Month: July 2021

Do leeches make your flesh crawl ? Rather like snakes, many of us recoil from these blood-sucking worm-related creatures. If that is your reaction, either stop reading now or, ideally, read on and learn to overcome your distaste.

Today I have two different leeches to show you.

This is a North American Turtle Leech, Placobdella parasitica. The scientific name placobdella comes from the Ancient Greek roots plac- and -bdella, meaning plate-leech.

They spend most of their lives on freshwater turtles, without appearing to harm the turtle. Like most leeches, they are hermaphrodites, possessing both male and female reproductive organs. One leech deposits a spermatophore , or sperm package, on the back of another, and the sperm are able to penetrate the skin and reach the uterus in the recipient leech. These particular leeches also rear their young, which blew my mind. Follow this link for more detail and great photos:

Smooth Turtle Leeches

The other day I joined a Greater Lovell Land Trust group led by the wonderful Nat Wheelwright specifically to look for leeches (yes, I know that is a rather niche activity). We were especially hoping to find the medicinal leech, Macrobdella decora. The first part of the Greek name is a clue: it is BIG.

Nat Wheelwright and I waded into the muddy edge of the pond up to our knees, and chatted while we waited to be found. Nothing. Nat got out, I stayed. And a few minutes later…. (Thanks to Leigh Macmillan Hayes for the photo.)

Like most leeches, it can transform its shape from long and thin to short and fat. At its most elongated, it was about 4 inches long. It made no attempt to latch onto me (thank God), and Nat explained that they only feed on amphibians, fish and turtles, whose body have a sort of algae or slime that seems to attract them. My legs are blessedly not slimy enough.

After some failures, he managed to catch it in his net while I stood very still, and we got a good look at it.

It is a dark olive black, with a line of red dots along its back. The head (and mouth!) is on the right, and the tail ends in large sucker with which it anchors itself. Its belly is a bright orange:

In true Indiana Jones style, here is Nat with the leech:

He did remove it before it crawled into his ear.

In the 18th and 19th centuries, these are the leeches that doctors used to “cure” a multitude of ailments, including fevers, hemorrhoids, and pregnancy! Leech farms sprang up to serve the lucrative market. There is a great potted history of the practice here: https://www.sciencehistory.org/distillations/medicinal-leeches-and-where-to-find-them

But it turns out there really was a benefit to some of this. Leech saliva contains an anti-coagulant, and so it can reduce inflammation in a very localized area. They are now used again in microsurgery and plastic surgery, and there is a thriving high-tech leech farm in Wales!

* My title comes from the quote below. (Finding good leech quotes is not easy! They are pretty much all derogatory.)

“If leeches ate peaches instead of my blood, then I would be free to drink tea in the mud.” Emilie Autumn

“The leech’s kiss, the squid’s embrace, The prurient ape’s defiling touch: And do you like the human race? No, not much.” Aldous Huxley.

Wood ducks start nesting in mid-April. Incubation is 28-37 days, meaning the first ducklings arrive from mid-May onwards, and I saw two different sets of ducklings this year on June 2, one lot freshly hatched and one lot older. They are elusive, but I see them from time to time, rather surprisingly often eating spatterdock, which seems to be a favorite food*. Here’s one on June 19th:

The next photo shows a mother with two month-old youngsters whose adult plumage is now pushing out their childish down. She has waited till July 14th when the spatterdock flower is over and the ovary is exposed, and carries off her trophy.

From hatching to flying is about 60 days, so the oldest batch can just about fly now, July 14th. But breeding season is not over! Yesterday, I saw a mother with seven brand new ducklings, each about 5″ long.

She could be a late starter, or it could be her second brood, perhaps after losing her first lot to predators. Her second brood is being given a safety lecture:

Mid-July is just about the latest date for a successful hatch, and round here second broods are rare, less than 1% of females (they are more common further south).

PS: Aging the ducklings is difficult. here is a description of their plumage, from Birds of the World. “Development of Juvenile plumage in wild birds in Massachusetts (Grice and Rogers 1965): downy pattern fading and first rectrices appearing at 20 d; wing coverts emerging and feathers on breast and belly visible at 30 d; primaries breaking from sheaths and crown feathers visible at 40 d; white cheek marks visible on males and underparts completely feathered at 45 d; body feathers complete except on back at 55 d; many birds (70%) able to fly and eye of males turning red at 60 d; most birds flying and Juvenile plumage almost complete at 70 d. Young birds are able to fly at 8–10 wk”

*Martin and Uhler (1939) say that while Spatterdock seeds have been found in the stomachs of some ducks, they are not a major food. Hepp and Bellrose (2020) do not list it at all as a Wood Duck food. Maybe the ducklings are just playing? But the adult photo makes that unlikely.

