Cedar Creek Fall 2018 Survey

Post date: Oct 10, 2018 6:9:8 PM

It was a perfect early autumn weekend in Minnesota as trackers and naturalists gathered at the Cedar Creek Ecosystem Science Reserve on September 22 & 23 for our two-day long Fall Wildlife Survey. The stifling heat of the previous weekend and the thunderstorms of mid-week had given way to beautiful blue skies, pleasantly cool temperatures, and ideal tracking conditions on the sand roads and receding mud-puddles throughout the reserve. Over thirty people participated in the survey, bringing in scores of observations of at least 20 different species or genera of mammals, several species of birds, and a smattering of insects and other invertebrates. Here are a few stories from our weekend in the field.We kicked off our survey weekend on Saturday morning with 17 trackers organized into three teams. The teams spent a few hours in the field in the morning, then gathered at Lindeman to eat lunch and share stories before heading back out into the field for the afternoon. The split day allowed more people to explore a broader range of the diverse ecosystems that make up Cedar Creek.

In addition to our regular survey areas, we had a new landscape opened to us this weekend. Cedar Creek's rented bison herd left the Reserve a week before our survey began. For the first time, the enclosure was open for us to explore—giving us a view of how these keystone animals shape the landscape. On Sunday, we were joined by students from the University of Minnesota Fisheries, Wildlife and Conservation Biology Club. With the group now numbering 26, we sent four teams out onto the landscape. Once again, we had teams in the North Unit, on the trails around Lindeman, and near the west end of the bison enclosure, in addition to a team out on the public trails around Fish Lake. Tracking conditions were once again superb, and the weather was even more luxurious—warming into the low 70s under clear blue skies.

On both days, teams found a number of coyote trails in the southeastern corner of the reserve. Though we know that coyote are common in the area, we had seen few tracks we could identify with certainty in our past two surveys. Most of the tracks we found were out in the open on roadways near the bison enclosure. There appeared to be fewer tracks on the wooded roads. Since our own surveys are mostly confined to the roads, we don't know how the coyotes might be traveling off the roads, but they do seem to prefer the open landscape when they are on the roads. The red fox in the same areas, by contrast, seemed to be more active on the roads where there was tree cover. Is this a real division, or just an artifact of our modest sample? If it is a real division, what is the reason for it? And why might coyote activity be concentrated near the bison enclosure? The area is rich in both pocket gopher and deer, and is far from where we usually find wolf sign. But is there more to it than that?

In the North Unit, our teams once again found fresh wolf tracks, perhaps helping to explain the concentration of coyote activity in the southern parts of the property. The tracks we found appeared to all be from a single animal. While we suspect this is the same individual we have been tracking here for the past year-and-a-half, we are not certain. We have photographs of wolf tracks from previous surveys, but the variations in lighting and substrate make it difficult to compare photos alone. Technical drawings of tracks can be more helpful for identifying individual animals. To help determine if this is the same individual we have been seeing in past surveys, identify this individual in the future, and recognize if a different wolf shows up on the Reserve, one team took Saturday afternoon to make detailed sketches of wolf tracks. The technique is time-consuming process, taking well over an hour to draw a single track, but it payed off with a clear outline of the right hind foot of our resident wolf.

Tracking apex predators is always exhilarating, but most of the wildlife at Cedar Creek is smaller and leaves more subtle and delicate tracks. Fortunately, tracking conditions were near perfect on our survey weekend. Most areas had seen little vehicle or foot traffic since the rain, there were a number of mud puddles creating prefect track traps, and overnight dew helped hold the sand on many of the roads together allowing for some very detailed prints. Some of the tracks we saw over the weekend were field guide quality. In addition to our cast of “usual suspects,” our teams found the tracks of meadow jumping mouse and gray fox for the first time. Both are species we believed to be on the reserve, but had never identified on one of our surveys. They gray fox was a particular treat. Two different groups located tracks in two different areas of the reserve. The tracks were very clear, and easy to distinguish from red fox.

Over the course of the weekend, we not only recorded a diversity of species and got a growing sense of distribution, we also deepened our own tracking knowledge. Though our focus has always been on mammals, team members have a growing interest in bird tracks. Over the two days, our teams recorded a large number of bird tracks, identifying many to species with growing confidence. From the narrow, bulbous tracks of blue jays and the slender toed prints of snipe and woodcock to the large and ubiquitous prints of turkey and sandhill crane, our trackers are beginning to distinguish more of the diversity of bird life at Cedar Creek from their footprints. One distinction that we are all learning to make more clearly is that between turkey and sandhill crane. In addition to the differences listed in the tracking literature, we are noting that sandhill crane usually splay their toes wider, and that their claws are much narrower than those of turkeys. These traits have helped us sort out some tricky cases.

The weekend also offered an education in skunk and red fox tracks. Teams began finding skunk trails on the roads around the bison enclosure on Saturday, and recorded several more on Sunday. Though skunks are common at Cedar Creek, we have only identified their tracks a few times on surveys. This weekend, we found long stretches of skunk trails, some showing near-prefect tracks and others showing little more than claw marks.

Lots of activity, plus excellent and constantly changing substrates offered nearly every team a master class in red fox track identification. Some tracks were tight and compact showing all the pads and almost no claw marks, while others were showing little besides claws. Pads sometimes looked small, and sometimes large. Some splayed tracks looked at first glance to be twice the size of tightly registering tracks—but when measured with care proved to be identical in length. And a few tracks registering in fine mud showed incredible detail of the fur on the bottom of the foot.