Tag Archives: European Honey Bee

Bees and “Wannabees”: Native Pollinators Tend Early Summer Blooms

European Honey Bee on Goldenrod, summer of 2015

When most of us think of pollinators, the European Honey Bee (Apis mellifera) comes to mind first – and with good reason. These hive bees work industriously in agricultural fields and orchards. And we benefit from the fruits, vegetables and of course flowers they visit.  According to MSU Extension, though, they are active in temperatures above 60 °F and prefer clear, sunny, placid weather. In case you haven’t noticed (or don’t live in Michigan), that’s not yet our weather here this year.

Luckily, native bees and hoverflies come to our rescue, and the rescue of countless wildflowers. Bumblebees (genus Bombus), our chunky native bees, only require temperatures above 50° and will fly in wet, dark and windy weather – the kind we’re living with this year! And along side them are other native bees and the ever-present hoverflies who look like bees but aren’t. So let’s see who’s out and about in our parks pollinating plants on these cool, damp days of early summer.

[A Disclaimer: I’m a learner when it comes to insect identification, but I’ve done my best to figure out what I’m seeing. Let me know in comments if you think I’ve erred. And if you’d like more detailed info, check out my two main sources: a fine book by Heather Holm entitled Pollinators of Native Plants and this excellent web article by Jason Gibbs from MSU Dept. of Etymology.]

Native Bees Happily Take on the Job of Spring Pollination

Female bees of all species carry most of the load when it comes to pollination, because they feed pollen to themselves and their young. Some species stash it on hairs or in pollen baskets on their hind legs. Others let it spread thickly across the stiff hairs of their abdomen. Wasps, like Yellow Jackets or Hornets, can look like bees but they don’t collect or eat pollen. (They are predators who keep insect numbers in check, including some garden pests.) So if you see lots of yellow or orange pollen on the leg or abdomen of an insect, it’s a bee! Where are these bees finding pollen now?

Native Wild Lupine (Lupine perennis) rises elegantly within the restored prairie at Charles Ilsley Park in early June. Look for them near the observation deck at Gallagher Creek Park as well. They are a popular stop on the pollen route for our native bees right now.

Lupines at Charles Ilsley Park where prairies are being restored

A Metallic Green Sweat Bee (genus Agapostemon) found the Lupine blossoms irresistible. These very small bees are solitary; they don’t live in hives. Instead, they make tunnels in bare soil and tend their young alone. Sweat bees are occasionally attracted to human sweat on hot, dry days but their sting is not as severe as a bee or wasp. They are normally docile while foraging but can be aggressive if you get near their nests. But please don’t use pesticides on them. These little bees do a lot of pollinating! Creating a spot of bare soil on your property away from your garden and house where they can nest will make both you and them feel safer.

A metalic green sweat bee finds its way into a lupine blossom.

One cool afternoon, I watched a couple of sweat bees make the proverbial “beeline”  for the native Daisy Fleabane (Erigeron annuus), a close relative of asters and daisies, but a different genus. These tiny, sun-faced flowers are one of the first blooms to emerge in spring and they last all summer. So it seems that the two sweat bees heading in from the right on the photo below know a reliable source of nectar and pollen when they see one!

Two metallic green sweat bees heading for a tiny Daisy Fleabane.

A native Bumblebee (genus Bombus) used its long tongue to reach inside the lavender lips of the Lupine blossoms at Gallagher Creek Park and then flew off with its pollen load tucked neatly into the pollen sacks on its legs. According to author Heather Holm, bumblebees sometimes use a technique called “buzz pollination” in which they release pollen from tight places by clinging onto a plant’s anthers (the tip of the male stamen that holds the pollen) and activating their flight muscles, making a buzz. Poof! Out comes the pollen. Neat trick. (Click on photos to enlarge; hover cursor for captions.)

