Comp Sci 699 Fall 2012
Is it possible to have sustainable population of Wood Turtles while also having a sustainable (continuous) growth rate for the human population in Vilas County, WI?
Time Scale ◦ Refined down to hours. Ticks= Hours ◦ Days, months, years tracked 12/3/12
Turtle Behavior ◦ Daily life: eat, bask, sleep in proper ◦ Mating during proper periods: turtles are male or female, during mating periods females have a chance of being “fertilized” if male turtles nearby ◦ For every “fertilized” female new turtles are spawned into world during proper months; number of turtles based on survival rates past first 5 years (we only model turtles that would survive into adulthood, since there is such a high mortality rate in the first 5 years) 12/3/12
Turtle Behavior (cont'd) ◦ Hibernation during winter ◦ Natural lifespan: ~40 years ◦ Can mate if over 15 years old (sexual maturity) Original population in world starts at age 15 so mating can be observed immediately ◦ Day-to-day survival chance high if not in contact with human development 12/3/12
Human Behavior ◦ Humans move in beginning of each year ◦ If unaffected by policy, prioritize their settlement in following order: Near other humans AND lakes Near lakes Near humans Any suitable land cover (not marsh, water, etc.) 12/3/12
Default ◦ Last place food was found is remembered ◦ Return to these locations when hungry ◦ No more food at location initiates new search Left Leaning walk ◦ Likely the most realistic memory model
Food Zones ◦ Similar to Default ◦ Multiple food locations remembered ◦ Exhausts memory bank before initiating new search Avoid Humans- ◦ Turtles crossing developed patches get confused Intended location lost, random heading ◦ If turtle survives, will remember developed patch as “bad” Will avoid “bad” patches in the future
Passing through developed patch increases chance of turtle death Developed patches can no longer be food sources Using Avoid Humans memory model ◦ Possibility for light confusion ◦ Navigating around developed patches challenging with high Human densities 12/3/12
No Build ◦ Our experimental control for the turtle population ◦ No new incoming humans Free Build ◦ Humans can build anywhere, based on what is most desirable Most desirable: Near other humans AND Near water (lakefront) Close to water > Close to humans 12/3/12
600m Buffer ◦ No new development can occur within 600m of a lakefront ◦ Keeps entirety of Wood Turtle range free of development 300m Buffer ◦ No new development can occur within 300m of a lakefront ◦ Keeps “inner” 300m free from development 12/3/12
Spaced Housing ◦ No new buildings within 180m of each other ◦ Promotes urban sprawl ◦ Ideally keeps corridors open for Wood Turtle movement Grouped Housing ◦ New buildings can only be constructed next to a newly arrived human ◦ Limits urban sprawl 12/3/12
Ran simulation with No Build to analyze Wood Turtle behavior ◦ Runs varied Initial spawn of turtle population random. Problems occurred when near human development Mating population of turtles can not successfully reproduce near humans ◦ Final mean population decreased slightly after 40 year 12/3/12
Is it possible to have sustainable population of Wood Turtles while also having a sustainable (continuous) growth rate for the human population in Vilas County, WI?
Modeled “Current” conditions ◦ Free Build Policy ◦ Default Memory Turtle Population reaches 0 after 71 years ◦ Can not complete lifecycle No basking No nesting sites No food Poor water quality Without change to building policy, there can not be a sustainable populations of Wood Turtles while the influx of humans remains constant 12/3/12
600m Buffer ◦ Turtle populations after 40 years remain comparable to control Slight population increase Most Wood Turtle activity takes place within 600m of water Little human encroachment allows greater stability to the turtle population ◦ May not be feasible to implement Socially unacceptable Push back from public 12/3/12
300m Buffer 12/3/12
Grouped Housing 12/3/12
Spaced Housing ◦ Encourages urban sprawl ◦ More humans and roads Bad conditions for turtles ◦ Success for this policy could increase with better understanding of turtle memory 12/3/12
Future Additions ◦ Integration with GIS ◦ Obtain better data using radio telemetry Map turtle locations over time Window into actual turtle memory Simulating Economy/ Human Satisfaction ◦ Compare versus Turtle population Policy is a tradeoff between the human and turtle factor but we are only really looking at turtles Run the model more realistic turtle population for long periods of time 12/3/12
Add ppt slide with more extensions ◦ Protected lakes/ areas ◦ Differential survival for males and females Females roam farther, subject to higher mortality chance ◦ Point out research needs 12/3/12