Here is an interesting article on Bees from the LA Times Nov 23.
Adrian Wenner, one of out Bee list participants is quoted in this article.
Enjoy reading. BTW Please excuse the format, I copied and pasted from the
WEB site.
Paul Cronshaw DC
Hobby Beekeeper in Santa Barbara,
******
What's the Buzz?
Honeybees, Vital Pollinators of Gardens and Crops,
Are Disappearing
By ROBERT SMAUS, Times Garden Editor
Big changes are awing in the world of bees.
A backyard gardener calls from
Burbank to ask a county agricultural
official where all the bees have gone.
Another wants to know why he no
longer gets many squash or
peppers in summer and why there are so few
apples on his tree.
Did you see many bees this summer?
One-third of the food on our table comes
to us thanks to the pollinating efforts
of the common, everyday honeybee, according to
Michael Pearson, Los Angeles
County's apiary inspector. But honeybees are
in trouble.
"It's a disaster, actually," said bee
scientist Adrian Wenner, a professor
emeritus at UC Santa Barbara.
The honeybee has been hit hard by two
predatory mites introduced by accident
in the late 1980s. The mites have decimated
feral hives. Efforts to protect managed
hives, coinciding with changes in tax laws,
have made it difficult to commercially
keep bees in those little white boxes that
used to dot the
landscape.
The result is drastically fewer bees.
Stephen Buchmann, researcher with the
Forgotten Pollinators Campaign, an Arizona
group that is promoting the unsung
native bees, says the nationwide population of
ordinary honeybees has shrunk from
about 5.9 million colonies in 1945 to 1.9
million today.
He and others hope that native bees will
replace honeybees as pollinators, and
there's a good chance they might, but native
bees are also in a fix: They are finding
homes hard to come by in Southern California's
dense neighborhoods.
More likely, Africanized bees--the
so-called killer bees--will take the place of
honeybees because they are more resistant to
the mites. The Africanized bees are in the
southeast corner of the state, having started
their northward trek after imported African
bees escaped from a Brazilian laboratory in 1957.
Honeybees become Africanized when the
queens mate with descendants of
these escapees. From then on, the progeny are
called Africanized. Honeybee colonies
are not booted out by new bees, they are
simply absorbed and converted by a new
hybrid queen.
Although they look very similar to
regular honeybees (they are slightly smaller),
they are much more aggressive, not liking
anyone--people, animals, even leaf
blowers--in their neighborhood.
The Advent of Africanized Bees
Although avid gardeners are quite
concerned about the disappearance of the
honeybee, the arrival of Africanized bees is
perhaps of more concern to the average
homeowner, especially to those who already
fear bees or have allergies. Calling them
killer bees--an unfair moniker given the
facts--hasn't helped.
It was predicted that they would be in
metropolitan Southern California in 1994,
but, according to Pearson, who is also the
county's Africanized bee expert, they're
temporarily stalled in about 10,000 square
miles of desert in Imperial County and
eastern San Diego and Riverside counties.
Extremely precise maps are being used to
track their progress, said Bob Donley
with the agricultural commissioner's office,
the county agency keeping track of
Africanized bees, and it is expected they'll
get here, sooner or later.
They have already overrun Tucson, where
15% of the wild bee population was
Africanized in 1994. The total reached 56% the
next year and 90% by 1996. Today,
virtually all the honeybees in Tucson are
Africanized, except those managed in hives
by beekeepers, who routinely check to make
sure the queen is not Africanized.
Although swarms of bees have been known
to sting a person as many as 1,000
times, it is rare, according to Steven
Thoenes, a former U.S. Department of
Agriculture bee scientist and owner of
BeeMaster Systems, a bee management
company in Tucson.
Since the Africanized bees came to town,
he said, "people's lifestyles really
haven't changed that much."
Although the bees must be respected, they
should not be feared. When
individuals are out foraging for pollen or
water, they are like any other honeybee,
docile unless pinched, swatted or stepped on.
Like ordinary honeybees, each can only
sting once, and the sting is no more
potent than the sting of an ordinary bee, but
when the colony becomes large, there are
plenty of angry bees to contend with if they
become riled.
