Archive for March, 2014

The Natural and Cultural Legacy of Yerba Buena Island
Guest Speaker: Ruth Gravanis
7:30pm, Thursday, Apr 17th, 2014
FREE at the Randall Museum, 199 Museum Way, San Francisco, CA 

To thousands of Bay Area residents, Yerba Buena Island means nothing more than the tunnel that connects the two spans of the Bay Bridge. But this little island is one of the Bay Area’s hidden treasures – a fascinating place with remarkable remnants of indigenous vegetation, resident and migratory wildlife, astounding views, and a complex cultural history.

Located only a mile and a half offshore of SF’s mainland, YBI is one of the Bay Area’s least known ecological secrets. Here we can find biological communities that include oak woodlands, riparian and coastal scrub, grasslands, and sandy beach. These habitats support a rich diversity of birds, butterflies and other wildlife.

The island’s human history begins with the First People, who used the island as a fishing camp and burial ground. Ownership, or claimed ownership, of this island-with-many-names passed from a multitude of private parties under Spanish and Mexican rule to the United States – at various times held by the Army, Navy and Coast Guard. The extant “torpedo factory,” lighthouse, and officers’ quarters on the National Register of Historic Places help keep the memories alive.

The speaker is Ruth Gravanis, long-time YBI watcher.

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Living with Mountain Lions

Zara McDonald, President of the Felidae Fund, came to speak with us on February 20th, 2014.

Launched in 2006, the Felidae Conservation Fund does critical field research and conservation with cutting edge technology, innovative K-12 programs, and community involvement. There are 36 felid species, and all are in decline. These species are a powerful indicator species as they are apex on the food chain. They are being killed or dying  by habitat fragmentation, road kill, rodenticide poisoning, loss of genetic diversity, loss of native prey, illegal hunting and trade. Felidae’s education and outreach programs are designed to increase understanding and awareness and thus enable the conservation of  entire ecosystems. The Bay Area Felidae group is BAPP.

There are 40 common names for the Puma/mountain lion. The historic range was from the Yukon to the tip of South America, from sea level to at least 17,000 feet. In 1970 less than 600 pumas were in California. By 1990 the population was 117.

Females weigh up to 150 lbs., males up to 260 lbs. Measuring head to tip of the tail, the tail makes up 40% of the cats length. An adult males needs about 6000 calories a day. A female gives birth after about 90 days and can reproduce when there are 2 years old. Their litter is from 2-4 and the kittens are densely spotted. These spots fade as they grow up. Females need a territory of about 50 square miles, males from 100-400 square miles. They live solitary lives. Life span is 6-13 years.

There are a number of factors that continue to whittle at the number of pumas in the state.

One is depredation, and according to state law, if a puma attacks a pet or livestock in California, the owner can acquire a depredation permit to have the puma killed. In recent years, the number of permits issued has increased to about 100 per year. This number is higher than the sport hunting quotas in the states that allow puma hunting.

In order to help reduce this number, one of BAPP’s goals is to provide better education for pet and livestock owners living at the interface between the developed and natural worlds. Something as simple as keeping pets in at night, or using proper fencing or guard dogs for livestock, can reduce or eliminate incidents such as these, which protects both human-owned and wild animals, reduces community tensions, and minimizes the conflict between humans and the natural world. Rare incidences, 3/year in CA, of pumas being killed when wandering into developed areas are generally orphaned young males who’s mothers were killed and the young male was never taught to avoid humans for their survival.

Another is road kill which leads to the deaths of about 60/year in California. California’s habitats continues to be fragmented by ever increasing number of roads. When pumas cross roads to reach the habitat on the other side, there is significant danger that they will be hit by a car. Given their size this is not only dangerous for the puma but also for the human occupants of the vehicle.

To address this issue, the BAPP team is evaluating puma tracking data from the field research to locate frequent crossing points, especially on Highway 17 which is an especially dangerous road for pumas. Caltrans is now taking a pro-active approach to retrofitting roads with wildlife underpasses, and they have requested the data from the project as it becomes available to help guide their road development activities.

According to the California Department of Fish and Game, almost nine out of every ten reported puma sightings are not actually pumas. They are dogs, coyotes, bobcats, raccoons, deer…. even large house cats.

Though the increase in human-puma conflict is real and needs to be addressed, it’s important to keep in perspective that rather than challenging humans over the loss of their territory, pumas are quietly adapting to the encroachment and destruction of their habitat by adjusting their patterns, and are successfully avoiding conflicts with humans far more than we realize.

For more information and to help please visit Felidaefund.org and bapp.org.

(Thanks to Phillip Gerrie for this month’s notes!)

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Minature Marvels – Portraits in Biodiversity
Guest Speaker: David Liittschwager
7:30pm, Thursday, Mar 20th, 2014
FREE at the Randall Museum, 199 Museum Way, San Francisco, CA 

A Male Pacific Oyster, Crassostrea gigas Whisky Creek Shellfish Hatchery Netarts, Oregon

Photographer, David Littschwager, will share some of his amazing photos from just one cubic foot of SF Bay. This is part of a project that he has taken around the world — photographing what can be found in One Cubic Foot. He’s recently brought this project back home to the Bay Area.

David has been a photographer for National Geographic, Scientific American, Audubon and other magazines, many books, and museums. We are excited to have him here with us.

A World in One Cubic Foot: Portraits of Biodiversity

Photo by David Liittschwager: A Male Pacific Oyster, Crassostrea gigas, Whisky Creek Shellfish Hatchery, Netarts, Oregon

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