john day river major tributary to mid-columbia river no large dams (but downstream in columbia)
DESCRIPTION
A life history framework to understand production of juvenile steelhead in freshwater applied to the John Day River, Oregon Jason Dunham , USGS Forest and Rangeland Ecosystem Science Center John McMillan , Department of Fisheries and Wildlife, OSU - MS - PowerPoint PPT PresentationTRANSCRIPT
A life history framework to understand production of juvenile steelhead in freshwater applied to the John Day River, OregonJason Dunham, USGS Forest and Rangeland Ecosystem Science Center
John McMillan, Department of Fisheries and Wildlife, OSU - MSJustin Mills, Department of Fisheries and Wildlife, OSU - MSMatt Sloat, Department of Fisheries and Wildlife, OSU – Ph.D. (new)
Gordie Reeves, US Forest Service Pacific Northwest Research Station
Chris Jordan, National Marine Fisheries Service, Northwest Fisheries Science Center
John Day River
•Major tributary to mid-Columbia River
•No large dams (but downstream in Columbia)
•No hatcheries (but hatchery “strays” present)
•Mix of listed “steelhead” and non-listed “rainbow trout” present
•Broad-scale environmental variability
Major reasons for listing steelhead as a threatened species in the Mid-Columbia
• Declines in abundance of wild populations• Present abundance <<< historical• Hatchery influences + uncertainty• Habitat alteration• Lack of information regarding interactions
between resident rainbow trout and anadromous steelhead
• Busby et al. 1996; NMFS 1999
Three Questions
• Why “steelhead” and “rainbow” trout?
• How do we tell them apart?
• What do we do about it?
Why “steelhead” and “rainbow” trout?
• Variation in migration behavior– Growth and survival tradeoffs– How to make it to maturity?
Jonsson and Jonsson 1993; Hendry et al. 2004
Why “steelhead” and “rainbow” trout?
• Variation in migration behavior– Growth and survival tradeoffs– How to make it to maturity?
• Influence of sex– Once mature how to maximize fitness?– Different sexes = different problems
• Males – mate with females• Females – fecundity
Jonsson and Jonsson 1993; Hendry et al. 2004
Sex and mating tactics (e.g., Gross 1991)
Onchorhynchus mykiss
Males Females
Freshwater“Precocial” or resident
Marine (<2 years)“Jacks”
Marine (>2 years)“Hooknose” males
Freshwater
AnadromousSneaking
Sneaking, mimicry?
Fighting
Mating tactic Habitat use Habitat use
Common mating patterns
Onchorhynchus mykiss
Males Females
Freshwater“Precocial” or resident
Marine (<2 years)“Jacks”
Marine (>2 years)“Hooknose” males
Freshwater
AnadromousSneaking
Sneaking, mimicry?
Fighting
Mating tactic Habitat use Habitat use
Why do we care about “rainbows?”Long-term viability and life history diversity
• Interbreeding of “steelhead” and “rainbows”– Increased Ne of O. mykiss
Why do we care about “rainbows?”Long-term viability and life history diversity
• Interbreeding of “steelhead” and “rainbows”– Increased Ne of O. mykiss
• Flexible expression of life history possible– Spreading risk across habitats– Buffer periods of low survival in FW or marine
How do we tell them apart?
1. Use of neutral genetic markers
• Genetic differences among different life histories within the same basin are generally less than differences among basins (McPhee et al. 2007).
How do we tell them apart?
1. Use of neutral genetic markers
• Genetic differences among different life histories within the same basin are generally less than differences among basins (McPhee et al. 2007).
• Difficult to isolate “life history” from other confounded factors that lead to genetic isolation
– Isolation by distance or habitat type– Isolation by timing of reproduction– Episodic gene flow
How do we tell them apart?
1. Use of neutral genetic markers
• Genetic differences among different life histories within the same basin are generally less than differences among basins (McPhee et al. 2007).
• Difficult to isolate “life history” from other confounded factors that lead to genetic isolation
– Isolation by distance or habitat type– Isolation by timing of reproduction– Episodic gene flow
• Difficult to ID what a “rainbow trout” or “steelhead” is in your sample (esp. males)
2. Direct observation
• Mating behavior in the field– Spatial and temporal isolation
» Zimmerman and Reeves, McMillan 2007
How do we tell them apart?
2. Direct observation
• Mating behavior in the field– Spatial and temporal isolation
» Zimmerman and Reeves, McMillan 2007
• Otolith microchemistry– Sr/Ca ratios (higher in seawater)
» Zimmerman et al.
How do we tell them apart?
2. Direct observation
• Mating behavior in the field– Spatial and temporal isolation
» Zimmerman and Reeves, McMillan 2007
• Otolith microchemistry– Sr/Ca ratios (higher in seawater)
» Zimmerman et al.
• Examination of maturity– Mature female in freshwater ≠ steelhead– Mature male in freshwater…?
How do we tell them apart?
