birds – Page 31 – Seabrooke Leckie

Birds on the rail line

A couple years ago (has it been that long already?) I did some bird surveys for the City of Toronto as part of an assessment and preliminary monitoring scheme for a park in the Don Valley. They’ve recently contacted me again, looking to see whether I would be available to do another set for a different site. They’re just looking for an inventory of the bird species found using the site, which doesn’t require lengthy or involved surveys, so I said I’d take them on. I’m just going to be doing area searches, once a week, from now through June, to get a basic idea of what can be found there.

Today I met the woman from the City who I’ve been corresponding about it with, at the actual site. The site is located in the southern Don Valley, only about a five minute drive from my home. I’m surprised not to have known about it, but I don’t drive that way ever. It’s actually a capped and regenerating landfill, a couple decades old, now used as a natural area for outdoor recreation. We walked into it briefly and scoped it out. She answered a few of my questions, I answered a few of hers. We didn’t spend too long there; since it’s not a very complicated project, there wasn’t a lot to be worked out. Once we wrapped up there, I grabbed my camera gear and walked back in, along a different trail, to see what I could see.

I happened across these train tracks. They obviously hadn’t been used in some time; the rails were all rusty, and there were plants growing up between the ties, right next to the steel. I decided to wander along their length a short ways; it had the advantage of not being used by the many other park users, and I had no worry about a train coming along to flatten me.

Especially in the city, rail lines make really great green corridors by which wildlife can move from one area to another. Very rarely does the city come right up to their edge, usually there’s a green buffer of trees and other vegetation that borders each side of the tracks. Although it wasn’t the case here, oftentimes that’s the largest contiguous stretch of habitat within a neighbourhood. As a result, it usually has lots of creatures living in it.

One of the first birds I noticed upon stepping out on the tracks was a male American Redstart. He was singing his heart out from a Manitoba Maple that overhung the ditch on the other side of the rails. Although redstarts can have somewhat variable songs, their most characteristic and distinctive songs is a slightly rising warble ended with a downward buzzy-ish note sounding something like a sneeze.

I started pishing to try to call them forward to the front of the tree. Pishing is a birder’s term used in reference to a sound rather like “pishpishpishpishpish”, said very rapidly. Many birds will become curious or agitated by the sound and come in to check it out. The theory is that it resembles the distress call of another species, in particular the Tufted Titmouse. When members of the tit family start giving their alarm calls like this, it’s usually a call to other species to come help – “Danger! Here! Mob it, mob it!” If you can sound sufficiently like an alarmed titmouse, you should be able to create the same reaction. Sometimes the birds ignore you entirely, but in this case it was quite effective. At one point (captured here), the redstart actually swooped down low over my head, either searching for, or mobbing, the source of the sound.

Male redstarts take a couple years to get this nice crisp black-and-orange plumage. In their first summer as an adult they still sport the brown-and-peach colouration of the females, although it’s often mottled black, especially around the face. That fall, when they go through their complete moult, they’ll replace all their drab feathers with striking black ones. This delayed mature plumage fits into the dominence hierarchy; black males almost always get to mate, brown males only if there aren’t enough black males to go around. Not that that stops them. Brown males will float between the territories of black males, and when the older one’s got his back turned, the younger one will usually slip in for a quick fling with the missus. The females have no problem with this; the more males she mates with, the better her chances of having mated with a genetically superior male. This guy probably wasn’t going to stick around to breed, though – although they do nest in the Greater Toronto Area, he was probably heading further north to better habitat.

There were a couple of Yellow Warblers hanging out in the same tree as the redstart, checking me out as I pished at them (you can see one with the redstart in the earlier photo). It appeared to be a male and an older female (differentiated from younger females by the brightness of her yellow plumage), but could have been two males. Yellow Warblers might be the most common warbler in the Don Valley, and probably much of southern Ontario. They’re usually found in riparian areas, in the scrubby vegetation that lines stream and wetland edges, but can occasionally be found in other habitats, as long as they’re similarly shrubby. It was a bit odd to see the pair at the rail tracks, since there didn’t appear to be water immediately nearby, but I will admit I didn’t know what was on the other side of the berm bordering the north side of the tracks.

Mrs. Cardinal came out and gave me a good look just to make sure the fuss wasn’t anything worth getting too upset about.

