Friday, August 18, 2017

Peninsula Watershed Photo Friday - Stone Dam

For this Photo Friday, we thought we’d highlight one of our lesser known dams in the Peninsula Crystal Springs Watershed – Stone Dam.





This small dam was built in 1871 approximately two miles away from Pilarcitos Dam (which was constructed in 1866).

Spring Valley Water Company constructed Stone Dam to take advantage of the lower Pilarcitos Creek Watershed. Water impounded at Stone Dam on San Mateo Creek impounds about 5 million gallons of water (in contrast to nearby Pilarcitos Reservoir which can store 1 billion gallons of water).


Happy Friday!

Friday, August 11, 2017

Sightings on the Watershed




Two Double-crested cormorants sun their spread wings to dry during a late summer afternoon on the San Andreas Reservoir. The pastime can be a common site around the watershed. 


Since the black seabirds are at home in both salt water and fresh, the watershed reservoirs provide ample small fish for food. During the spring breeding season, they’ll display the tufted crests they’re named for.  


Friday, August 4, 2017

Life on the Watershed: Bobcats,Young Cubs, and Watershed Health


The bobcat cubbing season is over. But the juveniles will be around for another several months, doing their part to sustain watershed health. 




When the cubs reach 8 to 11 months of age, the mother will evict them from her territory. The medium-size feline is distinguishable by its short bobbed tail. The Peninsula Watershed with its expanse of diverse vegetation is ideal habitat for these
predators, which are big enough to take down small deer but still agile enough to grab darting rabbits and other small animals.

Since they’re so high on the food chain, bobcats sustain a robust habitat by keeping the ecosystem balanced. They weed out species lower on the food chain, which otherwise would increase and overrun  the food resource. Then, while some starve, the rest of the population weakens and the gene pool declines.

It’s an effect that keeps trickling down to lower species, and eventually the plant communities as they get overgrazed. And that deprives critical lower forms, like earthworms--the recyclers. They're the ones that decompose dead leaves and other organic matter into smaller pieces, enabling  stored nutrients to  be  released back into the soil. The renewed soil replenishes the plant life, and the recharge works its way back--to the bobcats and on up.