Home»Jasper Ridge Galleries»A Day at a Time: Individual Visits»7/2/2025 Insect Traps at Lower and Middle Searsville Lakes

Hilary Bayer, a researcher from UC Santa Barbara, has set a dozen insect traps near Lower and Middle Searsville Lakes. Four groups of three, two groups on each lake. In each group, two traps are near the lake, the other up a bit, perhaps out of the insect regime set by the lake. As you can see, the traps are hollow tents: crossing black mesh below, white fabric above funneling to a collection bottle at the apex. When flying insects hit an obstacle, their instinct is to fly up and over. Above is bright white – sky? They end up in a clear plastic enclosure at the top, then bounce around until ending up in a bottle of ethanol. (BTW, if you set such a trap in bear country, be aware that bears *love* ethanol. Don’t set the trap in the same place after the bear has destroyed it – bears remember where good stuff can be found.)

Hilary let me accompany her on her rounds, as she changed the sample bottles and checked the traps. We discovered that these traps are a boon for spiders, forming a nice insect funnel to a well-placed web. Shooing spiders and cleaning webs became part of the job. (And accounting for the spider effect could add complexity to data analysis?)

What a special time to be out, walking down to the dam in the morning! Still air, quiet sunlight. Clouds of little birds accompany us, flitting tree to tree. As we cross the dam, a shy Brush Rabbit wonders if we are a threat, finally deciding on its first option when danger appears: freeze. Its soft ears host colonies of ticks. A good morning to be out, overall.

{Hilary and her sister Jen are the organizers of the 2018 Silicon Valley Barcode of Life event at Hidden Villa, and the authors of “Biodiversity at Hidden Villa: Farm and Wilderness Arthropod Life”. <https://sites.google.com/view/siliconvalleybarcodeoflife/biodiversity-at-hidden-villa?authuser=0> This is a wonderful book, especially if you like arthropods. It has extensive information and photographs of the arthropod subclasses and phyla collected at Hidden Villa. From the link you can get a free PDF or order a printed book. Full disclosure: some of my photos are in the book, and many from our Jasper Ridge community contributed to the study and book; the acknowledgments cite Jack Owicki, Rodolfo Dirzo, Elizabeth Hadly, Tadashi Fukami, Harold Mooney, Nona Chiariello, Pierre Martineau, Merav Vonshak, Sara Witt, and Jerry Hearn among many others.}