The circle of life...
Monarch caterpillars feast on milkweed, their host plant. Oleander aphids feast on the juices of milkweed plants. Lady beetles, better known as ladybugs (but they're beetles, not bugs) feast on the aphids.
The milkweed is the only plant that the monarch caterpillars eat. Oleander aphids, as their name implies, are also commonly found on oleander. And lady beetles not only eat aphids, but soft-bodied insects such as scales, white files, mites, and yes, monarch butterfly eggs.
The UC Statewide Integrated Pest Management Program (UC IPM) says California has some 200 species of lady beetles and that "most are predators both as adults and larvae."
If you've ever watched a lady beetle go through the aphid cafeteria and select the menu (big, little, small, winged, wingless, fast, slow, near, far), it's quite a sight.
One lady beetle can eat 50 aphids a day, scientists say. During its lifetime, that can mean 5000 aphids.
As for the oleander aphids (Aphis nerii), they derive their name from Nerium, the genus name for oleander. Both are the oleander and oleander aphid are reportedly native to the Mediterranean region.
If you have milkweed, you probably have aphids. Oleander aphids. And you probably have lady beetles eating those aphids. And the monarch eggs...
The circle of life..
Dragonflies are fierce predators but they are predator-shy.
"If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck," as the saying goes. If you look like a predator, walk or fly like a predator and act like a predator, that dragonfly perched near you will take off.
The other day a variegated meadowhawk dragonfly, landed on a bamboo stake in our yard. It was identified as a "mature female Sympetrum corruptum" by dragonfly expert Rosser Garrison, a senior insect biosystematist in the California Department of Food and Agriculture's Plant Pest Diagnostics Branch, Sacramento, and by naturalist Greg Kareofelas, an associate at the Bohart Museum of Entomology, University of California, Davis.
How do you "catch" a dragonfly, that is, get close enough to photograph it? It helps to have a professional camera, fast shutter and a long lens, like a 200mm. Sometimes you can photograph them with a 105mm lens. To get this photo, I pretended to be part of a butterfly bush. I left my tripod behind and edged slowly, closer and closer, camera poised at the ready (a sudden movement and the dragonfly will be in the next zip code), focused, and clicked. A stiff breeze draped her wings over her head as if she were playing hide 'n seek.
Oftentimes, I'll sit in a chair and wait for them to return to the perch. They often do.
You can also drop to the ground (make yourself look little and uninterested.)
"Just as the sun was setting last night, I noticed many dragonflies flying in my backyard," Kareofelas said. "They were flying very quickly and very high, but every so often one would swoop down and land. When they do, you can approach slowly and get close. When you approach a perched dragonfly, slowly stoop as you get closer. Many times, if you do not appear larger as you get closer, the dragonfly does not realize you are getting close."
The variegated meadowhawk is one of the dragonflies on a Bohart Museum of Entomology poster, the work of entomologist Fran Keller and Kareofelas.
Its habitat ranges from throughout much of the United States to British Columbia and Canada. It's found as far south as Honduras, and as far west as eastern Asia.
It hangs around ponds, lakes and swamps to catch its prey. if you don't look, move or act like prey, you, too, can "catch" a dragonfly.
With your camera...
Chemical ecologist Yuko Ishida of Toyama, Japan, a former UC Davis post-doctoral researcher who shared the same lab--and the same bench--in Briggs Hall that Duffey did, is the lead co-author of a cover story recently published in the Proceedings of the National Academy of Sciences (PNAS) about an invasive species of millipede that secrets hydrogen cyanide as a defensive mechanism. (See research paper)
Ishida and Duffey never met but they shared a love of science and chemical ecology, in addition to the same lab.
At the time of his death, Duffey was a professor and vice chair of the UC Davis Department of Entomology. When chemical ecologist/professor Walter Leal joined the UC Davis Department of Entomology faculty in 2000, he occupied the former labs of professors Duffey and Susumu Maeda (1950-1998) and memoralized their lives and work by naming his lab the “Honorary Maeda-Duffey lab.”
Ishida worked in the Honorary Maeda-Duffey lab from May 2001 to November 2007 at UC Davis.
“Yuko loves to tackle challenging problems and he is well prepared to solve them,” said Leal, former chair of the UC Davis Department of Entomology and now with the UC Davis Department of Molecular and Cellular Biology.
Ishida also photographed the millipede, found in southern Japan, for the PNAS cover.
The four scientists all work at the Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, and are affiliated with the Asano Active Enzyme Molecule Project, Exploratory Research for Advanced Technology, Japan Science and Technology Agency, Toyama.
“To discover more efficient and stable HNLs, we focused on the invasive cyanogenic millipede as a bioresource,” the scientists wrote. “The HNL identified from the millipede showed not only the highest specific activity toward benzaldehyde among known HNLs, including the almond HNL in industrial use, along with wide temperature and pH stabilities, but also high enantioselectivity in the synthesis of various cyanohydrins. These properties make it suitable as an industrial biocatalyst. Arthropods are likely to be valuable sources of potential biocatalysts for the next generation of industrial biotechnology.”
