Borrego Sun - Since 1949

Wildlife: Coexisting with Bees is A Matter of Life or Death

 

Last updated 9/14/2023 at 12:07pm

Native bumble bees are essential to the resilience of both agriculture and native ecosystems, and the loss of these and other native pollinators can have far ranging ecological consequences. Bumble Bees are now listed as endangered species.

Bees are disappearing at an alarming rate due to the excessive use of pesticides in crops and certain blood-sucking parasites that only reproduce in bee colonies. It's true that the extinction of bees would mean the end of humanity. If bees didn't exist, humans wouldn't either.

For many of us, bees are annoying. We think that their only purpose is to keep buzzing around and dropping their formic acid-laden stings on random people (this impression will certainly change when we stop getting spoonfuls of sweet honey in our morning cereal). The truth is, bees are crucial elements of our environment, and almost never get the credit that they deserve.

If bees didn't exist, humans wouldn't either.

Out of the 100 crop species that provide us with 90% of our food, 35% are pollinated by bees, birds and bats (source). It's that simple. Bees are the primary initiators of reproduction among plants, as they transfer pollen from the male stamens to the female pistils.

"Bees are under great threat from the combined effects of climate change, intensive agriculture, pesticides use, biodiversity loss and pollution."

Since 2006, the population of bees has declined considerably (source). Pesticides, disease, parasites, and poor weather due to global warming have played a major role in this worrying decline. Bee population has been on a decline in recent years. Some species were added to the endangered list in 2017 (seven species of Hawaiian yellow-faced bees) and 2018 (The rusty-patched bumblebee, Bombus affinis) so as to protect and revive their numbers. There have been a number of reasons for this decline.

Pesticides: Since the end of World War II, the use of pesticides in agriculture has increased exponentially. This intense use of pesticides, known as neonicotinoids (a relatively new class of insecticides that affect the central nervous system of insects, resulting in paralysis and death), has had a major role in the bees' decline (source). When bees are exposed to neonicotinoids, they go into a shock and forget their way home (sort of like the insect version of Alzheimer's).

Parasites: Along with pesticides, parasites known as Varrao mites (also called Varrao destructors) are also responsible for their death (source). The Varrao can only reproduce in a bee colony. They are blood-sucking parasites that affect adult and young bees equally. The disease inflicted by these mites can result in bees losing legs or wings, essentially killing them.

Colony Collapse Disorded: Beekeepers started reporting a sudden reduction in the number of bees. The adult bees disappeared suddenly and mostly together. The hives were left with just the queen and immature bees. Even the food was present in high quantities. In some cases, few adult bees were found attending to the queen. Reasons mentioned above are two of the many factors that play a role in this disorder.

Effects of Bee Extinction: Extinction of bees will affect plants, animals, availability of fuels, topography, clothing and of course, human life.

Effects on plants: Some plants are pollinated by wind, but that rate is very slow. Insects are the primary pollinators on the planet. Beetles and butterflies also pollinate, but bees are the most efficient insects for this purpose. Without bees, we wouldn't be able to savor delicious apples, cherries, and many other fruits and veggies (blueberries, avocado, broccoli, most leafy greens, cucumbers, pumpkins, and many more). Almond trees would be among the first casualties.

If bees went extinct, there would be a massive decline in the production of crops. Although crops like rice and wheat don't require insect pollination, can people survive by eating rice and bread all their life?

Effects on animals: Herbivores, who depend on certain plant species, will be affected first. They would go extinct if plants ceased to exist. For example, many cattle used for milk and meat depend on alfalfa and lupins, both of which depend on insect pollination. If the cow's food supply declines, then meat and milk production will decrease. This will seriously affect the human diet. Due to the declining population of herbivores, tertiary carnivores will begin to suffer immediately. The only beneficiaries from this scenario would be scavengers (eagles, vultures, ravens etc.)

Fuel: Canola, which is grown to use as both a fuel and cooking oil, depends highly on pollination. It is also used to produce biofuel. If we were to run out of biofuel, we'd have to rely on fossil fuels completely, thus putting further pressure on the environment.

Clothing: Cotton is very reliant on pollination. The disappearance of bees will lead to a huge setback in cotton production, as it will significantly reduce our choices in clothes (good luck enduring the humidity and heat of the desert while wearing nylon attire).

