August 2009 – Page 3 – Seabrooke Leckie

Tay Meadows Tidbit – Tree cricket

Edit: I actually wrote this last night, but apparently when I hit “Publish”, WordPress didn’t actually publish it, or something went wrong, or I hit the wrong button but thought I’d hit the right one… who knows. Here it is now, in any case.

I’ve been having some technical difficulties with my camera the last couple of days, and as I sort them out I’ve been relying on photos I’ve already got on my hard drive. Fortunately, there are plenty, some 30,000 image files, in fact (I think I should be back to shooting new stuff again tomorrow anyway, though). Today’s photo is actually going waaaay back. I took these pictures last October, while visiting my parents’ old house for Thanksgiving. I found this intriguing insect sitting on the railing of the front entry porch.

When most of us think of crickets, what probably come to mind are field crickets, those chunky-bodied black insects that we’ll often see in the lawn or gardens. A few reptile owners might think of the brown sort you buy from the pet store, which are called house crickets. However, there are some 115 cricket species to be found in North America, in 25 genera. These encompass a broad range of shapes and sizes. Crickets share the thick, strong hind legs and long antennae with their cousins the grasshoppers and katydids. They can be told apart from these other two groups by a pair of long, thin tail projections extending from the rear of the abdomen.

Tree crickets are a very slender group compared to most other crickets, and more resemble grasshoppers than crickets. They belong to the genus Oecanthus, and most members are primarily identified based on the pattern of black markings at the base of their antennae. I neglected to get a good photo of the face of this one, but did find one that showed the base of the antenna, and cropped it in closely. Based on this photo, I believe this to be a Narrow-winged Tree Cricket, Oecanthus niveus, which have J-shaped lower markings. They hatch in early summer, and are grown and mate in the fall. It’s possible this one was out looking for a partner.

My Kaufman Insects guide indicates that Nathaniel Hawthorne wrote about the song of tree crickets that “If moonlight could be heard, it would sound like that.” Rather than the repetitious “chirp chirp chirp” that we think of as filler in uncomfortable silences, tree crickets sing in long trills. You can hear a male of this species at this YouTube video (links to YouTubes of other species are there as well).

Females can be told apart from males by their long, thick ovipositor. This one is a female. I’m not certain what she’s doing in this photo; she bent her abdomen forward underneath her and appeared to be cleaning it. You can see her two “tail” projections folded against the ground underneath her.

Typically, tree crickets eat aphids and other soft insects, though they’ll occasionally forage on fruits and foliage. It appears that most of their leaf-munching is tied to creating song posts from which the males sing to females. They cut a small hole in the leaf, and sit in it while they call, I guess using the leaf as a parabola.

You can read a bit more about the life history of tree crickets at the website http://oecanthinae.com/ – the tree crickets have their own web domain even!

White-blooded plants

The part of the meadow immediately around our house is filled with Common Milkweed, Asclepias syriaca. I don’t think I’ve ever seen such a large patch of milkweed before. Ordinarily I would find single plants, maybe a few loosely clustered together, but I’d never found any area where they were the dominant wildflower. They’re a plant, like lilacs in the spring, that I love to walk among because of the heady sweet fragrance that rises from their blossoms. Such an incredibly large patch gives off an incredibly delightful scent. The smell is likely a byproduct of the plant’s nectar-rich flowers, which have an unusually high proportion of sugar in their nectar. Native Americans would actually use it as a sweetener, like honey, though I can’t imagine how painstaking it must have been to harvest.

There are more than 140 species in the genus Asclepias, the milkweeds. Around here we only have a handful, of which the Common Milkweed is probably the most common and well-known. Others include Swamp Milkweed, A. incarnata, and Butterfly Weed, A. tuberosa. Butterfly Weed isn’t that common, but it’s certainly eye-catching, with vibrant bright-orange flowers that, as the name implies, are especially attractive to butterflies and other insects. Asclepias are also known as Butterfly Flower and many cultivars can be commonly found in nurseries and garden centres.

The name milkweed, of course, comes from the white sap that oozes from the plant’s veins when its leaves or stem are broken. The sap contains a type of latex, similar to that collected from rubber trees, but for which attempts to process it have been largely unsuccessful. The actual function the latex serves to the plant is still up for debate, although it may be either an additional defense against predators due to its bitter nature, or possibly a coagulating agent in cases of wounds. Anyone who has broken a milkweed leaf knows how sticky the sap is.

The plant can also be harvested for silk fiber, which is taken from the downy seed puffs in the fall and winter, as well as bast fiber, which is the stringy inner “bark” of the plant. The latter much resembles hemp in its properties and uses. Interestingly, oil from the seeds can be converted and used as a very effective sunscreen. Even though at maturity the plant is toxic and could make you ill if eaten, these toxins are found in minimal quantities when the plant is young, and can be destroyed through cooking, allowing young leaves and sprouts to be consumed.

