Sunday, November 19, 2017

Hibernating Bald-faced Hornets


I found two Bald-faced Hornets (Dolichovespula maculata) under a piece of rotting wood earlier this week.  Only new queens hibernate, the rest of the colony dies when temperatures drop below freezing.  These queen have already mated and will start new colonies next spring.  Assuming they survive the winter, which doesn't at all seem guaranteed given the scant protection afforded to them by their shelter.
Cold is the most obvious danger.  I didn't find anything that specifically referred to hibernating Bald-faced Hornets, but insects as a group have a wide variety of behavioral and biochemical strategies for preventing and/ or controlling ice formation in their bodies.  But many of these strategies partially rely on an insulating blanket of snow; which helps moderate the temperature of the hibernating insect's immediate surroundings; our Minnesota winters seem to be trending towards a less consistent snow cover.
Bald-faced Hornets have a bad reputation for being nasty insects that sting with little provocation.  I believe this is largely an exaggeration.  I've often watched them up close as they chew on the wood of an old bench, raw material for their paper nests.  Of course coming into contact with their large, ovoid paper nests can result in many, many painful stings.  But often their nests are high up in trees.

I'm sometimes asked something along the lines "What are they good for?"   The quick answer is they prey on other insects,  some of which are pests.  But I think the best answer is why do they have to be "good" for anything; they are living creatures in their own right and that should be enough.


Thursday, October 19, 2017

An Illustrated Life List: European Starlings

This is a re-work of a picture I did in 2014.  I liked the original concept I had of merging a sonogram with starlings calling from utility lines, but I was never satisfied with how I executed it. 

The scenery of the picture is the sonogram graph.  I wanted to highlight the starling's ability to imitate other birds, so the data points of the sonogram are shown as abstractions of birds I've heard starlings imitate.

Sonograms aren't usually depicted in field guides.   But the Golden Guide "Birds of North America" does include sonograms for many birds.  When I first started birding I found these sonograms to be more helpful in describing bird calls than the textual descriptions offered in most field guides.  I could glean a sense of a call's timing, pitch range and variation from the sonogram's blotchy plots and roughly compare this to what I heard in the field.  This though, was before recordings of bird songs were readily available online or mobile devices (cause they didn't exist!).

From the 2014 post
Don't take this as a defense of starlings; I do understand their negative impact on other cavity nesting birds (but really, who's to blame for this), but I enjoy watching starlings.  I especially enjoy listening to them for other bird sounds that they are imitating.  I frequently see them in my neighborhood on the mess of utility lines that run through the alleys and along the streets.  I envisioned these lines as the lines on a sonogram graph, with the starling's call taking the shape of the bird they are imitating; the blips on the sonogram.

Robbins, Chandler S, Bruun, Bertel, Zim, Herbert S and illustrated by Singer, Arthur. A Guide to Field Identification Birds of North America.  New York; Golden Press, 1966.

Monday, October 9, 2017

Insect Notes

A few noteworthy observations of select insect populations since May 2017

Chestnut-marked Pondweed Moth - Parapoynx badiusalis
Perhaps my favorite obscure, little moth.  The Chestnut-marked Pondweed Moth has aquatic caterpillars and is often quite abundant at Westwood Hills Nature Center in the middle of the summer.  This summer I didn't see any.  I've observed occasional population lows over the 18 summers I've been at Westwood, but never a complete absence.

Common Baskettail - Epitheca cynosura
This dragonfly usually emerges en masse in late May at Westwood over the course of one or two days.  This year not a single one appeared.

Giant Swallowtail - Papilio cresphontes
Each year a few of these more southern butterflies stray up into Minnesota.  This was the first year to my knowledge that this species has been observed at Westwood.  One individual was observed laying eggs on Prickly Ash in September.

Painted Lady - Vanessa cardui
This migratory butterfly was abundant in parts of Minnesota this fall and elsewhere in the US. 

Wednesday, August 30, 2017

Mushroom Log - Late August 2017

Laccaria ochropurpurea
Though this mushroom does show some variation in color, the differences in coloration in these photos is probably more due to differences in the lighting.

Mycena semivestipes
 Bleach-like odor, growing on a well decayed log.

Marasmius siccus
This small mushroom decomposes hardwood debris.