“There followed several papers on the biochemistry of HCN production and the production of other defensive compounds in these interesting animals,” they wrote. “After arriving at UC Davis, Sean began a long series of brilliant studies on the chemical mechanisms used by plants to fend off attack by insects and various pathogens. This work centered on resistance in tomatoes, and over the years he collaborated with numerous students and colleagues. Studies analyzed the role of numerous chemicals produced by plants including tomatine, proteinase inhibitors, and various plant oxidative enzymes. Recent studies had included analyses of induced defenses and the interactions of chemicals with the biological agents such as parasitoids and baculoviruses used in various IPM and biological control programs.”
“A constant theme and frequently emphasized message in Sean's work was the fact that chemical-biological interactions were rarely simple and straightforward,” they wrote. “He stressed that in order to understand plant-insect interactions, for example, it was necessary to understand the interactions among plant chemicals, the overall characteristics of the insect's diet, the physiological state of the insect, and the modifiable characteristics of plant and insect. Chemical and biological context and chemical mixture were seen as critical determinants of biological activity; a simple view that natural products functioned merely as "toxins" or isolated defensive factors was often misleading.”
Carey, Dingle and Ullman praised Duffey's "truly interdisciplinary research that included several joint projects with members of the Entomology Department and also with colleagues in the departments of Nematology Ecology and Plant Pathology. We all experienced Sean insisting over and over that interactions are not simple and that one must understand the chemistry, the physiology, and the ecology to really understand interactions between plants, insects, and their pathogens. Sean's legacy is an outstanding record of how to go about studying plant-insect interactions, not just the gathering of data on interactions that occur.”
The legacy continues...
Teachers ask their students to make an insect collection. The project is considered a "rite of passage." However, often the students--whether they be middle school, high school or college level--don't know where to begin. Ditto for 4-H'ers enrolled in entomology projects.
What to do?
The UC Davis Department of Entomology and Nematology to the rescue. There, on the home page, students can access short, clear, concise videos on how to create an insect collection. They can watch and download them for free.
The story behind the story: Back in 2010, James R. Carey. professor of entomology, wanted to teach UC Davis students how to create and produce short videos that could tell the story in a minute or less. And he did just that.
The entire series, totaling 11 clips ranging in length from 32 seconds to 77 seconds, can be viewed in just less than 10 minutes.
“So in less than 10 minutes, someone can learn how to make an insect collection,” Carey says. The clips are tightly scripted, with an emphasis on brevity, simplicity and low cost.
The project continues to draw widespread interest and won an award from the Entomological Society of America. Carey, now a distinguished professor in the Department of Entomology and Nematology and active in research, teaching and public service, went on to win the ESA's 2015 national teaching award. It will be presented at the ESA's November meeting in Minnesota. The "How to Make an Insect Collection" project was just one of the many factors considered. (See his many other projects on his website.)
So, how do you make an insect collection? Easy!
Here are the videos:
Hand Collecting (32 seconds)
Using an Aspirator (34 seconds)
Ground Collecting (54 seconds)
Aquatic Collecting (58 seconds)
Using Nets (58 seconds)
Killing (51 seconds)
Pinning (43 seconds)
Point Mounting (50 seconds)
Labeling Specimens (48 seconds)
Spreading (77 seconds)
Storage and Display (32 seconds)
It's a sin to kill a mockingbird, wrote Pulitzer Prize-winning author Harper Lee in her classic novel, "To Kill a Mockingbird."
"Mockingbirds don't do one thing except make music for us to enjoy," one of her characters, Miss Maudie, wisely observed. "They don't eat up people's gardens, don't nest in corn cribs, they don't do one thing but sing their hearts out for us. That's why it's a sin to kill a mockingbird."
Harper Lee's work came to mind yesterday when we saw a praying mantis devouring a monarch butterfly on our butterfly bush, located next to several milkweed plants. We watched the clipped monarch wings flutter down and land among the leaves.
It was a female monarch. She may have stopped to sip some nectar during her egg-laying mission. The hungry predator ambushed her.
The shock of seeing a delicate monarch gripped between spiked forelegs stuns you, especially when you've just reared two monarchs and have two more to go.
"Umm, do you mind?" we wanted to ask the mantis. "Please eat the cabbage white butterflies, stink bugs and aphids, not the monarchs."
Praying mantids are considered beneficial insects, but all we've seen them eat are honey bees, sunflower bees, butterflies and an occasional Gulf Fritillary caterpillar. However, they do eat ants, wasps, flies, and moths, as well. The larger praying mantids prey on hummingbirds.
The Xerces Society for Invertebrate Conservation summed up the monarch decline well on its website: "Monarch butterflies (Danaus plexippus) of North America are renowned for their long-distance seasonal migration and spectacular winter gatherings in Mexico and California. The monarch butterfly population has recently declined to dangerously low levels. In the 1990s, estimates of up to one billion monarchs made the epic flight each fall from the northern plains of the U.S. and Canada to sites in the oyamel fir forests north of Mexico City, and more than one million monarchs overwintered in forested groves on the California Coast. Now, researchers and citizen scientists estimate that only about 56.5 million monarchs remain, representing a decline of more than 80% from the 21 year average across North America."
Okay, praying mantis. We know. It was only one. You have to eat, too. You needed the protein to lay your ootheca. But have you ever considered how tasty and prevalent cabbage white butterflies are?