancement efforts.

[Kola16]

https://depts.washington.edu/oldenlab/wordpress/wp-content/uploads/2013/03/FreshwaterBiology_2012a.pdf
To sum it up...Chinook are sitting ducks to smallmouth...

1. Non-native predators might inflict proportionally higher mortality on prey that have no
previous experience of them, compared to species that have coexisted with the predator for some
time.
2. We tested whether juvenile Chinook salmon (Oncorhynchus tshawytscha) were less able to
recognise a non-native than a native predator, by investigating behavioural responses to the
chemical cues of the invasive smallmouth bass (Micropterus dolomieu) and the native northern
pikeminnow (Ptychocheilus oregonensis) in both laboratory and field experiments.
3. Laboratory results demonstrated strong innate antipredator responses of individual juvenile
Chinook salmon to northern pikeminnow; fish spent 70% of time motionless and exhibited 100%
greater panic response than in controls. By contrast, antipredator responses to the chemical cues of
smallmouth bass did not differ from controls.
4. These results were supported by similar differences in recognition of these predator odours by
groups of juvenile Chinook salmon in fully natural conditions, though responses reflected a
greater range of antipredator behaviours by individuals. In field trials, responses to northern
pikeminnow odour resulted in increased flight or absence, reductions in swimming and foraging,
and increased time spent near the substratum, compared to smallmouth bass odour.
5. Given that survival of juvenile fish is facilitated by predator recognition, our results support
the hypothesis that naivety may be an important factor determining the effect of non-native
predators on prey populations. Efforts to manage the effect of native and non-native predators
may benefit by considering complex behavioural interactions, such as these at the individual
and group levels.

[Kola16]

https://www.fws.gov/wafwo/pdf/CedarR-predation-USFWS-final-report-Feb2014.pdf

Smallmouth Bass in the Pacific Northwest: A Threat to Native Species; a Benefit for Anglers

[Kola16]

https://www.fws.gov/wafwo/fisheries/Publications/Pred_tracking_LWSC_final_report_Sept2010.pdf
Bass in Lake WA...

"Smallmouth bass inhabited a wide range of depths between 0 and 10 m deep but were
mostly found in the 2-4 m depth interval. The large area of the Gas Works Park site that was >
12 m deep was rarely used. Smallmouth bass strongly selected the bridge support structures at
the I-5/University Bridge site but also showed some positive selection for sparse vegetation,
vegetation edge, and nearshore overwater structures. At the Gas Works Park site, they showed a
selection for the beach shoreline and gravel/sand substrate. Smallmouth bass inhabited deeper
areas at the I-5/University Bridge site than at Gas Works Park; this was due largely to the use of
the deep support structures of the University Bridge. Large offshore, deep structures like the
University Bridge appear to allow smallmouth bass to inhabit offshore, deeper waters and
probably have greater overlap with juvenile Chinook salmon.

Course-scale tracking of smallmouth bass showed they have a strong seasonal migration
pattern between the LWSC and Lake Washington. Of the smallmouth bass we were able to
obtain seasonal movement information, 82% migrated to Lake Washington sometime between
June and October. Smallmouth bass < 350 mm FL were more likely to overwinter in the LWSC
and if they did migrate to Lake Washington, they migrated later in August-October. Most
returning smallmouth bass appeared to move into LWSC sometime from early March to midApril. Timing of their return to the LWSC appears to correspond to the initial warming period in
the spring and may be directly related to spawning. Smallmouth bass often showed some degree
of site fidelity between years for both spring/summer locations in the LWSC and
summer/fall/winter locations in Lake Washington. Because smallmouth bass often have a high
degree of spawning site fidelity, there can be different populations within the same water body.
Smallmouth bass in the LWSC may represent one perhaps two separate populations from
smallmouth bass that inhabit Lake Washington year-round."

[Kola16]

There has been zero studies done on Lake Washington to prove this being a fact.

