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Brown-belted Bumble Bee, Bombus griseocollis, on Echinacea.
Photo by Kent McFarland of the Vermont Center for Ecostudies | |
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Almost everyone knows
that The Bees Are Dying. Colony Collapse Disorder has become a
recognizable phrase in lunch room conversations. But for most people, then, there
is a pause... what bees, exactly, are dying? Um, honey bees, of
course, isn't that right? The ones that pollinate all our food crops?
The causes for
pollinator decline are complex and not fully understood. But perhaps
the biggest concern is what we humans are doing. The
first thing that probably pops into your mind is pesticides, then
perhaps environmental degradation, habitat loss and climate change.
All those things are having an effect on the bees. But the most
devious devil in the works may be one that has been around for about
ten thousand years: domestication. Humans started messing with the
bees, as we have messed with so many other life forms, and things
started going downhill. Most worrisome of all, we don't seem to have
learned from our former mistakes with other animal species.
Honey bees are an
introduced species in North America. Most are living in managed hives
and being bred by humans. Now we have started breeding and managing
native species as well... mason bees, leafcutter bees, alkali bees,
and most notably bumble bees. Bumble bee populations are now also
declining - what a shocker.
Breeding and managing
our bees has resulted in a loss of genetic diversity, a loss of wild
vitality and stamina, and a decrease in disease resistance. It has
transferred diseases and parasites to our wild populations and
diluted their gene lines. The practice of using migratory bee hives
has increased disease through overcrowding, has promoted the rapid
spread of disease throughout the U.S., and encourages and supports
monoculture.
Every spring, over half
(60%) of all the managed honey bee hives in the country are loaded on
trucks and converge
upon California's almond groves. They come from as far away as New England. For two weeks 1.5 million hives of
bees work at pollinating over 750,000 acres of almonds. It is the
world's largest pollination event. When it's over, the bees are packed up and
taken away. There is nothing else growing in the almond groves. But
there are other monoculture fields... of alfalfa, clover, melons,
apples... where the bees are taken for another week or two. They travel around the country, following the crop bloom. It's a
fragile system where if anything goes wrong, if for any reason we
cannot transport vast numbers of honey bees to our crops at the
precise time of bloom, there is no backup. There are no wild bees
living in our huge monoculture fields because there is no food source
for them for most of the year.
When varroa mites
appeared (also an introduced species) beekeepers started applying
pesticide to kill the mites. The pesticide produced negative effects
on the bees and crept into the honey. It also did something more
insidious: it prevented the bees from co-evolving with and adapting
to the mites. In fact, it created super-mites that are resistant to
pesticides, much as antibiotics create super-resistant bacteria. It's
the same age-old story – humans try to manage something, screw it
up, then attempt to fix it and instead further screw it up.
Apparently, we cannot be taught.
Some people feel it's
questionable whether honey bees could now even survive without human
assistance.
Most of the major
staple crops for global human diets – wheat, corn, rice, barley,
millet, rye, sorghum – actually do not depend upon any animal
pollinators, bees or otherwise. They are in the grass family and as
such are self-pollinating or wind pollinated. These crops together
account for most of the world's food supply by weight and caloric
content (FAO, 2005). However fruits and vegetables provide essential
nutrients as well as diversity for human diets, and these crops DO rely
heavily on animal pollinators. For example, seven out of nine of our
major food sources of Vitamin C are animal pollinated: oranges,
tangerines, bell peppers, tomatoes, cabbage, melon and watermelon.
Melons, cucurbit squashes, almonds and most pome fruits (apples,
pears) are completely dependent on pollinators. And animal-pollinated
crops in general have a greater economic value, providing farmers
with more income per unit of land. Some of our oilseed crops depend
on pollinators too; and the forage and hay crops (clover, alfalfa)
used to feed livestock need pollination in order to produce seed.
Despite their critical
role, there is shockingly little known about pollinators, and nowhere
less than in the U.S. We have essentially no long-term data on
population trends, in contrast with the U.K. and Europe where much
better records show clear indications of declines. But collectively,
the evidence we do have indicates that many American pollinators are
in decline.