Two studies in the John Day River
• Spatial distribution of anadromous females(Justin Mills, MS)
– Indirectly inferred from juveniles (0+, 1+)– Chemistry of otolith primordium
• Spatial distribution of mature individuals(John McMillan, MS)
– Males– Females
Two studies in the John Day River
• Spatial distribution of anadromous females(Justin Mills, MS)
– Samples @ ODFW EMAP sites– Spatial patterns– Landscape influences
• Water temperature• Water chemistry• Network position• Channel morphology• Flow regime/discharge• Barriers
Two studies in the John Day River
• Spatial distribution of mature individuals(John McMillan, MS)
– Maturation of age 1+ males• Individual condition
– Body size– Prior year growth– Lipid %
– Individual condition• Water temperature• Population density of O. mykiss• Alkalinity/conductivity
What do we do about it?
• Life history expression– A “filter” for production of anadromous O. mykiss
• Filter can be applied in two ways:– Manage by location (=static processes)– Manage processes that influence life history
expression (=dynamic processes)
NaturalProcesses
Human Influences
Bio-physicalEnvironment
AbundanceProductivity
Processes influencing life histories
Steelhead juvenile production
NaturalProcesses
Human Influences
Bio-physicalEnvironment
AbundanceProductivity
Locations withdifferent proportions
of anadromy
Steelhead juvenile production
Freshwater resident
production
Assumptions
• Location: Panad = Constant (static processes)– Genetic (e.g., high heritability of anadromy)– Related to “immutable” environmental
influences– Management constrained to locations with
potential
Assumptions
• Location: Panad = Constant (static processes)– Genetic (e.g., high heritability of anadromy)– Related to “immutable” environmental influences– Management constrained to locations with potential
• Process: Panad = Variable processes– Flexible expression – phenotypic plasticity
• Variability in males > females
– Related to variable environmental influences– Some of above can be influenced by management
Examples
• Location– Intrinsic potential (Burnett et al. 2007)– Influence of groundwater (Zimmerman and
Reeves)
Examples
• Location– Intrinsic potential (Burnett et al. 2007)– Influence of groundwater (Zimmerman and
Reeves)
• Process– Barriers: anadromous resident– Emergence of anadromy from residents– Short term changes in life history related to
changes in temperature (Dunham et al. unpubl)
Immature Mature male Mature female
0%
20%
40%
60%
80%
100%
Age 0+
Occurrence
UB
30
BR
36
BD
72
Age 1+
UB
106
BR
53
BD
57
Age 2+
UB
19
BR
8
BD
8
Cool Warm
Modeling approach
• Deal explicitly with life history expression in O. mykiss
• Be spatially explicit
• Provide multi-scale context (site versus stream network)
• Integrate physical and biological processes
NaturalProcesses
Human Influences
Bio-physicalEnvironment
AbundanceProductivity
Processes influencing life histories
Steelhead juvenile production
Freshwater resident
production
NaturalProcesses
Human Influences
Bio-physicalEnvironment
AbundanceProductivity
Locations withdifferent proportions
of anadromy
Steelhead juvenile production
Freshwater resident
production
Modeling approach
• Deal explicitly with life history expression in O. mykiss• Be spatially explicit• Provide multi-scale context (site versus stream network)• Integrate physical and biological processes
• Inform on-the-ground decisions
• Relate to specific management actions
• Be easily manipulated to evaluate alternative scenarios
NaturalProcesses
Human Influences
Bio-physicalEnvironment
AbundanceProductivity
Processes influencing life histories
Steelhead juvenile production
Freshwater resident
production
NaturalProcesses
Human Influences
Bio-physicalEnvironment
AbundanceProductivity
Locations withdifferent proportions
of anadromy
Steelhead juvenile production
Freshwater resident
production
Modeling approach
• Inform on-the-ground decisions • Relate to specific management actions• Be easily manipulated to evaluate alternative scenarios
• Be flexible in using different sources of information
• Deal explicitly with uncertainty• Easy to understand with transparent
assumptions
NaturalProcesses
Human Influences
Bio-physicalEnvironment
AbundanceProductivity
Processes influencing life histories
Steelhead juvenile production
Freshwater resident
production
NaturalProcesses
Human Influences
Bio-physicalEnvironment
AbundanceProductivity
Locations withdifferent proportions
of anadromy
Steelhead juvenile production
Freshwater resident
production
Expected outcomes
• A better understanding of complex relationships influencing production of juvenile steelhead in freshwater.
• Identify major uncertainties.• Testable hypotheses about management
alternatives monitoring and evaluation.• A straightforward management framework
and tool that can be applied to inland steelhead in general.
Timelines
• Model of anadromy – 2008/09
• Freshwater maturation - 2008/09
• Model of freshwater productivity – 2011
• Ph.D. dissertation - 2012
North Fork John Day River 2006: John McMillan photo
Questions - Discussion
RESIDENTFISH
MIG
RA
TIO
N
RESIDENTFISH
DISPERSAL
HO
MIN
G
HO
MIN
G
Migration behavior: habitat use, dispersal, “straying”
“STRAY”“STRAY”