THIS WEEK AT BEAR CREEK: Bird Antics, Goldenrod Duplexes and Squirrel “Dreys”

Vertical Silver Maple buds painting look (1)

Warm days begin to bring out Silver Maple buds

Cam in red winter coat BC

Blog Post and Photos by Cam Mannino

What a puzzling week, eh?  Was it spring or late winter?  The buds on the Silver Maple (Acer saccharinum) near the Center Pond seemed as confused as the rest of us.  They began to emerge as the sun warmed  the cold air.  I was concerned about the effect of icy nights later in the week.  Alas,  a twisted ankle meant I couldn’t get back to the pond to check on them. But maples seem to survive unpredictable Michigan winters, so we’ll hope it pauses and waits for a few weeks.  On a long walk one sunny, snowy day, I crossed the late night/early morning path of a rabbit  and went on to enjoy the antics of the “usual suspects” of a late winter day at Bear Creek: a Bluebird pair, a Chickadee pursued by a stalking Titmouse, and a Red-bellied Woodpecker busily poking at bark, looking for beetles. On a sunny, mud-slushy short walk with my somewhat tenuous ankle, I came across Goldenrod duplexes and while watching squirrels, decided I’d share some new info I read about these mischievous mammals.

Bird Antics from the “Usual Suspects”

Our Eastern Bluebird couple (Sialia sialis) seems to be sticking around despite fluctuating temperatures.  A hardy pair of Bluebirds!  This week I again spotted the female fluttering among the fruits of invasive Asian Bittersweet (Celastrus orbiculatus) – the vine that chokes our trees!

Female Bluebird fluttering along the Walnut Lane

Female Bluebird fluttering among vines along the Walnut Lane

She will undoubtedly disperse the seeds in them in short order since birds have very quick metabolisms, if you know what I mean…

Female bluebird getting ready to disperse the seeds of a tree killer, Asian Bittersweet

Female Bluebird getting ready to disperse the seeds of a tree- killing vine, Asian Bittersweet

I wish she’d eat the Staghorn Sumac fruit(Rhus typhina) on the Western Slope! They’re native plants and are supposed to be on a Bluebird’s winter menu!

Staghorn sumac fruit

Staghorn Sumac fruit in winter

Her male partner sat stolidly on a nearby branch, keeping an eye out for any competitors.

Mr. Bluebird2

A male Bluebird sticking close to his female partner as other bluebirds darted in and out of bushes near the Walnut Lane.

On the trail that leads north from the playground, a Tufted Titmouse (Baeolophus bicolor) stalked a Black-capped Chickadee  (Poecile atricapillus), apparently trying to see where it was caching its seeds in the tree bark. No matter where the Chickadee hopped or flew, the Titmouse was right behind.  Here’s the Titmouse with its crest raised.  It does that when excited, in this case perhaps perturbed by my camera,  or as this article suggests,  by trying to snitch some seed from the Chickadee’s hiding place!

Titmouse BC3

A Tufted Titmouse traveling around a tree and its vines right behind a Black-capped Chickadee, perhaps to snitch its cached seeds!

The Chickadee looked pretty annoyed when it finally paused for a moment! Was it that annoying Titmouse or my camera?  Or was it  just its natural expression?  Who knows?

Chickadee stare

A Black-capped Chickadee who appears to be in a state of high dudgeon!

High in the trees, a Red-bellied Woodpecker (Melanerpes carolinus) made its wet “Kwirr” call as it hopped about a tree trunk, getting snow on its beak as it searched for bark beetles or other small creatures.

Red-bellied woodpecker in tree2

A Red-bellied Woodpecker searches for something to eat beneath snowy leaves caught in the fork of a tree.

Red-bellied woodpecker pecking

A male Red-bellied Woodpecker drilling for food.

As I approached the top of the Western Slope that, a Blue Jay (Cyanocitta cristata) high in a distant tree spotted me and shouted its warning call, “Jay, jay, jay!!!!”,  announcing my presence to all the other birds.  Here’s one in an invasive  Autumn Olive bush (Elaeagnus umbellata) later that day.

