Exploring Burnaby’s Parks and Natural Areas

Saturday November 22, 2014 saw the inaugural walk in the series I’ll be leading over the next few months called Exploring Burnaby’s Parks and Natural Areas.

A keen group of eleven participants, we found ourselves outdoors on a beautiful fall morning – blue sky, fluffy cumulus clouds, and sun. Yes, sun. Luckily, it seemed the weather gods were looking upon our enterprise favourably. We managed to find the one fine day between soaking Pacific fronts that had been storming across the region on the belly of the jet stream for a week; and then continued the downpours afterwards.

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Searching for a Fox Sparrow skulking in a blackberry thicket

Starting at the rugby fields at the foot of Sprott St., we wanted to see as much as we could during a relaxed 3 hour walk by following the Still Creek corridor upstream from its outlet at Burnaby Lake.

However, before we got to creekside, the large flock of Canada Geese on the rugby fields (not playing of course) got our attention. Taking a closer look at the more than 150 birds happily grazing the grass fields we noticed that in fact there wasn’t a single Canada Goose among them. They were the Canada’s smaller cousin, the Cackling Goose. Originally thought to be just small Canada Geese, scientific studies, including genetics, have recently shown these birds to be a separate but similar species,

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Cackling Goose. Note the darker colour, small, rounded head, short neck, and small bill which separate the Cackling from the Canada.

Looking around from the parking area, we had excellent views of a flock of American Goldfinches actively feeding in the treetops. After walking across the fields to the banks of Still Creek, we were soon appreciating the many waterbirds at the mouth of Still Creek including Double-crested Cormorants, Buffleheads, and Common Mergansers. Shortly after, we walked north-west along the creek where we saw our Bird of the Day, a beautiful adult Northern Shrike, an uncommon bird in Burnaby. Perched at the top of a large black cottonwood, it was out of camera range unfortunately, but the spotting scope provided great views for everyone.

As we continued, a shrubby area off the main trail featured our most active group of birds for the morning feasting on the berry-sized fruit of Pacific crab apple trees, and red-berried hawthorns. Cedar Waxwings, Purple Finches, American Robins, Spotted Towhees, and Fox Sparrows made up the mixed feeding flock.

In all during the walk, we saw about 30 species of birds, but I won’t retell the details of each sighting, but encourage you to join us next time to see them for yourself. The schedule of walks and details will be published by the City of Burnaby. The dates are:

Saturday Jan 10 – Burnaby Lake Winter Water Birds
Friday Apr 17 – Welcoming Spring at Deer Lake Park
Tuesday Apr 28 – BBY Mnt Conservation Area Spring Songbirds
Saturday May 9 – Dawn Chorus at Deer Lake

A full list of our sightings on November 22 is shown below.

Cackling Goose  150
Canada Goose  6
Wood Duck  2
Mallard  10
Bufflehead  8
Hooded Merganser  1
Common Merganser  3
Double-crested Cormorant  25
Cooper’s Hawk  1
American Coot  7
Glaucous-winged Gull  5
Rock Pigeon (Feral Pigeon)  25
Downy Woodpecker  2
Northern Flicker  3
Northern Shrike  1
Steller’s Jay  1
Northwestern Crow  60
Black-capped Chickadee  8
Brown Creeper  1
Pacific Wren  2
Golden-crowned Kinglet  1
Ruby-crowned Kinglet  2
American Robin  40
European Starling  20
Cedar Waxwing  12
Spotted Towhee  10
Fox Sparrow  5
Song Sparrow  8
Purple Finch  5
American Goldfinch  25

 

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July – Moult Month for Waterfowl

July is mid-summer for us humans, and the time of year when we head out to our parks and beaches. However, despite the attractions of the season, it’s just not as pleasant and pretty down at the Deer Lake beach as it usually is. In fact, things are looking downright scruffy and untidy.

All that feather shedding and goose pooping are making quite the mess. What’s going on?

For sure it’s the birds making the mess, and over one hundred Canada Geese can make a good one, but before getting ticked off, spare them a sympathetic thought. July is a pretty tough month to be a goose or a duck. They’re going through a big part of their annual moult. It’s biology and they have no choice.

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Not a pretty sight – moulting geese crowd Deer Lake beach

Walking around the beach, feathers are strewn everywhere and most of them are from the park’s ducks and geese.