 

Carpenter Bees (genus Xylocopa) shape their nests by patiently shaving off wood bit by bit to make perfectly round holes, usually on the underside of branches, or at our house, under deck railings! They lay their eggs inside, sealing each egg in separately with neat plugs of pollen to keep the young larvae fed. Later, the young bees will overwinter in these nests to emerge for mating the following spring. Here’s what I’m quite sure is an Eastern Carpenter Bee (Xylocopa virginica) nuzzling a Blackberry blossom (Rubus allegheniensis). It looks a lot like a native Bumblebee, but its abdomen is shiny black instead of fuzzy and it has a dot in the center of its yellow thorax.

A Carpenter Bee collects pollen or nectar from a blackberry blossom.

The blackberry bush also hosted another bee. I believe it’s a Masked/Cellophane Bee (genus Hylaeus).  These solitary bees are the only ones that transport pollen in a crop like some birds do with seed.  These bees use exisiting cavities in wood for nesting, and wrap their larvae in a thin membrane that evidently gave them the name “cellophane bees” – and they also have white patches on their heads, hence the “masked” name.

A masked/cellophane bee carries pollen in its crop.

Native Golden Alexanders (Zizia aurea), an early summer flower, attracted the attention of another native pollinator, the solitary Leafcutter Bee (genus Megachilidae). They can be very active within blossoms, making what some sources describe as a “swimming motion.” Evidently, that also releases  a lot of pollen that they carry on stiff hairs on their abdomen. Their nests are built vertically in hollow plant stems or other natural cavities. They neatly cut and then chew bits of leaves to line each cell. Entomologists suppose that the leaves may preserve the moisture in the pollen plug at the end of each cell, so it will last until the larvae hatches to eat it. The larvae then pupates, emerges for a short life of a few weeks and starts the cycle again.

A Leafcutter Bee searches for both nectar and pollen on a Golden Alexanders blossom

And then there are the “Wannabees”

I love Jason Gibb’s term “wannabees” for the ubiquitous Hoverflies – also called flower flies – members of the genus Taxomerus (family Syrphidae).  Hoverflies visit flowers frequently and are commonly mistaken for bees. Many of them mimic bees and wasps, being patterned in white, black and  yellow (or orange). But they differ from bees in one important way; hoverflies do not have stingers. They just want their predators to think they do! They feed on both pollen and nectar. Though hoverflies don’t carry as much pollen on their smooth bodies as bees do on their fuzzy ones, they may make up for that by visiting flowers more often. As a result, they are considered the second most effective plant pollinators. Another great benefit of hoverflies is that their larvae eat aphids like crazy, much like ladybugs do. So they can keep plants healthy as well as do some pollinating.

Drama Unfolds on Daisy Fleabanes!

It’s not a surprise that the nodding stalks of Daisy Fleabane (Erigeron annuus) show up in every field in the spring. Hoverflies move constantly from one to the next since not many different wildflowers bloom in this cold spring! As they land, of course, they drop pollen on the waiting stigmas of the flower, just what’s needed to produce more Daisy Fleabane. From my observation, the flowers in bright sunlight get more attention from hoverflies than those in the shade. Perhaps they see in ultraviolet like bees and the flowers look much more inviting in the sunshine?

But more than just pollination is taking place on those sunny little blooms! It turns out that a Daisy Fleabane can be a stage for high drama – birth and death among the petals! One tiny fleabane flower featured the mating of two hoverflies while a third ignored them in its avid search for a good meal. The dispassionate female seems to be casually having a snack as well.

Two hoverflies mated on a Daisy Fleabane while one ignored them in the interest of finding nectar or pollen

And on another Fleabane blossom, an ambush!  I’ve just learned about Crab Spiders (genus Thomisidae). These crafty arachnids don’t spin webs. They simply sit on or just under the edges of flowers waiting to grab unwary insects. Those long curved front legs do look a bit crab-like!

A crab spider sitting on a fleabane blossom hoping, no doubt, to snag a careless insect.

