The Explorers Club, Northern California Chapter

Natural History of Año Nuevo Elephant Seal Reserve

With Mike Diggles, FN-92, U.S. Geological Survey


(PDF of Chapter newsletter available here; 309 K)

See Mike's slideshow from this lecture in its entirety. I finally (3/7/2007) scanned all those old Kodachromes dating back to 1976. Have a look (EC99-10_Ano_Nuevo.pdf; 133 slides, 33 MB).

Año Nuevo Elephant Seal State Reserve is located on Highway 1, 24 miles north of Santa Cruz, 27 miles south of Half Moon Bay. This text is excerpted from the fine reports made available by the State Reserve. Perhaps the most compelling attraction for human visitors to Año Nuevo State Reserve is the large colony of northern elephant seals that assembles here each winter. So named because of their large size and long pendulous noses on the males. These large animals spend most of their lives at sea, coming ashore only to molt, give birth, and mate. The Spanish maritime explorer Sebastian Vizcaino sailed by the point on January 3, 1603. His diarist and chaplain of the expedition, Father Antonio de la Ascension, named it Punta de Año Nuevo for the day on which they sighted it in 1603. New Year's Point.

Hundreds of thousands of northern elephant seals once inhabited the Pacific Ocean. They were slaughtered wholesale in the 1800s for the oil that could be rendered from their blubber. By 1892, only 50 to 100 individuals were left. The only remaining colony was on the Guadalupe Island off the coast of Baja California. In 1922, the Mexican government gave protected status to elephant seals, and the U.S. government followed suit a few years later when the seals began to appear in Southern California waters. Since that time, elephant seals have continued to multiply exponentially, and they have extended their breeding range as far north as Point Reyes.

Today, there are approximately 160,000 northern elephant seals. The first elephant seals on Año Nuevo Island were sighted in 1955, and the first pup was born there in 1961. In 1978, 872 were born there. Males began to haul out on the mainland in 1965. A pup born in January 1975 was the first known mainland birth of a northern elephant seal at Año Nuevo; 86 pups were born there in 1978. By 1988/1989, about 2,000 elephant seals came ashore at Año Nuevo, and the number of seals breeding and giving birth on the mainland is still increasing. During the 1994-95 breeding season, approximately 2,000 pups were born on the mainland. Elephant seal pups are born between December and February. Bull seals arrive from early December through January, to engage in battles for breeding access to the females. Pregnant female seals come ashore to pup from late December through early February. Mothers nurse their pups for about a month, before mating and departing back to the sea. By early March, most of the adults have returned to the sea. Pups remain behind through March and April, basking in the sun and learning to swim. The adult elephant seals return to Año Nuevo’s beaches during the spring and summer months to molt.

Time and place

Date: Friday, October 29, 1999
Place: St. Francis Yacht Club, San Francisco
Time: 6:30 PM cocktails, 7:30 PM dinner, 8:30 PM lecture
Cost: $45 ($50 if received after October 22nd)

About the Speaker

In 1975, the first Elephant Seal "mom" had her pup on the Mainland. Her name was Bertha. Michael F. Diggles, FN-92 met Bertha when she returned in the 1976-77 season and there were about nine pups born on the mainland. Mike has been back to Año Nuevo each of the 23 years since. The photos are from his and Martha Gilmore's collection.

Mike Diggles is a Geologist and CD-ROM Publications Developer at U.S. Geological Survey in Menlo Park, California. He was the lead geologist on the Sierra Nevada Ecosystem Project team and was senior author on the section on geology and minerals issues. Mike received his bachelor's degree from Humboldt State University and his Masters from San Jose State University, both in Geology. He has been with the USGS since 1977 and has produced 91 publications and 12 abstracts. His geologic and mineral-resource mapping as well as his potassium-argon geochronology studies have taken him to Alaska, the Great Basin, and the Sierra Nevada. He has made Congressional briefings on mineral issues and in 1993 received the Department of Interior's Superior Service Award for accomplishments in the USGS Wilderness Program. A recent publication, The October 17, 1989, Loma Prieta, California, Earthquake--Selected Photographs, with John Nakata and other, came out October 8, 1999 as U.S. Geological Survey Digital Data Series DDS-29 (CD-ROM). [update: more recent as of 2001 is a publication on Volcanoes of the Wrangell Mountains and Cook Inlet, Alaska, (USGS DDS-39, v. 1.1) with Tina Neal].

