Beavers have been on my mind lately, as evidenced in the long post I made about them yesterday. As mentioned in that post, beavers have huge positive effects on watersheds, and their removal has caused drastic effects that we can't even understand the full effects of. I have wondered if beavers were present in some of the more protected perennial streams (or streams that would be perennial with beaver meadows) of southern California. In fact, today I found evidence that in fact beavers did inhabit at least one more wild southern California stream.
Sespe Creek, or Sespe River (really it is a river in winter/spring, and a creek in summer/fall) is one of the most remote and well-preserved wild waterways in southern California. Although quite close to very dense urban areas, the rugged terrain and extreme weather of the Sespe Wilderness has kept most humans out, and allowed it to be a stronghold for species that are rare or extirpated elsewhere, including the California Condor, the Southern Steelhead Trout, and honestly, probably other creatures we don't even know about. This true wild area, often overlooked and very rarely visited, was also a refuge for beavers in the past. In fact, some areas of the vast southern Los Padres National Forest still have a few beavers still surviving - though which if any were continuously present and which were reintroduced is not known.
Because beavers are linked with increased survival of the endangered steelhead trout, because Sespe Creek is prone to intense floods, and just because they were there once before we killed them off, I think it would be an extremely interesting idea to look into the possibility of reintroducing beavers to Sespe Creek. There are difficulties, of course. Beavers don't necessarily eat tamarisk, an invasive species in the area, and it is possible that their presence would spread tamarisk. Tamarisk is also spread by floods though, and beavers reduce floods... so maybe the presence of beavers would actually reduce tamarisk. Maybe tamarisk is even colonizing the creek in response to changes in part associated with the loss of beavers in the first place.
Just something to think about.