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For all species of waterfowl (ducks, swans and geese), moulting is a pretty dramatic and stressful affair. Not only do they shed some of their body feathers, but also their wing feathers. And not just one by one; waterfowl lose their flight feathers all at once. Now if your flight feathers are gone, you’re flightless, and that can be serious – especially if you need to escape from a predator.

So our ducks and geese gather in areas where they have easy access to an escape route – in this case to the lake itself. The beaches at Deer Lake and Piper Spit at Burnaby Lake offer great locations for moulting birds.

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Canada Goose with all its flight feathers missing from moulting

Take a look at the goose above. The long, dark wing feathers that extend to the rear and partly cover the tail are completely missing and expose the black back and white rump that we see like this only at this time of year.

Here’s another bird, and here you can see the newly growing pin feathers, or blood feathers as they are also called. Over a period of a couple of weeks they will become fully developed and fully functioning wing feathers, or primaries. Right now they’re just tiny stubs.

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Note the emerging wing feathers encased in a blue, waxy coating on each side of the bird

The base of the pin feathers shown above are engorged with blood to aid their rapid growth. You can just see the new feather material emerging from the tip of the waxy coating. Damage to these pin feathers at this stage can be dangerous for the birds – it can lead to significant blood loss.

A little further along in the moulting process, here’s a bird with partially-grown new flight feathers that have not yet reached their full length.

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The dark-coloured, newly growing flight feathers (primaries) are best seen on the bird’s left wing. Note the still-to-be-moulted, old, paler, worn-looking, unshed flight feather on the extreme lower left.

As the flight feathers continue to grow they will once again cover the white rump and much of the tail. The bird above is also growing replacement tail feathers – note the uneven length at the tips. Growing so many large feathers at one time uses a lot of the birds’ energy, and they tend to loaf around to conserve it.

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Loafing on the beach, and then bathing in the lake. Remind you of anything?

Loafing on the beach enables the moulting birds to bathe frequently and preen those new feathers into good condition. This is important work; they will have to last until this time next year before being replaced.

Ducks also moult their flight feathers after breeding, but their transformation is even more dramatic. As they moult their wing feathers, they enter what is known as eclipse plumage. The males loose all their fancy body feathering, and often look much the same as females of the species. However, given they are flightless, it’s no doubt best to be as inconspicuous as possible. Plus the fancy, female-attracting plumage is no longer required now that breeding has just finished.

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This drake Mallard is losing his glossy green head feathers, rufous breast plumage and gray back and sides as he moves further into eclipse plumage

Here’s a picture taken earlier this year showing how much the drake Mallard transforms from eclipse to breeding plumage. Eclipse above, breeding below.

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Breeding plumage Mallard – the plumage we see most of the year

Ducks are very unusual in the bird world as the males have their two annual moults very close together in summer and fall. Most birds that take on different plumages for the breeding season have their second moult in the spring, ready for the breeding season.

Ducks in contrast, form pairs in the winter and males develop their pre-breeding finery during fall to be ready for winter pre-breeding pairing.

Lastly, here’s a very scruffy looking Gadwall at the lake.

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A very “female looking” drake Gadwall in eclipse plumage

Along with moulting waterfowl, many other birds  also undergo a moult at this time of year. Just like our ducks and geese, even our crows come down to the beach to make use of the fresh water from Buckingham Creek to bathe and condition their new feathers.

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Moulting crows gather around the mouth of Buckingham Creek

Unlike waterfowl, crows do not moult their flight feathers all at once, but lose and replace them serially over a period of several weeks. Such a moult strategy enables these birds to continue flying while undergoing this annual transformation. Looking up at crows flying overhead at this time of year you will notice the shape of the wings at the trailing edge is somewhat jagged, the result of new feathers growing in and others having been shed.

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Crow showing its moult in progress

The picture above is really illustrates what’s going on. This Northwestern Crow photographed last week at Deer Lake shows both body and wing feathers being replaced. The old, sun-bleached, brownish feathers contrast quite strikingly with the glossy, black new feathers just growing in. This bird has also lost feathers at the base of the bill, likely as a result of continually stuffing food into the mouths of its hungry young. All will be restored to glossy glory in a few weeks.

It’s enough to make you want to take a bath.

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Bathing Northwestern Crow, Buckingham Creek

While photographing the geese, ducks and crows shown above, I suddenly noticed feeding right along the edge of the Deer Lake beach were these two Long-billed Dowitchers – a rare treat at this location.

