The Photo Club meetings are friendly and informal, with a brief discussion of upcoming activities, a short program and conclude with the opportunity to share and discuss photos. You’re welcome as a photographer, regardless of your skill level.
Ages 18+ | No pre-registration required.
Photo club meetings are always free to attend!
If you’d like to attend in person, please meet in the Riveredge Barn. If you’re joining virtually, please use the link below to connect on Zoom.
The Photo Club meetings are friendly and informal, with a brief discussion of upcoming activities, a short program and conclude with the opportunity to share and discuss photos. You’re welcome as a photographer, regardless of your skill level.
Ages 18+ | No pre-registration required.
Photo club meetings are always free to attend!
If you’d like to attend in person, please meet in the Riveredge Barn. If you’re joining virtually, please use the link below to connect on Zoom.
The Photo Club meetings are friendly and informal, with a brief discussion of upcoming activities, a short program and conclude with the opportunity to share and discuss photos. You’re welcome as a photographer, regardless of your skill level.
Ages 18+ | No pre-registration required.
Photo club meetings are always free to attend!
If you’d like to attend in person, please meet in the Riveredge Barn. If you’re joining virtually, please use the link below to connect on Zoom.
2025: The BugLady was out in a wetland today, stalking the wily Pink Lady’s Slipper (aka the Moccasin flower), a large and lovely native orchid. After she got home, she discovered a male Wood/Dog tick on her person (dark, with pale streaks), so it seemed like an auspicious time to rerun the episode about the Deer tick.
2014: The BugLady encountered a deer tick on her scalp last week (second week of March), a reminder that these are very hardy little critters – AND – that the uncharacteristically balmy weather is getting lots of stuff going early. So, here’s the deer tick story as told in a BOTW from three years ago along with some hot-off-the-presses additional information and, of course, new pictures.
The DEER TICK (Ixodesscapularis) (not to be confused with the musical group Deer Tick) is a critter whose escapades are well known to those of us who live here in God’s Country (at least they should be). It’s notorious for its ability to spread Lyme (not Lymes) disease and because its sesame-seed-size makes “tick checks” a challenge (scroll down to the ruler at http://www.entnemdept.ufl.edu/creatures/urban/medical/deer_tick.htm).
Lyme disease is an initially-flu-like disease that doesn’t go away and will escalate if ignored, and it is more treatable early than late. The CDC has a very comprehensive website with information about tests, symptoms, treatment, and prevention at http://www.cdc.gov/lyme/, (there’s disagreement about Lyme disease testing and treatment, mainly from organizations whose members have spent months and years looking for a clear diagnosis and an effective cure for this frustrating disease). Lyme disease is not “catching,” and you can’t get it from eating venison from an infected deer (but kneeling on the ground dressing out a deer puts you right down there in DT territory).
When the BugLady moved into her rural home 39 years ago, ticks were scarce, she plucked a wood/dog tick (Dermacentor variabilis) off the dog every 5 years or so, and she never saw a deer tick. In the past four or five years she has seen fewer wood ticks, but deer ticks (a.k.a. Black-legged ticks) have arrived in force and are showing their little heads by late April (chiggers are way more numerous, too). An article in Science Daily (June 22, 2011) refers to the “steady march of deer ticks across the Upper Midwest” and reports that the rate of their advance through Indiana and Illinois (having successfully occupied Minnesota and Wisconsin) is two counties per year.
Non-feeding adult DTs are very small (about 3mm long) and flat and dark (females may look blood-red when they’re empty but not when they’re full, and males are dark and vaguely speckled). They have eight black legs and a black “shield” (called a “scutum”) in back of its head. DTs don’t have any white/light markings on the scutum, but wood ticks do. A feeding adult female looks like a tiny, over-filled, blue-gray balloon (“as tight as a tick”) (the BugLady is trying to avoid comparisons to grapes here, lest she put BugFans off their feed).
DTs lead a complex, three-stage, two-year life. All three stages are mobile and all three require a blood meal that can take three to five days to complete. Adult DTs are fairly impervious to frosts and can be out and about on winter days that are above freezing. In spring, Mom has a big meal (adult males rarely feed), mates, drops to the ground, and lays thousands of eggs. The first post-egg stage is a minute’ six-legged larva that feeds once during mid-summer on a bird or a small mammal (it’s especially fond of white-footed mice). The well-fed larva leaves its host and overwinters in the leaf litter. The following spring it molts into a poppy seed-sized nymph that feeds again (another mouse, maybe, or a raccoon or squirrel) and then molts into an adult that becomes active in fall. Adults favor large mammals like white-tailed deer.
Ms. DT finds Mr. DT through the magic of aggregation pheromones (chemical “perfumes”) that cause DTs to gather in groups, allowing boy to meet girl. They may mate on a host, on vegetation, or on the ground. He dies after mating a few times; she dies after laying eggs.
Where does a DT pick up Lyme disease? Typically not from Mom, even if she’s carrying it. An uninfected larva or nymph can pick up the disease from its host; an infected larva can transmit it to its host, and once they’ve picked up the infection, ticks retain it for the rest of their lives. The general estimate is that in high-Lyme areas, 25% of nymphal DTs and 50% of adults carry the bacterium that causes the disease, but according to the American Lyme Foundation, fewer than 5% of DTs south of Maryland are carriers. Dog ticks do not spread Lyme disease (but they are not totally innocent bystanders, either).
