Bohart Museum Societybohart.ucdavis.edu/uploads/5/6/2/5/56256413/58_2014...Bohart Museum Society Newsletter Spring 2014 CONTENTS Directors Note 1 Spotlight on a Species single nest

CONTENTS

Directors Note 1

Spotlight on a Species 1

Museum News 2

More Museum News 3

Golden Gate BioBlitz 5

Honey Bees and Cell Towers 6

The Bug Doctor 7

In This Issue

Bohart Museum Society

Spring 2014 Newsletter No. 58

SPOTLIGHT ON A SPECIES

Carpenter Bees By Lynn S. Kimsey

In the spring there are two distinctive groups of large bees, bumble bees (genus Bombus) and carpenter bees (genus Xylocopa). These are among the largest of the North American bees and are generally the earliest to emerge after winter. Carpenter bees are often confused with bumblebees but can easily be distinguished by being less hairy and with a shiny black or brown abdomen. Bumblebees are so hairy that the shininess of their exoskeleton isn't visible. They also have bands or patches of yellow, white and/or orange hair on their body.

Xylocopa is a large genus with nearly 500 species found on nearly all continents. We know them here in the U.S. mostly because of their large size and their habit of excavating nest tunnels into our fences, decks and other structural wood (see image on page 4). Females make nests by tunneling into soft wood with their powerful jaws, and building tunnels that they partition into individual cells, one cell for each larva. The partitions between the cells are made with a mixture of wood particles and saliva. The female places food in each cell, lays an egg on it and then seals the cell. She then moves on to the next cell and repeats the performance.

Carpenter bees are solitary nesters by nature, unlike bumblebees, but can be found nesting near each other in large numbers if the wood resource is large, such as tree trunks. They nest in structural wood, such as pine and redwood, but they will also build nests in dead trees or branches where the wood is hard enough to shape a clean tunnel, but not yet soft and pithy. The nests have a circular entrance hole that is a bit more than a half inch in diameter. Each nest has an entrance tunnel of varying lengths, with one or more lateral branches depending on the width of the wood. There can be up to 20 larval cells in a single nest tunnel. Females can evidently make multiple nests in a single season. Adult females only live a few months; males considerably less than that.

Young carpenter bees overwinter inside old nest tunnels and emerge in the spring. When they emerge they seek mates and the females then go on to build new nests.

Bohart Museum Society Newsletter Spring 2014

Male valley carpenter bee or teddy bear bee. Photo courtesy of Kathy Garvey.

Directors Note-

Spring is finally here and its finally raining, which means this is the perfect time to talk about flowers and bees. This issue of the newsletter covers both. We’ve also had lots of activities and events since the last newsletter, some of which are highlighted below.

I also felt it was important to acknowledge one of our most important volunteers, Jeff Smith.

Our apologies for confusion about renewing your society membership. The membership form for 2014 is included in this issue of the newsletter in case you haven’t renewed for the year.

-Lynn Kimsey Female valley carpenter bee. Photo courtesy of Kathy Garvey.

Continued on page 4.

2


MUSEUM NEWS

personally spread the wings of nearly 200,000 field pinned butterflies and moths in the collection;

donated more than 14,000 specimens from his own collection;

built more than 2,000 glass topped specimen drawers either from kits purchased by the museum or from scratch!;

recurated the major moth and butterfly families, including Nymphalidae, Noctuidae, Notodontidae, Torticidae, Ethmiidae and what used to be the tiger moths (Arctiidae);

donated more than 6,000 foam bottomed unit boxes, 5,000 pins, 7 reams of label paper;

and has made financial donations as well!

We really don’t know what we’d do without Jeff.

Jeff Smith is one of the more important members of the museum crew. Jeff began volunteering in the museum when we were still located in Briggs Hall in the mid 1990’s. Since then he’s been coming in once or twice a month to continue his work organizing, identifying and generally recurating the entire moth and butterfly collection. Since retiring he’s been spending even more time on the collection.

It has become Jeff’s personal mission to make this one of the best Lepidoptera collections in the U.S. (and to make it neat).

He also helps out in nearly all of our weekend open houses and outreach events like UC Davis’ Picnic Day, which occurs every April.

Its very difficult to completely detail all the contributions that Jeff has made to the museum over the past 20 years or so, but here’s a snap shot. He has:

One of the best known members of the museum petting zoo is Rosie, the rose haired tarantula. She was donated to the museum two years ago by Jeff Smith. At the time he had had her for more than 15 years. Best we can tell Rosie is nearly 23 years old; older than many of the students who work in the museum!