Chapter Field Trip in January, 2000 - Sealabration

On Saturday January 22, 2000 (the day before the Super Bowl, I think), the San Mateo Coast Natural History Association hosts Sealabration, a special fund raising tour to support the educational and interpretive programs at Año Nuevo and other state parks of the San Mateo coast. My plan is for the Northern California Chapter of The Explorers Club to have a field trip consisting of joining this event. The plan is easy: Just phone in your own reservations, get yourselves there, and we’ll meet at the Preserve. You can choose one of three time slots to arrive at the reserve. 8:30 AM-10:30 AM, 10:30 AM-12:30 PM, or 12:30 PM-2:30 PM. But, select the 8:30 AM-10:30 slot because the earlier in the day we go and the colder it is, the more active the seals will be. Then we can all have lunch together afterwards. I have been on these trips the last three years and they are wonderful. The group travels by small bus to the rookery, where the docent naturalists lead you on a special behind-the-scenes walk. Amid more than 3,000 elephant seals, you may witness fights, births, and mating in a unique wildlife spectacle. Complimentary brunch is served in the Visitor Center. Donation is $75, of which $55 is tax-deductible. The toll free reservation phone goes operational November 13, 1998. Reservations are by phone only. You can find out the phone number on the Web in early November at or phone Mike Diggles, (650) 329-5404 (work) or (650) 369-6094 (home).

More information on Año Nuevo Island (ANI) I got this letter from Richard Gantt (Rex Passion) FN98 of the New England Chapter: Dear Mike: I was perusing the Northern Cal chapter of EC just now and saw that you were giving a talk on ANI later this month. As I spent a good deal of time on this tiny island in the early 70’s, I will be interested to see the results of your talk on your website. You also might be interested in visiting my website ( and looking at my pages on elephant seals. Let me know what you think. I will be in Calif. the weekend of 10/21 and hope to do some tagging of great white sharks of Año Nuevo with my friend and former professor, Burney LeBoeuf.

Southern Elephant Seals. Photo by Dana Isherwood.

Southern Elephant Seal; the bulls in this population have less-pronounced chest shields and noses. It is thought that, because the males were hunted more than the females, there was less competition among the males; bulls with these less-pronounced features still were able to breed. Photo by Dana Isherwood.

This is the Last Planned Chapter Newsletter

The Chapter has needed a Secretary for a year and a half. Some of us have filled in and gotten the newsletter out anyhow during that time, most notably Webmaster Mike Diggles, Vice Chair Lesley Ewing, and Chairman Bill Isherwood. As these folks are already overworked with their other duties and a year and a half is a long time, nobody is presently planning to put out any more newsletters after this one. It looks like until such time as the Chapter is able to produce a Secretary, the newsletters will have to be discontinued until further notice. Meanwhile, meetings will be announced by postcard.

Nevada City Weekend last month

The weekend started with a wonderful party at the home of Julia Amaral and Mark Strate and dinner at the Villa Venezia. Julia and Mark were incredibly gracious hosts and provided the early weekend arrivals with a great introduction to Grass Valley history and hospitality. The photos are from Joe Rychetnik

Tour of the Empire Mine, with Pat Murphy, docent and miner.

"My sweetheart’s a mule in the mine
I drive her without any line
Behind her I sit and Tobacco I nip
And upon her behind I do spit"

Pat taught us songs, told stories about the Cousin Jacks, showed us old photographs of the mine, the miners, and the mine owners. The Empire mine alone has over 300 miles of tunnels. It was one of the most productive mines in California, yet all the gold from the mine could fit in a box 7’ x7’x7’.

