Weight’s Effect on Predation May 31, 2007 Sandra Archibald, Lindsay Camm, Kenny Limber, Bhumit Patel

Where and When? The project was performed on Thursday May 24, Friday May 25th, and Sunday May 27th Performed outside of SAHB Building near Lake Garnett Dogs were brought in on separate days Same quadrant was used for each individual

Materials Different breeds and ages of dogs on leashes Two boxes or Purina Brand Milk bones for Small Dogs 1 clipboard 1 helper person 2 stop watches (one for 5 minute time and 1 for handling time) 1 pen 1 tape measurer that does at least 20m 4 flags to mark off quadrant ( or trees ) 1 bottle of water for recorder to drink

Methods Dogs were left on leash to complete project Dogs “hunted down” the prey in the 10m x 10m quadrant Three handling times were recorded per dog Counted the number of treats eaten in 5 minutes Recorded the weight of the dog before experiment began The control in this experiment was the weight of the dog

Gabriel Hunting for treats

Map

Prey Consumed Observed Data 1/Pc Weight Prey Consumed Observed 1/Weight expected Pc Expected 101 16 0.0099 0.0625 0.0656 15.2407 86 0.0116 0.0672 14.8840 70 14 0.0143 0.0714 0.0696 14.3666 67 9 0.0149 0.1111 0.0702 14.2474 17 0.0588 63 18 0.0159 0.0556 0.0711 14.0744 58 15 0.0172 0.0667 0.0723 13.8319 48 13 0.0208 0.0769 0.0756 13.2333 26 0.0385 0.0916 10.9152 8 0.1250 0.1173 8.5256 6 0.1667 0.1216 8.2218 10 0.1000 0.1266 7.8970

Results

Comparing Two Values Pc Expected 15.24 14.88 14.36 14.24 14.07 13.83 13.23 10.91 8.52 8.22 7.89 Prey Consumed 16 14 9 17 18 15 13 8 6 10

Closeness of Two Values

The results shown on the graphs illustrate that the experimental data is consistent with the expected data. As the predator weight increased, the amount of prey consumed increased as well.

Our Hypotheses Null Hypothesis: There is no relationship between the weight of a predator and the efficiency of a predator. Alternative Hypothesis: Predator efficiency varies between different weights of predators.

The Results Support... The results show a correlation between predator weight and the amount of prey consumed. The data accepts the alternative hypothesis and rejects the null hypothesis. A correlation can be drawn to show that the more a predator weighs, the more prey it can hunt and consume.

Possible Sources of Error Some dogs may have had a preference for different treats (a.k.a. prey). Because of the dogs’ schedules, subjects were tested on different days. Environmental factors may have played a part in predator behavior on various days.

For Further Experimentation... To improve this study, researchers could increase the number of subjects to make the results more reliable. All subjects could be tested on the same day. More factors could be taken into consideration like the breed of dog and the size of the predator’s mouth.

In Conclusion... A positive correlation has been made between predator weight and the amount of prey consumed in a given time. We conclude that larger dogs are more efficient predators. They have larger appetites, requiring more prey to be consumed before they meet satiation. They generally have larger mouths, allowing them to eat faster. Larger dogs utilize their time better to find as much prey as possible.