?Weather trumps all
Many sportsmen and sportswomen believe that Montana Fish, Wildlife & Parks controls the state’s fish and wildlife populations. We do, to some extent, through habitat conservation, partnerships with landowners, and regulated hunting, fishing, and trapping seasons. But what plays a far greater role, both in the short term and over the long haul, is weather.
For example, the current long-term drought has lowered stream flows and raised water temperatures throughout much of the state. Fluvial (river-dwelling) arctic grayling have been particularly hard hit, but the drought has also hurt brown, rainbow, and cutthroat trout populations.
A lack of precipitation can also depress waterfowl numbers. During dry years, prairie potholes dry up, depriving ducks and geese of vital feeding, nesting, and migration habitat. But with just one wet spring, many of those dry basins will fill up, again providing excellent habitat.
Snowfall is another huge factor affecting wildlife populations, especially in the mountains. Heavy, early snow forces elk down to lower elevations where forage is still available. Such conditions make elk vulnerable to hunters, especially in the Sun River and northern Yellowstone areas, which creates a much higher harvest than in years with little snowfall. If heavy snows continue through the winter, elk numbers will often decline further due to starvation and the loss of unborn calves.
Mild winters, on the other hand, allow elk to stay at high-
elevation parks, beyond the reach of most hunters. That’s the main
reason for the high elk numbers in parts of southwestern Montana. The same
dry, hot weather that has harmed grayling numbers has allowed many elk herds
in that region to flourish.
Over time, weather changes. Droughts become wet years, and winters of heavy snow are followed by ones with little snowfall.
Elk, trout, and other species evolved with these changing
conditions. If weather was all fish and wildlife populations had to contend
with, they would do fine.
Once humans began significantly changing the
landscape, however, fish and wildlife had new challenges to cope with. Migration routes were blocked
by fences and roads. Naturally beneficial wildfires were suppressed. Dams blocked river fish migration while irrigation and other water use lowered water levels. Unregulated hunting and fishing also took a huge toll.
FWP exists to help manage these human effects on fish and wildlife. And we often succeed, mainly by working with landowners, hunters and anglers, and other conservation agencies to find ways for human use to continue while doing as little harm as possible to fish and wildlife.
But when it comes to the major factor affecting populations— the powerful forces of weather—there’s little we can do besides stand back with everyone else and watch how it plays out.
M. Jeff Hagener is Director of Montana Fish, Wildlife & Parks