Cedar Creek Summer Science!

Our new data upload brings you the spring and summer seasons at Cedar Creek. In addition to brand new fawns, emerging bears, and beautiful green foliage, you’re also probably getting a bunch of pictures of researchers and our strange equipment. Who has seen these fenced exclosures set up in front of a subset of our camera traps? What are those all about?!

We set up those enclosures to help study how wolves affect ecosystems. If you’ve checked out any of the “About” information on our website, you may know that one of the reasons we set up this camera grid in the first place was to study the recolonization of wolves to Cedar Creek and the effects that returning predators might have on their ecosystems. Predators like wolves can change animal and even plant and soil communities through two possible pathways. One way is by consuming herbivores, like deer, and thus reducing the number of deer going around eating plants. But predators can also scare their prey in ways that changes how those animals interact with their environment. If you’re a deer and you know that wolves tend to hang out in certain parts of Cedar Creek, you might stay far the heck away from those areas, right? That means that those specific spaces are released from deer herbivory and those plant communities will grow in different ways from plant communities in “safe” places that deer still feel comfortable visiting. These two mechanisms likely work in concert, but scientists currently don’t have a clear understanding of the relative strength of these “consumptive” and “non-consumptive” effects of predators on their environment.

Because there aren’t currently any resident wolves hanging out in Cedar Creek full-time, this gives us an excellent opportunity to isolate and test the strength of “non-consumptive” (deer-scaring) pathway. Experiments with bugs and fish conducted in laboratory settings suggest that this effect might be the strongest way that predators shape their ecosystems, often stronger than the effect of actually eating prey! (Why would this be? Think about this: the only individual who is affected when predators kill prey is the one that gets eaten. However ALL prey in a population are afraid of being eaten by predators, and the behavioral changes of the entire population of prey can add up!). But in these small-scale experiments, predators were caged or even had their mouth-parts glued shut to take away their ability to eat, leaving only the cues of their presence to scare prey. Of course, we can’t and won't go out and start gluing wolf mouths shut here at Cedar Creek! Instead, we indicate wolf presence in areas where wolves don’t currently live to see whether simulated wolves induce a behavioral response in prey that is strong enough to trickle down and affect plant and soil communities.

The way we went about simulating wolf presence was pretty simple: I went online, ordered GALLONS of wolf urine (you can buy anything on the internet these days!), and once a week, I went out to a subset of our camera trap sites to sprinkle around these indications of wolf "presence". (Wildlife biologists have done crazier things: Dr. Joel Berger used to dress up in a bearsuit to try and scare musk oxen!). There was another set of camera traps that I visited to sprinkle water, as a control treatment. At all of these sites, we built a series of herbivore exclosures – little fenced sections where deer couldn’t get in and eat any plants. We could then compare plant and soil dynamics between the “predator” and control treatments, and between treatment and control areas (exposed grazed areas vs. ungrazed fenced areas). Combined with camera records of deer activity and visitation rates, we can test whether the risk of being eaten by wolves alone is strong enough to affect entire ecosystems.

We just finished our first year's worth of research, have crunched some numbers, and are looking at our results right now! Stay tuned for exciting revelations from the Cedar Creek Wolf Project, and keep your eyes peeled for your favorite researchers and interns hard at work! If you're lucky (or unlucky?) maybe you'll get to see the wolf urine sprinkling in action!