The Bluebottle Fly (genus Calliphora) in the photo below seems to have been oblivious to a crab spider until it was grabbed around the middle by one of the long legs of its hidden predator. Those big fly eyes look vaguely shocked, don’t they? The hoverfly on the blossom above  seems unconcerned, its head deep in the pollen. And what I think is the green sweatbee flying in may choose to do the same on a different bloom. I doubt they stayed around long enough to be a second and third meal for the spider!

A crab spider under the edge of a fleabane has grabbed a fly for lunch, while an uninterested hoverfly eats nearby. And what I think is  another green sweat bee speeds in on the right.

What about the Butterflies?

Well, butterflies are arriving, or hatching or coming out from under bark after overwintering. But not many are present yet. And let’s face it; the flowers available now are not especially tempting when compared to the variety and plentitude of summer. So the butterflies that appear in the parks make do with other food sources – sweet tree sap, rotting fruits from last fall, carrion, even occasionally the nutrition left in animal scat! Here’s  a selection of the butterflies I’ve seen so far and not one of them was pollinating a flower! (Click on photos to enlarge; use pause button for captions.)

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I’ve also seen three different Monarchs but they didn’t stop to have photos taken. And the very tiny White-striped Black moth (Trichodezia albovittata) is a first sighting ever for me. Its miniscule black and white wings flutter so fast that when flying, it looks like a blurry signal of dots and dashes! I was so happy when it paused for a few moments!

Native Plants + Native Insects = Caterpillars + More Well-fed Bird Hatchlings

Two-day-old Eastern Bluebird hatchlings (Sialis sialis)

You’ve probably noticed that I’ve used the word “larvae” several times in this piece. The common term for these squiggly young is “caterpillar.” Caterpillars (as I’ve mentioned before) are the preferred food that birds stuff down the tender throats of their hatchlings. They are great baby food for birds, full of protein and fat and easy to swallow.

So let’s be glad that our native insects are out gathering pollen for two reasons. Our bees and wannabees keep the wildflowers (and eventually fruits and vegetables) reproducing year after year. But by also feeding pollen to all those larval bees and flies, they feed the young of clever birds who winkle them out of holes and pluck them off of leaves and limbs. Yes, we may get a few cut, chewed or even defoliated leaves in our garden. But many of those caterpillars will nourish the next generation of glorious birds singing the morning chorus! Now doesn’t that make you appreciate insects just a wee bit more?

Stewardship Manager Dr. Ben VanderWeide and volunteer Stephanie Patil with hundreds of native plants purchased by township residents through the Parks and Recreation Commission.

 

 

 

THIS WEEK AT BEAR CREEK: A Chickadee’s “Bed,” plus Insects Alive in Our Wintry World

insect tunnels on tree branch
The filigree of bark beetles on a fallen tree
Cam in red winter coat BC
Blog post and photos by Cam Mannino

During this cold week, when nature seemed pretty hunkered down – and I sure was! – I decided to explore how our local bugs get through the winter.  I’d always thought of insects as killed off by the cold – and many are – but others are biding their time and getting through the winter in surprising ways – like the bark beetle larvae which left their filigree in the fallen tree above.

A Chickadee’s Home for the Night?

But I did venture out at dusk to see if I could spot birds settling in for the night.  And a couple of Black-Capped Chickadees (Poecile atricapillus) obliged by disappearing into a snag.  One let its tail protrude from the hole long enough for me to locate it once it suddenly disappeared!

A closer look at the chickadee's tail coming out of its night-time hole
A chickadee’s tail protrudes from its night-time hole

When I tried lightening this hole on the computer, the little bird appeared to have turned its head straight upward to fit into the hole!  If that’s what really happened, I hope it found a more comfortable place to spend the night once I left. Perhaps just getting out of the cold, though,  is more important than a stiff neck.

Chickadee in hole for the night.jpg
The closest shot I managed to get of the chickadee in its hole for the night.