Suillus americanus
 Growing under white pines.  Note the brown coloration that occurs when the mushroom is "bruised".
 
Amanita sp.
A. vaginata or one of it's many look a likes.


Thursday, August 24, 2017

Mushroom Log - Late August 2017

All the mushrooms featured in this post were found in white pine stands at Afton State Park.

Lactarius indigo
I think all mushrooms are pretty cool, even LBMs.  But a big blue mushrooms is really cool!

Laccaria sp.
 Possibly L. laccata or similar species, of which there are a few.

Inocybe sp.

Possibly I. geophylla.

The two species pictured just above were everywhere in one patch of white pines.  I think it's interesting how both species are so highly variable in appearance, especially as they dry out and more or less blend together to the casual observer.

Trichloma sp.
 Possibly T. myomyces based on it's overall appearance, small size, and habitat.
 



Sunday, August 20, 2017

Mushroom Log - Late August 2017

Suillus subaureus
I found these growing under a small white pine next to the parking lot of a Little Caeser's.  Features that led me to this identification include: habitat, large size, overall orange to brown color, yellow flesh, and the dark dots on the stem (which are called glandular dots).  There's speculation that this mushroom has shifted its habitat preferences from strictly white pine to aspen and other trees as white pines were logged in the 18th century.  I wonder if the mushroom photographed has "switched" back to white pine that are planted in landscaping.  Or maybe as species it's always had fairly catholic habitat preferences and the observed change from white pine to other trees just reflects changes in vegetation (not sure if I explained that thought well, but I'm in a rush).

And by the way, I had forgotten my wallet, so I couldn't get any pizza!

Chlorophyllum molybdites
Growing in lawns in my NE Minneapolis neighborhood.  Collected by my daughter, Adele.  Note the greenish gills in the lower center photograph, this is key in seperating this species from the very similar C. rhacodes.  Also note that C. molybdites is poisonous/

Tubaria furfuracea
  
Unknown mushroom

These mushrooms were growing near and among the above.  I didn't take really good notes, but the variable cap color (changing as it dries), fragile stem, and a dark spore point to a species of Psathyrella.


Wednesday, August 16, 2017

Mushroom Log - Mid August 2017

Simocybe centunculus
A wood growing LBM with a granular sort of texture to give it some distinction.

Bolbittius reticulatus
It features a slimy cap.

Coprinellus disseminatus
The mushrooms in these photos inhabit a well-rotted stump.  I think I first noticed these mushrooms about fifteen years ago, when instead of a stump, they inhabited a rotten spot at the base of a basswood (if memory serves me correct).  We're sort of friends at this point.
 
 Mycena haematopus


Trichaptum biforme

 Xeromphalina kauffmanii




Unknown Mushrooms
Light brown spore print, growing in loose cluster along the edge of a trail that followed the edge of a deciduous woods.  Tough, especially the stem.  The stem also showed some slight granular texture.  Maybe Pholiota terrestrias, but most sources describe that species as more scaly. 
 

Tuesday, August 1, 2017

Firefly, Lightning Bug, Glow-worm

Firefly, lightning bug and glow-worm are three names that all refer to the same thing, sort of.  They are all commonly used names for a group of bioluminescent beetles in the the family Lampyridae.  Bioluminescence is the ability of some animals to create light from compounds produced within their bodies.  More specifically, firefly and lightning bug refer to the adult beetles while glow-worm refers to the larva.

Firefly and lightening bug refer to the adult stage of lampyrids, but they are actually not flies or bugs, they are beetles.  And the use of the words fire and lightning is a bit ironic since the light that lampyrids create is "cold".  All of the energy used (in the form of ATP) produces light with none lost as heat, a feat we have been unable to achieve with light bulbs so far.  The name glow-worm refers to the larval stage.  Of course they aren't actually worms at all, and to my eye are one of the least worm-like larva I've seen, instead resembling some sort of miniaturized ankylosaur.  But hey, it should really come as no surprise that commonly applied names don't stand up to taxonomic scrutiny, and something more descriptive like cold light beetle doesn't have the same ring.

There are about 170 species of fireflies in North America.  Minnesota has about a dozen species; there's no comprehensive list that I could find, and though fireflies as a group are easy to recognize, identification to species isn't always easy.