You positive about that

[BigGoonTuna]

i really have mixed feelings about this.  on one hand, our salmon populations are struggling and need a lot of help.  on the other hand, i'm not a big fan of wiping out a thriving fishery so that one that is functionally gone *might* benefit.

if we got rid of all non-native fish in this state, it sure would be some lousy fishing for the most part.  most lowland lakes don't even support natural populations of trout.  hope you like suckers and chub.

anadromous fish have incredibly complicated biology and it's a folly thinking that eliminating one threat to their existence like taking out predators, or dumping 10x more fish from a hatchery will restore their populations.  it's a death of 1000 cuts and a big part of that is that these fish don't really get along well with modern civilization.  they need cold, clean water (gone in the puget sound area), habitat (also gone), food (mostly gone) and predator control (good luck with our state government and the MMPA)

as sad as it is, i think that we are past the point of no return on a lot of salmonid stocks, and fishing for them as we knew it is pretty much gone.  how much opportunity have we lost in just the last 5 years?

[Stein]

https://depts.washington.edu/oldenlab/wordpress/wp-content/uploads/2013/03/FreshwaterBiology_2012a.pdf
To sum it up...Chinook are sitting ducks to smallmouth...

1. Non-native predators might inflict proportionally higher mortality on prey that have no
previous experience of them, compared to species that have coexisted with the predator for some
time.
2. We tested whether juvenile Chinook salmon (Oncorhynchus tshawytscha) were less able to
recognise a non-native than a native predator, by investigating behavioural responses to the
chemical cues of the invasive smallmouth bass (Micropterus dolomieu) and the native northern
pikeminnow (Ptychocheilus oregonensis) in both laboratory and field experiments.
3. Laboratory results demonstrated strong innate antipredator responses of individual juvenile
Chinook salmon to northern pikeminnow; fish spent 70% of time motionless and exhibited 100%
greater panic response than in controls. By contrast, antipredator responses to the chemical cues of
smallmouth bass did not differ from controls.

I must have a predator scent, sometimes when I go out fishing they just all freeze motionless and sit there and do nothing!

[Tbar]

i really have mixed feelings about this.  on one hand, our salmon populations are struggling and need a lot of help.  on the other hand, i'm not a big fan of wiping out a thriving fishery so that one that is functionally gone *might* benefit.

if we got rid of all non-native fish in this state, it sure would be some lousy fishing for the most part.  most lowland lakes don't even support natural populations of trout.  hope you like suckers and chub.

anadromous fish have incredibly complicated biology and it's a folly thinking that eliminating one threat to their existence like taking out predators, or dumping 10x more fish from a hatchery will restore their populations.  it's a death of 1000 cuts and a big part of that is that these fish don't really get along well with modern civilization.  they need cold, clean water (gone in the puget sound area), habitat (also gone), food (mostly gone) and predator control (good luck with our state government and the MMPA)

as sad as it is, i think that we are past the point of no return on a lot of salmonid stocks, and fishing for them as we knew it is pretty much gone.  how much opportunity have we lost in just the last 5 years?

Excellent post BigGoonTuna. Although I agree with most of your post I do not believe all is lost. The predation, on many levels, discounts the manipulations. Many cases I believe more salmon produced only facilitates a false carrying capacity for multiple predator species and may exacerbate the issue. The frustration is very real to multiple users.

[GWP]

Tribes (with the WDFW) have been searching for reasons why and how to help returning fish for some time. Just read an article that found possibly up to 50% of fish smolt are being eaten at the ship canal bridge floats where they bunch up. There is discussion on how to modify the floats or bridge structure to help.

[AKBowman]

For better or worse the Muckleshoot bios are back at it running 25 lines of nets 5 days a week on Lake WA.

Hit up some great spots yesterday for 5 hours. Perfect weather, perfect time of year. Caught 1 largemouth that was small enough to fit through their nets. Saw ZERO largemouth up shallow in spots where I normally catch at least 2-3 fish per spot.

Caught 2 smallmouth when I normally get 3-4 per hour on a day like yesterday early May.

Found nets strung from frost point through the west channel off Mercer. They had a couple points and bays COMPLETELY choke off and triangulated with nets.

Bio was there when I launched. Said they were now “studying” shad which are in the lake. He also said they were definitely targeting bass.

[huntnphool]

For better or worse the Muckleshoot bios are back at it running 25 lines of nets 5 days a week on Lake WA.

