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Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 1
photo courtesy of The Chronicle, Centralia, Washington
Chehalis Basin StrategyExtensive Off-channel
Habitat Surveys
Presented by
Marc Hayes, Julie Tyson, and Keith Douville
September 22, 2015
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 2
0
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100
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Numberof
Off-channelHabitats
Proportionof
Off-channelHabitatssampledthrough
June 2015
ExtensiveOff-Channel
SurveysSite Sampling
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 3
• Multiple methods‒ Three types of trapping (collapsible minnow, fyke nets, and
turtle traps)‒ Dip-net sampling‒ Electrofishing
• Crews of three to five surveyors• Walking and kayak access• One overnight trap set on consecutive sampling days• Similarities to egg mass surveys
‒ All species and life stages judged different photographed‒ Georeferenced by individual off-channel unit
Sampling Methods
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 4
Target Non-Salmonid SpeciesSpecies
Detected?Egg Mass Surveys
ExtensiveSurveys
1 Beaver (Castor canadensis) Yes Yes
2 Northern Red-legged Frog (Rana aurora) Yes Yes
3 Olympic Mudminnow (Novumbra hubbsi) Yes Yes
4 Oregon Spotted Frog (Rana pretiosa) No No
5 Western Pond Turtle (Actinemys marmorata) No No
6 Western Toad (Anaxyrus boreas) No Yes*
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 5
0%
20%
40%
60%
80%
100%
0
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4
6
Numberof
Off-channelHabitatswhere
Detected
Percentageof
Off-channelHabitatsSampled
whereDetected
Extensive Surveys:Northern
Red-legged Frog
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 6
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20%
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60%
80%
100%
0
1
2
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4
Numberof
Off-channelHabitatswhere
Detected
Percentageof
Off-channelHabitatsSampled
whereDetected
OlympicMudminnow
2 2 2 22
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 7
Another Target Species Detected• Two juvenile toads next
to one off-channel unit next to the Satsop River entry to Chehalis floodplain
• Toads breed in Satsop at low flow
• Thus, these juvenile toads may not be from off-floodplain off-channel habitat
Western Toad
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 8
Non-Target Amphibians Recorded
SpeciesNumber of Sites (%)
Egg Mass Extensive
1 American Bullfrog (Lithobates catesbeianus) 34 (66) 18 (63)
2 Long-toed Salamander (Ambystoma macrodactylum) 25 (49) 1 (3)
3 Northwestern Salamander (Ambystoma gracile) 42 (88) 16 (65)
4 Pacific Treefrog (Pseudacris regilla) 42 (81) 10 (44)
5 Roughskin Newt (Taricha granulosa) 17 (36) 15 (55)
• Same amphibian species as in egg mass surveys• Amphibians exiting aquatic habitat less detected• Newts more frequently detected• Bullfrogs similarly widespread
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 9
0%
20%
40%
60%
80%
100%
0
1
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Numberof
Off-channelHabitatswhere
Detected
Percentageof
Off-channelHabitatsSampled
whereDetected
AmericanBullfrog
22 2
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 10
Fishes RecordedSpecies
Percentage of Sites (%)Egg Mass Extensive
1 Black Crappie (Pomoxis nigromaculatus) 0 152 Bluegill (Lepomis macrochirus) 3 333 Bullhead catfishes (Ameiurus spp.) 1 314 Chinook Salmon (Oncorhynchus tshawytschaw) 2 05 Coho Salmon (Oncorhynchus kisutch) 8 06 Goldfish (Carassius auratus) 3 07 Lamprey (Entospenus or Lampetra sp.) 3 58 Largemouth Bass (Micropterus salmoides) 1 209 Largescale Sucker (Catostomus macrocheilus) 3 5
10 Northern Pikeminnow (Ptychocheilus oregonensis) 15 23
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 11
Fishes Recorded (cont.)Species
Number of Sites (%)Egg Mass Extensive
11 Olympic mudminnow (Novumbra hubbsi) 42 3312 Pumpkinseed (Lepomis gibbosus) 1 1913 Redside Shiner (Richardsonianus balteatus) 3 514 Rock Bass (Ambloplites rupestris) 1 1715 Sculpins (Cottus sp.) 15 4916 Speckled Dace (Rhinichthys osculus) 2 217 Three-spined Stickleback (Gasterosteus aculeatus) 8 6318 Yellow Perch (Perca flavescens) 3 719 Unidentified Juvenile Sunfishes (Lepomis sp.) 1 23
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 12
• At least 18 fish species (combined surveys)• Differences in extensive vs. egg mass surveys
‒ No salmonids or goldfish recorded
• Centrarchid fishes (basses, crappies, and sunfishes) and bullhead catfishes ~4-10 times better detected
• Sculpins and sticklebacks ~3-8 times better detected• All rest of natives detected roughly at the same level• Like bullfrogs, exotic fish predators (basses, crappies,
sunfishes, and catfishes) widespread except at tails of floodplain
Fish Patterns
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 13
0
20
40
60
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BullfrogsCentrarchid Fishes
Percentageof
SitesWhereExotic
PredatorCategoryDetected
ExoticPredator
Distribution
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 14
• Extensive and egg mass surveys complimentary
• Egg mass more amphibian effective; extensive more fish effective
• Yet, both gave similar patterns
• Except for one species (western toad), both surveys detected three of six possible target species (includes beaver; discussed later)
• Western toad seems rare in floodplain habitats
• Exotic predators seem widespread except at floodplain ends
• Patterns may suggest a least-risk route for restoration - focus on exotic predator-rich habitats with hydrological manipulation that may reduce exotic predator load
Summary
Extensive Off-channel SurveysPresented by Marc Hayes, Julie Tyson, and Keith Douville 15
Questions/Discussion