Since then she has become one of our best ambassadors to the world of insects (well OK bugs…). During Picnic Day , Rosie is held by hundreds of visitors. She is calm and has never once shown any thing more than patience.

Meet Rosie! Jeff Smith King of the Leps

Molly Dunning and Rosie enjoying a little quality time at the March 2014 museum open house. Photo by Kathy Garvey.

Lynn Kimsey and Jeff Smith holding one of the museum drawers made by Jeff from planks from her

redwood deck. Photo by Kathy Garvey.

3

MUSEUM NEWS


Surviving Picnic Day!

This year marked the 100th year of Picnic Day at UC Davis. The weather was fine and the crowds huge; the campus reported 75,000 visitors. The Bohart Museum had more than 4,000 visitors in a 6 hour

period. This is the largest number of visitors we’ve ever had. Everyone had a great time. Rosie the tarantula was a real trooper and was handled by more than 400 visitors!

Belize Project:

Establishing an Entomology Collection and Conducting a Bat

Inventory in Belize

David Wyatt at Sacramento City College and graduate student M. Fran Keller have begun a project to build an entomology collection in Belize. They established a crowd source site to fund the project (https://experiment.com/projects/cataloging-insect-and-bat-diversity-in-belize/updates).

Unfortunately, this newsletter is coming out too late for members to contribute to the site but additional support is welcome to cover the airfare of several participants, including Fran Keller.

Laurie Casebier, Megan Crawford and Jessica Gillung showing off members of the petting zoo. Photo by Alex Nguyen.

Leia Matern in the gift shop. Photo by Alex Nguyen.

Tom Zavortink and Nicole Tam showing off our petting zoo. Photo by Felipe Andreazza.

Jeff Smith and Rosie with a visitor. Photo by Alex Nguyen.

Hesperiid skipper butterfly discovered in Belize.

Photo by David Wyatt.

Jessica Gillung and a hissing

cockroach. Photo by Alex

Nguyen.

4


As with the majority of bees, carpenter bees feed their offspring a mixture of nectar and pollen; a sort of bee bread. They are important pollinators for some flowers but they have the bad habit of robbing tubular ones. Carpenter bees have stout, blade-like tongues and heavy jaws that they use to pierce the side wall of tubular flowers so they can collect the nectar without entering the flower. This is great for the bee but bad for the flower as the flower gets robbed but not pollinated.

There are two eastern species, the eastern (Xylocopa virginica) and southern (X. micans) carpenter bees, and three western species, the valley (X. varipuncta), foothill (X. tabaniformis) and the California (X. californica) carpenter bees. Each species is characterized by different body sizes and male coloration.

Female carpenter bees are all heavy bodied and shiny black. Females of the species differ primarily in size, metallic tints on the black body and the color of the wings. In the western species the males are distinctively colored. Male valley carpenter bees are often called teddy bear bees because they are fluffy, and yellowish brown, with green eyes. Males of the other two species more closely resemble females. Male foothill carpenter bees are shiny black with bright yellow hairs on the top of the

thorax. Male foothill carpenter bees are also shiny black but have pale, whitish hairs on the thorax and first abdominal segment.

Males have nothing to do with building nests. Once they emerge from the nest as adults they never return. Male carpenter bees find females in two different ways. Those with large eyes, such as male foothill carpenter bees, search for females by patrolling or hovering over flowering plants that females might visit. They will even fly at humans walking by, but there is no cause for concern since male bees cannot sting. The other strategy is seen in male valley carpenter bees. These males have relatively small heads and eyes but they have a large gland in the thorax that produce pheromones (think of it as cologne) to attract females as they fly around. They will try to drive away other males .

Carpenter bees have become a dominant part of the bee fauna in this part of California, perhaps due to the large number of aging redwood fences and decks. Whatever the reason for their abundance carpenter bees can be a problem, causing structural damage to anything built from these woods. Replacing damaged wood with new is

one approach. If the damage isn't too extensive the burrow entrances and tunnels can be filled with caulking compound. This will prevent females from reusing the previous year's nests. Also, they will not burrow into wood treated with preservatives, such as copper naphthenate, borates or creosote as examples. However, once the wood is sufficiently aged that the preservative is largely gone, carpenter bees may then enter the wood. As with other pests there are many ineffective repellents on the market. Really the best approach is to pay attention and fill the holes when you find them.