Blue Jay

The Blue Jay’s call often warns other birds about predators – or harmless humans like me!

Signs of Other Creatures: Tracks and the Duplexes

Rabbit tracks

Behind the Center Pond, my husband and I crossed the tracks of an Eastern Cottontail ((Sylvilagus floridanus) emerging from under a bush next to the trail.  Though you can see a rabbit almost any time of day, these tracks were likely made between dusk and dawn because rabbits generally feed at night.  In winter, their diet is mostly bark, buds and the twigs of woody plants.  Cottontails don’t usually live underground.  Though they use holes for raising young, the rest of the time, they huddle in piles of vines and brush. They will sometimes use a groundhog’s den temporarily during heavy snow – like this Wednesday’s snowstorm!

Along the path that runs just to the west of the Playground Pond, toward the benches at the top of the hill,  the Canada Goldenrod(Solidago canadensis) bulge with ball galls, the round, woody little dwellings that house the Goldenrod Gall Fly’s larva (Eurosta solidagnis) for the winter. (See the blog from January 21 for more info.)   Lots of them will successfully hatch out in the spring, but it looks like this one won’t.  Instead it probably provided much-needed protein on a cold day – perhaps for a persistent Chickadee who had to chip away for a while to get to the larva inside.

Chewed goldenrod gall

I wonder if this work on a Golderod Gall was done by a very persistent Chickadee trying to get at the larva inside.

Nearby, I found a whole patch of Gall Fly duplexes!  The holes in these galls are the neat little ones usually made by a Downy Woodpecker (Picoides pubescens).  They are experts at drilling holes to find food, after all.  Goldenrod Gall Flies must be a great source of sustenance for birds in the winter!

Duplex Goldenrod Gall

A “duplex” of Golden Rod galls from which a bird, probably a Downy Woodpecker, has extracted larvae for food.

Squirrels in the Winter

This month the Seven Ponds Nature Center in Dryden had an informative newsletter piece about squirrels, written by Lois Rheaume, a naturalist on staff there. Having read it, I decided that I needed to read more about them.  Bear Creek, of course, is full of squirrels, three different species that seem like four!

From top to bottom below:  the American Red Squirrel (Tamiasciurus hudsonicus), the Fox Squirrel (Sciurus niger),  and the Gray Squirrel (Sciurus carolinensis) which comes in two basic colors, gray or black – and variations of those.  (No, they are not a cross with a Fox Squirrel; that’s genetically impossible.)

American Red Squirrel

American Red Squirrel

Fox Squirrel

Fox Squirrel

Gray Squirrel

Gray Squirrel

 

Black morph of a Gray Squirrel

Black morph of a Gray Squirrel with a Fox Squirrel behind it

According to Ms. Rheaume, Fox and Red Squirrels were most common in our area when the land was heavily farmed.   Red Squirrels and Fox Squirrels spend more time on the ground so open farm lands suit them. Gray Squirrels spend more time up in trees, so as trees have taken over open fields and have matured in suburban neighborhoods, more Gray Squirrels have moved in.   Squirrels can move easily up and down trees because their back feet can rotate 180°!

Fox and Gray Squirrels bury nuts underground.  Using excellent spatial memory and a keen sense of smell, they find about 95% of them.  (The forgotten ones help trees to sprout in our forests.) The Red Squirrel, who grows a rusty strip of fur down its spine for the winter, makes a cache on top of the ground.

Ms. Rheaume’s piece informed me that squirrels assess acorns by rotating them quickly under their sensitive noses with their front paws. They tend to eat White Oak acorns (Quercus alba) right away because they have thinner shells and sprout more quickly.  They’re also less nutritious for them.   Squirrels are more likely to store Red Oak acorns (Quercus rubra)  which contain higher amounts of tannin to preserve them and because they contain more fat and nutrition for winter months.  Amazing what creatures know.

Some folks may not know that squirrels build nests in trees, nests that can be mistaken for those of hawks, for instance.  Squirrels prefer a tree hole on a cold, snowy night but they are frequently unavailable.  They build nests, called “dreys” in the fork of a tree or where a sturdy limb meets the trunk.  These dreys can be used for young in the summer but they can also come in handy on cold days.

