| |
|
|
| |
What follows are the species profiles of mammals that are found in and around agricultural fields in the Cannon River Watershed. Each species listed includes the description, the status (including range), and the natural and agricultural roles of the mammal. The most abundant mammals, or those with the greatest impacts, will also be listed in each section. |
| |
|
| |
|
| |
|
| |
Insectivores (Shrews, Moles) |
| |
Insectivores, as their name implies, feed primarily on insects, although they will take the occasional small mammal, bird, reptile, or amphibian. The voracious appetites of shrews make them especially effective predators of insect populations. Overall, this group can be viewed as beneficial to agriculture, helping to keep pest insect and small mammal populations down. Of specific note to agriculture is the short-tailed shrew. |
| |
|
| |
Eastern Mole - Scalopus aquaticus
 |
|
 |
| Description |
The total length of the eastern mole is around 171cm (155-185), with a tail around 26cm (21-30). Its fur is dark brown to grayish with a silvery sheen, except on the paws, tail, and naked muzzle. Rarely captured above ground, the best way to identify the eastern mole is by the shallow, raised-earthen tunnels they leave while foraging. |
| Status |
The eastern mole is common in the open areas of southern Minnesota, but reaches its northern limit in central Minnesota. |
| Natural Role |
Eastern moles prey mostly on earthworms, although they will eat other insects that live in the soil, as well as some underground plant parts. They are also important predators of insect larvae. The mole's extensive tunnel and burrow system helps to aerate and turn the soil where they live. |
| Agricultural Role |
Although eastern moles uncommonly inhabit agricultural fields, their presence is not unknown (Waldron et al., 2000). While they help aerate and turn the soil, they can also be pests by injuring root masses, and can be a nuisance in smaller gardens. |
|
| |
|
| |
Masked Shrew - Sorex cinereus
| Description |
The masked shrew has a total length around 94cm (83-104), with a tail around 39cm (36-41), making it one of Minnesota's smallest mammals. It has a pointed nose, characteristic of shrews, and a soft body fur that is dark brown above and dark gray below. The eyes and ears are small and almost completely hidden. It is virtually indistinguishable from the pygmy shrew (not listed here). |
| Status |
The masked shrew is quite common in Minnesota, and ranges from the northern United States throughout Canada. |
| Natural Role |
This shrew will eat a wide variety of adult and larval insects, spiders, centipedes, sowbugs, snails, and small mammals. Due to their small size and strong odor, shrews are not often preyed upon by mammals, although they are eaten by predatory birds. |
| Agricultural Role |
Masked shrews are probably beneficial to agriculture due to the large numbers of insects and mice they consume, keeping the populations in check. |
|
| |
|
| |
Short-tailed Shrew - Blarina brevicauda
 |
|
 |
| Description |
The short-tailed shrew has a total length around 129cm (124-134), with a tail around 25cm (22-27). Similar in size to mice and voles, the shorttail shrew can be distinguished by its pointed snout, tiny eyes, and absence of visible external ears. It has a shorter tail than all other Minnesota shrews. The pelage is variable, but is generally slate-colored. |
| Status |
The short-tailed shrew is Minnesota's most common and abundant small mammal. It ranges throughout north central and northeastern United States and into southern Canada. |
| Natural Role |
One of only two venomous North American mammals, the short-tailed shrew is a very effective and significant predator of insects, earthworms, and small mammals, and will also eat plant matter. The venom is only painful to humans. Few predators will eat them, but they serve as an important prey species to owls. |
| Agricultural Role |
Since the short-tailed shrew is a very voracious eater and is quite common, it can serve as an important check on insect and small mammal pest species in agricultural fields. It even ignores feeding on the beneficial spotted lady beetle (Getz and Brighty, 1986). |
|
| |
|
| |
|
| |
|
| |
|
| |
|
| |
|
| |
|
| |
|
