January 2008 – Seabrooke Leckie

Mid-winter moth sighting

Speaking of hibernating insects, last night when I went to brush my teeth I discovered this little guy on the wall. The last time I saw a moth was probably back in November; generally speaking they’re not the sort of bug you expect to be out and about in mid-winter. So I was a little surprised to see it. I took some photos but otherwise left it alone. It was gone by the next morning.

I’m relatively new into moths as a group, but I’m fairly certain this one is Agonopterix pulvipennella. Moths are the sort of creatures where they’re either so obviously distinct it’s hard to mix them up with something (for example, a Luna Moth), or so similar to six other species that you really wonder just what criteria was being used in calling them unique. This one falls into the latter category. The key here is the dark spot on the wings, with a little white spot at the bottom, and a broad pale arch that crosses the shoulders and joins the two dark spots. But it takes a bit of scrutiny to identify, and it still looks like a bunch of other Agonopterix species.

A. pulvipennella, it turns out, doesn’t die with the cold weather, like many insects do, but rather overwinters as an adult, and then comes out to breed in the spring. Like the ladybugs and wasps, it will often choose cracks in the walls of your house to crawl into to settle down for the winter. When the weather warms up a little, they can end up in your house. What was funny about this one is that yesterday it was rather nippy out (not helped by the gale-force winds), so I guess it’d come out the day before (when it was nice and mild) and had been hanging around, unseen.

It seems to be a relatively common and widespread species, found throughout much of northeastern North America. The larvae feed on the leaves of goldenrod and nettle during the summer. They pupate in late summer, and adults emerge starting in August. Although the moths are about throughout the fall and into the spring, they’re apparently most commonly seen in the spring, which seems sort of funny to me. Perhaps because, to a moth, UV wavelengths mimic the pheromones of a female, they’re more likely to be attracted to lights, where we can see them, in the spring when looking for a mate?

A visit from the queen

The temperature today was an incredibly balmy 8 degrees Celsius. This was a one-off, however, because a cold front is supposed to roll in tonight and tomorrow is forecasted to be -10 oC (I shouldn’t complain; today in the Canadian prairies it was -50. Before windchill). Still, the warm weather was nice. I wasn’t the only one to think so. This afternoon I found a wasp crawling, somewhat sluggishly, along the windowsill in the den.

In my very first post I talked about the appearance of ladybugs mid-winter. Wasps are very similar visitors. They crawl in to cracks in the walls of the house in the fall when looking for hibernation spots to spend the winter. Normally they would only come out when the warmer spring weather finally arrives, but warm spells can cause a few to come out prematurely. Those that chose to hibernate in your house will quite often go the “wrong” way, toward the warmer temperatures inside, and end up crawling along your floor or windowsill.

Wasps are like honeybees, in that most species spend the majority of their year living in colonies. There’s a queen who “rules” the colony, although her primary job is simply laying eggs. There are sterile worker wasps, who spend their time collecting food for the young grubs and the queen (and themselves), repairing and defending the nest. And there are fertile male wasps, whose only job is to mate with new queens.

In the spring, a new queen, who mated with a male before going into hibernation in the fall and stored the sperm inside her, will pick a site for the nest and start a new colony. Depending on the species, she may start it alone, or with a few of her sisters who overwintered with her. She lays fertilized eggs, which develop into sterile female workers. She’ll care for the first couple of broods herself, but once there are enough workers to tend to the eggs and larvae properly, she concentrates on just laying more eggs. Once the sperm runs out, in mid- to late summer, the unfertilized eggs grow into fertile males and new fertile queens, who go out and mate, and start the cycle again. The wasps that turn up in your house in the middle of winter are all young mated females who have gone into hibernation till the spring. All the other groups – the original queen, the sterile workers and the males – died once the weather turned cold (if not before).

These mated females are stingless. The initial reaction upon seeing a wasp, particularly if you have kids or pets, is to worry about someone getting stung. However, the stinger in wasps and bees is a modified ovipositor (the body part used to lay eggs). Males don’t have an ovipositor to begin with, and mated females need theirs to lay their eggs come spring. Only the sterile worker females have the ability to sting. I suppose she could give you a good chomp with those powerful jaws (look at the size of them in that first photo!), but it’s unlikely to feel like more than a pinch. Paper wasps use their jaws to strip bits of wood from logs or dead trees, which they then mix with saliva to create the “paper” used in building their grey papery nests. If you spend a lot of time on your deck in the summer, you might catch one collecting wood from the deck or siding.

Wasps are generally predatory, preying on other insects, although they can sometimes be seen feeding on the nectar of flowers. The particular composition of their diet depends on the species. They’re useful to have around your yard because they’ll take care of many other undesirable bugs in your garden or around your home. As long as you don’t actively disturb their nest, or pester an individual (intentionally or not), they’re generally fairly docile, willing to let you do your thing while they do theirs. If it’s a mild day when you come across a wasp in your house, let her crawl onto a piece of paper and then transport her outside, where she can find herself a new hibernation spot, and she’ll take care of your garden for you come spring.