DTs are classed as sanguivores (animals that ingest fresh blood). They’re opportunistic – to find a host, they’ll often wait at the tips of vegetation in what is called the “questing position,” sensing the air, waiting for something large to brush against them (top picture http://blogs.scientificamerican.com/observations/new-map-shows-that-most-lyme-infected-ticks-are-in-northeast-northern-midwest/ then scroll down for a Lyme map – we no longer presume that someone who tests positive for Lyme has been “up North”). The biggest mortality factor for ticks may be starvation, and harsh climate can also affect them. They typically aren’t eaten by predators because they’re simply too small to see.
Here’s the DT’s pedigree: they’re in the family Ixodidae (the hard ticks), which is in the order Ixodida (ticks), which is in the Class Arachnida (spiders and friends), which is in the Phylum Arthropoda (insects, spiders and crustaceans). They are, potentially, found wherever their final host, the white-tailed deer, is found. Most DTs live east of a line from Minnesota to Texas, http://www.cdc.gov/ticks/geographic_distribution.html.
Along with Lyme disease, DTs can pack a number of disease-causing bacteria and parasites into that tiny body, and scientists are still finding new ones. In the three years since the original DT post, a West Nile virus/meningitis-like disease called Powassan virus has been added to the deer ticks’ arsenal. Tiny nymphal ticks far outnumber their elders, and because nymphal ticks are most active during the period when we’re all outside in summer, bites from nymphal ticks are presumed to be the cause of most human infections. Pets can get Lyme disease, too; talk to your vet.
Also new on the Wisconsin scene is a new tick species, the Lone Star tick, which carries its own set of unpleasant diseases, including one that may trigger in the “bitee” a lifelong allergy to beef, pork, and lamb.
Scientists have discovered some intricate ways that DTs fit into the ecological jigsaw puzzle:
1) In eastern oak forests, a big load of acorns (a “mast year”) results, for the next few years, in lots of white-footed mice and deer, which means fewer gypsy moths (mice eat their pupae) and more hosts for the DTs. More DTs mean more Lyme disease. Fewer acorns mean fewer mice, more gypsy moth outbreaks, and less Lyme disease.
2) The incidence of Lyme disease is linked to the presence of deer, but it also reflects the population cycles of certain small mammals. A decrease in predators like the red fox (coyotes have taken over) results in larger populations of potential tick hosts like mice and chipmunks and more Lyme disease (remember, though deer are important in the DT’s end game, most people probably get infected by a DT nymph, which hasn’t met a deer yet).
3) DTs like white-footed mice, and white-footed mice like woodlands. Research in Illinois shows that DTs are gaining a foothold in Illinois prairies by setting their sights on prairie voles instead.
So – stay inside until winter? Through winter? Nope. Standard precautions include wearing light-colored clothing, using repellents containing DEET, and pulling socks over your pants cuffs to make it harder for ticks to duck and hide. According to the CDC, “In most cases, the tick must be attached for 36-48 hours or more before the Lyme disease bacterium can be transmitted,” so do thorough tick checks of your hairline and all your nooks and crannies.
…………………………………………..the BugLady feels like stuff is crawling on her……………………..
Here’s a rare glimpse into the BugLady’s “BOTW Future” file, which is packed with pictures of identified insects that she hopes have a good story to tell, with semi-identified insects, and with (mostly) her “X-Files” – the Unidentified. (The file probably reflects the state of the BugLady’s brain.) It’s what she sees as she selects the bug of the week.
Traditionally, the BugLady goes on sabbatical for the month of June, but she’s going to sneak away a bit early this year. Why? There’s an old riddle,
“Why did the glaciers retreat?”
“To get more rocks.”
The BugLady needs more pictures.
Lest your inbox grow cobwebs, she will post a tasteful rerun each Tuesday until she gets back.
FROM THE FILE:
BEE X23 (on bergamot)23-1 – a busy little bald bee.
BEETLE MILKWEED ANNULATUS HL22-2 – Not our common Red milkweed beetle (Tetraopes tetropthalmus). There are two species here that are adorned with those lovely double rings on the antennal segments – T. femoratus (which has red on its legs, unless it doesn’t), and T. annulatus, sometimes called the Ringed milkweed beetle. The BugLady would happily call this T. annulatus based on appearance and habitat (dry, sandy areas), but it was sitting on Common milkweed, which is not listed as one of annulatus’s food plants. Is the BugLady overthinking this? Probably.
TULE BLUET DAMSELFLY21-2 – with a bunch of water mite nymphs on its abdomen. The BugLady knows who this is, but she’s written biographies of a number of other bluets, and the details of their life histories don’t vary a lot. Besides, she promised that she would not march methodically through the species lists of Wisconsin dragonflies and damselflies.
So many wasps!!!
BRACONID15-22 – someday the BugLady is going to write a Braconid Wasps 101 episode (they’re a big and important family) but first she needs to figure out which of her wasp pictures are braconids, because they can look similar to Ichneumon wasps (an even bigger family). This one seems to be ovipositing in the flower.
WASP ICHNEUMON Latholestes17-10 – maybe a braconid.
X WASP17-1 – also maybe a braconid
WASP ICHNEUMON RNC22-1 – a large and handsome Ichneumon.
WASP MISTLETOE SLB24-3 – this Ichneumon (probably) was exploring the flowers of Eastern dwarf mistletoe.
WASP FBMP OOF24-2 – an odd little wasp that joined the BugLady on the Hawk Tower on a cool day in mid-November.