SO DON'T JUST SIT
THERE, DO SOMETHING. HERE'S HOW.
CONSERVATION ACTION
STEPS
Regulate and eliminate
use of chemicals
Kent McFarland, senior
conservation biologist at the Vermont Center for Ecostudies in
Norwich, Vermont, points out that recent research fingers pesticides as
harming bee populations. Neonicotinoids, introduced in the 1990s, are
one of the most widely used crop pesticides in the world. They affect
bees' nervous systems and behavior, including homing instincts and
the ability to gather food. Without enough food the queens don't
reproduce as much and colonies become smaller and produce fewer
queens. There is also evidence that low levels of these pesticides
reduce the bees' levels of resistance to fungal infections (US
Agriculture Department's Bee Research Laboratory). Neonicotinoids
have been banned in France, Italy and Germany; beekeepers in the U.S.
and Great Britain are calling for similar bans.
Bees have low fecundity
– they do not reproduce rapidly or in large numbers. So they are
slow to recover from population depletion, no matter what the cause.
For example, bumble bee populations were found to take 3 to 4 years
to rebound after pesticide application (Plowright et al, 1978).
WHAT YOU CAN DO: Lobby
to ban neonicotinoids as well as other pesticides and don't use them
at home. Be an organic localvore. Write to law makers and farmers.
Most of all, help raise awareness, and encourage everyone to let our
wallets do the talking – just buy foods that are grown without
these pesticides. Just do it!
Avoid GE Crops
While studies have
indicated that contamination from GE crops can have “negative
effects” on bees, there is allegedly no documentation linking GE
crops with actual bee population decline. However, every stress
factor contributes to weakening the health and resistance of bees and
other pollinators. The negative effects of GE crops is just one more
thing for them to have to deal with on top of everything else.
WHAT YOU CAN DO: Just
don't buy GE foods. Help raise more awareness of GE oils and
livestock feed. Many otherwise organic products still contain GE
oils; for example, most tortilla chips that are “made with organic
corn” still contain non-organic canola oil – almost certainly GE.
Many farms that raise grass-fed beef still “finish” their cows
with non-organic grain, again, almost certainly GE. Tell your farmers
you don't need your cows finished!
Clean up the air
Researchers at the
University of Virginia found that pollutants from cars and industry –
ozone, hydroxyl, nitrate radicals – bond with flower scent
molecules and keep them from traveling as far as they normally would.
This inhibits the ability of pollinators to find the fragrance and
the flowers. They must travel further and expend more energy to find
dinner – and fewer flowers get pollinated.
Stop feeding bees sugar
water?
It is common practice
to feed domestic bees with sugar water at certain times, such as in
early spring when honey reserves are low after the winter. While low
honey reserves can occur even for wild bees, it is obviously a
typical result of human harvesting of honey. Also, bumble bees used
for greenhouse tomato pollination must be fed since tomato blossoms
provide pollen but not nectar. Feeding solutions, typically provided
by the same company that sells the bees, contain sugar, preservatives
and artificial coloring (to make it easier for humans to see the
level of the solution). Cane sugar has typically been processed with various chemicals. Beekeepers are now being warned against feeding bees with high
fructose corn syrup; studies indicate that when warmed to temperatures that can occur in bee hives,
it produces a toxin, hydroxymethylfurfural (HMF), that kills honey bees. Could these artificial feeding solutions be lowering the bees' resistance to other
stress factors?
Conserve and replenish
habitat and forage
This is an area with
lots of opportunity for individuals to make a difference. In general,
pollinators need wild woodsy natural habitat with native plant
species, not spaces that are tidily managed by humans and dominated
by introduced plants. Studies show that it's not necessarily just
diversity that's important but more the actual composition of floral
species. Also, keep in mind that pollinators need more than just
food. They need resources for breeding, nesting, overwintering and
all the other aspects of their lives, just as you do.
Conservation of
existing habitat should be a priority since restored habitats might
not include everything necessary for pollinator survival; we just
don't know enough about their needs, and humans are just not as good
at this stuff as Mother Nature. Besides, it's physically and
politically much easier to preserve what's already there than to try
and re-create it.
