Several times a month, Bob Stahmer leaves his home in Stockton and heads to the San Joaquin River National Wildlife Refuge near Vernalis. Armed with a notebook and a camera, he records everything he sees: plants, animals, insects and even mushrooms.
“There are a few species of birds that I’ve probably never seen in my life that I found there,” he said.
Among them are rails, clumsy and shy brown birds. At the San Joaquin River, they like to hide in marsh plants, but they have a unique call, so Stahmer knew they were there.
“Finally, a month ago, I was out there on a calm day and stood still for a few minutes, and one came out of the reeds,” he said.
He may also have spotted a lazuli sparrow, although he can’t be sure. He only saw it for a few seconds.
“It was the brightest turquoise and light blue color I had ever seen in my life,” he said.
For each animal or plant species he comes across, he takes photos or videos and notes where and when he spotted it.
Until the COVID-19 pandemic hit, he was doing the same work in the Lake Lodi natural area. However, as more and more people have turned to the nature trail for safe exercise over the past year, he has gone in search of a quieter place.
Stahmer’s hobby had been in the making for a long time. He graduated from the University of California, Davis with a degree in botany and focused on vegetable crops during his graduate studies. From there, he interned at Heinz – the ketchup and sauce maker, now Kraft Heinz Co. – in Stockton, and that internship turned into a career.
He remained with the company until it was acquired by Berkshire Hathaway and Brazilian company 3G Capital in 2013. At that point he knew his job was in jeopardy and left the company.
Looking for new ways to occupy his time, Stahmer switched from vegetables to wild plants.
That’s when a friend told him he should visit Lake Lodi and check out the nature trail. At the time, Stahmer didn’t even know there was a lake in Lodi.
“You’re pulling my leg,” he remembers telling the friend.
He quickly became a regular on the Lake Lodi nature trail. It’s wilder and nicer than most other local natural areas, he said.
Soon Stahmer’s experience in botany began to surface and he began taking notes and photos of the plants. He also took pictures of the animals and insects, to see if friends or guides could identify them for him. He is a member of the Mycological Society of San Francisco, which helped him confirm the identity of mushrooms and mushrooms he found on his walks.
So when a local graduate student studying local butterfly species invited anyone interested in joining him for the project to attend a meeting, Stahmer went.
The student was studying butterflies at Lake Lodi, specifically the California sister (Adelpha californica) and Lorquin’s admiral (Limenitis lorquini). The two species look very similar, and the goal was to note how many of each they spotted to get an idea of the local population.
The student needed volunteers to take charge of the count for a few months.
“He was going to move to another place that summer,” Stahmer said.
So Stahmer and Kathy Grant, the town of Lodi’s watershed program coordinator, went weekly to count the butterflies. They found that for about 99 Lorquin Admirals they spotted, they saw a California sister.
Even after the project ended, Stahmer continued to take photos and study different species in the Lodi Lake Natural Area. Among its favorites are wood ducks and red-shouldered hawks, deer and foxes. The natural area is home to red and gray foxes.
“They’re very cute,” Stahmer said with a chuckle.
He collects all his research in spreadsheets, with photos and videos when he can.
The video helps him spot things he might otherwise miss, he said. For example, he filmed a kestrel eating a lizard and managed to capture an image just as the lizard’s tail disappeared through the hatch. He also saw an egret swallow a crayfish whole, he said.
Part of its purpose is to note what plants and animals are there at certain times of the year.
Stahmer estimates he has hundreds of thousands of photos at this point, not only of Lake Lodi, but also of the San Joaquin River National Wildlife Refuge and a few other sites in the area.
(He once saw a burrowing owl near Isenberg’s Crane Preserve on Woodbridge Road, for example; he spotted the owl nestling, looking around, and captured it on film.)
Once the pandemic is over, he hopes to be able to share some of his research with the Lodi Lake Docents.
In the meantime, Stahmer has settled into his routine of visiting the San Joaquin River, where he has already collected more than 60 folders of photos and videos. He also set up a trail camera that spy on local wildlife in the absence of humans.
He saw all kinds of animals there: cranes, white pelicans, American coots, quails, western lizards and even a coyote.
“He wouldn’t come up to me and let me pet him,” he laughs.
He tries to spot one of the endangered brush rabbits that lives in the area. He’s seen rabbits from a local restocking program released there before, and he’s even been able to release one himself, but he’s yet to spot one in the wild.
“I saw rabbits, and I saw jack rabbits,” but no brush rabbits, he said.