X MOTH20-7 – this handsome, largish moth looks like it should be in the genus Haploa but…..
FLY DEER RNC23-2 – looks like a deer fly, but cinnamon- colored?
PLANTHOPPER NYMPH13-1 – isn’t this a little cutie!
SPIDER WAUB24-1 – what a lovely, almost translucent spider!
X LONGHORNED BEETLE HL15-2 – enjoying the wild geranium one spring day.
WEEVIL EP12-1 – Isn’t this a great little weevil? The BugLady scooped it from the surface of an ephemeral pond, but she doubt’s that it’s an aquatic species – more likely it was sitting on a leaf and got dislodged.
Running crab spiders, in a separate family (Philodromidae) have been mentioned briefly throughout the years – here’s their story.
They are “running” by both name and by inclination – they move along smartly, and Philodromidae comes from the Greek “philodromos,” meaning “lover of the race/course.” There are 92 species of spiders in this widespread family in North America, and they’re usually found on the stems and leaves of plants. Philodromuis and Tibellus are common genera.
These are not flashy spiders – most are small (measuring less than ½” long), flat-bodied, and drab. Many (but not all) are crab-shaped like the Thomisids, but in Philodromids, the second pair of legs is noticeably longer than the first. Eye arrangement is an important tool in spider ID – here’s what it looks like to stare two genera of Philodromids in the face https://gnvspiders.wordpress.com/7-philodromidae-running-crab-spiders/.
Philodromids don’t spin trap webs, but they do generate silk to make egg sacs and to form drag lines that catch them if they catapult off of a leaf in pursuit of prey or if they have to bail in order to avoid capture themselves. They are, of course, carnivores that eat any small invertebrate that they can ambush and subdue, including other spiders, and they are small enough to become prey of larger spiders, themselves.
Most sources said that their venom (should they even be able to puncture your skin) might result in some pain and swelling, but is not considered dangerous.
Males encounter females as they wander the landscape. She leaves a trail in the form of a pheromone-laden silk dragline; he catches up with her and romance ensues. She conceals her egg sac and guards it (like the female Philodromus guarding eggs that she had stashed in an empty beech nut shell) until her young hatch toward the end of summer, which markedly enhances the spiderlings chances of survival. The almost-mature spiderlings overwinter sheltered in leaf litter and under tree bark and mature the next year. A bitterly cold winter takes a toll on overwintering Philodromids.
The most common Philodromid genus is PHILODROMUS, flat spiders that look similar to the Thomisid crab spiders. There are 55 species in North America and about 200 more elsewhere. They’re found on vegetation, but also on the ground or on walls. Larry Weber, in Spiders of the North Woods, writes that Philodromus spiders are often found in trees (and sometimes inside the house, high on the wall), and that he has collected immature Philodromus spiders on the snow in early winter.
Philodromus spiders don’t spin a web but they may create a silken shelter.
With their cylindrical abdomens, spiders in the genus TIBELLUS (tib-EL’-us), the Slender crab spiders, are un-crab-like crab spiders. There are seven species in North America and two (or three) in Wisconsin, and some are striped and others are not. Based on the presence on the abdomen of both stripes and of two spots toward the end, the BugLady thinks she’s photographed Tibellus oblongus, the Oblong running spider, which has a patchwork range across North America https://bugguide.net/node/view/143110/data and is also widespread in the northern half of the Old World.
When a male Oblong running spider encounters a female, he taps her rapidly with legs and palps, and if she’s agreeable, she remains motionless. He spins a “bridal veil” that covers her and fixes her to the substrate. When the show is over, he leaves (in a rush) and she releases herself from the veil.
Today’s Science Word – the Oblong running spider is referred to as an “epigeal” organism, which means that it’s found on/above the soil surface and does not tunnel, swim, or fly. Oblong running spiders are often seen stretched out on grass leaves – the first two pairs of legs forward, the third pair hanging on, and the fourth pair extended back.
Like other spiders, Philodromids have superpowers, and one is their ability to walk on smooth, vertical surfaces without sliding off. How do they do it? Scopulae (scopulas). Alert BugFans will recall that many bees have clumps of hairs – scopa/scopae – on their legs or abdomens that allow them to collect and carry pollen. Same root word – the Latin “scopa” means “broom,” “twig,” or “brush” but scopula is the diminutive form (mini-brush). Scopulae are dense tufts of hairs that are found below the claws and at their tips on the feet of walking or wandering (non-web-spinning) spiders. The ends of those hairs are further fragmented, forming many, microscopic contact points for the spider’s foot. This creates a natural adhesion that is sometimes enhanced by liquid excreted from adhesive pads (alternately, one source suggested that the scopulae respond to a super-thin layer of water that covers most surfaces).
This week’s episode is a rerun from the very early days of BOTW.
The BugLady loves it when the research she is doing makes a sharp turn toward History.
Galls are mentioned by (very) early observers like the philosopher Theophrastus (371 to 287 B.C.) whose two botany books, Enquiry into Plants and On the Causes of Plants, influenced scientific thinking for the next 1500 years. People have been pondering the mysteries of galls for a long time, although not all of the hypotheses have been righteous ones. For example, because they were considered “supernatural growths,” galls were used to foretell the future. In the Middle Ages, their contents were examined (much tidier than chicken entrails). Spiders signaled pestilence; maggots meant either famine or a plague among cattle; flies – war; and ants – a bountiful harvest. In 1686 Malphigi suggested that galls were swellings that plants (like people) developed due to being stung by insects (but he straightened out and went on to discover capillaries and to have the Malphigian tube named after him).