Colour-coding chickadees

Edit: This post was recently included in the 69th edition of I and the Bird, a blog carnival focusing on, you guessed it, birds. You can check out the full edition at Living the Scientific Life.

Yesterday afternoon Blackburnian and I went out birding in a tract of woods near Paris, Ontario. It wasn’t a large patch, but was still perhaps 8 or 10 acres, and we spent some time wandering through it. There was very little activity in most of it, which is typical of woodlands in the winter. Although in spring and early summer the woods can be alive with birdsong, once the migrants depart in the fall there are very few birds left that favour that sort of habitat. Woodpeckers, chickadees in small flocks, perhaps the odd tree sparrow or junco in the scrubby bits if you’re lucky. But pretty quiet.

The best places to see birds in the winter is near a feeder, which is part of the reason I don’t do a lot of birding in the wintertime – when all the birds are coming to you, where you can view them from the comfort of your home, why go out into the cold to wander around an empty woodland? Of course, there’s lots else to see in the woods, but I usually reserve those outings for warmer days with lovely weather. The place we were at yesterday had a section of boardwalk where a few feeders had been set up, and kept regularly stocked. Although they were visited predominantly by Black-capped Chickadees, there were also Dark-eyed Juncos, American Tree Sparrows, Northern Cardinals and both Red- and White-breasted Nuthatches visiting them.

Like at a lot of parks with bird-feeding trails, the chickadees and nuthatches had learned to come to people’s outstretched hands to pick up seed. This is an absolute delight for small children, and even for adults there’s some magic in a wild creature coming to your hand with enough trust to take a bite of food. Although we hadn’t thought to bring any seed with us, we borrowed a few seeds from one of the feeders and offered them to the chickadees. And the chickadees were quite happy to take them.

Just nearby is Wrigley Corners Outdoor Education Centre. As part of their education and research programs, they have been banding the chickadees that come to the feeders here in the park. They use a combination of bands, both silver aluminum and coloured plastic ones, to create a unique colour combination that can be easily visually identified at a distance. This allows you to follow individual birds to learn more about their behaviour patterns and movements. No two birds in a study are ever given the same band combination, unless it’s known the previous owner of a combination is deceased. Band colours are read from top to bottom, with the bird’s left leg first, then the right. So the bird at the top of this post would be Red-Orange:Silver-Green. The above bird would be Silver-Pink:Blue-Blue.

Here Silver-Red:Yellow-Yellow surveys the proffered seeds before coming down. The bands circle the bird’s leg much the way you or I would wear a watch, or a bracelet; they aren’t attached to the bird’s body, and they cause it no discomfort or inconvenience. Although it takes the bird a few minutes to get used to this new addition, it quickly moves on with foraging for food, or whatever else is on its daily agenda, and isn’t bothered by it again.

And, as you can tell by these birds still coming to peoples’ hands, the process of having the band put on hasn’t caused them any real distress. Most birds are banded and measured, and then safely released within a minute or two. In addition to the coloured bands, the silver band has a 9-digit number that also uniquely identifies the bird in a national database, should it ever decide to wander and someone else encounters it. This number is also useful for identifying birds without colour bands if they’re captured again (it’s too small to read from afar on most birds), and particularly for migrant birds that may turn up somewhere else on the continent.

Colour bands are most often used on studies of birds on territory; that is, birds that aren’t moving around a lot. By banding the breeding birds of a particular species in a forest plot, say, you can track how many individuals there are, who owns what territory, what males are mating with what females, how far birds are foraging from their nests, and other interesting and valuable information. The data collected from such projects is used in making decisions about conservation practices to protect the birds and the habitats they live in. Similar studies take place with birds on their wintering grounds. Even though we didn’t spend a lot of time with them yesterday, we were still able to make some observations, such with as the above bird, Red-Orange:Silver-Green. In the above photo, s/he (both sexes look the same) was about 20 metres down the trail from where the first photo of the post was taken. Ordinarily I would probably have thought they were a completely different set of birds, but obviously they were moving around the area – seeing if other peoples’ offerings were any better, I guess!

Frost feathers

Yesterday morning when I got up there was frost on the windows in the den. Only the den, for some strange reason; even the neighbouring washroom’s window was frost-free. I would attribute the frost to the old, single-pane windows of the farmhouse, but other rooms have the same windows. Even stranger, the two windows had completely different frost patterns.

What causes frost patterns? Frost is ice, and like ice is simply a freezing of water molecules. The patterns are a result of the environment the molecules are in when they freeze. Usually there needs to be some sort of catalyst, like a mote of dust or a grain of pollen. The water molecules in the air affix to this catalyst, and then other water molecules that bump into it affix to them. As the crystal grows, the likelihood of other molecules encountering it, and attaching to it, increases, in a positive feedback loop.

Snowflakes that begin on a catalyst are generally (though not always) non-symmetrical in shape. Occasionally water molecules will get together without a catalyst (not nearly as common as it takes some great coincidence for so many molecules to be at the same place at the same time), and, because of the way a water molecule is shaped and bonds, end up with six in a hexagon. Because the points of the hexagon stick out further than the sides, the new molecules affix there, creating the stereotypical six-pointed snowflakes.