A few generalities that can be made about fireflies:
  • The larva are usually predaceous and are found in damp environs, often rotting wood.  
  • The larva usually over winter
  • Adults use their light producing abilities to attract mates, with different species often having different flash patterns.
  • Adults are thought not to eat.
see below for illustration credit
But like so many groups of organisms, there are just as many differences and variations, including:
  • Some overwinter as adults, possibly emerging when maple sap starts to flow.
  • Some firefly species are active during the day and don't have bioluminescence.
  • The adults of some firefly species are predaceous and mimic the flash patterns of other species in order to lure them in.

There's more to know and other interesting adaptations (like reflex bleeding) that I could write about, but I think I'll refer you to some excellent online resources.

Firefly.org

BugGuide 

The picture I used in the middle of this post is from an article entitled "Studies on the Flash Communication System in Photinus Fireflies" by James E. Lloyd" published by the University of Michigan Museum of Zoology, Miscellaneous Publication No. 130, 1966

Sunday, July 23, 2017

Camouflaged Looper

The Camouflaged Looper, Synchlora aerata takes the camouflage strategy to a higher level by attaching small pieces of whatever flower it finds itself feeding on.  They eat quite a variety of flowers, but are most commonly found on flowers in the composite family; David Wagner in his excellent book "Caterpillars of Eastern North American" lists ageratum, black-eyed susan, boneset, daisy, goldenrod, ragweed, and yarrow from the composite family, plus a good variety of other plants.

Camouflaged Loopers are also known as Wavy-lined Emeralds for the light green moths they eventually develop into.  They belong to the inchworm family, the Geometridae.  This family never ceases to amaze and surprise me.  It's members contain such a variety of camouflages, feeding strategies and are some of the first and last moths active in Minnesota.  I think most people would recognize an "inchworm", but don't realize how much more there is to them.

Wednesday, July 19, 2017

Little Black Toads

Toadlets of American Toads have been everywhere at Westwood Hills Nature Center.  They are about a centimeter in length and somewhere in between dark grey and black in color.  They must have just completed metamorphosis and are now on the move, dispersing through the woods.  In a few weeks they'll be a lot harder to find, settled somewhere shaded and full of invertebrates for them to eat, or possibly eaten themselves. 

I'm still disappointed that American Toads were moved from the genus Bufo and into the genus Anaxyrus.  I'm not sure what the specific reasoning was for the change, and I doubt I'd have any qualms about it; my disappointment is purely onomatopoeic.  Bufo sounds just so quintessentially toadish.  There are still toad species in the world in the genus Bufo, but not the American Toad.  Sad

Saturday, July 15, 2017

An Illustrated Life List: Spotted Sandpiper

Spotted Sandpiper, Actitus macularius under the Broadway Avenue bridge which crosses the Mississippi River between north and northeast Minneapolis.


Tuesday, June 27, 2017

June Flies

My interest in flies (order Diptera) has been increasing the past few years.  Here are a few I've come across recently.  All pictures were taken with my iPhone in and around Minneapolis in June.


Toxomerus marginatus
One of the many bee mimics in the flower fly family, Syrphidae.  The larva eat aphids, which are doing serious damage to some of the wildflowers in our backyard this year.  It's very possible the larva in the photo below is of T. marginatus.

Ptecticus sp.
 This fly is in the soldier fly family, Stratiomyidae.  According to Bug Guide there are five North American species.  P. trivittatus is the only species found in MN pictured at Bug Guide.  They are regular summer inhabitants around our compost bin.

Ctenophora nubecula
A species of crane fly, family Tipulidae.  Crane flies represent a different taxonomic branch of the Diptera.  Despite resembling a super-sized mosquito, they are harmless.

Wednesday, June 7, 2017

Painted Turtle with Snapping Turtle




A number of years ago I was witness to an odd animal sight; two small painted turtles, Chrysemys picta basking on a floating snapping turtle, Chelydra serpentina.  Nobody really believed me.

But this week I saw a similar sight (and with witnesses).  This time it was one painted turtle with one snapping turtle.  The snapper was mostly submerged with just its snout out of the water.  The painted turtle was floating just  above it.  Occasionally the painted turtle took a good nibble at the snapper.  We all expected retaliation from the snapping turtle, but none came.  The snapper barely registered the bite.