***********************
MORE THINGS YOU CAN DO!
In your community:
* Advocate for your
local businesses, parks, golf courses, schools, and community areas
to become pollinator-friendly by landscaping with native plants and
allowing perimeters and islands to go natural.
* Support restoration
and especially preservation efforts for native habitats: prairie,
forests, wetlands, etc. - including green wildlife corridors.
* Become a citizen
scientist; contact your local environmental organizations and
universities for information on how you can participate in pollinator
monitoring efforts.
* Organize events and
efforts to raise public awareness of pollinators in your community,
library and school: film showings, speakers, display boards,
newsletters, articles for local papers, fairs and events, etc.
* Become informed on
the truth about forest conservation. Carbon trading is a false
solution, and clear cutting diverse native hardwood forests and
replacing them with pine plantings is no solution at all. It
eliminates acres of hardwood blossom forage as well as dead wood,
stumps and other nesting sites – and creates countless other
problems.
At home:
* Practice diverse
wildlife landscaping with native plants in your yard, rather than
monoculture lawns or non-native species
* Allow weeds!
* Leave brush piles,
dead stumps, dead wood, undergrowth, etc. around the perimeter of
your property to provide habitat and nesting areas for pollinators
and other wildlife. Native bee nesting sites typically include dead
wood, suitable soil, and abandoned rodent burrows – the majority of
native bees nest underground.
* Plant a diversity of
native flowering plants – at least 15 species – and aim to have
at least three species in bloom at any given time, spring through
fall. Include spring blooming trees. Bees are sort of like bears.
They need to stock up in fall for the coming winter, whether to build
up their energy reserves or store food, and when they first emerge in
spring they need a quick source of food to replenish depleted
supplies. So an abundance of spring and fall bloom is sure to make
your property a popular pollinator hangout.
* Choose perennials
over annuals; perennials provide more dependable annual food sources
and are usually richer in nectar than annuals.
* Use heirloom
varieties, which tend to have more fragrance, nectar and pollen.
* Avoid flowers bred as
“doubles” - double-flowered roses, marigolds, etc. They have been
bred for appearance and tend to have less nectar and pollen.
* Plant in clumps
* Choose a variety of
flower colors and shapes.
* Include
night-blooming plants for moths
* Provide water (a
birdbath, fountain, etc.) and a mud patch to serve as a mineral lick
for butterflies and a source of nest building material for bees. Add
a small amount of mineral salt or wood ash to the mud.
* Provide housing. Here
are some things you can try: create patches of bare ground within
perennial plantings such as hedgerows or pastures for ground nesters;
leave dead wood and standing snags; provide piles of stones; leave
clump-forming grasses; drill holes in dead wood; and put out nesting
boxes of various types such as drilled bee boards. Look on line for
information on nesting boxes for different bee species.
For farmers:
* Leave “insectary
strips” within fields or on field margins and buffer strips. These
provide pollen and nectar sources and attract pollinators.
* Use hedgerows.
* Plant cover crops
such as clover and buckwheat and allow them to bloom before tilling
them under. Plant native wildflower mixes in fallow or old fields or
allow the weeds to colonize them while the fields rest.
* Use drip or spray
irrigation instead of flooding, to avoid drowning ground-nesting
bees. Irrigate at night to avoid interfering with foraging and
nesting activity.
* Avoid extensive use
of plastic mulch.
* Try no-tillage
methods to avoid disturbing nest sites. The density of squash bees on
no-till farms is three times that of tilled farms (Shuler et al,
2005).
* Avoid pesticides.
Even products approved for organic gardening, such as pyrethrins and
rotenone, are toxic to pollinators. If they do not kill outright,
they can weaken pollinators, damage their nervous systems and affect
their reproduction. Native bees are smaller than honey bees so may be
harmed by smaller doses. If you must use a pesticide, avoid contact
with blooming plants, apply it in the late evening after bees stop
foraging, and use liquid, not powder.