The vast majority of Common Milkweed flowers are purple – either a dark purple, as in the previous photo, or a lighter purple as shown in the foreground of the second photo. However, while out walking with Raven one afternoon I came across three plants, all clustered together, that had peachy-orange flowers. I can’t find any mention of this unusual colour online. At first I just assumed they were older, but they were still in good shape, and fading flowers typically go yellowish-white, rather than peachy-orange. I’d be curious to know if anyone else has observed this colour morph.

I suspect that milkweed is probably best known for its role as a host plant for monarch butterfly caterpillars. I have seen a few monarchs in our patch this summer, but I’m not sure whether the rain has affected numbers or they’re just not as common around here, as there haven’t been nearly as many as I would expect for a patch this size. I’ve been watching for caterpillars, but haven’t spotted any yet.

Monarchs aren’t the only insect that milkweed appeals to. Ants are attracted to the sweet nectar of the flowers, and many of the plants I looked at had ants crawling all over their flowers.

These Red Milkweed Beetles, Tetraopes tetrophthalmus were recently emerged and crawling about the milkweed plants. They were fairly abundant, with many plants hiding at least a couple. Classified with the long-horned beetles, this species uses the milkweed as a host plant, much like the monarchs. Their larvae bore into the stems of the plant, feeding on the plant tissue there, and then overwinter in the roots. They emerge as adults in the early summer to mate and lay eggs. These two, and many of the others I saw, may have been crawling around looking for a mate. Most species that feed on the plants as larvae end up being either toxic or distasteful (or both) to potential predators, and sport bright warning (aposomatic) colouration. In the case of these beetles, it’s a bright red with black spots.

This one is an Orange-spotted Lady Beetle, Brachiacantha ursina, a native species that is often associated with milkweed. I’m not sure whether its larvae likewise use it as a host plant, or if the adults are there for another reason. I saw several of these guys on the plants when I poked around looking to see what I could find.

This final species is Three-banded Lady Beetle, Coccinella trifasciata, another native. There appear to be two subspecies, one that occurs across most of the continent east of the Rockies (C. t. perplexa), and the other that is found west of the Rockies, along the coast.

The Large Milkweed Bug, Oncopeltus fasciatus, is another species I’ve recently been seeing a number of on the plants, but for whatever reason I don’t seem to have taken a photo of them at any point.

Tay Meadows Tidbit – Crayfish

We had our last MAPS session at Rock Ridge this morning. It was quite productive, our second-busiest morning there, with quite a number of dispersing young birds. Dan will likely write more about the birds in the next few days.

On our way out, as we were preparing to launch the canoe and paddle back to the car, I noticed a couple of small crayfish in the water just along the shore. They were only about two inches (5 cm) long or so, fairly small by crayfish standards, but were intriguingly washed with blue, and had red rings around their elbows.

I wanted to get a photo up close, but, perhaps due to my double-X genes, was reluctant to stick my hand near those pincers, despite Dan’s attempts at reassurance that even if they did pinch they were too weak to hurt. Dan tried crawling to the front of the canoe to catch one for me, but without any luck. They crayfish continued to sit in the leafy debris at the edge of the shore, so I plucked up the courage to try again; I was able to grab it with a quick snatch at the mud. However, startled that I’d actually succeeded, I reflexively tossed the handful of mud toward the open floor of the canoe – which was also where Dan was sitting. Fortunately, he and the crayfish were both fine.

Upon coming home and browsing the net, I discovered the website CrayfishOntario.ca, which seems to be a site/project set up with the goal of helping increase awareness of Ontario crayfish. It’s a joint project between the Toronto Zoo, Ontario Nature, and Bishops Mills Natural History Centre. There are 10 species of crayfish listed on their brochure, of which all but two are native. However, like so many non-native and invasive species, the two exceptions are causing some problems among native populations. Habitat loss and pollution are also contributing to the decline of some of our native species. However, even in areas where neither of these appear to be a factor, crayfish have disappeared from some lakes. The cause is unknown – disease? competition? pH changes? – and their brochure simply lumps these disappearances under “other mysterious causes”.

After studying their guide, I think this is a Northern Clearwater Crayfish, Orconectes propinquus. They indicate that one of the distinguishing characteristics of this species is the orange tips to the claws, which this one shows. It’s a native species, found through most of northeastern North America. It seems to be a bit of a generalist in the habitats it uses.

I wrote about crayfish last spring; for more on their general ecology and natural history, you can check out the original post.

A girl’s best friend is her horse

I spent the evening at my sister’s place today, to try to take some portrait photos of her with her horse. I didn’t quite achieve what I was looking for with the batch we got this evening, and I suspect I’ll be making another trip there.

I had planned to do up a post on milkweed this evening, but I got in later than expected, and am rather tired. So, in a tribute to (mostly) Wordless Wednesday, here are a few of my favourites of the 210 exposures, even though they’re not really nature-themed.

Tuesday Miscellany

The month of July has been one thing after another, it seems, and I’m not just talking about nature observations. Between moving at the start of the month, internet downtime immediately following the move that stretched into a few weeks, unpacking and settling into the new home, housesitting for my parents a couple of times, and a trip back to Halton for a funeral, I’ve had lots of distractions that have kept my mind from blog. As a result, I have a pile of photos that I’ve taken but not posted that I thought I’d gather together and put into a miscellany post.