Aside from damaging wood, these bees pose little risk to anyone. Males cannot sting and females only sting if they are captured. The best way to get stung by a female carpenter bee is to catch one in an insect net and reach inside bare handed to put it in a kill jar…

For more information on carpenter bees go to the Bohart Museum website: http://bohart.ucdavis.edu/pdfs/CarpenterBees.pdf

and the UC IPM Online pestnotes:

http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7417.html.

Continued from page 1.

Carpenter bee tunnels in tree branch. Photo by Kathy Garvey.

Male teddy bear bee. Photo by Kathy Garvey.

5

GOLDEN GATE NATIONAL PARKS BIOBLITZ MARCH 28-29, 2014


In late March the UC Davis Entomology Club and museum staff, 30 in all, participated in the first Golden Gate National Parks BioBlitz. This event was sponsored by the U.S. National Park Service (NPS), National Geographic Society, Presidio Trust and the Golden Gate National Parks Conservancy.

A bioblitz is a 24 to 48 hour biological inventory of a park that involves volunteers, scientists and park employees. The term was originally coined by NPS naturalist Susan Rudy during the very first bioblitz in Washington, D.C.

The Golden Gate National Parks include more than 80,000 acres in national parks, recreation areas and historical sites between Point Reyes and Half Moon Bay, including Alcatraz Island.

The majority of our group camped at Kirby Beach on the north side of the Golden Gate. The rest stayed in a hostel on the Marin headlands. We helped out with public activities in 8 different sites across Marin, San Francisco and San Mateo counties.

The first official day of the event, Friday was gorgeous. Sunny, warm and clear. We worked with bus loads of

elementary age and high school students from local schools. The kids learned how to look for insects and how to collect them for further study.

Saturday was a different story. That night in the campground the wind started to howl and by the next morning it was pretty clear that a big storm was on its way.

In the morning several of our groups surveyed aquatic insects in local streams. This worked pretty well in the rain. Everyone else doing net collecting got pretty wet. The rain came down in buckets and we finally said good bye after lunch and returned to Davis .

Surprisingly, our sampling was remarkably productive. We collected more than 300 species of insects including a new county record of the stag beetle, Platycerus oregonensis.

We also came across odd plant growth. A pine tree at the back of a newly uncovered creek on the Presidio had an odd hair piece. No one could decide what it was—lichen, dead

plant or bird nest. Turns out the entire creek had been engulfed by a plant called mattress vine (Muehlbeckia complexa), a pest from New Zealand. It even grew over the trees. When park crews cleared the creek they removed all of the mattress vine they could reach except on the top of this tree.

So you learn something every day. We had many adventures and got to explore parts of these parks that no one gets to see. Despite the rain we had a great time.

Wesley Mulder, Marko Marrero and Christine Melvin collecting termites at Kirby Beach.

Aquatic insect sampling demo by Felipe Andreazza.

Pine tree with toupe, formed by dead Muehlbeckia vine.

6


Honey Bees and Cell Towers

By Eric Mussen

We continue to get questions about the effect of cell towers, radio waves, electromagnetic forces, and other manmade issues on honey bees. Eric Mussen our Extension Apiculturist wrote this response to a question about cell phones and queen deaths. For more about honey bees you can check out Eric’s Apiculture Newsletter:

http://entomology.ucdavis.edu/Faculty/Eric_C_Mussen/Apiculture_Newsletter/

***********

The question of the effects on honey bees of electromagnetic forces (EMFs) comes up often enough to warrant a response.

From a totally practical point of view, there are beekeepers who purposely place their colonies in the cleared right-of-ways beneath high tension power lines and around the bases of cell phone towers. The weeds are kept clear, so access is readily available, and fire is less of a concern. Obviously, if the bees were being negatively affected very badly, the hives would not be placed there.

The few studies that purport to demonstrate negative effects on bees where EMFs are higher, normally fail to understand what a “controlled

experiment” is. In a controlled experiment, the researchers try to keep every single parameter exactly the same, except for the one factor of interest. So, if you wish to show that a cell phone is detrimental to colonies, then all the hives have to have their colonies “equalized” so that they start in the same condition (preferably with sister queens mated in the same nuc yard), having the same: number of frames of bees; amount of brood; amount of food; same levels of parasites and diseases; etc. The hives should be moved far enough apart so that what happens in one set of hives does not impact the other set, but they should be foraging from the same sources (sharing the resources).