Now, Concerning the Winter Survival Strategies of Insects…

Bernd Heinrich, in his book, Winter World: The Ingenuity of Animal Survival,  claims“…there is no life-form on earth as diverse, varied, tough, and inventive as the insects. ”   Heinrich’s adjectives – diverse, tough, and inventive – certainly apply to the varied and creative strategies that our Bear Creek insects employ during the winter months!   So now,  while walking along the snowy trails, I can imagine all these small creatures swimming under the ice, tunneling beneath the bark, dozing in tree holes or eating inside plant galls, waiting like we all are, for the burgeoning of spring.

Wasps, Hornets, Bees and Ants:  Long Live the Queen!

This category of insect winter survival has two sub-strategies.  Almost all wasps, hornets and many bees, including our native Bumblebees (genus Bombus),  live only one season.  After mating in the fall, the only member of the hive that survives is the fertile queen.  She leaves  the hive and inserts herself into a crevice in a log or under bark – some moist place in which she won’t dry out as easily in the winter.  If she survives, she rouses in the spring and goes off to find a new nest location, lays eggs and the hive begins again (click on photos to enlarge or hover over them for captions).

European Honey Bees (Apis mellifera)and Ants (family Formiciadae) have a different strategy – staying in the hive with the queen, and protecting her during the winter. Honey Bees eat honey during the winter and they keep their hive and the queen warm by fanning their wings. They were imported from Europe because this survival strategy meant that Honey Bees dependably provided honey and crop fertilization from the same hive year after year.

Ants lower their metabolism in the winter and pile onto their queen in order to keep her warm. I believe I saw evidence of Carpenter Ants (genus Camponotus) in this tree on the western trail through our Oak/Hickory forest last summer and fall.

Carpenter ants
Possible evidence of Carpenter Ants who chew wood to create galleries between areas of their nest and then deposit it outside.

Carpenter Ants don’t eat wood like termites; they chew it to make the galleries that connect parts of their nest, and then deposit it outside. Assuming that these were Carpenter Ants, they will have moved deeper into the nest and are now hibernating together with their queen.

When spring warms a bee hive or an ant nest, bees and ants are ready to go, having survived the winter as adult insects.

Green Darners: Migration

A very small number of  insects migrate much as birds do. Those of you who read the blog this summer will remember that some of the Green Darners (Anax junius) head south in the winter.

Green Darner3
Some Green Darners, large dragonflies, migrate south in the winter and their offspring return in the spring.

According to National Geographic, these large dragonflies build up fat reserves and as cold weather sets in, some of them ride south on a north wind. Like avian migrants, they make stopovers to rest and feed along the way and, strangely, follow  the same flight paths as birds (don’t they worry about being eaten?). But unlike birds, it’s a one-way ticket for these Green Darners. They breed in the south and die and it’s their offspring that arrive the following spring.  Some Green Darners and many other dragonflies, though, use the following strategy.

Damselflies and Most Dragonflies:  Naiads under the Ice

Naiads appear in Greek mythology and children’s books (like C.S. Lewis’ The Chronicles of Narnia) as glamorous winged water nymphs overseeing streams, rivers, and fountains. The naiads under the ice at Bear Creek, however, are simply the homely immature life stage of the beautiful dragonflies and damselflies we see in the summer. In warm weather,  the females lay their eggs on vegetation  in the pond or marsh. Drab, wingless naiads with hooked jaws  hatch from the eggs.  Even in winter, these hungry carnivores are swimming about consuming mosquito larvae and other invertebrates.  After molting up to 15 times (some dragonflies take 3 years to finish molting!), they crawl up out of the water onto a plant, bend backwards out of their exoskeleton in one last molt and emerge in the warm sunshine as brightly colored and patterned dragonflies or damselflies like these:

A Quick Overview Before We Go On:  The rest of the insects I’m exploring here have a four stage development: 1) Fertile females produce eggs; 2) Larvae , which in butterflies and moths are also called caterpillars, emerge from the eggs and eat like crazy; 3) Pupae form. In butterflies, their bodies harden into their pupal form which  is called a chrysalis. Moths and many other insects spin cocoons and go through the pupal stage inside them; 4) Adults emerge from chrysalises or cocoons and mate to start the cycle again.  It turns out that different insects spend the winter alive and well –  but in different stages of development.

