Northern Prairie Wildlife Research Center

Figure 1. Habitat maps of plots with centrally
located predator barrier fences. Cropland includes existing CRP cover;
other includes hayland, odd areas such as field corners, planted cover,
right-of-ways, scrub, and woodland. |

Figure 2. Simulated production of recruits on Plots 601 and
701 when amount of the plot fenced varied from 0 - 35%. Plot 601 had 35% grassland
and Plot 701 had 5% grassland. |

Figure 3. Simulated production of recruits on Plots 601 and
701 when amount of the plot in CRP cover in the plot varied from 0 - 35%.
Plot 601 had 35% grassland and Plot 701 had 5% grassland. |

Figure 4. Simulated production of recruits on Plot 701.
Plot had predator fence, and CRP cover varied from 0 - 35%. |

Figure 5. Benefit-cost analysis for adding predator fencing
to a hypothetical 2-habitat plot containing grassland and fenced cover. Straight
lines illustrate cost for obtaining $35,000 worth of ducks given breeding
populations of 500 and 600 pairs. The rightmost end of the curves represent
treating 25% of the plot (A_{t}= 0.25). |

Figure 6. Benefit-cost analysis for adding CRP cover to a
hypothetical 2-habitat plot containing grassland and CRP cover. Straight lines
illustrate benefit and cost at maximum net benefit for a breeding population
of 500 pairs. The rightmost end of the curves represent treating 50% of the
plot (A_{t}= 0.05). |