Post Race!

[Shaggy Hiker]

Yeah, I can see how that critique may apply in the case of some species of animal that root around and tear up the ground like wild boars, but cows, really? I can only envision them gently grazing on grass and only causing any problem in areas where the soil cannot support their weight, and they probably wouldn't be too happy staying in conditions hazardous to their balance anyway and would naturally prefer to move to firmer pastures. Also how does their grazing kill fish and make it easier for invasive species to move in?

If your image of cows is a nice green field, picture cows in a desert, as that's what we have. You can't have all that many cows per square KM, because there isn't all that much forage, but there is enough to sustain cows. The soil is fairly fragile, as a single car track across a desert can take decades to fade away (the wagon tracks from the Oregon Trail are still visible where development hasn't wiped them out). So, the hoofprints of cattle will remain for years. Their pies last at least a year, and probably a couple years, too, but they dry out thoroughly, and can probably be used as firewood (it is used in some places).

Streams in this environment are the major location of water, so along streams are the only places where vegetation grows thick and green year round. Trees only grow along the banks of permanent streams, too. The vegetation shades and cools the water, while the streams form undercut banks. Both the vegetation and the undercut banks provide shade and cover for fish, while keeping the water temperatures cool enough for the fish to survive. Once cows get to the stream, they trample and consume the vegetation on the banks. If that was brief, it would be survivable, but unfenced banks are destroyed in short order. All the vegetation goes away, the banks cave in, the water temperature rises, and sedimentation increases. This suffocates the fish, destroys redds, and heats the water to the point where fish can't live there anymore.

One of the biggest challenges we face are getting ranchers to fence off streams so that cows can't get near them. The fact that salmon and steelhead are endangered has made it more urgent, but also somewhat more possible in areas where those species spawn. Generally, ranchers are pretty supportive once they see how much nicer the streams become once fenced, and we've gotten lots of them on board. It's not all that cheap to build cow-proof fences, though, so it's hard to get ranchers to do that on their own. They don't often have huge profit margins. Still, there are lots of fenced off areas around water on public lands grazing, and the water that is protected is dramatically better quality than the water that isn't fenced off.