The first photo is from a couple of weeks ago. I’d taken Raven for a walk at the 100 acres that adjoin our main piece of property, to scout out the trails and get the lay of the land. As I was following the path through a field lined with milkweed, I spotted this little guy curled up in the leaf of one of the milkweed plants. It was a smaller Gray Treefrog than I usually see, and the facial markings were particularly well-defined. I wrote about treefrogs last spring when I found one calling from my parents’ water garden.

Another amphibian, this one an American Toad. This guy turned up at one of our MAPS stations. I’d just taken off my rainpants (which I consider a vital piece of clothing in the early morning hours when everything is still covered in dew) and had sat back down on the rock when I was startled to discover a toad only a couple of inches from where I’d just flopped down. I’d missed squishing him by less than a hand’s breadth. You can read more on toads from a post I did last fall.

Another near miss, this Eastern Milksnake was sunning itself on a patch of moss when I very nearly stepped on it. It may even have been the same day. I haven’t seen too many milksnakes about; even though they’re common, they’re not frequently encountered, being less numerous I guess than the abundant garter snakes. I’ve done a post on milksnakes, too. It happens to be my number one top most visited post that I’ve written so far, no doubt because they are often kept as pets.

I found this caterpillar in the grass at Rock Ridge a couple of visits ago. It stayed in the same spot for half the morning. It was a fairly chunky caterpillar, as these things go, and being brightly coloured I figured it would be easy to look up when I got home. I searched through all of my caterpillar references, and then did a Google image search for yellow caterpillars, and wasn’t able to find it. So I turned to my usual fallback, BugGuide.net. Within hours of posting the photo, it was identified for me as an Elm Sawfly – not a lepidoptera at all! Which would explain why it wasn’t in my caterpillar books. (It is actually in the Kaufman insect guide, but looks white there, not yellow, so I may not have noticed it). Sawflies are actually a type of stingless wasp that deposit their eggs in the twigs or leaves of plants. The “saw” in their name refers to the structure of the ovipositor, which resembles a saw.

This one really is a caterpillar. I believe that it’s a species of moth in the genus Furcula. However, when you look at caterpillar guides or online at BugGuide.net, all of the Furcula caterpillars are green with brownish saddle patches. None are completely brown. A Google image search turned up only one other brown Furcula caterpillar, which was taken by Bev of Burning Silo, who happened to have taken the photo just up the road (relatively speaking) from mine.

I found this nifty fly resting on a dried flower head among the patch of sunflowers when I was searching for insects. It didn’t move when I plucked the deadhead and twisted it around for a better photo. I wondered if it might be dead or possibly parasitized, but when I put the stem back down and it brushed against a leaf the fly took off. It’s a Tachinid fly, possibly in the genus Cylindromyia. Tachinid flies are nearly all internal parasitoids of caterpillars and other insects. Whereas parasites will feed off their host but let them live, parasitoids nearly always kill their host in the end. You can really see well the “halteres”, the vestiges of the second set of wings, which look like round knobs behind the main wings here.

In banding you often have the opportunity to see some strange things you may not have noticed or been able to observe while the bird was perched up in a tree. This is one of those things. This bird’s foot has been infected with a type of bird pox that gets under the scales of the foot and causes mutated growth of the cells. This one is an especially “hairy” looking one, many just grow thick and lumpy. These growths are especially tender and prone to bleeding if they get caught up in netting or the like, and you can just imagine how uncomfortable they must be for the poor birds. I let this guy go as soon as I’d removed him from the net, without taking him back for processing. Occasionally the pox can spread up their leg, and if it does it can become a nasty situation, causing the normally loose bracelet-like band to squeeze and constrict the leg. Some birds will never suffer that, but better safe than sorry.

The new home has many bluebird boxes scattered out in the meadows behind the house. When I was walking through the meadows near one of these last week I could hear constant chittering coming from one of the boxes. As I drew nearer, I could see faces frequently popping up to the hole to peek out at the world. Clearly these were fledglings that would be departing the nest either later that day or the next. They had lots to say, and weren’t too concerned about me. however, when Raven came near to the box, panting loudly and conspicuously, they all shut up and sat tight. Too late, little birdies, you’ve already given away your location!

And finally, this box belonged to some actual bluebirds. Dan discovered the nest, tipped off by a couple of upset adults when he walked by the general vicinity of one of the boxes. Very young, only a few days old at most, these babies are most likely a second brood for the bluebirds. Baby birds grow fast to begin with, but second broods are especially fast, and these babies were probably out of the nest by a week and a half old, two at the most. The boxes that are currently in place are old, weathered, and some are starting to rot. Also, they all require a screwdriver to open. Dan and I will probably replace a few over the winter/spring with new ones that can just be flipped open to check and clean. They’re all currently above head height, too – hard to see what’s inside without a stepstool! I got this photo by holding the camera above my head and hoping for the best.