Squirrel nest1

Squirrel nests, called dreys, appear more in the fall when the leaves have fallen.

Dreys end up being a foot or more in diameter and start out with a platform of small branches with green leaves attached.   Squirrels gnaw off these branches before autumn, so that the leaves don’t fall, but stay on for the winter.  Ms. Rheaume saw one dislodged by a storm.  It contained “a fluffy layer of leaves and sticks on the outside with the next ‘wall’ lined with several layers of oak leaves, making a virtual waterproof barrier for the soft grasses, shredded bark, and lichens which make up the soft bed in the center.”  According to Wikipedia, dreys have one or two “entrance/exit holes…usually close to the bottom and oriented toward the trunk which keeps the rain out.”  Sounds reasonably cozy on a cold night, doesn’t it?

Fallen queen annes (1)

It seems that the coming week will be as topsy-turvy as the last one – a huge snowstorm followed by a warm weekend.  The dry stalks of last year’s plants, like the Queen Anne’s Lace (Daucus carota) above, are succumbing to the weight of snow, wind and cold.  But through it all, the creatures of Bear Creek find ways to keep warm, find food and keep us company as the days get noticeably longer. I heard a report of a Sandhill Crane (Grus canadensis) arriving this week.  We have lots of Red-winged Blackbirds (Agelaius phoeniceus) in our yard  and we saw an obese Raccoon (Procyon lotor) taking a hibernation break and stuffing itself beneath our bird feeder.   Perhaps these springtime creatures were fooled by  strangely warm winter days or perhaps they know something else we don’t!  Time will tell.

Footnote:  My sources for information are as follows: Ritland, D. B., & Brower, L. P. (1991); Stokes Nature Guides: A Guide to Bird Behavior Volumes 1-3, Allaboutbirds.org, the website of the Cornell Ornithology Lab at Cornell University; Wikipedia; http://www.butterfliesandmoths.org; Herbarium of the University of Michigan at michiganflora.net; various Michigan Field Guides by Stan Tekiela; Butterflies of Michigan Field Guide by Jaret C. Daniels; University of Wisconsin's Bug Lady at www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/ for insect info; http://www.migrationresearch.org/mbo/id/rbgr.html for migration info; invaluable wildflower identification from local expert, Maryann Whitman; experienced birder Ruth Glass, bird walk leader at Stoney Creek Metro Park for bird identification; Birds of North America Online; Audubon.org; Nature in Winter by Donald Stokes, Trees in My Forest by Bernd Heinrich, Winter World by Bernd Heinrich, Savannah River Ecology Lab (Univ of Georgia); Tortoise Trust website www.tortoisetrust.org;  An Orchard Invisible: A Natural History of Seeds by Jonathan Silvertown; The Ecology of Plants by Gurevitch, Scheiner and Fox; other sites as cited in the text.

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: Golden Fields Full of Monarchs, a Hummer and Other Beauties and Curiosities

 

Western slope from the north2

The golden western slope of Bear Creek from the northern end – full of Monarch butterflies this week.

Blog post and photos by Cam Mannino

Blog post and photos by Cam Mannino

Open fields edged by trees have always been favorite places of mine.  And this Tuesday,in the fields on either side of the park, Monarch butterflies were everywhere!  Bear Creek may be hosting fall migrators on their way to Mexico – or we’ve just had a big hatch of  these beautiful and ecologically fragile creatures.  In fact, many butterflies, bees and darners fluttered, hummed and hovered over the swaying seas of gold in Bear Creek, while grasshoppers serenaded them beneath the tall stems.

Some speculate that humans love open fields because our ancient ancestors felt safe where they could see into the distance but escape into the trees.  I just know I’m very happy in a field full of wildflowers.

First, of course: The Monarchs and the Hummer!

After only seeing the occasional Monarch Butterfly (Danaus plexippus) this summer, on Tuesday they were floating and fluttering all over the park!  Though the Joe Pye (Eutrochium maculatum) in the Eastern Old field seems to be past its peak,  its nectar drew in a Monarch (and other butterflies below) anyway.

