Lab #9
Metapopulation Management Simulation
The following module is taken from the software package Ecobeaker, and describes conservation
efforts to save Fender’s Blue Butterfly and its host plant Kincaid’s Lupine in Oregon. The lupine has
largely disappeared owing to replacement of prairie by agriculture; the butterfly is threatened with
extinction as a result. Schultz’s (1998) paper on dispersal properties of the butterfly describes the butterfly
in further detail.
Follow the procedure described below, from an early  version the software package Ecobeaker,
trying three alternative management strategies: a) purchase one large reserve (let other populations go
extinct), b) connect one or more populations with corridors (each a continuous narrow band of prairie
habitat), and c) maintain the area as a series of unconnected islands, each of small size.
Begin by double-clicking on the Ecobeaker icon, and pull down under File to Open to load the
situation file “Butterflies”. The screen should now contain a “map” (8 km x 8 km) of western Oregon as it
would have appeared about 100 years ago, with the dominant prairie habitat shown in green. At the middle
right, a “Butterfly Population” window, and the small “Statistics” table below it, allow you to monitor
changes in the number of butterflies each week during any simulation runs. A control panel at the lower
left indicates the passage of time, and allows you to start, stop and reset a simulation.
To begin a simulation of butterfly dynamics predicted when the habitat was largely prairie a
century ago, click on the Go button in the Control Panel. The butterflies appear as blue dots in the map.
Note that the butterflies are univoltine, reproducing synchronously once per year. Record the approximate
mean and variation in butterfly numbers based on a simulation lasting several years based on the graph or
table. Click Stop when done.
Now pull down under Markers to Today, and note the replacement of most of the prairie with
farmland (shown in brown). Note (in the Statistics table) that 800 squares in the map consist of prairie.
Imagine that environmentalists in the city of Eugene have garnered enough funding to purchase 200
additional units of prairie; it is your task to provide guidance as to where those 200 units should be located.
Pull down under Actions to Paint. Then move your cursor to the “Habitats” window and click
once on Prairie to highlight it. Now add 200 additional units according to the first of your three alternative
plans above (creating one large reserve), either by clicking one square at a time or by click-and-dragging to
outline a block of squares. You can correct any mistakes by instead highlighting Farmland and returning
green squares to brown. You have to stop when the amount of prairie totals 1000 units, and cannot replace
existing prairie with farmland in order to create prairie elsewhere. Run a new simulation with the added
prairie configuration for approximately 50 years. Stop and Reset as necessary. Repeat the procedure one
or more times until you’re fairly certain you’ve optimized the location of your single reserve. Copy your
map and graph of the butterfly population dynamics over the interval to a Word file.
Now pull down under Markers to Today once more, and again add 200 more units to the original
800 units of prairie following a design that produces corridors between two or more existing prairie
fragments. Again run several simulations, and copy the map and graph of population dynamics to your
Word file.
Finally, create a series of stepping stones, and again save your best run to Word.
Write-up: Summarize the results of your simulations, and suggest an optimal strategy for long-term
persistence of the butterfly. The summary should include information derived from your reading of Schultz
(1998), on reserve in the library. Include the maps and graphs representing your three simulation results to
the paper, and suggest why the strategy you chose is more consistent with the biology of the butterfly than
the other two options. The paper will be graded on a 10 point scale.
Schultz, C.B. (1998). Dispersal behavior and its implications for reserve design in a rare Oregon butterfly.
Conservation Biology 12:284-292.