Galls 101, https://uwm.edu/field-station/bug-of-the-week/galls-i/, provided an introduction to the biology of galls and gall-makers. Short version: “Better living through chemistry.” This week’s BOTW features a few oak galls and a grape gall. Remember, of the 2,000-plus kinds of galls found on North American plants, 800 different kinds form on oaks (genus Quercus).
Cynipid wasps, which mainly target stems and leaves, are very big players in the oak gall game. The galls caused by some Cynipid wasps are very high in tannin/gallotannin (giving them the bitter taste that gave rise to their name, gall). Tannic acid is produced routinely by many plants (the plant’s strategy is to make itself unpalatable to grazers), but galls contain the highest tannin concentrations on most plants. It has been suggested that the gall-makers enjoy some “tannin-perks;” since tannins are somewhat anti-microbial, high-tannin galls may protect the larva against fungi and bacteria.
Interesting as they are to Nature Appreciators and to Scientists (they are, after all, “tumors” and their dynamic in that area is being studied), galls have a history of human commerce and use that goes back thousands of years. They have provided food, medicine, lamp fuel (in Greece, from a gall caused by a wasp named Cynips theophrastea), chemicals for tanning hides, dyes for fabric, leather and hair, beads for necklaces, and inks for tattooing and writing.
Aleppo galls (produced by Cynips gallae-tinctoriae on certain Turkish/Eastern Bloc oaks) have the highest concentrations of tannin among the galls, 50 – 65%. Historically, Aleppo galls provided a strong astringent and a treatment for fevers, burns, mouth ulcers and toothache. They continue to be important trade item, now used more for tanning and dyeing and as an ingredient in inks.
The presence of traces of iron-gall ink in the Dead Sea Scrolls makes for a pretty impressive pedigree. S.W. Frost, in Insect Life and Natural History, wrote in 1942 that “in some places, the law requires that permanent records be made with ink derived from gallnuts……The Aleppo gall has been specified in formulas for inks used by the US Treasury, Bank of England, German Chancellery, and the Danish Government.” The downside of iron-gall ink is the fact that it tends to fade after, oh, 1,500 years or so, and by that time, it may have discolored your paper, too. Google “oak gall ink” or “iron-gall ink” for the recipe; you can join the artists who explore older media – and the forgers of old documents – in reviving this ancient ink.
Oak-Apple Gall – There are about 100 kinds of these marble-to-ping-pong-sized galls; they grow on a leaf’s mid-vein or on the leaf stem (petiole). Some kinds have thin outer shells with fibrous insides, and others are denser. The oak apple pictured is occupied by a single larva. In fall, when you find these on the ground among the fallen oak leaves, check to see if there is a tiny exit hole and think about the size of the full-grown wasp that made it. Stokes, in Nature in Winter (great section on galls), tells of opening an oak apple gall that held about 200 ant eggs along with their nursery workers, and he has also found nests of mud wasps inside.
Oak Bullet Gall – Because they form from the woody tissue of the twig, these half-inch galls are very firm and can stay on a tree for several years. There are about 50 kinds of oak bullet galls, and some secrete a sticky “honeydew” that attracts other Hymenopterans- ants, bees and wasps. One source said that in exchange for the honeydew, the honeydew-eaters discourage parasitic wasps from laying their eggs in the galls. But, another source mentions attacks on bullet galls by parasitic wasps that insert their ovipositers into the gall and lay their egg on the gall-maker’s larva. Birds may peck open the gall and go after the larva.
Woolly Oak Leaf Gall – These attach to the mid vein (usually) or side veins (sometimes) and they look like cottonballs. They grow on the underside of the leaf, and they are easier to see as the leaves fall. Based on this one sample, it looks like they may have a “vampire-like” effect on some surrounding tissue.
Grape Phylloxera Gall – In 1850, there was only one species of grape being grown in all the vineyards of Europe. In about 1860, the Grape Phylloxera (a wingless aphid about 1/20” long) was accidentally introduced from its native North America. The rest, as they say, is history. By 1880, the little critter had traveled to Australia, Algeria, South Africa, and via a different route, California. One-third of French wine-producing grapes, about 2 ½ million acres, were wiped out (Mother Nature usually finds a way to deal with monocultures).
While leaf galls seldom damage a plant, a plant with grape phylloxera leaf galls has root galls, too, and the root galls weaken and stunt the vine. The French fought back, and after burying live toads under the vines to draw out the poison failed to work (True!), they imported the rootstocks of resistant American Fox grapes both to graft the French vines onto and to develop hybrids from – all the while “dissing” the quality of the American grapes. Each of the leaf galls may house a teeny, yellow Aphid Mom and hundreds of eggs and/or nymphs.
Despite the galls and the withering, the leaf continues to function.
And by the way, it really bugs/galls the BugLady that much of the information about these generally harmless growths is found on sites that have a pest control and forestry-pest bias. The accounts invariably end with some variation of “These are harmless and don’t measurably damage the plant, but you don’t like the looks of them, so here are some chemicals you could throw at them.”
This concludes Galls I – How They Do That, and Galls II – A Date with History. Coming eventually, Galls III – Oddball Galls.
Go outside – look for galls!ody in the past five days.