Saturday Evening Dinner Meeting At the Stonehouse Brewery

Joe Medieros spoke about Alpine Ecology of the Sierra Nevada and other Regions of the World. A subtitle for this talk could be Pennies From Heaven. As we learned from the slide show, the best way to find small alpine plants and flowers is to look for the pennies that so often lie next to the rarest and most picturesque plants. Occasionally, there will be Swiss Army knives, but pennies seem to the best landmark.

Joe and his wife Lynnette are regular visitors to alpine areas — spending 30 days hiking the John Muir Trail and planning their vacations to visit other alpine areas throughout the world. Joe’s term for his type of alpine research Belly Biology since he ends up spending so much time on the ground doing detailed plant studies.

Most alpine plants are perennials that have very complex strategies to survive long enough to propagate. Since many plants must wait 40 to 50 years to store up enough excess energy to flower, the critical elements for these plants are: (1) how to survive long enough to get the energy to flower; and (2) how to make sure your flower will do the job. For the propagation portion, the options tend to be: produce a big flower so the pollinators cannot help but to find it; produce a fragrant flower to attract pollinators; produce a showy flower, like a bright yellow sunflower or a while columbine flower that can be seen by night flying moths; or produce flowers early in the growing season, like many bulbs and the marsh marigold.

Of course all this effort is worthless if there are no pollinators around to notice the flowers. Over time the plants and the pollinators have co-evolved so that many plants can only be pollinated by one or two species. In general alpine areas are buried by snow much of the year and for the brief period when the ground is snow-free, the terrain is often dry, exposed and windy. While plants are struggling to store enough energy to create a flower under these conditions, their pollinators are finding their own ways to survive and play their role in the survival of these alpine plants. Snooze or hibernate through the winter period; cruise or more to a lower elevation; bury eggs that will hatch in the spring; hunker down and wait it out; or store enough food during the summer season to keep going all winter. Despite the adverse conditions of alpine areas, these ecological areas are found around the globe and the same families colonize these areas everywhere. Joe Medieros showed beautiful slides of breath-taking alpine ecosystems around the world and recurring presence of the same plant families and the same survival strategies.

One of our pleasures at the Nevada City event was to present a framed photograph to our retiring Treasurer, Jerry Athearn. The photo of two King Penguins symmetrically facing each other with rookery in the background (taken by Dana Isherwood) was inscribed "The happiest business in all the world is that of making friends." "To Jerry Athearn, From his friends at the Explorers Club".

Future of the next GateAway

From Chairman Bill Isherwood: We held a breakfast meeting in Nevada City the morning following our Saturday dinner, to discuss whether the Chapter was interested in organizing another Golden GateAway. Discussion was frank and animated, with no clear majority opinion on some of the fundamental issues. There did seem to be a consensus that occasional ‘special events’ were worthwhile, but concern over potential financial losses. Many worthy suggestions were made. Some of my own conclusions include:

-- It is probably too late to prepare for a major GateAway in San Francisco for next September/October with the resources available.

-- We may be able to have a lesser GateAway (or other ‘upscale event’) next year, with the Reno/Lake Tahoe area being highly recommended.

-- We should make a strong effort to coordinate to the maximum with other Western Chapters of the Explorers Club, and possibly other organizations (e.g., Society of Women Geographers). This involves possible co-sponsorship and making sure dates do not interfere with other Chapters’ special events.

-- The September/October time frame appears to be our best window, between Summer activities and travels, and traditional holiday season activities and major professional meetings.

-- For anything meaningful to happen, we need broad support of our Chapter members; this means volunteers for numerous tasks -- most of which can be very enjoyable in the contacts made and sense of accomplishment. The key is ‘many hands make light work’.

