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August 28th 10 am.


This week I am going to talk about the American Beaver, Castor canadensis, one of my favorite mammals.When researching the history of beavers in this area I found that there are no written records of beavers living in the Little Lake Valley. This seems strange since the Eel river is connected to the Little Lake Valley through the streams that all eventually drain into it, such as Baechtel, Broaddus, and Outlet Creek. But the fact is, that they are here now, and this year seems to be a very good year for the beaver family we have on the mitigation lands.

Last year we were pleased to find that we had two beavers at work on the southern end of the valley and then this year it looked as if they had moved away, maybe out of the valley. It was with surprise and joy that we finally were able to capture the actions of the beavers on one of our video cam recorders and see that they have not moved away, but have actually been busy raising a family.

Beavers are marvelous engineers and one of the few mammals that significantly alters its habitat to suit its needs. Remarkably this brings about a greater diversity of habitat for lots of other creatures that have evolved with them and that live in wetland environments. There is  research that is showing that the extermination of beavers from many California habitats has been the number one reason we have desertification (the drying out) of many areas that used to be water abundant. Their methods of slowing water down and creating pools of water that last through dry periods is a factor that replenishes the water aquifer. this also creates habitat for fish, ducks, invertebrates, amphibians, and many other species including the Tule Elk that prefer water habitats.

The main concerns that humans have about beavers is the potential for flooding because of their dams and the problem of them cutting down lots of large trees. These two factors have been looked at closely by cities, parks, and Agriculture departments all over the United Sates who are trying to live with and take advantage of having local beavers. An example of this is the town of Martinez, California. Instead of getting rid of the beavers, they decided to find a way to allow them to continue to live in the town. This was not only successful for the beavers but it has become a tourist attraction with a Beaver day celebration!   Other towns and parks have come up with win-win solutions in order to allow the beavers to do their important work. If you want to learn more about some of these and about beavers I recommend the Youtube  called “Leave it to Beavers,” and can be seen at https://www.youtube.com/results?search_query=leave+it+to+beavers+pbsIf   It is a great resource.

Here are some facts about the American beaver that are interesting: it is the second largest rodent in the world. They are well adapted to their environments with valves that allow them to close their ears and nostrils when they are submerged and have a clear membrane that slides over their eyes. One of the coolest adaptations is that their lips form a seal behind their incisors, and this allows them to chew while they are under water without having water and mud enter their mouth. Their tails serve as stabilizers when they are chewing on a tree outside of the water and when they are swimming, besides being a warning to others to stay away when they slap it on the water surface. These are powerful mammals with iron in their sharp long teeth no one wants to mess with. They are monogamous and can live to be 10 to 20 years old. They have “Kits” when they are 2-3 years old and live in groups of up to 8 individuals. Young tend to stay with the group until 2 to 3 years old and help with lodge building and kit raising.

We have not found any beaver lodges in the valley which means that they are either bank burrow dwellers or we just have not found their lodge yet! The dams are easy to find and have created some wonderful pools for other wildlife to live in, such as, Western Pond turtles, Crayfish, and Wood ducks. We are very fortunate that these marvelous animals have chosen to live in our valley!