Established colonies can kill, although
incidents are extremely rare. In this
country, five deaths are attributed to
Africanized bee stings since their arrival in
October 1990, two in Texas and three in Arizona.
There have been two incidents in
California, both involving tree-trimmers in the
Coachella area who ran from the bees; one was
stung 25 times before he made his
escape.
Africanized bees move, or swarm, more
often than ordinary honeybees and
people in Tucson are noticing more swarms in
their yards. There are about 5,000
swarms each year, according to Thoenes. His
company trapped and destroyed more
than 500 last April alone.
If promptly removed by professionals, the
bees are not a threat. When they are
swarming, they are not particularly
aggressive, but once they start building a new
hive, they become fiercely protective. Even
the vibrations and smells from leaf
blowers and power mowers (they cannot hear)
set them off.
Africanized bees can live in cavities of
just about any size, be they curbside
meter boxes, attics, even in empty flowerpots,
but they need to nest in the protection
of a cavity.
When they arrive in the Southland,
Pearson suggests, the way to keep them
away from your home is to eliminate cavities
of all kinds--"to really clean up the
yard"--and to cover openings in buildings with
1/8-inch or finer wire mesh.
Government agencies already have plans to
deal with them. County vector
control agencies will handle calls about
swarms, and emergency personal are being
trained to deal with stinging incidents.
Private pest control companies will do the
actual removing of swarms.
The key, Pearson said, will be to
report--and stay away from--any
"concentrated bee activity" that might suggest
a nearby hive. "Run the other way," he
suggested, and get inside a building or
vehicle. People can get away from Africanized
bees, which fly about 11-12 miles an hour but
only defend an area the size of a
football field, and then call pest control
companies to remove nests.
The Plight of the Honeybee
It is guessed that Africanized bees will
replace all of the feral honeybees in time.
These are the honeybees that live in the wild,
in trees or in walls of buildings and
probably visit your garden.
Although they might seem like natives,
honeybees were taken from Asia to
Europe ages ago, and then to the Americas in
the mid 17th century.
The mostly mild-mannered feral honeybees
have pollinated many home fruits
and vegetables through the years, all of the
stone fruits, apples and kiwi fruit, for
example, and such vegetables as eggplant,
peppers and squash. They are also
important pollinators of commercial crops.
Wenner, the retired professor, said they
are the "ultimate generalists" and
pollinate all sorts of blossoms, from alfalfa
to zucchini.
Even if these feral bees aren't converted
by Africanized bees, the wild colonies
have been decimated by mites in recent years
and could even become extinct (though
there have been some recent signs of recovery).
Two types of mites, one called the
vampire or varroa mite, introduced by
accident in 1988, and one called the tracheal,
introduced in 1984, are killing feral bees
by the bucketful.
The mites are also having an effect on
honeybees kept in commercial hives. The
destructive mites can be controlled with
special pest strips mounted between frames,
but that makes beekeeping more costly. In
addition, a subsidy given to bee keepers
was recently canceled, increasing costs and
reducing incentives.
Many of the bees formerly observed in
home gardens probably came from
commercial hives. Honeybees can travel several
miles and actively forage up to two
miles from the hive.
Pearson thinks that beekeeping should be
encouraged in towns where it is now
discouraged, to increase pollination. "Bees
and people can coexist," he said.
What About Native Bees?
There are many kinds of native bees;
about 500 species and sub-species live in
Southern California. Entomologist Robbin
Thorp, professor emeritus at UC Davis,
said at least 100 of these are common in and
around gardens in Southern California.
Shiny, solid black carpenter bees and
yellow-stripped bumblebees are the
biggest and best known of the native bees, but
there are many others.
Most, including sweat bees and alkali
bees, are solitary bees that do not make
colonies; they live in ground burrows. Some
live in deep, narrow cavities, like those
left by burrowing beetles, including the
leaf-cutter bees that make those fascinating
circular holes in rose leaves (used to cap
either end of their nests).
