Beavers Along the San Pedro River- The History and Importance

Cochise County is home to tons of unique wildlife, such as bobcats, frogs, ocelots, javelina, and more. But did you know dozens of beavers can be found along the San Pedro River? Beavers in Arizona and Mexico play an important role in the San Pedro River's ecosystem. How long have the beavers been around, and what makes them so important for Cochise County?

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The San Pedro River

The San Pedro River has been around for centuries, and is roughly 140 miles long. This river is home to over 350 species of birds, 80 species of mammals, over 100 species of butterflies and other insects, and 40 species of reptiles and amphibians. Not only that, but over 70 percent of wildlife rely on the river for survival.

Beavers are a huge piece of this river's ecosystem, and have been spotted along the river for centuries. When the San Pedro was first discovered by James Ohio Pattie and his comrades in March of 1825, they called it the "Beaver River" due to the abundance of beavers along the river at the time. James Pattie was sighted as saying, "About every five miles there is a beaver dam. This is a great Country for them." This may come as a shock to people who are familiar with the river, because beavers don't seem all that common anymore, and there is a reason for that.

READ: Why Bats Are Key To Arizona's Ecosystem Health

Conservation Efforts

When people first started to move to the frontier, beavers were a very common animal you'd find in the area. Today, the beaver population is below 40, and it is extremely rare to see a beaver along the San Pedro River.

After the beavers were discovered in 1825, beaver trapping became a common occurrence. By the mid 1900's, the beaver population disappeared completely, and the river suffered dire consequences. The wetlands nearby dried up, and natural dams along the river disappeared, changing the way the river flowed. Throughout the rest of the century, researchers in the area did their best to manage the river and reintroduce the beavers. 

Bureau of Land Management reintroduced 40 beavers to the San Pedro Riparian National Conservation Area in 1999. In 2010, the beaver population was close to 100, and then researchers noticed fewer and fewer beavers in the river as time went on. Today, there are roughly 40 beavers along the river, and hundreds of citizens volunteer to survey the beaver population and manage dam building along the river. Biologists in the area hope that with new conservation methods being developed, the beaver population will regrow on its own.

RELATED: The Decline Of Jaguars In Arizona: A Growing Concern

Benefiting the Ecosystem

We know that beavers were once found in the area, but why is it so important that we bring them back? Well, beavers play a critical role in maintaining the health of the San Pedro River's ecosystem. By building dams along the river, the beavers slow the flow of water, allowing it to have time to soak into the ground. They also recharge groundwater, reduce erosion, and keep surface water available longer during dry seasons.

Not only that, but beaver dams help develop wetlands near the river that promote plant growth and support several animals like frogs and migratory birds. When the beaver population originally disappeared in the late 1800s and early 1900s due to heavy fur trapping, the river began to change rapidly. Without beaver dams to slow and spread water, channels deepened, wetlands dried up, groundwater levels dropped, and large areas of riparian habitat were lost. Without beavers, the river ecosystem is extremely threatened. 

If you are interested in learning more about the local beaver population and what you can do to help support the conservation efforts, visit the Friends of the San Pedro Facebook page to learn about volunteer opportunities. You can also visit the City of Sierra Vista's website to get updates on events regarding research on the beaver popu;lation.

CONTINUE READING: Exploring The San Pedro Riparian National Conservation Area