In the top photo it looks like the initial catalyst were strings of spider silk that had probably been blown from the plants in the garden onto the window back in the fall (given that spiders haven’t been particularly active lately). The frost was formed in strings that looped across the window in a neat criss-crossing pattern.

Frost is beautifully intricate close-up. You can see the typical feathery shapes branching off the linear spider-silk catalyst lines here. The specific patterns of the feathery growths from the catalysts depends on numerous factors including, but not limited to, air pressure, air temperature, surface temperature, humidity, and even imperfections of the surface. These old windows are certainly anything but perfect! It looks like many of the feathers are also growing from the outer curve of the line, where the molecules would be more exposed.

On the other window, Although there were some lines through the pattern, it wasn’t the same sort of criss-crossing. Instead, it was more of a flowery blanket of round feathering. I suspect the pattern on this window was more dependent on dirt or glass imperfections for determining the pattern of crystal growth, with the exception perhaps of a few strands of silk creating the lines. As to the reason that only the southeast corner of the house had frost on the windows, I can only hypothesize. Perhaps there was a south wind blowing that chilled those windows more than others? It was a particularly windy day, though I neglected to note the direction. It may remain a mystery.

One amongst the redpolls

I had the coolest experience today. Just after lunch, I took a break from scraping old caulking off the sides of the bathtub in the washroom my parents are renovating to wander outside with a new close-up lens (really more like a filter, or a magnifying glass) I picked up today for my camera. I was excited about the new lens and wanted to test it out, so I pulled on my toque and mitts and cozy down jacket and stepped out to brave the -8oC weather.

I started out by going around to the back garden, looking for seedheads or other interesting things to photograph. I paused to take a picture of an old vine flower that resembled a daddy-longlegs with too many limbs, then another of a coneflower with a tophat of snow. As I was standing there a handful of Common Redpolls flew into the crabapple tree on the far side of the garden, clearly intending to come down to the feeders once the coast was clear.

How many birds can you count?

They looked pretty perched in the bare branches, set against the dark green of the spruce trees behind, so I took the filter off the front of the camera and started taking a few shots. And then, as I stood there, a few more swooped in, and then a few more, and then in a chittering flurry of wings the whole flock swooped down to the nyjer feeders, not six feet away from me.

I stood stock-still. The redpolls were a little jumpy, and every minute or two they’d all take off again with a swoosh to perch in the branches of the crabapple. They’d stay there for about 20 or 30 seconds, and then come back down when they felt sure whatever perceived threat wasn’t actually. They were so close, I actually had to zoom out to get all the birds in the flock into the frame.

Redpolls are a very pushy bunch. They squabble over perches at the feeders, often chasing each other off when there aren’t enough perches to go around. With this flock there were probably about 60 birds who had to share two 8-perch nyjer feeders. Most of the birds ended up on the ground under the feeders searching the hull litter for seeds, but a lucky few had the luxury of sitting beside a constant supply of unhulled seeds.

They’ll even turn upside down on their perches to snap at their neighbour if they feel he’s getting too close.

And they’re not afraid to physically push somebody off if they feel they can get away with it.

There were a few birds in the flock that stood out as unusual. A number of adult males, with their gorgeous rosy-pink breasts, were in the flock, but this one in particular caught my eye. A real uber-male, with a deep rosy wash through most of his feathers and even rosy on his rump, where most adult males are simply pale. I think this male might be of the “Greenland” subspecies (they breed on Greenland and a couple of the northern Canadian islands), rather than the usual “mainland” subspecies. The Greenland birds are on the whole larger, browner and stockier. And possibly rosier in adult males, too, from the looks of this bird. There were a few Greenland birds in the flock, but this was the only adult male I noticed.

Many of the characteristics of the below bird lead me to think it may be a Hoary Redpoll, a very closely related species to the Common. Hoaries tend to breed a little further north, although their range overlaps, and both species are far north relative to here. Hoaries average paler (can be subtle in first-winter birds), with thinner streaking, fewer markings on the undertail coverts and rump, and a shorter, stubbier bill. This one has all the markings except the bill isn’t noticably stubby (a good side-by-side comparison is shown here).

I stood out there among the redpolls for perhaps 20 minutes, watching them squabble, and come and go, and come again. I was there long enough for my legs and fingers to start to go numb (but my upper body was nice and toasty in the wonderful down jacket I got for Christmas). I was there long enough for the redpolls to start to ignore my casual movements. I could turn to look from one feeder to the other without flushing them, or shift my weight from one foot to the other, shuffle to reorient my body, lift my camera to my eye. In fact, I was buzzed a couple times, and one bird even perched for two or three seconds on the hand holding my camera to my face, before flying over to try for a perch. It was only three or four inches from my eye! I was reluctant to go back in, but in the interest of avoiding frostbite, and because there was still lots of work to be done indoors, I waited for the flock to return to the trees and then slowly turned and headed back inside.