Casually observed, many look like flies
and most are somewhere between the
size of a house fly and a honeybee. Often they
are dull brown or gray in color. A few
have bright metallic, fly-like colors. Most of
the females can sting if provoked, though
they rarely do.
Some can be very helpful in the garden,
pollinating all sorts of fruiting crops.
Buchmann, the Arizona researcher, says that
native bees are better than honeybees at
pollinating some crops, including eggplant and
tomatoes.
Bumblebees are so good at pollinating
tomatoes, by a method known as "buzz
pollination," that they are being raised to
pollinate greenhouse tomatoes. When you
hear a high-pitched buzzing, they are shaking
pollen out of flowers with their wing
muscles. Bumblebees live in small colonies in
the ground.
The big, black, carpenter bees are also
good pollinators. Occasionally, a lucky
gardener will see one of the males, which are
dramatically covered with golden hairs.
They get their name by burrowing into
soft wood to make their nests. The
half-inch-wide holes look like they were
drilled with a precision power tool.
Squash, zucchini and pumpkins can be
pollinated by squash and gourd bees
that came north thousands of years ago along
with these crops from Mexico and
Central America. These ground-dwelling bees
rise very early, often before daybreak,
well before the flowers close at mid-morning.
Many native bees are early risers,
starting earlier in the season or on cloudy
days when no self-respecting honeybee ventures
out, one reason they make good
pollinators.
Will native bees take the place of the
dwindling honeybee? "They probably
will," said Robbin Thorp. "I certainly hope so.'
First they need places to live. In the
manicured city or suburban garden, this can
be hard to find.
Places Where Bees Can Make Homes
Thorp suggests leaving a little soil
uncultivated and bare--some moist, some
dry--where native bees can make homes. Retired
professor Wenner has left bare dirt
between the flagstones in his garden so he can
watch their burrowing activities; the
bare patches encourage the bees to stay in the
garden.
"Most native bees like the kind of place
people are always trying to get rid of,"
he said--bare ground, dead accumulated brush
and the like.
Thorp recommends keeping plenty of
flowers in bloom so they have a constant
pollen source and limiting the use of
pesticide sprays.
"People need to realize that every time
they get rid of some pest with sprays,
they also get rid of bees," he said. Bees are
very susceptible to many garden sprays.
It takes much longer, several years even,
for native bees to rebuild their
populations. Native bees reproduce slowly,
often producing young only once a year,
and the adults die before the young hatch.
With some kinds of leaf-cutting and mason
bees, you can try building bee
homes or shells that they can then build
inside. It's very simple: Take a chunk of 2x4
or 4x4 and drill holes, with the grain, four
to six inches deep. Several diameters of
holes work for different bees, according to
Thorp. The holes can be spaced rather
closely. Put the block of wood on the north
side of the house or under eaves, where it
is at least partly shaded. Various native bees
will line the drilled holes with leaves or
mud and move right in.
You can buy this kind of bee house, and
even bees to go in it. Entomo-Logic
(9807 N.E. 140th St., Bothell, WA 98011-5132,
[425] 820-8037) is one of several
small suppliers of bee homes and native bees.
The homes are pre-drilled blocks of
wood that you can hang in the garden. Each has
20 holes, and the holes are lined with
little cardboard tubes that can be removed for
cleaning. Cost is about $20.
You can also buy the tubes for $1 each,
filled with live mason bee larvae. They
are shipped in fall and winter and five to
seven bees come inside each tube, ready to
hatch. According to co-owner Kristina
Williams, mason bees are gentle, do not
swarm and sting only when swatted.
Mason bees are acknowledged orchard
pollinators, even doing their work when
ordinary honeybees are fast asleep on cloudy
days, one reason they've become
popular in the apple orchards of Washington
state. They also pollinate apples and
stone fruits (apricots, peaches and the like)
in California, even during wintry weather,
which is when blossoms often open.
Better crops on fruit trees this past
summer probably had something to do with
the sunny spring weather that encouraged early
bee activity.
* * *
Bees You Might See
Domesticated honeybees: They seem like
natives but were introduced from
Europe in the 17th century; they are kept in
hives by beekeepers.
