Transcript ALFISH - ATLSS Landscape Fish Model

ALFISH
Objectives
•Provide estimates of effects of alternative
water management scenarios on spatial and
temporal distribution of food resources for
upper trophic level consumers (wading
birds).
Approach
ATLSS Landscape Fish Model
Holly Gaff, Rene’ Salinas, Louis Gross, Don
DeAngelis, Joel Trexler, Bill Loftus and John
Chick
A size-structured population model for fish
functional groups (large and small fish) that
operates on a spatial cell basis with movement
between cells and between habitats within
•Provide method to evaluate hypothesized
impact of hydrologic changes on fish
community composition.
cells.
ALFISH FLOW CHART
Fish Cell Layout
Example of Small Fish
Least Killifish
Heterandria formosa
Female
Male
Pond areas assumed permanently
wet, marsh areas periodically dry
Landscape Layout and Movement
Fish as Prey
Fish provide the prey-base for
endangered wading bird species such
as Great Egret (Casmerodius albus)
White - movement from low water to high water areas
Red - movement from high fish density to low density
areas
ALFISH MODEL EXAMPLE RESULTS - Alt D13r4 compared to F2050Base
Fish Available as Prey during
a Typical Rainfall Year
Fish Available as Prey during
a High Rainfall Year
Average Fish Available as
Prey from 1965 - 1995
Fish Available as Prey during
a Low Rainfall Year
Distribution of Sizes for Fish
in WCA 3A
Total Fish Densities through
31-year Model Run
Average Fish Available as
Prey during Breeding Season
for Wading Birds
Total Fish Densities for
Certain Years in Given Areas