LITTLE ROCK (AGFC) - In a recently published research paper in the Journal of the Arkansas Academy of Science, researchers announced the identification in the Arkansas Ozarks of a species of shrew not previously known to exist in the state. The northern short-tailed shrew, which is generally distributed in the northern United States, was found in Madison, Newton, Pope, Sharp and Van Buren counties.
The northern short-tailed shrew is a small mammal, a little over 4 inches long, that is usually found in hardwood forests with deep leaf litter, but is adaptable to living in a variety of habitats. They usually eat worms, slugs, insects and occasionally even mice.
Back in 2010, Idun Guenther, a graduate student at Arkansas Tech University was studying small mammals on the Buffalo National River along with Matt Connior, of South Arkansas Community College. After catching the animals, the two decided that it would be a good idea to use the shrew's DNA to determine which species they are, since many shrews look very similar to each other.
They sent samples to Dr. Russell Pfau of Tarleton State University in Stephenville, Texas who discovered that one of them appeared to be the northern short-tailed shrew, which had never been found in Arkansas. "I was very surprised to get a DNA sequence of northern long-tailed shrews from one of the two specimens. In fact, I assumed it was a mistake of some kind," Pfau said. With additional specimens provided by Guenther and Connior, he was able to confirm their presence. However, the question remained as to how widely they were distributed across the state.
Pfau contacted Blake Sasse, the nongame mammal biologist for the Arkansas Game and Fish Commission, for help in finding more specimens. "I just happened to still have dozens of shrews that were collected as part of a statewide project to study small mammals that was conducted on Wildlife Management Areas from 2002 to 2004," Sasse said. With this additional information the team was able to conclude that the northern short-tailed shrew seems to only be found in the Ozarks region of Arkansas. They also were able to confirm the presence of other shrew species in Arkansas counties where they had not previously been captured, but were known to occur in other parts of the state.
While Arkansas has gained a new species of shrew, it appears that it may have lost one as well since no Elliot's short-tailed shrews were found as part of the study. It's possible that this species never actually lived in Arkansas and that northern short-tailed shrews caught in the past were misidentified as Elliot's short-tailed shrews based on a limited examination of some of their skeletal characteristics. "This study highlights the importance of collecting specimens and maintaining them, along with their tissues, for future study. It also demonstrates the growing use of DNA technology in better understanding the diversity of living organisms," Pfau explained.