Feral honeybees: Escaped from hives, they
live in the wild.
Africanized bees: They look like
honeybees but have mated with descendants of
escaped African bees.
Native bees: These have been here all
along and may be big, like a bumblebee,
or small, like a sweat bee.
1.) AFRICANIZED HONEYBEE
The buzz: No more harmful than the common
honeybee, their aggressiveness is
legendary. They are easily infuriated, and a
swarm will mass on a perceived danger,
delivering hundreds of stings. They are,
however, good pollinators.
The look: To the untrained eye,
Africanized honeybees look exactly like their
European cousins.
The sting: The same as a European's as
long as you are stung only once.
DISTANCE BEES WILL CHASE
European bees: Defend a distance of 350
to 450 yards.
Africanized bees: Defend up to half a mile.
TIME BEES TAKE TO ANGER
European bees: 19 seconds
Africanized bees: 3 seconds
OTHER COMMON BEES
2.) European Honeybee
The buzz: There are several strains of
this bee, all valued for their honey and
wax production and most of all for their
prodigious pollinating. Bees have been
domesti-cated since the dawn of agriculture
but also exist in the wild. A "true bee" of
the Apidae family.
The look: The familiar worker bee has a
fuzzy, deep gold striped abdomen.
The sting: Painful but harmless except to
sensitive people.
3.) Carpenter Bee
The buzz: This is a big bee of the
Anthophoridae family. Its name comes from
the tunnels it creates when building a nest,
and it's not picky about the kind of wood it
uses; even a telephone pole will do. Carpenter
bees are good pollinators, especially of
tomatoes.
The look: Up to an inch long, shiny dark
blue or black, and sometimes
mistaken for the more colorful bumblebee.
The sting: Female delivers a mild sting
and is slow to anger.
4.) Leaf-Cutter Bee
The buzz: Tiny member of the Megachilidae
family nests mostly in cavities. It
trims neat, circular holes in leaves and
carries the pulp back to line its nest. Leaf-cutter
bees are good general pollinators.
The look: Only a quarter- to-half-inch
long and quite hairy.
The sting: Won't attack, but females can
sting; their sting is less painful than a
honeybee's.
5.) Metallic Sweat Bee
The buzz: In the Halictidae family, the
house fly-sized bee nests in the ground.
Sweat bees are good general pollina-tors,
especially of melons.
The look: Just under a half- inch long,
with bright green, shiny bodies. Males
have striped abdomens.
The sting: If pinched or swatted, females
can sting, but the sting is less painful
than a honeybee's.
6.) Bumblebee
The buzz: Another "true bee," the
well-known giant of the garden nests in the
ground and feeds its young on pollen and
honey. Feared for its size and loud buzz.
Excellent pollinator of vegetables, especially
tomatoes.
The look: The four local species all have
variations on furry yellow and black
stripes and are up to an inch long.
The sting: Severe sting, but not easily
provoked.
BEE KILLERS
Varroa Mites
Female Actual size: 1.5 mm
Male Actual size: 1.3 mm
Where Mites Are Found
Varroa mites are found in or near bee
nests or eggs. Mites eat or infect bee
eggs.
Varroa mites are also found between the
ventral abdomi-nal segments of the bee
or on their backs.
Tracheal Mites
Tracheal mites are found in the airways
of the infected bees, causing the bees to
suffocate and die.
Honeybee actual sizes:
Worker bee
Drone
Queen bee
BEE BASICS
Compound eye
Simple eye
Head
Middle leg
Hind wing
Fore wing
Antenna
Pollen basket
Hind leg
Claw
Thorax
Abdomen
Stinger
Sources: California Department of Food
and Agriculture in San Diego, Los
Angeles County Agricultural
Commissioner/Weights and Measures; U.S. Department
of Agriculture; "Insects of the Los Angeles
Basin," by Charles Leonard Hogue; "A
Field Guide to the Insects," by Donald J.
Borror and Richard E. White, bumble bee
photo; Tony Rivetti, golden rod image; Wide
World photos, main bee; Pedro Iniguez,
Web sites
|
