Prey misidentified

Your readers may recall references to the devastating seasonal effect on the local white birch last August by the birch skeletonizer. This small moth had a peak infestation year resulting in defoliation of many of our white birches.

Biology in our environment is complex. The birch skeletonizer over winters in a pupal stage in the fallen leaf litter. As a result of the peak year this means that there are many pupae hidden beneath the snow.

Mammals may respond to this bumper “crop” of insects by increasing in numbers when food is present. This brings me to the excellent photo of the short-tailed weasel in Thursday’s (Feb. 20) In Focus.

Krissy Wood’s photo captures an exciting moment in her back yard. The caption reads “These are the best mousers out there...” which has merit. The photo however, shows the ermine with an unlucky short-tailed shrew in its mouth.

Shrews are insectivores and this luckless small mammal became prey to the weasel. This winter appears to have been a “good” year for short-tailed shrews, no doubt cleaning up on the insect bounty in the leaf litter.

Shrews are not mice, but in their own special group. Because they eat insect pests they are considered beneficial to man.

Shrews have fine silky grey fur and a pointed snout that houses an array of small sharp teeth. Short-tailed shrews are on the larger side of this group and have been known to prey on mice as well. All small mammals are not created equal.

Chris Blomme
Greater Sudbury