The BugLady has been curious about the status of Zebra and Quagga mussels since she posted an episode about them in 2016 (“A Tale of Two Mussels – the One-Two Punch”). Here’s the original post (slightly tweaked and clarified), with a summary of her recent search of the literature at the end. Put your feet up and grab a beverage.
Spoiler alert – although there continue to be new articles about these mussels, many are a rehash of older information, and it’s frustrating when agencies do not date their information pages (you know who you are), so it’s hard to say if they’ve been updated.
2016 – When the BugLady started researching zebra mussels, it became apparent that the story of this non-native, invasive mussel was inextricably entwined with that of an equally-alien and equally-invasive mussel, the quagga mussel. And also that we are, as a species, appallingly slow learners.
Zebra and quagga mussels are in the Phylum Mollusca, a diverse bunch that includes snails and slugs, limpets, clams, scallops, squid, octopi, and cuttlefish. Within the Mollusks, they’re in the order Bivalvia, and in the family Dreissenidae.
Zebra mussels (Dreissena polymorpha) and Quagga mussels (Dreissena bugensis) have traveled far from their native haunts, the Caspian Sea drainage of western Russia, but they have settled nicely into their new homes in America, hitchhiking through the Great Lakes and inland lakes and rivers on boats, boots, bait buckets, and on the feet of waterfowl. Zebra mussels were first identified in the US in 1988 in Lake St. Clair, just east of Detroit, and they reached Wisconsin by 1992. In 2010, they were found in 130 Wisconsin lakes and rivers.
Did they hoof it over here on their own? They did not; like most of us, they came over on the boat. They undoubtedly arrived in the Great Lakes in the ballast water of ships that ply international waters, as have a rogue’s gallery of hardy gatecrashers (more than 180 species, so far) – a number of North American organisms have been toted to Europe in the same fashion.
Here’s the physics of it: while they’re in their home ports, European vessels take water (plus whatever is swimming in that water) into tanks built on the inside of the ship’s hull, and this “ballast water” helps keep the ship upright. A ship carrying a small cargo needs lots of ballast, but as it loads more cargo, it discharges ballast water (plus whatever’s swimming in it) https://en.wikipedia.org/wiki/Ballast_water_discharge_and_the_environment#/media/File:Ballast_water_en.svg. Ocean-going ships routinely enter the Great Lakes via the St. Lawrence Seaway, and equally routinely, have emptied their ballast water into the Great Lakes. In 1993, a difficult-to-enforce law was passed that required incoming ships to replace their home-grown ballast water with ocean water before entering the Seaway,
In 2011, New York State, gatekeeper for the St Lawrence Seaway, proposed stiff, new regulations about ballast water management/treatment. Three (short-sighted) Midwestern governors pushed back, citing concerns about job loss, even though some innovative alternative transport was suggested at the time.
Zebra and quagga mussels turned out to be plenty adaptable – although they originated in salt/brackish water, they quickly adjusted to fresh. They are bottom dwellers that live in clusters in great, huge, astronomical numbers on the floors of lakes (at one site in Arizona, quagga mussels number 35,000 per square meter).
When quagga mussels arrived, they out-competed the zebra mussels. Although their life histories are similar, the two mussels prefer different habitats. Zebra mussels like water depths of 6 to 30 feet, and quaggas can live as deep as 400 feet, so zebra mussels grow closer to shore, and quaggas thrive through the deep basins of the Great Lakes. Quaggas necessarily have a much wider temperature tolerance. Zebra mussels prefer hard surfaces to grow on, but Quaggas thrive on softer, siltier lake floors. Both species eat all day, but quaggas continue feeding during the winter, when zebra mussels are dormant (you snooze, you lose). The BugLady’s photos show them as most people experience them – as “empties,” cast up on the beach.
Mussels are “filter feeders,” which means that they suck water in through a siphon and run it over their gills. Food particles, zooplankton, phytoplankton, and nutrients (and pollutants) are strained out of the water by cilia in the gills and are moved to the mussel’s mouth, and the water is expelled through a second siphon. Wastes are released as mucous-covered, organic packets called pseudofeces (vocabulary word of the day). An inch-long zebra mussel can filter a liter of water a day. One liter per day x Biblical numbers of mussels = large bodies of very clean water.
At first, some people were thrilled – “Yay, the lake is clean again,” shouted the headlines. Cities around Lake Erie had been battling pollution in the form of algal blooms due to excessive nutrients (fertilizer) in the water. In short order, you could see the bottom of the lake again (it’s called “nutrient bioextraction,” and it can be a useful tool in controlled situations where the bivalves are removed when they’re finished eating and processed into animal food or, ironically, fertilizer).
However, the water was crystal clear because there were so few nutrients left in it, and native species that depended on the food in those liters of water were out of luck. It was an all-out attack on the base of the food web. Zooplankton feed on phytoplankton and are fed upon by larger animals, including tiny fish, which, in turn, feed bigger fish and a variety of other vertebrates. But nutrient theft is not the only problem with these mussels.
Quaggas eat algae, but they’re picky, and non-toxic algae are their favorites. What’s left after they feed is higher concentrations of the more troublesome algae.
Light is able to penetrate deeper into that nice, clean water – UV rays are bad for the very young fish but great for plants, opening the door for more algal blooms. Decaying algae, some carrying harmful bacteria, wash up on beaches or lurk just offshore.
The clear water can allow thick growths of other aquatic plants, too, fertilized by nutrient-rich mussel poop. Dense aquatic vegetation discourages swimming, fishing, and boating.