Hit up some great spots yesterday for 5 hours. Perfect weather, perfect time of year. Caught 1 largemouth that was small enough to fit through their nets. Saw ZERO largemouth up shallow in spots where I normally catch at least 2-3 fish per spot.

Caught 2 smallmouth when I normally get 3-4 per hour on a day like yesterday early May.

Found nets strung from frost point through the west channel off Mercer. They had a couple points and bays COMPLETELY choke off and triangulated with nets.

Bio was there when I launched. Said they were now “studying” shad which are in the lake. He also said they were definitely targeting bass.

 

[buckcanyonlodge]

Maybe it was said somewhere in the thread but I did not see it.....WHAT are they doing with all the fish they net...BASS, TROUT, PERCH,,,anything they kill in the nets. Does they tribe have a processing facility where tribal members fillet and package all the dead fish?? I'm sure there are lots of hungry tribal members that would love to have a freezer full of fish & chips meat...How about donating to any food bank in the area.
What a STINKING SHAME if they let them ROT. I have seen the results of in..an netting on the Columbia where there were PILES of ROTTING sturgeon at the boat ramp above John Day.
Maybe they could advertise  Free fish days at the boat launches where anyone could come and take the netted fish??
If I lived in the area I would volunteer to fillet fish at the boat ramps for hungry people. As a matter of fact I would volunteer to fillet the walleye,bass, burbot, whitefish, and trout they net out of Lake Roosevelt...Hit me up bio's...I'll even advertise the free fish days for you.
They are going to net the fish whether we like it or not,so please don't waste them.

[GWP]

I hope they are not wasting ANY fish from anywhere. Sturgeon left to rot would seem to be a criminal offense, would it not? Actually, any fish?
I am not familiar with the rules on Lake Wa Bass tourney's, but I have seen them out there. I would have to think if they did NOT return them to the water it would put at least a dent in the population?
The number of Walleye caught by WDFW during their yearly 'test runs' has increased every year as well. Only a matter of time before that becomes a problem.
Like the crab issue, you can NOT continue (of course you can!) to harvest to the max 'anything' and have it sustain.
While I believe the Tribe's and WDFW work together, and they have 'rights' to a certain amount of available fish, the 'Sovereign' part is a bit blurred these days, with the Fed Gov't giving them (our) money/grants and Tribe's getting exclusive and first pick of harvest of most critters of all types.
I believe the treaties should be held to, but should it be based on the number of people in the Tribe's that lived 'at the time', or the number of fish 'available at the time'? Not sure how the agreement was worded, and that would make a difference.
Probably a bigger issue is the commercial harvest and 'accidental' catch effecting all fish types.
The world has more mouths to feed, and a limited harvest available to do it with.

[buckcanyonlodge]

I hope they are not wasting ANY fish from anywhere. Sturgeon left to rot would seem to be a criminal offense, would it not? Actually, any fish?
I am not familiar with the rules on Lake Wa Bass tourney's, but I have seen them out there. I would have to think if they did NOT return them to the water it would put at least a dent in the population?
The number of Walleye caught by WDFW during their yearly 'test runs' has increased every year as well. Only a matter of time before that becomes a problem.
Like the crab issue, you can NOT continue (of course you can!) to harvest to the max 'anything' and have it sustain.
While I believe the Tribe's and WDFW work together, and they have 'rights' to a certain amount of available fish, the 'Sovereign' part is a bit blurred these days, with the Fed Gov't giving them (our) money/grants and Tribe's getting exclusive and first pick of harvest of most critters of all types.
I believe the treaties should be held to, but should it be based on the number of people in the Tribe's that lived 'at the time', or the number of fish 'available at the time'? Not sure how the agreement was worded, and that would make a difference.
Probably a bigger issue is the commercial harvest and 'accidental' catch effecting all fish types.
The world has more mouths to feed, and a limited harvest available to do it with.

It's not just the annual test netting. They are netting almost year round under the pretense of stopping the spread of northern pike. I watched one particular net pulled in and they had whitefish, burbot, trout, and walleye...NO northern pike. What is happening with those fish??