SF Natural History Series

David Liittschwager’s idea of one cubic foot partly started with the idea of having a manageable sample size (the talk was given March 20th, 2014). It is not an uncommon practice to find a limit around observations. So looking at a one cubic foot volume for visible species collecting at different times to find representatives of one day’s time. The size also reflects a common collecting practice of using 5 gallon buckets for collecting, and it is a similar volume.

But in has not turned out to be very limiting. The “dirty secret” for David is that he’s never really finished cataloging within those limitations. The biodiversity that can be found is amazing if we take the time to look. Even a pile of leaf litter in new york city turned up 100 species.

The spots to which he went were chosen by the likes of E.O. Wilson for the biodiversity they know is present. And the most spectacular of these locations have been tropical reefs. He flipped through amazing photo after photo of creatures collected from this little space and carefully sorted out to be identified and photographed.

All those creatures aren’t there all the time of course, but things move and water flows over the reef and through the open skeleton of one cubic foot. Collecting at different times of day and night then going through the process of sorting and identifying and photographing. It took about a month to come up with a representative sample of 24 hours. 

David looked up with some chagrin at a leafy acquatic plant, and said they should have spent time looking through the leaves, they would have found a ton more.

More recently he was out just at the mouth of the San Francisco Bay 100 yards west of the GGB, 100 yards south of the north tower, seeing what pass through a cubic foot of water as the tide moved in out, pulling in with a 300 micron net: mites, water fleas, tons of cephalopods, algae, crab and fish larvae, skeleton shrimp. With an 80 micron net they pulled in the glistening forms of diatoms. On a back of the napkin calculation, in a normal 24 hour period of spring tide, nearly a quarter million linear feet of water would pass through that cube — and maybe  2.6 billion creatures would flow through that space. 

David’s work in these small spaces shows us a different magnitude of beauty and grandeur, life, diversity, and abundance at scale we would not expect. Another lesson in all that we do not know about the planet we inhabit.

Find out more about David Liittschwager’s work at liittschwager.com.

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!)