MONTANA
INVASIVE SPECIES


Invasive species harm our lands, waters and native species.

Emerging Threats

Feral Hogs

Feral hogs are domestic hogs that either escaped or were released for hunting purposes. Feral hogs (from Latin fera, "a wild beast") are pigs (Sus scrofa) living in the wild, but which has descended from escaped domesticated individuals in both the Old and New Worlds. Montana is on high alert as there have been sightings up near the Canadian border. Feral hogs are fairly well established in Alberta and Saskatchewan. Impacts associated with feral hogs include:

  • direct competition with livestock as well as game and nongame wildlife species for food;
  • destruction of habitat and agriculture commodities with rooting and trampling activity (for food);
  • destabilization of wetland areas, springs, creeks and tanks by excessive rooting and wallowing;
  • destruction of trees and forestry plantings;
  • prey on fawns, young lambs, kid goats, and eggs of ground nesting birds, such as turkeys and quail.

Feral hogs are very opportunistic feeders and much of their diet is based on seasonal availability. Foods include grasses, forbs, roots and tubers, browse, mast (acorns), fruits, bulbs and mushrooms. Animal matter includes invertebrates (insects, snails, earthworms, etc.), reptiles, amphibians, and carrion (dead animals), as well as live mammals and birds if given the opportunity. Feral hogs are especially fond of acorns and domestic agricultural crops such as corn, milo, rice, wheat, soybeans, peanuts, potatoes, watermelons and cantaloupe. Feral hogs feed primarily at night and during twilight hours, but will also feed during daylight in cold or wet weather. With each generation, the hog's domestic characteristics diminish and they develop the traits needed for survival in the wild. Feral hogs are capable of breeding at six months of age but eight to ten months is normal, provided there is good nutrition.

White Nose Syndrome

White-nose syndrome (WNS) is a disease that affects hibernating bats and is caused by a fungus, Pseudogymnoascus destructans, or Pd for short. Sometimes Pd looks like a white fuzz on bats’ faces, which is how the disease got its name. It grows in cold, dark and damp places and attacks the bare skin of bats while they’re hibernating. As it grows, Pd causes changes in bats that make them become active more than usual and burn up fat they need to survive the winter. Bats with white-nose syndrome may do strange things like fly outside in the daytime in the winter.

White Nose Syndrome (WNS) is a fungus that can be spread by bats, animals or humans carrying spores on their bodies, or in the case of humans, clothing and gear. In particular, recreational cavers traveling from one cave to another can transport the fungus on their boots, ropes or clothing. While there is no treatment for White-Nose Syndrome at this time scientists are working on ways to reduce the lethality of the disease when it does strike. And managers in Montana have the necessary information to prioritize sites for preventative or recovery efforts if needed.

Find more inflation about WNS here.

Salt Cedar

Salt Cedar (also known as tamarisk) is a large shrub or small tree that was introduced to North America from the Middle East in the early 1800s. This weed has been used for ornamentals, windbreaks and erosion control. By 1850, saltcedar had escaped from these areas and infested many river systems and drainages in the Southwest – often displacing native vegetation. Saltcedar continues to spread rapidly and currently infests water drainages and wet areas throughout the United States. It is listed as a noxious weed in Montana and neighboring states. Saltcedar was first found in Montana around 1960 in the Yellowstone and Big Horn River drainages. As of 2017, saltcedar has been reported in 24 counties in Montana (Figure 1). Most of the saltcedar found in Montana is a hybrid of Tamarix species.

Find more information on salt cedar management in the Missouri Basin of Montana/tamarisk here.