Topography: Since most plants would be unable to grow, grasslands would become barren and large-scale desertification will take place. Landslides would wipe out villages in one sweep. Ultimately, Earth will become one large plastic-laden, arid, dead planet.

Effects of Bee Extinction on Human Life: Less production of food crops will ultimately lead to worldwide famine. Hunger and poverty will be very common. Freshwater will start drying up as well as, as there will be less trees for water retention to occur. With less water and diminishing food, humans will die of thirst and starvation. Fertility would also suffer a setback, followed by a drop in the rate of reproduction. Ultimately, we wouldn't be able to sustain and would be forced into extinction within a few hundred years.

Unless scientists build robotic bees to do the jobs that honeybees once did, we're ultimately doomed. And although this isn't the most serious repercussion, we would never again taste that sweet, savory honey that we forcibly steal from honeybees every day.

The tragic irony of this is that by killing bees, we're only hurting ourselves. Our survival depends on the health of the planet and its species, and unless we begin to face this fact, we will continue to contribute to our own demise. Unless we take drastic measures to save the bees, the planet's survival is in doubt.

SAVING BUMBLE BEES: Like birds, bees lay eggs in nests. Some even "feather" their nests with plant material or the fluff from downy leaves. 70% of bees nest in tunnels in bare earth, 30% lay their eggs in cavities – holes in dead wood, hollow stems, or even cracks in concrete or stone (only honey bees form hives.) Both ground nesting and cavity nesting bees create a ball from pollen and nectar on which they deposit an egg in a "bee nursery" known as a brood chamber.

Ground nesting bees form tunnels in the ground with multiple brood chambers. Cavity nesting bees find an existing tunnel in the form of a hole in dead wood or the hollow stems of certain plants. They create brood chambers starting at the back of the tunnel and working their way to the front, sealing each chamber as they go with mud or bits of plant material.

Bumblebee species nest in small colonies where worker bees attend to the nest. They usually build their nest in dry, protected and hidden cavities below ground, such as an abandoned rodent burrow, under piles of wood or brush, under sheds or sometimes in old birdhouses.

When keeping a clean and tidy garden, we're frequently eliminating natural materials and features that would otherwise provide nesting habitat for bees and other insects. It may sound too good to be true – but here are some ways you can provide much needed habitat for bees and other insects while saving time, money, and energy.

Mulch less, mulch different: 70% of native bees nest in the ground. Frequently when the words "ground nesting" are mentioned, the natural reaction is to think of wasps, who have a bad reputation as ground nesting insects. Unlike ground nesting wasps, who will form hives in abandoned rodent burrows and larger underground cavities, native ground nesting bees form small, non-aggressive colonies.

Ground nesting bees, such as the mining bee are some of the earliest pollinators to emerge in spring, making them vital to pollination of fruit trees such as cherries, plums, and apricots, as well as other flowering trees, shrubs, and spring ephemerals. When it comes to ground nesting bees, access to bare ground is essential, and even a 1-inch layer of mulch can be as impenetrable as pavement to these small bees.

People mulch for many reasons; to suppress weeds, prevent erosion, and because they feel it provides a clean aesthetic. If you must mulch, consider using compost or shredded leaves instead of chipped wood products. These alternatives will have the same weed suppression, water retention, and other properties – yet be light enough to allow ground nesting bees to pass through.

Additionally, they release nutrients and provide organic matter that actually improves your soil quality! Also consider mulching just the parts you see. It's often sufficient to mulch just the first two feet or so into a bed, leaving areas in the back uncovered to allow access for pollinators.

Bees of the Andrena genus are commonly known as mining bees. They excavate tunnels in bare soil, such as this baseball field at an elementary school. They are non-aggressive and important early pollinators of many crops including fruit trees such as plums, peaches, and cherries.

Grow raspberries: and other plants with pithy or hollow stems such as Joe Pye weed (Eutrochium spp.), elderberry (Sambucus spp.), hydrangea, and others. Cavity nesting bees will make nests in the dried stems and twigs from previous years' growth, so don't aggressively cut back or clean up these plants and consider leaving dead branches alone. Other invasive plants such as bamboo, Japanese knotweed, and teasel should not be planted, but bundles of bamboo stems can serve as valuable nesting material.

