Missing collaborator

Conceptual Overview

SHIRAZ

LandscapeProcesses

Land Use

FreshwaterHabitat

BiologicalResponse

Land use & landscape processes affect habitat

Freshwater habitat affects productivity & capacity

The SHIRAZ model

• Developed for Muckelshoot Tribe in WA to evaluate ESA recovery planning for salmon

• Uses flexible life history, with reach by reach specification of habitat characteristics

• Basic structure can be simplified and adapted to meet various needs (i.e. it’s a framework)

• Built with Visual Basic & integrates with Excel

Alternative life histories

• Spawners• Adults

• Spawners• Eggs• Fry• First winter residents• Smolts• Ocean residents• Adults

Relate life history to habitat

Stage 1

Stage 2

Stage 3

Habitat

Habitat

s

ss

N

NN

cp111

Multistage Beverton-Holt Model(Mousalli & Hilborn 1986)

Ns ≡ individuals alive at stage s

p ≡ max. survival rate from s s+1 ≡ “productivity”

c ≡ max. N producible at s+1 ≡ “capacity”

Key AttributesIn general• Freshwater survival driven by relationships between habitat, p, & c

• c determined by quantity of habitat• p determined by quality of habitat

Also assume• Freshwater survival is density-dependent• Marine survival is density-independent

Habitat Variables

• Inherent “hard-wired”1) spawning area

2) rearing area

3) % fines

4) % impervious

• Generic– Increase or decrease c & p around a “reference” level

– Multiplier specified by a general quadratic relationship

– Based on difference between present state and reference

Multiplier = exp[f1(state – ref) + f2(state – ref)2]

Example of Habitat Relationship

R2 = 0.95

0

20

40

60

80

100

0 20 40 60 80

Fine sediment (%)

Egg

to fr

y su

rviv

al (

%)

Changing habitat variables

Hmax

0

trend<0

trend>0

2) Intervention (i.e. bulk addition or removal)

1) Underlying trend (i.e. annual increase or decrease)

Hmax

0Time

(+)

(-)

Other model featuresHarvest strategies

Ocean survival

Hatchery influence

Integration with PRISM

SHIRAZ

LandscapeProcesses

Land Use

FreshwaterHabitat

BiologicalResponse

PRISM

Linking landscape to life history

Stage 1

Stage 2

Stage 3

FW Habitat

Ocean HabitatHydrology

Landscape Processes

Land use

Climate

Current status

• Programming interactive improvements

• Researching habitat-fish relationships

• Researching hydrology-habitat relationships

Moving Forward

• Choose watershed (Snohomish or Puyallip/White?)

• Add variable hydrology inputs

• Allow for various “what if” scenarios

Example scenario

Precipitation

Str

eam

flo

w

% fines

Fry

sur

viva

l

Stream flow

% f

ines

Ambient

Decrease

Increase?

Ocean regime shifts

• Evaluation of alternative harvest strategies should be robust to uncertainty about future ocean changes

• May want to include known ocean changes based on historical data

SHIRAZSummary

• It’s a modeling framework• Uses flexible life history• Spatially explicit habitat characteristics• Basic structure can be simplified and adapted