Overwintering as Adult Insects:  Mourning Cloak Butterflies

The adult Mourning Cloaks (Nymphalis antiopa) that we see in early spring emerge from bark crevices or trees holes where they hibernated during the winter (those woodpecker holes in snags do a lot of good, don’t they?).

mourning cloak (1)
Mourning Cloaks hibernate in tree holes so they can emerge in early spring to mate.

These early spring butterflies hatched the previous summer. They ate a little and then went into summer torpor, which is called “estivating.” In the fall, the adult butterflies became active again, ate to put on weight,  and settled into a hole to wait out the winter. In the spring, they emerge very early, sometimes when snow is still on the ground, and mate. And their eggs, larvae and pupae  begin the cycle again.

Overwintering as adults gives some butterflies an advantage since in early spring, there is less competition for food (tree sap, decaying matter) and fewer predators, since many birds haven’t yet returned from migration.

Overwintering as Pupae:  Spring Azure Butterflies

According to the University of Wisconsin Madison Field Station website, the tiny lavender/blue Spring Azure butterfly (Celastrina ladon) overwinters in the pupal stage that in butterflies is called a chrysalis. When the female emerges in early spring, she mates within hours of hatching, lays her eggs the next day and dies on the third – an extremely short adult life!

The Spring Azure overwinters, hatches, mates, lays egss and dies in three days!
The Spring Azure overwinters as a pupa.When the adult female butterfly emerges, it mates, lays eggs and dies in three days!

Larvae hatch from the eggs and eat for about a month. Each then forms a pupa (called a chrysalis in butterflies) and the Spring Azure stays in that form from early summer until the following spring! A long wait as a pupa for a very short time as adult mating butterfly!

Overwintering as Larvae (commonly called caterpillars): Bark Beetles and Woolly Bears

This overwintering strategy, like the Queen strategy of bees and ants,  takes at least a couple of forms – staying under bark or freezing solid!

Bark Beetles:  Busy Tunneling Under the Bark

Bark Beetles (family Curculionidae) are tiny insects (about 1/10 of an inch) that can survive the winter as larvae, pupae or adults. They are a major food source for woodpeckers, especially in the winter (so that’s why woodpeckers continuously peck at tree bark!). According to Donald Stokes’ book, Nature in Winter, adult insects bore through the bark to a softer inner layer. The males enlarge a “nuptial chamber” where mating takes place. The females then tunnel out into a branch or the trunk, under the bark, to lay their eggs. The larvae who hatch from the eggs make increasingly larger tunnels as they eat and grow during the winter.

Eventually, they form pupae under the bark from which adults emerge in the spring.  The adults  bore back through the bark and fly off to another tree. According to Wikipedia, some of these tiny insects become pests and kill trees, especially when climate change and other factors promote their survival.  Most, however, tunnel within weak and dying trees or aid in recycling the wood of dead trees.

Woolly Bear Caterpillars:  Freezing Solid!

Woolly Bear Caterpillars are the larval stage of the somewhat drab  Isabella Tiger Moth (Pyrrharctia isabella). These caterpillars, by the way,  don’t predict winter by their bands; they simply molt throughout the summer “becoming less black and more reddish as …winter approaches” (Bernd Heinrich, Winter World).  

Wooly bear
Woolly Bear Caterpillars freeze solid during the winter by supercooling and producing glucose, which works like anti-freeze, and then thaw in the spring to continue their life cycle.

In the fall, they curl up under leaf litter and survive the cold by a combination of supercooling (lowering their body temperature, even below 32 F!) and producing the glucose which functions as anti-freeze – just  like the spring frogs in a previous blog. They can even survive thawing and re-freezing throughout the winter! Their pupae can’t survive the cold, so they wait until late in March before thawing and beginning to spin their cocoons. Continue reading THIS WEEK AT BEAR CREEK: A Chickadee’s “Bed,” plus Insects Alive in Our Wintry World