A major objective of the Fox Creek Land Trust is reintroduction of a sustainable beaver population in the riparian zone. The goal is to reestablish the "well-watered land" that the early settlers observed here. A current article on the benefits of beavers may be found on the web site of the National Parks Conservation Association. Here is information from the Oregon Department of Fish and Wildlife. Here is a recent episode of Oregon Public Broadcasting's Oregon Field Guide that shows a way to jump-start a beaver population. And here is a recent article in the Baker City Herald on beaver reintroduction on the Burnt River in Baker County.
A successful installation will demonstrate that the beaver can coexist with, and complement, economical agricultural and ranching activities. The resultant impact on what is now a high-desert ecosystem can be significant.
A prerequisite is to provide sufficient plantings along the length of the creek to support the beaver population on a sustainable basis. To accomplish this, in 2003, we installed seven miles of fencing to protect the upper two-thirds of the riparian zone from cattle grazing, followed by the planting of 3,800 trees in the riparian zone. This was accomplished with help from the National Resource Conservation Service, U.S.D.A. Farm Service Agency Conservation Reserve Program, Powder River Watershed Council, Oregon Watershed Enhancement Board, Oregon Department of Fish and Wildlife, and the U.S. Fish and Wildlife Service. (see here).
HISTORY OF BEAVER
The beaver, which once kept this a "well-watered land," were virtually eradicated in the 1800's.
According to historical records, before Europeans arrived there were tens of thousands of beaver along the creeks. Ponds created by beaver dams raised the water table, sustained riparian plant life, and prevented erosion from flash floods.
One of the few animals besides man that modifies its environment to any great degree, beaver build dams of sticks and mud across streams and slow rivers. After felling trees along the banks, cutting them into small sections and eating the bark, the stripped sticks are woven into the dam and held in place with mud. They also build large cone-shaped lodges, either in deep water or near the bank. The entrance is underwater but the nest chamber is well above the waterline.(1)
The life of the colony is centered on the lodge and pond. The pond itself has profound ecological effects on the surrounding habitat. The flooding causes the deaths of some trees. The dead trees in turn, provide shelter for various birds that otherwise would not inhabit the place. Water-loving plants thrive in and around the pond, and these provide food and shelter for a variety of animals. The retention of water in the pond causes the local water table to rise, enhancing the growth of additional vegetation. The pond and surrounding wet area acts as a reservoir, preventing rapid runoff of water during rains and ensuing that the stream flows steadily throughout the year. The predictable stream flow allows trout to survive, and further downstream, it allows humans to plan agricultural activities.
When the pond fills with silt it becomes less useful to the beavers, and eventually the colony may abandon the site and move further up or down stream. The abandoned pond gradually becomes covered with meadow grasses, and the resulting lush open area is productive of protein-rich grasses for cattle and horses. This typical beaver meadow, a distinctive feature of the northern mountains, if referred to in Spanish as a vega.
In the early days of American exploration of the Rocky Mountains, the trapping of beaver fur was a principal economic lure. So easy are beaver to locate and trap that by approximately 1900 the animals were largely extirpated from much of the West. When beaver are gone the dams fall into disrepair, the ponds disappear, and the water table falls. Stream and pondside vegetation dies, and the animals that depend on that habitat leave or become extinct. The vegas are no longer good grazing land, and the area looses its value for man. The summer rains, unchecked by he dams, cut deeply into the soil and wash it away. Soon, instead of a fertile riparian community, the streamsides are rock-strewn arroyos that hold water only during occasional floods. Downstream, the farmers leave, now that their irrigation water is a thing of the past. The effect of the uncontrolled commercial exploitation of beaver was a classic example of the public and environmental cost of ignorance and private enterprise. Because the beavers are so obviously beneficial, they were wisely reintroduced to most of the suitable habitats throughout New Mexico and are now widespread.(2)
1.Wassink, J.L. 1993. Mammals of the Central Rockies. Mountain Press, Missoula, p118.