Mr. Cardinal did the same, but hung back in the vine tangles. Neither of them stuck around long once they determined that it wasn’t actually a titmouse getting worked up over an owl or something. The tangled thicket they were hanging out in was a good place for a cardinal nest, but I didn’t actually climb up to check the area out. Cardinals actually used to be fairly scarce through this area, some decades ago, but are now a dime a dozen. The reason for their expansion is usually credited jointly to the increasing popularity of bird feeders along with gradually warming average temperatures. It’s been observed that as the temperature isotherm for the January mean minimum temperature of minus 16 C moves north, so does their range. Their northern range limit is now more restricted by availability of their preferred habitat than by temperature.

A catbird was singing from a patch of sumac along the edge of the tracks, and stopped to come check me out as I pished. Catbirds take their name from the sound they make when alarmed – which sounds rather like the nasal mew of a cat. They’re a member of the family Mimidae, the mimics. Along with the Northern Mockingbird and Brown Thrasher, the Gray Catbird will pick up sounds from its environment and work them into its song repertoire. A single catbird may have dozens of different phrases. Male and female catbirds look the same; rather than looking at flashy plumage to choose a mate, female catbirds prefer males with larger, more complex repertoires, which presumably indicates greater intelligence and stronger genes.

There were also other birds along the corridor: a few American Goldfinches, an American Robin, a Baltimore Oriole, a Warbling Vireo… These guys weren’t as obliging for a photo, tending to remain higher up in the treetops, hidden behind leaves and out of the reach of my camera. There were many other bird species in the rest of the park, as well, but even just in this small stretch of train tracks I was pleased with the diversity I found.

One for Sherlock

A week and a bit ago, when I was down at TTPBRS to allow the coordinator a much-needed day off, we caught a Rusty Blackbird. It was a rather slow morning, we hadn’t caught many birds, so this caused a bit of excitement. Although Red-winged Blackbirds are a dime a dozen, Rustys are the opposite. We see them every season, but in very small numbers, rarely more than one or two at a time, and usually only a handful over the course of the whole season.

This year the water levels are very high on the lake, possibly the highest we’ve seen them in the five years we’ve been there so far. A couple of our net lanes are located close to the water’s edge, and as the water level has crept up, the lanes have become flooded, such that we now require rubber boots to be able to wade in to check them. This is great Rusty Blackbird habitat, as they, like their cousins the Red-wings, are partial to water, and indeed this was the net the Rusty was caught in.

As we do with all birds, we banded him and took a few measurements and then let him go (after an obligatory, but short, photo shoot). He flew up into a nearby birch where he perched for a few moments, straightening out his feathers and checking out this new accessory on his leg. I couldn’t tell how old he was specifically; most songbirds can be aged as far as whether they were a baby or a parent last summer because of the way the two age classes moult their feathers (adults generally moult everything, while young birds only replace a subset of their nest feathers prior to migrating). However blackbirds are one of those exceptions to the rule, and all I could say was that I knew he wasn’t a 2008 hatchling.

In the top photo you can see the rusty tips to the glossy black feathers that give the species its name. We tend to think of a lot of species as having “breeding” and “winter” plumages. In most cases, these breeding plumages are obtained through a second moult in the spring. However, there are a few that only have one moult a year, in the fall, generally before they migrate. Their breeding plumage is obtained through the general wearing down of the feather tips over the winter. European Starlings are a good example of this that most people are familiar with. In the fall the birds replace all their feathers with fresh, white-tipped ones. Over the winter the white tips wear off revealing the oily-black breeding plumage. Snow Buntings are another, rather dramatic example of this type of plumage “change”. In the case of Rusty Blackbirds, their rusty tips wear down to form their black breeding plumage. This individual is an adult female that we banded a couple of years ago in the fall. This year’s male is the first that I’ve banded in the spring. Although we see them both seasons, they’re ordinarily a fall capture.

Rustys are just migrants through our area. They do breed in southern Ontario, but only once you get up onto the rocky Canadian Shield. There they favour forested wetlands and swamps, particularly fens, bogs and muskeg. In the recently published Ontario Breeding Bird Atlas, the southernmost record for the species were concentrated around Algonquin Provincial Park, a huge expanse of protected boreal forest about three hours north of Toronto, just a few shades shy of Yellowstone National Park in size. They nest as far north as Hudson Bay, where they tend to breed in muskeg along creeksides. They reach their highest breeding abundance in the Hudson Bay Lowlands, where they can be relatively common, though never as abundant even in their peak areas as Red-winged Blackbirds are south of the boreal forest.

