- Author: Kathy Keatley Garvey
The severe California drought--we're in the fourth year--is affecting us all, but it's also affecting insects, says Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at the University of California, Davis.
She writes about "Insects and Drought" in the current edition of the Bohart Museum Society newsletter.
"Californians tend to focus on their lawns and the price of water, but the state's wildlands and animals are also affected," she points out.
Here are some of her observations:
- Drought-stressed trees, such as conifers, "are vulnerable to attack by bark beetles. "The trees are unable to effectively defend themselveswith resin because their oleoresin system is 'powered' by their water-filled vascular system."
- Due to the mild winter (lack of cold temperatures and rain), "houseflies began breeding much earlier, giving their populations an early start" to build up their numbers.
- Due to the drought, wildlife such as skunks, possums, deer, raccoons and turkeys are heading into surburban areas, and bringing their fleas and other parasites. "This is one of the reasons why it's a good idea to keep wildlife away from your home," Kimsey points out.
- Praying mantids emerged earlier than usual this year, and in some areas, are having difficulty finding food. Many immature baby mantids in the foothills starved to death.
- Walnut twig beetles, which in conjunction with a fungus causes thousand cankers disease on native black walnuts, seem to be thriving....the trees "are dying at an accelerated rate due to a combination of water stress and the disease."
So, with the changing weather patterns come the changing insect populations. "Once the rains return, these patterns will change yet again, and again each insect group will react differently," Kimsey said. "Increasing rain, with mild winter temperatures, will have a different effect on insects than more rain and cold temperatures."
Bottom line: "Every year is a new entomological adventure," Kimsey points out. "The more we learn, the less we seem to know about these creatures."
Want to join the Bohart Museum Society and receive the newsletter? And receive other benefits? Check out the society information on the website.
The Bohart Museum, home of nearly eight million insect specimens, is located in Room 1124 of the Academic Surge Building on Crocker Lane, UC Davis. It's open to the public Monday through Thursday (except from noon to 1 p.m.). It's also open on special weekend open houses. For general information, identification of insects, or to schedule a group tour, call the main number at (530) 752-0493. The main email is bmuseum[at]ucdavis.edu. The public education/outreach coordinator is Tabatha Yang (firstname.lastname@example.org)/span>
- Author: Kathy Keatley Garvey
So, pull on your boots, gather your posse, grab your nets and head off to where you think a cabbage white butterfly might be. That would include vacant lots, fields and gardens where its host plants, weedy mustards, grow.
Butterfly expert Arthur Shapiro, distinguished professor of evolution and ecology at the University of California, Davis, has sponsored the annual contest, "Beer for a Butterfly," since 1972. If you collect the first one, and it's verified by judge Shapiro, you'll win a pitcher of beer or its equivalent.
Professor Shapiro says it's too cold out for the cabbage white to fly. "Both yesterday (Thursday, Jan. 1) and today (Friday, Jan. 2) were too cold for even the 'hibernator' Vanessas to come out," he said. "I don't expect rapae before AT LEAST the 13th. By the way, the prognosis looks quite dry through mid-January, but the 90-day outlook is quite wet. In late September, I forecast 130 percent of average rainfall for the season. I'm sticking with that."
Shapiro not only knows butterflies but he knows the weather. His opinion of what's happening with the California weather? (Heavy rains, flooding, heavy rains, flooding.)
"It's a drought. We'd need at least 150 percent, better 200 percent of average seasonal rainfall to get the reservoirs to the point where water managers could undeclared the drought," he said in an email today. "But even if we got that--say with a series of Pineapple Express storms--prudence would dictate releasing some of the inflow to make room for more. It's a crap shoot. This is California, where booms and busts are born. By the way, the snow level has been high so far, so even though the snow is Sierra cement and has a high water content, the pack is mostly above 7500', so the area is pretty small (look at a satellite photo) and no part of the Sierra is carrying more than 50 percent of its seasonal storage capacity."
The "Beer for a Buttterfly" contest is all part of Shapiro's four-decade study of climate and butterfly seasonality. “It is typically one of the first butterflies to emerge in late winter. Since 1972, the first flight has varied from Jan. 1 to Feb. 22, averaging about Jan. 20.”
Shapiro says his long-term studies of butterfly life cycles and climate "are especially important to help us understand biological responses to climate change. The cabbage white is now emerging a week or so earlier on average than it did 30 years ago here."
Shapiro, who is in the field more than 200 days a year, usually wins his own contest. He knows where and when to look. In 2014, he netted the winning butterfly at 12:20 p.m. Tuesday, Jan. 14 in West Sacramento, Yolo County. It ranked as "the fifth or sixth earliest since 1972."
The contest rules include:
- It must be an adult (no caterpillars or pupae) and be captured outdoors.
- It must be brought in alive to the department office, 2320 Storer Hall, UC Davis, during work hours, 8 a.m. to 5 p.m., Monday through Friday, with the full data (exact time, date and location of the capture) and your name, address, phone number and/or e-mail. The receptionist will certify that it is alive and refrigerate it. (If you collect it on a weekend or holiday, keep it in a refrigerator; do not freeze. A few days in the fridge will not harm it.)
- Shapiro is the sole judge.
Shapiro has been defeated only three times since 1972. And all were his graduate students. Adam Porter defeated him in 1983; and Sherri Graves and Rick VanBuskirk each won in the late 1990s.
Shapiro maintains a website on butterflies, where he records the population trends he monitors in Central California. He and biologist/writer/photographer Tim Manolis co-authored A Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions, published in 2007 by the University of California Press.