To the south of Pleasanton, the Sunol Wilderness Regional Preserve is home to a number of distinct critters significant to the native ecosystem. This summer, the East Bay Regional Park District has made an effort to highlight those creatures and their habitats through tours and activities.
Naturalists of the Sunol park are hosting a series of outdoor educational sessions focused on the native animals of the area — namely the local bats, birds and scorpions that inhabit the park.
"Bats play a really important role in the ecosystem. All over the world they are helping us, from seed dispersal to pollination," park naturalist Ashley Houts said when discussing the native animals.
Houts has worked with the bats throughout her time at the park, explaining how they play a vital role in agriculture and human living. Bats function as pollinators and seed dispersers, and they are even known to protect cash crops by eating harmful insects and pests.
"Here in the East Bay, they help us out by eating their favorite meal -- bugs," Houts said. "There is one bat in our area that can eat as many as 1,000 mosquitoes in one hour. By eating all of those insects, they help us to prevent disease from spreading and also help us to use less pesticides. Bats are amazing creatures."
More than a dozen varieties of bat species are found in the greater Bay Area, with over 1,400 worldwide. The nocturnal flying mammals have an array of characteristics that allow them to thrive in the park, such as echolocation and hyper-hearing.
Naturalists say they aid in preserving local habitats and can help to slow down the effects of climate change.
Pallid bats and Townsend's big-eared bats are two of the main species at the park. According to EBRPD naturalists, these bats are able to eat up to 50 times their body weight in one night. Pallid bats are known to regularly feast on scorpions for meals.
Houts explained that both species are threatened.
"With only having one baby one year, bats have a relatively low production rate," Houts said. "One baby is not as many as other mammals would have in the wild, and they face other dangers, like climate change and wind farms."
Houts encouraged local residents to visit their nearest regional park and to support bats in any way they can.
"Other things you could do (to help bats) are planting plants that attract nighttime insects, such as evening primrose or dahlias," Houts said. "This summer, take a night hike and go camping in your East Bay regional park, and do something to help give bats a wing-up."
Visitors can attend future "Bat Watch" sessions at the Sunol park on Aug. 16 and Aug. 30.
To highlight the native birds of the park, naturalists offer daytime guided walks for visitors. The tours welcome both experienced and new birders alike. Topics discussed are behavior patterns, habitats and migration of the local animals.
EBRPD naturalist Erica Stephens has led previous bird watching tours at the Las Trampas Wilderness Regional Preserve in San Ramon. She shared tips and tricks for spotting the birds during a session.
"The key to successful birding is to start simple and to take your time. Use a smaller, more basic field guide at first. Also, focus on size and color to help figure out what bird you're seeing based on its size," Stephens said. "If the bird is smaller than a crow, it might be a raptor, which is a bird of prey. Larger birds tend to be easier to spot and identify."
Although not necessary, officials recommend using a pair of binoculars.
The western bluebird, which ranges from Southern California to Washington state and through parts of the south western United States, is known to inhabit the Sunol park.
Spotting the bird can be fairly rare, according to park naturalists.
Other more common birds of the Sunol Regional Wilderness are acorn woodpecker, dark-eyed junco, black phoebe, white-crowned sparrow, California quail, turkey vulture and red-tailed hawk.
The presence and behavior of each bird species can vary significantly, Stephens explained.
"There are alot of factors involved with birding. Different seasons bring in different birds to the bay areas as others migrate away," Stephens said. "Certain birds prefer their own unique habitats, like shore birds along the coastlines, tree dwellers and more."
Houts further discussed the behavior of the acorn woodpeckers common in Sunol and are also visible at the Briones Regional Park. These birds are known to leave dime-sized holes into trees on the land, mostly to hide and store acorns in them.
"Woodpeckers peck the bark of trees for so many reasons, sometimes they're looking for bugs to eat, other times they're looking to drain the sap from the trees for a treat," Houts said.
"Acorns are the nuts that grow on oak trees, and every different oak tree here in the Bay Area makes a different size and shape acorn," Houts said. "The acorns fall to the ground in the autumn and that's when these acorn woodpeckers collect all the acorns they can and (begin) storing them in the trees."
Using long and pointy bills, the birds poke holes into the trees.
"Acorn woodpeckers work together in large family groups to bring all the acorns in and store them," Houts explained. "Every year they use the same tree over and over again, we call them granary trees."
In addition to the bird and bat sessions, naturalists including Stephens will also lead "Scorpions of the Night" -- a guided search for the small fluorescent creatures at the park.
For these sessions, park staff recommend visitors bring headlamps, flashlights and wear closed toed shoes. Scorpion sightings are not guaranteed.
"It's great to have folks go outside, get involved with their nature community and learn about the native animals we have here," EBRPD spokesman Dave Mason said.
Sunol Wilderness Regional Preserve is managed by the EBRPD, a system of outdoor recreation areas maintained and regulated by the public agency. To find out more about the Sunol park and its upcoming activities, visit www.ebparks.org.