Population monitoring surveys such as the Christmas Bird Count and Breeding Bird Survey have shown a rather alarming trend for the Rusty Blackbird. Since BBS counts started in the 1960s, the species has declined by about 95%. Put in other words, only 5% of the population that existed in the 1960s still remains today. The reason for this incredible decline remains a bit of a mystery, as other species that share their habitat and food preferences on the breeding grounds have not shown the same dramatic trends, although many species that breed in boreal wetlands have been declining to some degree. This may be in part due to acidification of boreal wetlands by acid rain (the limestone rock base south of the shield does a lot to neutralize the acids in the water here, but on the shield the rock is granite which doesn’t have the same properties, so groundwater becomes acidic), or, more recently, chemical or physical changes in boreal wetlands as a result of global warming. But it doesn’t explain the huge decrease in numbers of the Rusty Blackbird.

The answer may instead lie on the wintering grounds. In the non-breeding season blackbirds and related species will congregate to roost in flocks of often hundreds of thousands of birds. They target the waste grain left behind in harvested agricultural fields, but also become a pest to growing crops, particularly ripening corn and sunflower seeds. Blackbirds aren’t protected by the same laws of the Migratory Bird Act that cover other songbirds, and they’re often persecuted as agricultural pests. Surfactants are sprayed on roosting winter colonies that disrupt the birds’ natural water-repellent protection, and the birds succumb to the elements. Despite that Rusty Blackbirds don’t actually feed in agricultural fields very often (even in the winter they prefer wet woods for foraging), they tend to join these communal roosts at night, and so are targeted by the same control methods.

Virtually all species of blackbird are in some level of long-term decline (this includes the widespread and widely abundant Red-winged Blackbird, which is nonetheless declining as well). Why the Rusty should have been so dramatically affected when other birds haven’t been is hard to say, and is part of the mystery behind their population crash, however another likely factor is the gradual loss of wet woodland habitat on their wintering grounds as it’s converted for agriculture and development. It may be that a combination of breeding ground and wintering ground factors are coming in to play to cause the species’ decline.

Because the cause of their decline is still uncertain, it is difficult to form a plan of action to protect the species and bolster its numbers. All we can really do for now is to try to protect the birds on their wintering grounds, maintain the habitat they require there and during migration, and continue to monitor their populations.

It’s sad to think that once upon a time, not so long ago, Rusty Blackbirds may have rivaled some of the other blackbird species in numbers during migration and the winter. Nowadays, it’s a real treat to spot one of these guys as they make their perilous way north and south.

Red-tail fly-by

I was down at the station yesterday, one of two days a week I’ve been going down. It was an absolutely lovely day, cool at startup, but not cold, and warm enough to strip down to a single layer by the time we wrapped up at noon. I pulled out my sunglasses and wore a ball cap instead of a toque for the first time this spring. Naturally, on these first, early sunny days of spring I can never seem to remember to pull out the sunscreen, and so I inevitably get lightly sunburned. At least it’s not the painful, peely sort.

Despite a relative dearth of birds yesterday, there was a good diversity of species. One of the birds hanging about the station was this beautiful Red-tailed Hawk. Red-tails are rather uncommon birds at the station. This isn’t necessarily reflected in the log book, where we often record hawks sailing over high. It’s also not really applicable to the park as a whole, where there’s usually one or two hawks hunting the broad, open meadow areas that cover most of the land area of the park. However, down on the station’s peninsula it’s mostly early successional forest, with enough trees and shrubs to make it less than ideal for the usual hunting tactics of a Red-tailed Hawk.

This guy (or girl; although hawks are dimorphic, it’s by size and not plumage, and a hawk sitting on a branch fifteen feet away just looks large no matter which way you cut it) flew right up and perched just beside the station building, where I was in the process of doing some training with a new volunteer. We both stopped and ogled the hawk while it sat there, since it’s not often that a wild raptor will oblige you with such flattering views. I did my best to run off a few shots, despite the backlighting. A moment or two later he decided further down the road might be better, and he took off from the branch, soaring by just a few feet above my head, close enough that had I desired to (and had the reflexes to), I could have reached out and snagged a few feathers at his passing.