Our native shellfish are indicators of the health of their environment. The invasive mussels turn lake beds hard and lumpy, with wall-to-wall shells, making it hard for native bivalves to find favorable habitat. To add insult to injury, zebra mussels will piggyback on native mussels, hindering their feeding and ultimately smothering them. Great picture at: http://www.startribune.com/mussel-bound-lakes-could-imperil-birds/133021828/. Said one fisheries biologist, “When I’m diving in the Mississippi River, if I come up with a ball of zebra mussels, I know that when I break that open, I’m either going to have a snail or a mussel — a native clam — inside that ball of zebra mussels.”
Old zebra and quagga mussel shells wash up on shore, often in sharp fragments, problematic for barefoot beach-goers.
Zebra mussels overgrow anything that stands still long enough, especially pilings and other underwater surfaces, and they clog utility water intake/cooling pipes, requiring costly fixes. Researchers in a few northern lakes have observed an odd (and one-sided) association – zebra mussels growing on the backs of clubtail dragonfly naiads (immature clubtails may live underwater for several years, giving mussels plenty of time to gain a foothold). Their exoskeletons are effectively glued shut by mussel filaments on the thorax, where the exoskeleton normally splits to release the adult dragonfly, so naiads crawl up on shore and die there, unable to emerge.
As they feed, quagga and zebra mussels accumulate toxins, with some pollutants occurring in their tissues (and their pseudofeces) in concentrations measuring many thousands of times higher than in the surrounding water. Those toxins (including Clostridium botulinum) get passed up the food chain in a process called biomagnification.
A mass of pseudofeces on the lake’s floor requires oxygen in order to decompose.
Lake Superior has mostly avoided this mess, probably due to a combination of its much colder temperatures, lower levels of nutrients in the water, and its water chemistry – very little calcium for growing strong shells.
Mussel reproduction is external and chancy. Males and females release their bodily fluids into the water, nature takes its course (aided by water currents and propinquity), and fertilized eggs hatch into a life stage called veligers. An adult female can produce as many as a million eggs annually, and her life span is three to five years, but the attrition rate for eggs and veligers is huge (they’re even eaten by filter-feeding adults). Mom and Dad may be stuck in one spot, but their offspring are, temporarily, free-swimming, and currents can carry them great distances. Veligers swim and feed for four or five weeks before they must attach, and they mature by their first birthday.
What slows these critters down?
Fish, like yellow perch and redear sunfish, and waterfowl, especially diving ducks like goldeneye and scaup, have learned to love the invasive mussels (98% of a Lesser Scaup’s diet is zebra mussels). Kudos also go to the equally alien and equally invasive quagga-eating Round goby fish. Alien species that become invasive do so because they have left their native predators behind. In this case, the predator caught up with the mussel, but, alas, this aggressive little fish damages native fish populations, too.
A patented bacterium called Zequanox targets these two mussel species only and has a 90% mortality rate, but it’s far too expensive to apply to a Great Lake. There’s a copper-based treatment, too.
Unusually warm water – In 2001, the water temperature in parts of the Upper Mississippi reached 89 degrees F, and masses of zebra mussels died.
Good news-Bad news: For zebra mussels in the Great Lakes, the show is over, but they’ve simply been replaced by quaggas, and scientists doubt that the Great Lakes will ever return to their pre-alien-mussel state. At this point, Lake Michigan (the 6th-largest freshwater lake in the world) is essentially a man-made ecosystem that’s being managed as a fishery, because the base of the food web is so messed up.
For those people whose attitude toward alien species is “Get over it – A species is a species! New species = more biodiversity,” the BugLady has one word. “Seriously???”
For all your invasive species needs, remember our own Southeastern Wisconsin Invasive Species Consortium (SEWISC), https://sewisc.org/, a wealth of information about invasive species already in the state and on the horizon.
Be assured that the BugLady did not use any of the information presented in the article about “Zebra Muscles” (ain’t Spellcheck grand?).
An ounce of prevention is worth a pound of cure – it can be time-consuming and expensive to try to get rid of them once they’re established (and they’ve usually been around for two or three years by the time anyone notices them). Most boat launches have signage about hosing off the trailer, boat, live wells, bilges, and motor, but the list should also include swimsuits and wetsuits – the veligers can live for three to five days out of water.
Researchers in Minnesota drew a direct line from large Zebra mussel infestations in inland lakes to some staggering increases in mercury levels in game fish in those lakes (up 72% in walleyes and a whopping 157% for yellow perch!). In the waters well-filtered by invasive mussels, walleye fry fail to thrive.
Sheephead, pumpkin seed sunfish, and carp will eat Zebra mussels, but apparently, non-native mussels are less nutritious than the native mussels, and the fish are stunted (the BugLady is blown away that someone figures these things out).
QUAGGA MUSSELS
The belief in Lake Superior’s resistance to Quagga and zebra mussels turned out to be wishful thinking, but the populations seem localized – Apostle Islands, Isle Royale, and a few harbors. Water that averages 40 degrees does seem to discourage them.
The population of Whitefish has plummeted by 80% in some parts of the Great Lakes, due to Quagga mussels. There are estimates of quadrillions of Quaggas in the lower Great Lakes.
Quaggas may have completed their conquest of Lake Michigan, but their spread into our inland lakes is just starting. They were recently found in Geneva Lake, a deep lake whose substrate is 95% sand. In a survey they did at Geneva Lake, the DNR found that a quarter of the boats had been used on a different water body in the past five days.
