|Historic and Current Distribution of Beaver In CA. CDFW Lanman et al|
|Martinez Beavers. c/o Ted Guzzi|
|Kate Lundquist. Martinez Beavers c/o Ted Guzzi|
|Mike Callahan. Martinez Beavers c/o Ted Guzzi|
After lunch we headed off in caravan of jeeps and truck into the Santa Barbara back country for the Santa Ynez beaver tour. The Santa Ynez river is roughly cut in half by Cachuma dam which disrupts steelhead migration into the majority of tributaries and also inhibits the high velocity flows that would characterize this river system. And these two modifications are important to keep in mind. Tim Robinson, who has to balance the needs of fish, citizen water, and downstream water rights, often times is in, shall we say, a bit of a pickle. You see since the majority of good spawning tributaries are cut off by the dam the Cachuma board tries to maintain a nearby tributary and parts of the main channel with year round flows of, if I recall 2.5 cubic feet/second as a compromise to the loss of great steelhead habitat upriver from the dam. Which is a bit funny because, generally speaking, steelhead don't really use the main channel for spawning but as a "highway" to get to the cooler, smaller mountain streams with good gravels. So when beaver dams cause fines to build up, or water does not get to where it needs to go fast enough, or bass, bullfrogs, catfish, and carp proliferate, or flows can not be released to mimic natural flood conditions and blow out dams for water/fish movement guess who gets the blame? Yeah Tim is not as happy with beaver as many who see the benefits of beaver in less modified habits are but Tim has a definite mandate- and that mandate is for the benefit of steelhead and downstream water rights- not beavers. But all the negatives attributed to beavers in this watershed are, if looked at closely, a corollary of the inherent anthropogenic modifications to the system.
The above video is from a beaver dam south of the 154 bridge (so it does not get guaranteed year round flows) and directly upriver from the Encantado pool, a pool which becomes a veritable fish haven and sometimes killing grounds during the dry. Tim's speech and the questions are very pertinent and summarize a lot of the issues surrounding this intriguing watershed. As I mentioned to Rick Lanman later, Santa Barbara needs and can probably afford (hello SB county resident Ophrah) a desalinization plant. You may notice the dour look and vibe of many of the people. The water is low and warm. Not good trout habitat. If alluvial groundwater is not exchanging with beaver ponds due to lack of scouring flows or because of too much groundwater pumping- hyporheic exchange, where cooler subsurface flows intermingle with surface flows, one of the best attributes of beaver ponds - may not be occurring to the extent we should want. But I would not be so quick to assume this drought, and the low flows on the Santa Ynez spell doom for these beavers. Because they have lived here for 80 plus years since reintroduction. Because they live in much warmer/drier climes such as in the Mojave river and San Pedro river in Arizona. Because as I have had to correct several "trained" biologists (even at the conference) beaver do not eat fish, are amphibious but do not need to be immersed in water to live. Just look at these pics I stole from a site about the wildlife of the San Pedro river in Arizona. Read the account here.
Evidently a pair of beavers moved into a stretch of the middle San Pedro that usually flows underground, built a burrow, dug a canal for water, and then went about their business building a dam for flows that were not even there yet!!
|Downstream from den|
|Bank burrow to the left with dug out canal. Pretty much just for drinking water?|
|Another view into the bank burrow|
|But they start making a home anyways...|
|And when the flows returned they had this!!!|
|San Pedro Beavers. like bandits in the night|
Unfortunately, due to time constraints we did not visit the Alisail bridge stop in Solvang. But if you want to see what the beaver are doing there, during high flows from water release I assume check out my post Beaver Safari on the Santa Ynez River from September 2013. I did notice a lot of the dams have that u-shaped berm to them that was commented upon in the video. Also in that section I noticed a lot of the dams only corralled a little side channel of the river- not the whole river.
So don't cry for the beavers of the Santa Ynez, they will get through this. However the steelhead, not so rosy looking for them...
Tim took us to a tributary of the Santa Ynez, Salsipuedes creek- which basically means "get out if you can!" referring to the heavy floods and scouring flows that pummel this creek and incise the banks. It is one of the best remaining steelhead creeks and we saw several fish passages installed. One of which, you can see in the clip below, is often times filled in by a beaver dam. Through no fault of its own, the beaver hears flowing water and sees a great spot to make a dam on a human-modified substrate and conflicts occur. Again, if team human was not perturbing the system there would be no need for a fish passage up a concrete rampart and therefore no need to demolish the beaver dam. Oh team human, why can't you play fair?
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