I’ve handled a Red-tail before, though – we banded one in 2004, my second fall at the station, when I was there in official capacity as an assistant (now I’m an unofficial, volunteer assistant instead). Boy, do I ever look young in that photo. Normally birds this large don’t stick in the net very long, if they even fall into the net in the first place; just as often they’ll bounce right off the mesh and carry on. If they do fall into the net, they’ll likely take a minute or two to flap their way to the end of the net, where they can find some tension in the mesh to pull against to launch themselves out. This assuming that they don’t bounce out before reaching the end. In the case of the above, one of our volunteers happened to be just approaching the net at the time when the hawk flew in. A flailing hawk in a net is extremely dangerous, so we ask our volunteers to call for myself or the coordinator rather than tackle it themselves, but she was able to get help over very quickly. It’s the only Red-tail banded by the station to date, and one of just three large hawks (the other two being a Cooper’s in 2003, and a Northern Harrier in 2005). However, if this Red-tail continues to hang about low the way he has been the last few days, it’s likely that eventually he’ll blunder into a net. Hopefully we’ll be there to snag him.

A bit later we observed him fly from his perch in a tree down to the leaves on the ground in an open patch of trees. He hopped about here, clambering over sticks and tangles, looking for I’m not quite sure what. Insects? Although they prey primarily on rodents, Red-tails are opportunistic hunters, and will eat large bugs like grasshoppers if they’re available. They’ll also take rabbits, which can be very abundant at the park, but I doubt he’d be hunting those on foot. I don’t think he was after grasshoppers this early in the season, either. Snakes are a possibility, I did see a few out in the warm weather, and they’d still be a bit sluggish in the early morning cool. You can see a smear of blood on its upper breast in the first photo, so it was obviously finding something to eat down there.

I never actually saw him snag anything while he was on the ground, so it might be he was just looking. On the other hand, he stayed pretty well hidden behind a low ridge and some trees the whole time, so it was difficult for me to see everything he was up to. It may be that this particular individual was less dominant to the ones that frequent the meadow habitat, and was here less by choice than because he was forced out of the other areas. Or perhaps he just desired a change of scenery.

A minute or two later, after deciding there wasn’t much worth looking for down on the ground, the hawk turned about and took off – once again straight toward me. Red-tails can travel at up to 20 to 40 mph (30 to 60 km/h) at cruising speed when flying. I doubt that this guy was going that quickly, but he was moving too fast for me to be able to get my focus adjusted well.

I managed to snap this shot just as he soared by me; a little further this time than the first, I probably couldn’t have touched him, but it was still closer than I usually find hawks flying by me! I got the impression that while he was wary of humans, and kept an eye on us, he wasn’t terribly concerned. He was down there again today (I wasn’t), flying about the area, and demonstrating a similar coolness toward the people.

He swooped up to perch in a tree not far from me, before departing for parts unknown.

Start of the season

Contrary to the forecast made for yesterday, the weather wasn’t actually all that bad. While there was rain in the city, by the time I drove the ten minutes down to the spit, there was no rain down on the lakeshore, and there was even some patches of blue sky struggling to show through the blanket of grey cloud. It’s a funny thing about the research station, that the weather conditions that affect the city can often be quite different than what’s happening out on the spit. Usually, it’s that it’s raining, sometimes heavily, in the city with little to no precipitation on the lake. Strange.

Today dawned clear, beautiful and sunny, but c-c-cold. Well, for this time of year. It was -5 celcius when we arrived at the crack of dawn, about 6:30am. It took until 9:30 for it to warm up to 0 degrees. Ordinarily we would open the mist nets half an hour before sunrise, and run for 6 hours, but both yesterday and today, due to weather, we opened halfway through the morning and put in just a half day’s worth of effort.

The first bird banded of the spring season was this impatient American Tree Sparrow (can you see the look he’s giving me? “Are you done there yet, missy?”). After my comments about expecting migrants to be late this year, they all seemed to come in on the warm front Monday night. We had Golden-crowned Kinglets and Eastern Phoebes, in good numbers. Song Sparrows, juncos, a few Brown Creepers. A Winter Wren was around, as was a Yellow-bellied Sapsucker and a Belted Kingfisher, all firsts for the spring.

We totaled a huge 41 species on the morning, which I think is more than any other opening day in past years. One of the birds present was this little Northern Saw-whet Owl. They’re not often seen in the spring, so it was a real delight to find. Saw-whets are funny migrants, they come through in largeish numbers in the fall, spread out for the winter, and then seem to just disappear come spring. We run a saw-whet owl monitoring program in the fall which is pretty successful (we banded over 300 owls last fall), but don’t run in the spring because there’s no owls around to band!