With this in mind, I am looking for volunteers to help organize such an event. Please call or e-mail me or Vice-Chair, Lesley Ewing.

Texas Chapter Event

From Bill Isherwood: Mike, I just got a response from the Texas Chapter (Don Morley, who send you his regards), who reports that they will be holding their ‘major event’ on one of two weekends in mid-May 2000. Hence we appear to be free to make plans for an upscale event in September or October without interfering with their activities. In the last Polar Times, however, Brain Shoemaker announced that the Polar Society’s next symposium will likely be at the University of Colorado in October 2000. I will check with Brian on his latest plans. If the Polar Society’s plans are not too far along, we may be able to convince them to change their venue to join us in the Reno/Tahoe area.

News From Members

Dr. Gene Savoy writes that the Andean Explorers Foundation and Ocean Sailing Club will hold the 11th Annual "Spirit of Exploration" Awards dinner at the Atlantis Casino Resort, Reno, NV on October 13, 1999. Guests will be treated to the premiere viewing of "Secrets of the Cloud People". For more information and reservations, call (775) 348-1818.

Shannon and Jim Weil wrote that they were sorry to miss the weekend event, but they were moving that weekend to Michigan Bluffs in another part of the Gold Country. Their new address is 29895 Turkey Hill Rd., Foresthill, CA 95631

Joe Rychetnik will have a new book out this October on Hunting and Shooting.

Ron Reuther and Gerry Elkus were travelling in Hawaii, visiting zoos, the Koalawa Lighthouse and Kauii Wildlife Refuge.

Barbara Grigor-Taylor moved recently to Monterey from South Carolina. She and her daughter decided to make the trip an adventure and charted a driving course from South Carolina to Monterey California that never used a divided highway. She will soon be leading a trek to Nepal so her driving practice may come in handy.

Bob Fabry and Susan Taylor are leaving soon for Patagonia on one of the Explorers Club trips.

Jim and Ellen Murphy returned recently from a trip to Alaska where they visited a radar training site on Kodiak Island and saw whales everywhere.

Eve Iversen spent part of the summer in Princeton as a Woodrow Wilson Fellow and will be going to Albania this October for a quick (three day) trip and lecture program on pack animals. She is drafting a Manual of the Use of Pack Animals for Expeditions. Limestone Press published her book, The Romance of Nikolai Rezanov and Concepción Arguello last year and she brought copies with her to the dinner meeting.

Julia Amaral and Mark Strate just joined in a treasure-hunting venture that will try to salvage the Santa Teresa and the Marguerita. She would like help getting an Explorers Club flag for the upcoming expedition to Panama.

Bob and Martha Schmieder provided the next chapter of John Hasslet’s 1999 effort to re-create the voyage of the Kon Tiki. Bob was able to sail for about an hour before he derafted. John and his crew spend about a week off the coast of Equador and he suspected that he attracted some toradoes (?) there. By the time they reached Columbia, much of the raft was eaten away and they landed the raft to go find new logs. After repairing the raft, they got caught in a gyre for about a month and literally sailed around in circles. The Costa Rican Coast Guard finally towed them out of the gyre. John and crew then build another raft and launched it in spite of the storm warning, and again were rescued by the Costa Rican Coast Guard. At this point, John decided that the ocean gods were giving him a message, and he has now returned to Texas. Bob and Martha are about the launch the company Nanologic and hope their launch will be less hazardous than John Hasslet’s.