[Oops, I hadn’t meant to send this yet, but I hit publish by mistake!]

I’ve never heard of sawflies, and now I have seen two different ones, and the larva (caterpillar) of another. Just plain luck. (I do realize some of you probably think I am a little eccentric to get excited about a fly.)

Sawflies are in the order Hymenoptera together with ants, bees, and wasps. All of these insects have two pairs of wings, unlike true flies, Diptera, which only have one pair of wings. You can clearly see the four wings in this photo. So they aren’t actually flies at all. They have a saw-shaped ovipositor, hence the first part of their name, but they are nearly all harmless plant eaters.

They have a life cycle with four stages, eggs, larva, pupa, and adult, and the adults only live for about 8 days, which maybe why I haven’t often seen them! These next two photos show the larva of the North Americans Sawfly in the photo above:

Here are the larva and the adult of one called, I think, Monostegia abdominalis.

The larva often congregate in large groups to feed, and rear up when startled. I’m not sure which species this is, but they are sawflies, not caterpillars, because they have a pair of prolegs on every segment, and no claws on the prolegs:

I found a surpassingly ugly caterpillar the other day.

It took me a while to identify it, and even longer to understand the significance of what I was looking at. This unappealing grub transforms into more than one possible butterfly, in a twist on one of nature’s greatest mysteries that has become a famous evolutionary case study.

Round where I live in Maine, the caterpillar is likely to metamorphose into this (photographed last year):

This is a White Admiral, Limenitis arthemis arthemis. Notice the red spots and the blue scalloped border. But go a little further south, and it becomes the Red-spotted Purple, Limenitis arthemis astanyax, totally lacking the broad white wing bands.(photo from Wikipedia)

The southern form mimics the blue hindwing coloring of the very toxic Pipevine Swallowtail, Battus philenor, and their two ranges coincide. This “Batesian mimicry” deters predators. DNA evidence shows that the two colorations hybridize across a zone starting in southern New England, shown below in dark grey (from Ries and Mullen 2008)

Interestingly, the presence of even small numbers of the toxic model in the hybrid zone is enough to maintain some instances of the mimicking coloration. Only when there are absolutely no toxic models present, as in Maine, do the butterflies revert entirely to the non-mimicking coloration. The data are a wonderful example of the importance of citizen science, since they were all taken from the annual North American Butterfly Association’s July 4th Butterfly Surveys going back to 1975. If you’d like to take part in a count, click here for details: https://www.naba.org/butter_counts.html

The really challenging question is how lepidopterists decide whether these two wildly different wing patterns should now count as two species. Although they look entirely different, they can nonetheless interbreed and produce fertile offspring (hence the hybrids), so they are not genetically isolated from each other. *

The controversy continues.

*It reminds me somewhat of dogs. These two animals, a mastiff and a Yorkie, are both of the species Canis familiaris. Cross-breeding to produce a hybrid might be mechanically challenging, but the resulting Yorktiffs would no doubt become the height of fashion.

At this time of year, the trees are in leaf, casting deep shade, so the woodland wildflowers are mostly over. But the ones on the edges of our shrubby, swampy ponds get water and sunlight, and are flowering now. I thought I’d show you some of them, starting with the smallest blooms. No dramatic stories, just modest beauties in hidden places. Let us take our pleasures where we can.

Horned bladderwort , Utricularia cornuta , 1/4″ grows either in the shallow water, or on the muddy foreshore.

The “horn” is at the base of the flower, easier to see in the next photo.

High Bush Blueberry, Vaccinium corymbosum, 1/4-1/2″, is a tall bush that grows at the shoreline, producing its famous berries in late summer:

Sheep Laurel or Bog Laurel, Kalmia angustifolia, 1/3-1/2″, a relative of the better known Mountain Laurel, forms sizable clumps on the waterline:

Close to, the flowers form a tiny posy:

Rose Pogonia, Pogionia ophioglossoides, 1 3/4″, likes somewhat different boggy habitat. It is an orchid, and these were amongst reeds and grasses, hard to photograph from my kayak:

My last flower is the dramatic bizarre flower of the carnivorous Northern Pitcher Plant, Sarracenea purpurea, a sizable 2″ across. It also is found in swampy sphagnum bogs.

When it has been pollinated, the enormous ovary in the center swells up into a bumpy scaly peach-like globe:

Doesn’t it remind you of Little Shop of Horrors?

PS: A couple of these plants were mentioned in 2019 in a post on carnivorous plants, if you want to see the gory details of how they eat: https://eyesonthewild.blog/2019/08/08/marmite-for-plants/

PPS: I rather like this page: https://abogslife.com/2017/06/11/peatlands-and-poetry/