The trails are still partially covered in snow. This photo was from yesterday, and the rain and wind yesterday helped to melt some of it, but there’s still some left yet to go. It can be a little bleak down there on cloudy days in late fall or early spring, with the grey skies and empty trees. The trees take a while to leaf out, longer than on the shore, because of cooler temperatures due to lake effects. We can just be seeing the start of greening when trees are already well-progressed in town. The dogwoods really help add a pop of colour to the landscape there. I’m going to try to do a once-a-week photo series documenting the greening of the station this spring.

As I was leaving yesterday, this woodcock wandered across the road in front of my car. Naturally, I had my camera already packed away, and of course it had the short lens on it. So while it was a rare opportunity to see a woodcock out in the open, this was the best shot I could manage. I love these birds, they’re so bizarre-looking! They’ve been doing their beautiful twittery sky-flights in the mornings when we arrive, I wish it was brighter when they do it so that I could capture some of it to film, but they only fly at dusk and dawn.

I’ve been busy lately, wrapped up in an interesting and hopefully promising project that will hopefully be the subject of some future post if it all works out, so haven’t had much time for research – I’ve got a small backlog of such photos that I need to get to. It’s amazing to me how much there’s been to talk about during the winter, the months that I figured would be the hardest to fill… My camera will be overflowing when life really starts stirring in a few weeks!

On your mark… get set…

The last day of March, and this morning found me down at the Tommy Thompson Park Bird Research Station, helping to set up the site for the start of another fabulous spring migration season. The research station’s primary goals are to collect data on local and migratory bird populations to aid with conservation efforts here and afar, to promote awareness of birds and conservation through education programs and demonstrations, and to contribute to research initiatives by helping to collect data or providing a location or means for someone else to do so.

The primary, and initial, project run by the research station, through which these objectives are achieved, is the migration monitoring program. It involves constant-effort bird banding and surveys (that is, we’re out there every single morning for the entire migration period, weather permitting), which provides data on bird population numbers and demographics, including information such as adult:young and male:female ratios in the population, stuff that can’t be easily (or sometimes at all) obtained through non-banding means but that gives you an idea of, for instance, how successful the breeding season was this year. There are some 25 or so similar stations across Canada, each contributing valuable data to fill in their local piece of the puzzle. The birds are banded, measurements collected, and then safely released to return to their regular activities. The Palm Warbler in the top photo popped nearly straight up out of the hand before taking off for the nearby trees.

I’ve been volunteering since 2003. I love being down there, and would happily volunteer all season if I had some other means of making ends meet (who’s seen/read About A Boy? perhaps all I need to do is write a hit holiday song and I’ll be set). I like seeing who’s about every day, watching the migration ebb and flow across the season, the composition of species progressing and changing from week to week. On a daily basis, I like turning the corner to check a net, not knowing what we’ll find this time around. We’ve had some marvelous surprises show up, such as the above Yellow-throated Warbler, the only bird of this species I’ve seen (they’re normally more southerly in range).

I love the opportunity to hold such fragile, but beautiful, life in my hands, to feel the wonder of it. I enjoy seeing the birds up close, at a distance where you can marvel at the intricate feather patterns or subtle plumage details often lost in the field. Who’s seen the orange crown of an Orange-crowned Warbler? I have, but only with the bird in my hand. And who’s paid much attention to a Mourning Dove’s face, the subtle colours of the eye ring, the bright pink at the corner of its mouth, the small patch of iridescence on its neck? But you get a chance to see this when you study the bird up close.

Yes, I’m looking forward to returning. Ironically, tomorrow, the first day of banding, has been rained out (we don’t run in conditions that would threaten the welfare of the birds, though surveys are still a go – we’re less concerned about our own comfort). So we’ll be starting on Wednesday instead.

The setup this morning went smoothly, but was quiet for birds. We had a group of a dozen chickadees moving back and forth through the area, and there were some blackbirds and a few grackles that flew overhead throughout the morning, but not much moving in yet. Perhaps this warm spell will encourage some more movement from the south. Hermit Thrush, American Tree Sparrow, Dark-eyed Junco, perhaps even Eastern Phoebe or Ruby-crowned Kinglet – they should all be around in the first week during a normal season, but the unusually cold weather might delay their arrival this year.

The park and station are open to the public on weekends and holidays, and anybody in the Toronto area who’s interested is invited to swing by Tommy Thompson Park on the Leslie Street Spit, and drop in during a spring or fall morning to check us out, learn about what we’re doing, and get a chance to see a little bird up close and personal.