So what was happening?  We entertained a few ideas before coming up with a plausible explanation.  We speculated that the painted turtle was eating leeches off the snapper.  Later I looked for some information on this behavior.  I found a few references to this behavior, including a scholarly article from the journal Canadian Field Naturalist.  I wonder if this is a rare interaction, or maybe only occurs in certain types of water bodies.  Or maybe it's a common, but rarely observed because snapping turtles spend so much of their lives at the bottom of lakes and pond.


Saturday, June 3, 2017

Two Late May Moths

Nessus Sphinx Moth - Amphion floridensis
In the Sphinx Moth family, Sphingidae.  It's been in our backyard for a few days; its wings are pretty beat up so its usually in the grass struggling to fly.  We've been putting it on Virginia Waterleaf that grows abundantly in our yard and is in full bloom right now.  But the next time I see it, I'm going to put it on a grapevine, which is what the larva feed on.

Polyphemus Moth - Antheraea polyphemus


Giant Silkworm and Royal Moth family, Saturniidae.  Thank you Debbie for showing me this moth and not thinking it was a big leaf.

Both moths happen to feature a character from Greek mythology in their names.  Nessus was a centaur whose trickery led to the death of Heracles.  Polyphemus was a cyclops from the Odyssey.  There's a tradition of naming moths the larger North American Silkworm moths after figures from Greek mythology.  A few sphinx moths have myth inspired name, but not consistently so.  If anything, many N. American sphinx moths are named after their caterpillar's host plant.


Sunday, May 28, 2017

Late May Moth Caterpillars

Fall Cankerworm, Alsophila pometaria hanging underneath a partially eaten basswood leaf.

a. Fall Cankerworm, A. pometaria on a basswood leaf
b. Linden Looper, Erannis tiliaria on an elm leaf
c. Spring Cankerworm, Paleacrita vernata on an elm leaf
d. partially eaten elm leaf
e. Fall Cankerworm under a Brock Magiscope
f. Copper Underwing, Amphipyra pyramidoides on a basswood leaf
g. Fall Cankerworm
h. Linden Looper under a Brock Magiscope
i. Oblique-banded Leafroller Moth, Choristoneura rosaceana on basswood leaf.  I'm less certain about the id of this one.  There are a number of green leafroller moths with black heads.  I arrived at my id by cross checking the food plant database at Tortricidae.net (a site dedicated to leafroller moths) with the range maps at Moth Photographers group.  This narrowed down the choices to about a dozen moths.  Then I compared photographs of the caterpillars to my photographs.  Even if I'm wrong about the id, it was a fun process!
j. rolled basswood leaf of leafroller moth
k. partially eaten basswood leaf
l. Spring Cankerworm on elm leaf

Wednesday, May 10, 2017

Black Morel Art

I did a rough version of this picture a few years ago, but I wanted to redo it and make it available at Red Bubble.

My original intent was to put together all the "Black" Morel species and their habitat preferences that could possibly be found in Minnesota into a kind of graphic id guide.  But it evolved into something much more decorative and stylized.

If you're interested in knowing more about the various species of morels in North America, I highly recommend the Morchella page at Mushroom Expert.

Saturday, February 25, 2017

An Illustrated Life List: American Woodcock

 
American Woodcocks, Scolopax minor performing their aerial mating display.  They spiral up into the sky then zig-zag back down to ground.  Along the way, stiff feathers on the wings produce a variety of chirps and twitters.  Woodcocks display in the early spring at dusk and dawn. 
 
This dramatic display is at odds with the woodcock's normally secretive and ground hugging habits.  Everything about Woodcocks except the mating displays is built around a very terrestrial life style.  The brown and grey feathers come together to make patterns that allow them to virtually disappear into their surroundings.  Their beak is very long and skinny (and doesn't really seem to belong on the bird's small head).  It appears to pull the whole bird downward to the ground which, not surprisingly, is where Woodcocks find their food.  They poke the mud and dirt in search of worms.  Their vermicular searches are aided by a beak tip that has a sense of touch and a bit of flexibility.  Though their whole head is oriented in an earthly direction, their gaze is often directed up and outwards by eyes that are situated far back along the sides of the heads, watching for potential predators.