2016 Spring

One Hole, One Month

For a little over 1 month last semester, some of my research students decided to aim a trail camera at a hole in the ground. we did this for several reasons. First of all, we were interested in finding out if any animals were using the hole, and if so, which species. Secondly, we wanted to know if different species of animals preferred to use the hole only at specific times. Finally, we did this simply because we had an extra camera that we weren’t using on other projects.

The hole, which could be a past or current den, has an entrance that is about 1 ft. in diameter. It measures 2 ft. deep and looks to be around 5 ft. long. There is an old rotting oak trunk that acts as a partial cover. We tallied all of the pictures (371 total) and broke down the animals that “visited” by the hour. A “visit” was defined as an animal that either entered or looked in the hole. The following video shows this hourly breakdown and the percent of visits by each species:

As is evident, the early morning hours (1 a.m. – 8 a.m.) are dominated by opossums and skunks. They tended to alternate hours. From 8 a.m. – 7 p.m., squirrels made the most appearances, by far, with rare visits from several songbirds. A red-shouldered hawk even made a cameo during one evening. Rabbits dominated the 8 p.m. – 10 p.m. The times from 2 a.m. – 3 a.m. (skunk, rabbit, opossum, raccoon) and from 7 p.m. – 8 p.m. (rabbit, opossum, raccoon, squirrel) were the only two range of times when four different species visited the hole.

What does any of this mean? Maybe nothing at all. Or, maybe it means that several different species are efficiently sharing this space. Do the different animals know when the hole is empty and available for use? Do they purposefully avoid conflict with others. We didn’t see any conflicts on camera, but that certainly doesn’t mean there weren’t any. All interesting questions to ask from one camera and one hole.




NewsBits 04- Parasite conservation and humming-not-bird migration


E.O. Wilson has a new book out, and it’s really good. You should read it. As a matter of fact, you should read all of his books. In this particular one, he says that we should set aside half of the planet to conserve biodiversity. You can read a review here.

So, maybe wolves in Yellowstone haven’t yet shown to influence, or scare, the elk population the way they were supposed to. However, maybe there is still such a thing as a landscape of fear. Ed Yong delves into this issue in a recent article, which describes a study done with raccoons.

Have you ever wondered what giant ground sloth burrows look like? If you have, then you’re in luck. The folks from Twilight Beasts wrote about them here. No one is quite sure what these tunnels were used for. Maybe for hiding. Maybe for mating.

Do you see anything strange about this “hummingbird”?









The blind cavefish Cryptotora thamicola has been shown to climb waterfalls with a pelvic girdle similar to a salamander. You can see an interactive model of the pelvis here.

Here are some stunning camera trap images.

Tiny hominids, Homo floresiensis, vanished around 50,000 years ago. This is 40,000 years earlier than previously thought. Could it also mean that they disappeared because Homo sapiens appeared in the region during this same time? see the story here.

Carl Zimmer sits down with Job Dekker to discuss the shape of DNA. There are some really cool animations and applications in this video.

Birds have feathers, but there used to be other animals with feathers. Read about the evolutionary legacy of dinosaurs in today’s birds.

In his latest column, Carl Zimmer wonders if we shouldn’t let parasites and endangered animals continue to live together. He gives an interesting evolutionary perspective to conservation.