The newly released National Climate Assessment should be a wake-up for even the ardent skeptics. Climate changes will negatively affect our well-being, economy and our natural resources. The warmer climate here in Montana will have less snowpack, and that diminished snowpack will be gone sooner each summer. Longer and hotter summers mean surface water temperatures will also dramatically increase. For irrigators, a longer, hotter summer with diminished water will reduce crop and pasture production. For cold-water fish, it means more streams going dry, and waters too warm and even lethal for trout, especially for threatened bull trout. These changes will adversely affect the agricultural economy as well as the fishing and tourism economy. It will affect why we live here.
We are too far behind to avoid some of the negative effects of climate change. But we can use available tools to mitigate some effects. From a watershed perspective, care of our headwater streams benefits all downstream water resources, as well as water users. One of the most cost effective, available mitigation tools is restoring beaver in all suitable headwater streams. For too long, we have often relegated this obscure rodent to nuisance status.
Where beaver are present, their dams moderate floods by holding water until it seeps into the streambanks as water storage. Beaver colonies can store 30 percent of floodwater in streambanks to return to the stream later in the summer when it is most beneficial. This water storage benefit is realized both to reduce peak flows, and later in the summer this stored water is slowly released back into the stream. This provides more summer water for both fish and irrigators. The bank stored water is also significantly colder so it reduces the trout bearing waters temperature for trout. A single beaver pond can make some difference, but collectively enhanced beaver activity across Montana can be a huge mitigation measure.
Ag water users are taking notice. Recently a southwest Montana grazing association initiated a beaver transplant onto their grazed drainages because they understand the benefits of beaver to their livestock operations. Yes, there are situations where beaver activity requires use of proven techniques to reduce the inconvenience they might cause.
The dams and ponds the beaver build and maintain at no cost provide benefits to both man as well as wildlife. Moose, in serious decline across Montana, benefit from the enlarged waters and succulent riparian vegetation. Other furbearers, including otter and mink, benefit, as do waterfowl, songbirds and amphibians. Trout, including bull trout, overwinter in the quiet, deep beaver ponds and juvenile trout congregate in beaver ponds.
To ensure beaver can do their work to mitigate climate change, we need to modify trapping regulations and improved streamside vegetation management to assure beaver can occupy habitat. Let’s let beaver do their work.