Monarch on Joe Pye

A monarch explores the fading Joe Pye for a sip of nectar.

I considered myself lucky to get so close – but when I started down the Western Sloping Path from north to south, wow!  Monarchs surrounded me every step of the way.  I believe I saw at least a dozen there, but I’ll share just a few who were enjoying the New England Asters.

Monarch on New Englans aster

A female Monarch on a New England Aster

Monarch hanging New England Aster2

A female Monarch butterfly dangles from a clump of New England Asters.

At the very bottom of the sloping path, I watched as two Monarchs approached and fed on the same plant.

Two monarchs New England Aster

Two monarchs share a New England aster plant.

Just at that special moment, I saw the second Ruby-Throated Hummingbird (Archilochus colubris) I’ve ever seen at Bear Creek – a female, hovering momentarily as she looked at me and then zoomed off toward the woods.  No photo, of course, but perhaps this silhouette of a hummer in mid-hover from a few years ago will help you visualize the one I saw this week.

hummer silhouette copy - Version 2

A female Ruby-throated Hummingbird paused in mid-flight at the bottom of the Western Sloping Path

Fields Full of Wildflowers and their Beautiful Visitors

Eastern Tiger Swallowtails (Papilio glaucus) fluttered quickly across the golden fields.  I just caught sight of one in the far distance on the Eastern Path on Sunday so here’s a picture from another  August, when a male landed on Spotted Knapweed, an invasive wildflower.

yellow swallowtail 2

A Tiger Swallowtail lands on Spotted Knapweed, an invasive wildflower from Eurasia.

New England Asters (Symphyotrichum novae-angliae) increasingly complement the Goldenrods’ glow as these vivid native flowers grow tall to reach their share of the thinning sunlight.

asters and goldenrod

Asters have grown tall this year competing with the height of Goldenrod and complementing its color.

Great Spangled Fritillary in the Eastern field paused on fading blossoms of Joe Pye to take a sip, just like the Monarch did.

Great spangled fritillary

A Great Spangled Fritillary pauses to sample the fading blossoms of Joe Pye Weed.

And the Silver-spotted Skipper (Epargyreus clarus) rested beneath a blossom of the same plant.

Silver-spotted skipper butterfly

A Silver-spotted Skipper explores the possibilities of the Joe Pye by hanging from a fading blossom.

About That Hum in the Old Fields…

Honey Bees (Apis mellifera), native Bumblebees (genus Bombus) and even Eastern Yellow Jacket Wasps (Vespula maculifrons ) hum among the flowers in the Old Fields.  Don’t worry; they’re much too busy gathering pollen, or in the case of wasps, eating nectar, to bother with us humans.

Bee on goldenrod2

A Honey Bee making the most of late season pollen on a Canada Goldenrod.

Always on the lookout for a quick munch, the big Canada Darner Dragonfly (Aeshna canadensis) zooms and dives over the blossoms below. This B-52 of insects consumes a lot of late summer bugs.

Canada darner in flight2

A Canada Darner flew over the reeds next to the Eastern Path, scouting for unwary insects.

Below the Darner, a modest wet-footed flower stands among the wetland reeds in the Eastern Old Field. According to Wikipedia, Boneset (Eupatorium perfoliatum) got its name because our ancestors believed that since the leaves clasped the stem “wrapping the leaves in bandages around splints would help mend broken bones.”

Boneset

Reportedly Boneset got its name from a past belief that because the leaves clasp the stem, it would help with mending broken bones.

Down in the grass, the Red-legged Grasshoppers (Melanoplus femurrubrum) sing lustily as a backdrop to all this beauty by rubbing their rasp-like back leg against their forewing.

grasshopper on joepye1

Red-legged grasshoppers chirp in the grass, preparing to mate and lay their eggs in the soil for next year.

Bumblebee buzzed softly as it balanced carefully at the top of a stem of Canada Goldenrod

Bumblebee on goldenrod

A bumblebee balancing on the tip of a Goldenrod stem.