Don Heyneman (FN-78) was recently in Western Tibet, on a trip led by Dana Isherwood. The group made the kora (sacred pilgrimage) around Mt. Kailas (most holy mountain for Buddhists and Hindus). The kora entails about 50 km of hiking over passes as high as 18,000 ft. The group arrived back in Kathmandu about October 7 after their successful kora around Kailas. They are now off for separate ventures in Nepal for the next couple of weeks. As part of his preparation for the trip, Don joined Dana and Bill (FN-70) Isherwood for a climb of Mt. Langley (14,027 ft) in the southern Sierras. Upon reaching the summit, Don proudly signed the summit register with the statement "I last climbed this mountain 60 years ago, with Norman Clyde" (Norman Clyde was one of the most well known of the early pioneers of Sierra climbing -- Don was 14 at the time). When Dana took off for Tibet, however, Bill had to say his good-byes via phone, as he had gone to Colorado for the Labor Day weekend to climb Capitol Peak. He was able to report success, thus completing ascents of all 68 officially recognized 14,000 foot peaks in the lower 48 States. Bill regrets not having enough vacation time to join the Kailas trip, but is expecting to use all available time on his own climb in Nepal in November/December -- stay tuned for the latest Isherwood adventures.

Greg Sanger introduced his guests and parents Marvin and Maud Sanger who are now living in Grass Valley. Greg’s father worked for many years as a human engineer and helped with the layout of the controls for the B1 bomber and the Shuttle. Greg has been exploring the world of fiber optics and is looking froward to a dive trip to Bali.

Dan Cheatham has been stalking a replicate of Captain Cook’s ship, the Endeavour. He "hornswaggled" (A professional term used by historic ship stalkers) his way onto the press boats in San Diego, Monterey and Coos Bay. In between hornswaggling, he undertook a photographic trip to Macchu Pichu and the headwaters of the Amazon.

Nonna Cheatham completed her third terms on the Board of the Western Aerospace Museum and then enjoyed four days back on Kauai.

Sue Estey and Tom Patterson spend most of February on Kashuri (?) doing coral research and then did a whirl wind "family" visit, where they managed to see 21 relatives in 10 days.

Dave Moyer introduced his guests John and Dr. Abby Givens. Dave and his wife Carol (?) had recently returned from a wonderful and isolated hike to Yosemite’s North Dome. Dave’s guest John had moved to Nevada City in 1985. He provided us a grand welcome to his current home, provided information on all the upcoming events but fell short of passed out Givens for Mayor buttons.

Mike Diggles produced a series of five online publications on the Chi-Chi (Taiwan) Earthquake for Willie Lee and Manual Bonilla (USGS) and Juhn-Guang Liou and L.Y. Hsiao (Stanford) on his Web server, [now at The first of these papers came out under two days after the earthquake. Topics include "Mainshock and Early Aftershocks," "Near Source Accelerograms," "Examples of Near-Source Accelerograms," "Tectonic Setting and Regional Geology of Taiwan," and "A Note on Historic and Quaternary Faults in Western Taiwan."

Greg Miller writes: I’m off shortly to trek/climb in the until-recently closed country of Mustang (aka, "The Forbidden Kingdom of Mustang"), btw Nepal and Tibet in the highlands, on a 3-person expedition I’ve organized over the last year. We are getting local help from associates of Norbu Tenzing, Tenzing Norgay’s son, and we expect to travel in areas well off the "beaten path", where I’m hopeful people (or at least Westerners) have never tread foot. Back in mid-October.

Murat Armbruster writes that ...GlobaLearn’s team is on expedition in South Africa and the WWW site is and has some incredible content. The site has been completely overhauled and I encourage you to check it out. It is amazing what the team has done with it. I look forward to hearing your feedback.

Bill Isherwood, Mike Diggles and Lesley Ewing all reported that the Club needs a secretary. Due to health reasons, Jerry Athearn is looking for someone to take over his responsibilities as treasurer.

To attend the meeting, please make your payment by October 19 (late fee if after Oct. 22) to:

Lesley Ewing
1679 Tacoma Avenue, Berkeley, CA 94707
email to Lesley (

Date created: October 18, 1999
Last modified: March 7, 2007

Web page by: Mike Diggles, Webmaster, Northern California Chapter of the Explorers Club. email to Mike (

c/o U.S. Geological Survey, MS-951, 345 Middlefield Road, Menlo Park, CA 94025. (650) 329-5404

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