Leaf miners have been mentioned in these pages before – even the Aspen leaf miner (Phyllocnistis populiella) has appeared briefly. When she did a little more research, the BugLady was ecstatic to discover that Aspen leaf miners have an association with EFNs, one of the coolest things she’s ever found out about in her 16 years of writing BOTW (more about that in a sec). Here’s its story.
First of all, a quick and dirty leaf miner review. They are (primarily) the tiny larvae of a variety of species of fly, beetle, moth, or sawfly (Hymenoptera), and they are everywhere. They mostly feed on sap or tissue that they encounter as they chew their way around inside a leaf, between its top and bottom layers, some feed in fruit, and some can process plant tissues that are toxic. Leaf miners are found on plants in most plant families (as J. R. Lowell once said, “There’s never a leaf nor a blade too mean to be some happy creature’s palace.”), and some are extreme specialists, using only one or just a few plant hosts. They are often active in mid-to-late summer, and they transform plant energy into animal energy for the birds and insects that know their secret hiding places.
They create distinctive patterns that, along with the identity of the plant, help us to name them. Mines are roughly divided into three categories – serpentine, blotch, and tentiform. Most mines and their miners do not cause significant damage to their host – as J. G. Needham said in “Leaf-mining Insects” (1928), Not only does their minute size partially excuse them, but in feeding habits most are very precise and economical of tissues. They take just enough to sustain and mature their own lives, and they injure little tissue save that that they ingest.”
There are a dozen members of the genus Phyllocnistis (from the Greek meaning “leaf scraper”) in North America. They’re in the family Gracillariidae, the Leaf Blotch Miner Moths, and they are small and fringed, with wingspreads under ½,” (“micromoths” – another not-quite-scientific designation). Their larvae, flattened and rudimentary, spend their first three instars chewing serpentine trails in the leaf tissue, guzzling sap, and leaving behind a trail that’s punctuated by a line of frass (bug poop) (an “instar” is the active, feeding stage between molts). The larva doesn’t feed in its fourth and final instar; it gets itself to the margin of the leaf, where it spins a cocoon and pupates in a spined pupal case (some kinds of leaf miners drop to the ground to pupate, but not this bunch).
The Aspen leaf miner stars in a number of Extension horticultural bulletins, but its impact, other than cosmetic, tends to be minimal. If there’s a black sheep in the genus, it’s the Citrus leaf miner https://bugguide.net/node/view/1318589/bgimage.
COMMON ASPEN LEAF MINERS, aka Aspen serpentine leaf miners, are found across southern Canada and the northern half of the US, wherever quaking aspen grows. Some sources said that poplar and cottonwood are also used as hosts, and some said that the main host is aspen, and some said that mines found on cottonwood and poplar are made by a different species. The tiny moths have pale, narrow wings and long-ish antennae, and they often perch slanted, with the front half of their body “on tiptoe” https://bugguide.net/node/view/1582507/bgimage.
For a small, relatively harmless insect, there’s a surprising amount of biographical information available. They overwinter as adults, avoiding freezing through careful selection of a winter shelter and because of their ability to supercool themselves, dropping their freezing point. Counterintuitively, they prefer to overwinter under spruce trees rather than aspens, because the deeper snow cover below the aspens translates to wetter conditions as the air warms, and ice in a late freeze.
Romance blossoms in spring, and females lay their eggs on the edges of emerging leaves, near the tip, usually only one egg per leaf, and then they fold the edge of the leaf over to protect the egg until it hatches. When it does, the larva https://bugguide.net/node/view/204391/bgimage, chews through the floor of the egg, directly into the leaf, where it will live until it emerges from its pupa as an adult in fall.
Larvae eat the sap that they generate while tunneling. A research team tracked the mining habit and found that:
When the larva gets to the midrib, it turns toward the leaf’s base, and when it gets there, it turns again and follows the leaf margin for a while before heading for the midrib again;
Sometimes more than one egg is laid on a leaf. A larva may not know that it has company in the leaf, but if two larvae discover each other, they generally feed and pupate on opposite sides of the midrib;
They don’t re-mine an already-mined trail;
Larvae pupate at the edge of the leaf.
Heavy feeding on the epidermis of a small leaf can interrupt its photosynthesis, causing leaves to dry, turn brown, and fall prematurely, but aspens have lots of leaves, and the Common aspen leaf miner larvae, as Needham said, don’t eat much.
And Now for Something a Little Different III Timberdoodle redux
Howdy, BugFans,
This episode was originally adapted from the Spring, 2010 issue of the BogHaunter, the newsletter of the Friends of the Cedarburg Bog, written by the BugLady wearing a different hat. It’s further revised from a BOTW of seven years ago – new words and new pictures.
Woodcocks are wonderful birds with a great story. They were a big part of the BugLady’s childhood – their return to our brushy fields was celebrated each year and it was (and still is) a race to see who would hear the first one (thanks, Mom, thanks, Dad).
American Woodcocks (Scolopax minor), family Scolopacidae, are long-billed, big-eyed, short-legged, round-winged, Robin-sized birds. The Cornell University All about Birds website says “Their large heads, short necks, and short tails give them a bulbous look on the ground and in flight.” Woodcocks are a dumpling of a bird – about 10 inches long, weighing up to a half-pound, with big eyes, very short legs, and a very long bill (2 ½” to 2 ¾ “). Females are larger than males and have longer bills, too.
