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Session Goals. The complexity of estimating population parameters Metrics for quantifying population status Linkage of these metrics to habitat features. Main Questions How do different habitats and their features affect salmon populations?
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Session Goals The complexity of estimating population parameters Metrics for quantifying population status Linkage of these metrics to habitat features Main Questions How do different habitats and their features affect salmon populations? What management options will best improve population persistence?
Eggs Adults Redd Stream Emergent Fry Spawning Adults Estuary Juveniles Adults Nearshore Juveniles Adults Ocean
Eggs LAND USE/ RESTORATION Incubation Conditions Freshwater Habitat Conditions Adults Estuary Habitat Conditions FISHING Redd Stream Emergent Fry Spawning Adults Estuary Juveniles Adults Nearshore Juveniles Adults Ocean
Nonlinearities? Interactions? Scale Dependency? Survival Low gradients Survival Pools Survival High gradients Reaches Woody Debris Stream Flow Tributaries Temperature The Complexity of Parameterizing a Habitat-Specific Model Habitat Variable Demographic variable Stream flow Temperature Gradient Substrate heterogeneity Riparian vegetation Woody debris Predator abundance Survival Fecundity Habitat Residency Age at maturity Sex ratio Density Capacity
Eggs Adults Redd Stream flow Temperature Gradient Substrate heterogeneity Riparian vegetation Woody debris Predator abundance Stream Emergent Fry Spawning Adults Estuary Juveniles Adults Nearshore Juveniles Adults Ocean
Redd m Eggs rj sa Stream Emergent Fry Spawning Adults sj ea Estuary Juveniles Adults Adults ej na Nearshore Juveniles Adults m nj Ocean o A Coarse-ScaleParameterization Skagit River
A Habitat-Specific Model for Pink Salmon Leslie Matrix r sen= habitat-specific survival µ = 1 - (harvest mortality) ox= ocean survival f = natal sex ratio m = age-specific fecundity
A Habitat-Specific Model for Pink Salmon * r sen= habitat-specific survival µ = 1 - (harvest mortality) ox= ocean survival f = natal sex ratio m = age-specific fecundity
A Habitat-Specific Model for Pink Salmon = * r sen= habitat-specific survival µ = 1 - (harvest mortality) ox= ocean survival f = natal sex ratio m = age-specific fecundity
Metrics of Population Status Number of juveniles: N(1)trsjejnj Number of spawners: N(2)to2a2µnaeasa Population productivity (l): Nt+1/Nt = *
A Habitat-Specific Model for Chinook Salmon r sen= habitat-specific survival µ = 1 - (harvest mortality) ox= yearly ocean survival f = natal sex ratio ax= age-specific breeding propensity mx = age-specific fecundity
Freshwater Survival y = 0.202 – 1.23*10-6x R2 = 0.87 From Seiler et al, 2000
A Habitat-Specific Model for Chinook Salmon r sen= habitat-specific survival µ = 1 - (harvest mortality) ox= yearly ocean survival f = natal sex ratio ax= age-specific breeding propensity mx = age-specific fecundity
Main Questions How do different habitats and their features affect salmon populations? What management options will best improve population persistence?
Eggs # o f Spawners Adults Present Future 20% Increase in Survival Redd What is the relative importance of each parameter? rj Stream Emergent Fry Spawning Adults sj Estuary Juveniles Adults ej Nearshore Juveniles Adults m nj Ocean o
rj sj ej nj ox m rj sj ej nj ox m How important is each parameter?
Density Dependence in Estuaries (Beamer et al 2000)
Density Dependence in Estuaries (Beamer pers. comm.)
Different Types of Density Dependence Have Different Consequences NDD Survival Habitat Selection
Research Priorities Effects of fine-scale habitat features Effects of large-scale variation on population dynamics Movements of salmon among aquatic habitats