Yellow Jackets, like all wasps,  don’t do much pollinating because they lack the fuzzy body hair of bees.  They generally eat nectar but collect bugs for the protein they feed to their young.

Yellow jacket on hemlock

A Yellow Jacket Wasp explores a tiny blossom of Queen Anne’s Lace.

What’s That Bump on the Goldenrod, Anyway?

As you’re wandering through the Old Fields, you may have noticed some strange shapes on the stalks and tips of Canada Goldenrod (Solidago canadensis).   Galls are growths on plant stems caused by insects who lay their eggs on the plants in the spring.  When the larva hatch, they eat into the plant, causing it to form a gall around them.  Inside, the larva eats until late summer when it forms a pupa which spends the winter inside that protective covering.  In spring, the adult insect emerges to restart the life cycle. Galls don’t kill the Goldenrod; they just look funny!

The ball gall is the most common goldenrod gall and is formed by  the small Goldenrod Gall Fly (Eurosta solidaginis).  With its hard surface, this gall seems like a decent place to spend the winter, doesn’t it?  During the summer, though, some wasps lay eggs in galls and their larvae hatch and make a meal of the gall fly’s.   And in the winter,  Downy Woodpeckers drill holes in galls to reach the pupae,  and Gray Squirrels chew on galls to do the same.  Obviously enough Gall Flies survive in these dwellings to start a new crop next spring, so nature stays in balance. I think this gall may have been invaded by a wasp.

Goldenrod gall2

A ball Goldenrod gall formed by the larva of a Goldenrod Gall Fly who turns into a pupa and spends the winter there – though the holes indicate that perhaps a wasp has invaded this gall and its larva may have eaten the gall fly’s.

Goldenrods also harbor the very tiny (.2″) Goldenrod Gall Midge (Rhopalomyia solidaginis) which causes a rosette gall.  Once the grub of this tiny creature hatches, the stem of the goldenrod generally stops growing but keeps producing leaves which bunch up and make a nice hiding place for a midge’s larva to grow – along with spiders and other midges who may move in.   Sometimes, as in this photo, the stem will continue to grow above the rosette gall, but it’s much more spindly.

Goldenrod gall_edited-1

A rosette gall on Canada Goldenrod created by a single tiny insect but potentially a hiding place for other midges and spiders as well.

For years I saw willows in the park that seemed to be producing pine cones at the end of their branches.  Turns out they’re Willow Pine Cone Galls, made by a tiny (about .2″) midge scientifically known as Rhabdophaga strobiloides.  The pine cone-shaped gall that its larva causes can harbor many species.  According to the University of Wisconscin-Milwaukee’s Field Station website, “Beetles, caterpillars, sawflies, cynipid wasps, midges, and the eggs of meadow grasshoppers have been found inside pine cone galls.”  They’re now on a willow on the west side of the Center Pond and can also be seen in the wetland area east of the Eastern Path.

gall

No, not a pinecone! A Willow Pine Cone gall that can harbor over 30 different species besides the larva of its original midge.

The Eastern Old Field rolls down to the Center Pond and the Western one slopes dramatically to the west.  The trails that wind across them are full of strange and beautiful creatures and the plants that feed on and live in them.  Walk quietly. Look closely.  Listen carefully.  And when nature shares a secret with you, please share it with the rest of us.

*Footnote:  My sources for information, as well as Oakland Township Stewardship Manager Dr. Ben VanderWeide, are as follows: Ritland, D. B., & Brower, L. P. (1991). The viceroy butterfly is not a Batesian mimic; Stokes Nature Guides:  A Guide to Bird Behavior Volumes 1-3, Allaboutbirds.org, the website of the Cornell Ornithology Lab at Cornell University; Wikipedia; http://www.butterfliesandmoths.org; Herbarium of the University of Michigan at michiganflora.net.; various Michigan Field Guides by Stan Tekiela; Butterflies of Michigan Field Guide by Jaret C. Daniels; University of Wisconsin's Bug Lady at www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/ for beetle info http://www.migrationresearch.org/mbo/id/rbgr.html for migration info, and invaluable wildflower identification from local expert, Maryann Whitman.