Don't forget the grasses, too! While we often skip grasses for showy flowers, native bunch grasses, such as switchgrass (Panicum spp.), Indian grass (Sorghastrum nutans), prairie dropseed (Sporobolus heterolepsis), little bluestem (Schizachyrium scoparium), big bluestem (Andropogon geradii), and grama grass (Bouteloua spp.) provide nesting sites and protection for bumble bee queens to overwinter. Many of these grasses do double duty, serving as butterfly host plants as well.

Providing natural nesting materials is the best way to support native bees, and can bring benefits to a variety of other wildlife, too. Plants with pithy stems can be excavated by small carpenter bees and other cavity-nesters.

Save a (dead) tree or "plant" a log: Maybe it's a reminder of our own mortality, but when we see a dead tree or even a dead branch, o our first impulse is often "that's gotta go!" In many cases this material poses no real danger, and, if it can be tolerated, this dead woody material provides an abundance of habitat for all sorts of wildlife.

Beetles and carpenter ants burrow into dead wood, birds go after these insect treats, and this activity creates perfect chambers for cavity nesting bees to lay their eggs. While you may not want to gaze lovingly upon a dead tree from your kitchen window over morning coffee, you can add this valuable habitat to your landscape by leaving piles of twigs, branches, or logs in your garden.

Build a better brush pile: The very mention of a brush pile conjures up such nightmarish images (fire! snakes!) that the idea of adding one to your carefully cultivated landscape may seem anathema. Yet adding a brush pile is one of the most effective ways you can provide habitat for a diversity of wildlife while also benefiting the environment and saving money in the long-term.

In most municipalities, local waste management authorities will collect curbside brush and either chip it and compost it or haul it off to a landfill. In both cases, you're paying for this service in your trash bill. If everyone retained just a small amount of their clippings and pruned branches, we could reduce the burden on our waste management system.

More to the point however, small mammals will also make use of a brush pile, creating burrows that later provide space for bumble bees to nest. Brush piles also provide cover for other ground nesting bees, and provide food for many other invertebrates who eventually break the piles down into valuable organic matter for your garden.

A small brush pile in an out of view spot in your garden provides shelter and nesting opportunities for all manner of invertebrates, birds, amphibians, and other wildlife.

Worried about it being an eyesore? Get creative and build a "brush fence", hide the pile behind ornamental grasses, or simply install a Pollinator Friendly Habitat sign to advertise your good intentions to your neighbors.

In recent years the concept of "bee houses" have gained popularity, with many D.I.Y. versions popping up on Pinterest and commercially available versions appearing in gardening catalogs. These artificial nesting structures are meant to support mason bees, leafcutter bees, and other cavity nesters.

Bee houses: Some use cuts of bamboo, others cardboard tubes. Many are elaborate and quite beautiful – but the efficacy of these structures varies widely. Building a bee hotel can be fun, crafty, D.I.Y. adventure, and provide valuable nesting habitat, but when not properly maintained these structures become a sponge for pathogens and mites, which build up in the nesting material over time. If choosing to design and build or purchase a man-made bee hotel, just be aware it's not a "set it and forget it" proposition.

A small collection of bamboo stalks is an easy and inexpensive way to provide nesting habitat. Make a new nest over the winter each year and hang it next to the old one. Once the bees have emerged in spring, remove and discard the old material.

One of the easiest ways to create a "bee hotel" with minimal effort and maintenance is simply to bundle cuts of bamboo or other hollow or pithy stems that are closed at one end (bees will not lay eggs in cavities open at both sides) and hang them in a sheltered location. If possible, orient the material so it's facing southeast so it will be warmed by the morning sun. Bamboo and common reed both provide excellent material for this purpose.

Often you can cut just behind the node (raised bumpy part of the stem) to create a perfect tunnel. Hang your bundle beneath a roof overhang or other sheltered location or place them in a bucket laid on its side.

Whatever material you use, be sure to replace it every other year to destroy any pathogens or mites that may have also taken up residence in the material. A good plan is to make a new nest over the winter each year and hang it next to the old one. Once the bees have emerged in spring, remove and discard the old material.