Refuge Notebook

Article
Dated December 28, 2001

Unusual mammal may be roaming woods of peninsula

by Ted Bailey

Several years ago, I am 99 percent certain that I saw a mammal not previously recorded -- to the best of my knowledge -- on the Kenai Peninsula. It was in the early fall with a light dusting of snow on the ground.

I was in a vehicle with a witness when this unexpected mammal ran into the middle of the road and stopped briefly to stare at the truck. I got a good look at it. I had seen one like it more than 30 years ago, thousands of miles away. Although this mammal is apparently widespread throughout mainland Alaska, I could find no museum record of it from the Kenai Peninsula. But its distribution maps are shaded on the Kenai Peninsula, indicating its expected presence.

You may be asking, what was this strange mammal? A mountain lion? A flying squirrel?

No, this was a very small mammal -- the smallest of its family. My first impression when I saw it dart out of the brush was that it was an extremely large red-backed vole. But when it stopped in the middle of the road and raised its almost snake-like head, I knew that it was no red-backed vole.

This small mammal had a very long neck, short feet and short tail, and it loped across the road like a little weasel. As a matter of fact, I am almost certain it was a weasel. It was a "least weasel," known to science as Mustela nivalis, the smallest living weasel. I had seen several least weasels years ago while working in the Midwest. They were captured incidentally in small live traps set out by a graduate student that I knew, who was capturing mice and voles for a research project. One least weasel that he caught died in the trap. I obtained the tiny carcass to make a study skin and to save the skull.

The least weasel is not the same as the short-tailed weasel, or ermine -- Mustela erminea -- that we occasionally see and that trappers catch on the Kenai Peninsula. It is much smaller than the attractive ermine. An adult male ermine is about 13 inches long with a long tail, 30 to 45 percent as long as its body. An ermine's fur turns white in the winter, but the tip of the tail remains black. White ermine fur is a fur of nobility in England, and British justices and peers traditionally wear white ermine pelts.

By contrast, an adult male least weasel is only about 10 inches long and has a much shorter tail, only 25 percent as long as its body. Like ermine, least weasels in the north also turn white in the winter, but their short tails are completely white without a black tip.

Least weasels are the champion vole and lemming catchers among mammals because their tiny snake-like bodies enable them to follow the small prey inside their underground and undersnow tunnels. Least weasels are usually found near grassy areas where meadow and tundra voles are common, but they would be adept at catching red-backed voles -- the most common vole -- in our area.

Over the years I have had several people report seeing "baby" weasels on the Kenai Peninsula. But without physical evidence, I was uncertain whether they were indeed baby ermine or the least weasel. Fur trappers are unlikely to capture least weasels, because these weasels are so small that their light weight is unlikely to trigger a trap. Unlike ermine, least weasels are not sought for their fur value.

I thought about reporting my observation to the University of Alaska Museum in Fairbanks, but museums like to deal in physical evidence, i.e., specimens, not observations. So let me address an appeal to our readers for some hard evidence. If your cat or dog brings a dead small weasel with a short tail to your doorstep, or if you catch such a tiny weasel in a trap, please save it and bring it to the refuge office.

A small weasel will easily fit into a Ziploc bag, which can be stored in a freezer. Record the date and location on the bag. Refuge biologists will confirm its identity. If it is a least weasel, they will send it to the University of Alaska Museum in Fairbanks, and your name will be recorded for posterity in the museum's records.

Ted Bailey is a recently retired wildlife biologist who has worked on the Kenai Peninsula for more than 25 years, primarily at the Kenai National Wildlife Refuge. He maintains a keen interest in the Kenai Peninsula's wildlife and natural history.

Previous Refuge Notebook columns and information about the refuge can be found on the Web at http://kenai.fws.gov.