Woodcocks are shorebirds that are not tied to the shoreline – upland game birds, the “Landlubbers” of the shorebird family. These odd-looking birds (the BugLady has read that hunting dogs find them odd-smelling, too) have many nicknames, like “timberdoodle” “mudbat,” “brush snipe,” “bog-sucker,” “hokumpoke,” and “night partridge.”
A look at where a woodcock lives and what it eats explains its adaptations. Short, wide wings are perfect for flight through close, brushy areas. A woodcock is a bundle of adaptations. Short wings make it easier to maneuver in the brushy fields, woody edges, wet meadows, and open woodlands that they call home, and the fact that they are able to fly slower than any other bird – 5 MPH – serves them well in those spots.
Their superb camouflage makes it impossible to spot them before they fly, so most views are rear views as they exit the scene. The BugLady once unknowingly stood near two young birds for about five minutes until they couldn’t stand it anymore and departed, startling her with their whistling wings (there have been some interesting studies of birds’ tolerance of nearby humans – birds are more distressed by someone who stops than by someone who strolls by).
Most of their adaptations have to do with their feeding habits. That long bill allows a woodcock to extract earthworms and other invertebrates (snails, millipedes, spiders, flies, beetles, and ants) from deep in the moist soil. The tip of the bill is both flexible and sensitive and can be opened without opening the base. Worms are slippery little devils, and roughened surfaces on the tongue and upper bill help the bird to get a grip. Which is a good thing – a woodcock may eat its weight (about a half-pound) in worms daily. They also eat some plant material – seeds, sedges, and ferns. They feed during the day, solo, during breeding season and at night on their winter grounds. Here’s a video of a woodcock foraging https://www.youtube.com/watch?v=swHtEAEfGXM&ab_channel=CornellLabofOrnithology.
The woodcock’s typical rocking walk was explained by early ornithologists as a tactic to produce vibrations that would rouse earthworms into motion so that the woodcock could hear them. Later biologists speculate that the slow gait tells potential predators that the Woodcock knows they’re there (and is in no hurry). See https://whyevolutionistrue.com/2021/02/28/why-do-woodcocks-rock-when-they-rock/ (but don’t turn on the audio).
Any animal that feeds with its head down runs the risk of becoming a meal while having a meal. Over time, woodcock eyes have migrated toward the top of their head. As a result, woodcocks have good vision both in back and to the sides while they probe for worms (as opposed to a robin, which has eyes on each side of its skull and can’t see much to the fore or aft). Because their eyes have thus migrated, their brains have been rearranged and are upside down.
But, they’re famous for something besides their looks.
Woodcocks make their presence known in early spring – often by mid-March – when males take to the air to perform their amazing “sky dance.” They begin around sunset and continue into the wee hours, especially if the moon is full – the BugLady has heard them in her field at 1:00 AM. The dance is repeated at dawn.
After calling from the ground for a while – a nasal sound described as a “peent” https://www.youtube.com/watch?v=4Owj52XhoxI – the male takes off. Specially-shaped wing feathers produce a twittering sound as he spirals into the air, sometimes more than 300 feet up. From high in the sky, he zigzags back down, vocalizing a rich “chirp, chirp, chirp, chirp” sound.
Let Aldo Leopold tell it: “Up and up he goes, the spirals steeper and smaller, the twittering louder and louder, until the performer is only a speck in the sky. Then, without warning, he tumbles like a crippled plane, giving voice in a soft liquid warble that a March bluebird might envy. At a few feet from the ground, he levels off and returns to his peenting ground, usually to the exact spot where the performance began, and there resumes his peenting.”
There, the theory goes, the enamored female woodcock will find him.
Once she finds him, he struts and bows with outstretched wings. Females may make the acquaintance of several males, and vice versa, but by the end of April, the show’s about over. Males will continue their sky dance into early May – even though most of their potentially appreciative audience is sitting on eggs. They are often incubating during the final snowstorms of spring. Hope springs eternal, and some females will join the dance even while they’re caring for young.
Woodcocks nest on the ground; females line a shallow depression with leaves and deposit (usually) four mottled, tan eggs in it. She will sit on them for about three weeks, but the male does no incubation or child care. The young are “precocial,” (think “precocious”) – unlike the blind and naked young of songbirds, woodcock nestlings are dried off and running around within hours of hatching. Although she continues to feed them for a week or so, the young are probing for food when they’re just three or four days old, and flying after two weeks. Fun Fact – newly-hatched Woodcocks have adult-sized feet.
As ground-nesting birds, woodcocks are preyed on by dogs, cats, skunks, possums, and snakes. The BugLady once saw a woodcock fluttering across a field, just above the grass tops, pursued by a raccoon; it may have been a female, leading the raccoon away from her nest.
Many birds undertake epic migrations, but not the Woodcock. As the ground chills and worms migrate vertically to escape the frost, woodcocks need only travel to the Southeastern and Gulf States, where unfrozen ground allows them access to food. Woodcocks migrate at night, at low altitudes, alone or in small groups, usually starting in October. The trip is unhurried, with the birds’ cruising along at about 25 MPH. They start the return trip in February.
Around the beginning of the 20th century, books were being cranked out by “nature-fakers,” who romanticized and anthropomorphized the daily lives of the animals they wrote about. They wrote that a woodcock was able to set its own leg if one got broken – the proof being the crusted mud often seen on woodcocks’ legs.