Then, the suspected cause is introduced into one set of hives or the hives are moved very close to the possible cause of trouble. If the cause is put into the hives (like functioning cell phones) then the other hives have to have non-functioning cell phones put in them. Since the odor of the batteries might make a difference, the non-functioning cell phones need to be filled with truly “dead” batteries. The experiment should be replicated at three different locations using the similar problem-causer. Over a period of time, the colonies must be monitored to determine if there are any

differences in the parameters of interest.

If the differences between treatments turn out to be enormous in all colonies of one set versus the other, then one replication may be all that is needed. If the differences are going to be quite minor, but consistent, the number of colonies in each group has to be quite

large – at least ten colonies per treatment. In this case, the colonies have to be REALLY similar at the start, so that the variation among the colonies in a set is not so large that it masks the effects of the study.

A statistical analysis will determine if there truly is a difference in the colonies at the time they are monitored.

Very few experiments, set up in this manner, have been conducted on EMFs.

Honey bee queen surrounded by workers. Photo by Kathy Garvey.

Cell tower disguised as a palm, aka “monopalm”. Photo by Gary Minnaert; courtesy of Wikimedia Commons.

7

ASK THE BUG DOCTOR If you have an insect question, need advice, want an identification of something you’ve found, or would like to see an article in the newsletter on a particular topic let us know. Email us at [email protected].

Spotted-wing Drosophila

Drosophila, or vinegar flies, are common annoyances in the home or anywhere else in the vicinity of ripe fruit. They are also the basis for our

understanding of modern genetics.

Unfortunately, Drosophila suzukii, the spotted-wing drosophila, a relative of our common species is a major fruit pest. This fly is native to southeast Asia and was unintentionally introduced into the U.S. sometime in the 1980’s. By the time anyone realized it was present and was going to be a serious pest it was well-established in most states.

In California the fly is a serious pest of cherries, blackberries, raspberries, blue berries and figs, among others.

These are small brown flies with red eyes, averaging 2-3 mm in length. Superficially they look like regular Drosophila. However, they have two distinctive features, the black spot on the tip of the male’s wings and the saw-like ovipositor of the female, which is hard to see without a microscope.

Spotted-wing drosophila females lay their eggs in fruit by using their ovipositor to slit the fruit’s skin. As they do this they introduce yeast into the fruit. The larvae develop in the fruit feeding primarily on the yeast developing in the rapidly spoiling fruit.

Here in Davis, no one gets edible fruit from their cherry trees or berries unless they spray them at the right time during fruit development.

When Cells Go Wrong

On occasion things go very, weirdly wrong during development in insects. Rarely, an odd looking valley carpenter bee like the one pictured below appears.

Insects are bilaterally symmetrical like us. During development in these bees they can end up with male cells on one side and female cells on the other, resulting in a bee that is half brown and half black. Its particularly obvious in these bees because the two sexes are


so distinctively colored. These odd looking individuals are confused, don’t fly very well and they are sterile.

This mix up occurs very early in development. If it happens when the embryo consists of fewer than 100 cells bilateral symmetry occurs, if after that then the gynandromorphy is a mosaic and not symmetrical. Mosaic gynandromorphs are mixed up, for example the left half of the head may female, the right front leg female and left hind leg female, with the rest of the insect male.

Carpet Beetle Season

Given the weird spring weather this year, carpet beetles are having a banner year. If you haven’t year put away your wool clothes, now’s the time. Carpet beetles

are small variegated, oval beetles. The larvae are small, hairy caterpillar-like insects that are occasionally confused with bedbugs. The adults disperse during the spring looking for mates and new food sources for their larvae.

Carpet beetle larvae feed on any kind of dry protein source. They particularly like wool, feathers, hair and dried skin. They also really like dead insects, which makes them a huge problem in insect collections. The larvae are also commonly found in kitchens.

The best way to control their damage is to clean and store wool clothing and anything else like that in sealed plastic bags or containers during the warm months after winter is finally finished.

Female ovipositor of Drosophila suzukii. Photo courtesy of UC IPM program.

Male Drosophila suzukii. Photo courtesy of Gevork Arakelian, UC Riverside.

Gynandromorph of the valley carpenter bee (male on the left, female on the right). Photo courtesy of Sue Gilley.

Variegated carpet beetle. Photo courtesy of Phillip J. Pellitteri.

mailto:[email protected]

8

Bohart Museum Society c/o Department of Entomology & Nematology University of California One Shields Ave. Davis, CA 95616

Bohart Museum Societybohart.ucdavis.edu/uploads/5/6/2/5/56256413/58_2014...Bohart Museum Society Newsletter Spring 2014 CONTENTS Directors Note 1 Spotlight on a Species single nest

Documents