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Long-billed Dowitchers newly arrived from Northern breeding grounds

These two birds are adults in worn, breeding plumage. You’ll have to take my word on the “worn” part. Now these sandpipers have a different moulting strategy from the birds we’ve looked at so far. After breeding, the dowitchers migrate from the breeding grounds and then moult into their drabber winter plumage on the wintering grounds.

And many Long-billed Dowitchers spend the winter at Burnaby Lake. Here’s a picture from last winter. Look at the transformation. Breeding above, winter below.

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Long-billed Dowitchers in winter plumage

You can just see in the flanks of the bird below the first few hints of the greyer feathers of the winter plumage.

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Long-billed Dowitcher, Deer Lake beach

With all this shedding of feathers and growing of new ones it’s enough to make you want to scratch that itch. It’s that time of year.

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****

It’s been a busy spring of birding and travel that has kept me away from the blog. However, it’s back, at least for a while.

 

Northern Harriers – Update

Perhaps quite predictable, but good news nonetheless for the prospects for raising another generation of Northern Harriers at Deer Lake was the arrival on the breeding territory of a female harrier just a couple of days after the male was scouting out the lay of of the land.

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Female Northern Harrier newly arrived on her breeding territory.
Photo: Jason Hung

And of course we can anticipate the outcome of a male and a female on the breeding territory. The male was soon in courtship mode, and pursued the female whenever she landed on the meadow.

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Male harrier takes off in pursuit of female
Photo: Jason Hung

Copulation was not captured photographically, but here the male is approaching the female very closely.

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Harrier pair. Photo: Jason Hung

In the meantime I’ll keep you posted as events unfold. Even better, get down to the meadows and check out the action for yourself. However, please keep out of the meadows and observe from the trails. The birds’ breeding success depends on us, and our dogs not disturbing them.

I’ve also updated the photographs with higher resolution images on the previous post about the harriers at Deer Lake. Click here to view that post and the upgraded images.

Northern Harriers – A Sign of Spring

Not only is the calendar telling us that today (March 20th) is Spring Equinox, but nature too is showing us the seasons are changing. The first Tree Swallows of the year showed up at Burnaby Lake just over three weeks ago, and there are all sorts of signs of spring in our parks. From the blooming of the indian plum in the forests, to the peeping of tree frogs down at Burnaby Lake, all confirm what the birds are telling us – spring is here.

For me, one of the most exciting signs of spring is the return of the Northern Harriers to their nesting area in the meadows at the west end of Deer Lake. And just this past Friday (March 14) I saw the male harrier checking out his regular nesting area.

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Male Northern Harrier checking out its nesting territory prior to breeding

Not a great picture, but the bird was far out in the meadow. Below is a much better picture of the male harrier in flight. Jason Hung, who kindly let me use some of his photographs for this post (thank you, Jason), has much superior pictures of the birds than I can capture with my more basic camera gear. A lot of patience waiting for the birds to fly close-by is needed, and Jason’s patience and skill with a camera has certainly paid off. He’s managed to get some great shots over the past couple of years.

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Male Northern Harrier photographed at Deer Lake by Jason Hung

The fact that we’ve got harriers nesting at Deer Lake, is a real feather in the cap for Burnaby Parks – pun intended! We’re tremendously fortunate to have them nesting pretty much in the centre of the City because harriers need undisturbed wetlands or grasslands in which to nest and raise their young. Unlike many raptors, harriers nest on the ground, and as a result are very susceptible to disturbance from people and dogs. The Deer Lake birds arrived here about 10 years ago, and set up nesting territory in the park. As the park has got busier over the years with the increasing population around Metrotown, the pressure on the birds’ habitat has increased. At least once in the past few years, a dog killed a young harrier on the ground, but in most years the pair has successfully raised one or two young.

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This city sign is important protection for our ground-nesting Northern Harriers. Let’s watch and enjoy them from the nearby trails.

Now known as Northern Harriers, these birds were previously named Marsh Hawks and many readers may know them by the previous moniker. “Hawk” is a generic name applied to many raptors, but in the case of harriers it’s not a particularly apt descriptor.Compared to other North American raptors, harriers have a number of unique characteristics. Firstly, the males and females have strikingly different plumage; they are sexually dimorphic. As can be seen from the photos above, the males are grey backed, and mostly white underneath with black wingtips. The females, in contrast to the males, are mostly shades of brown above with buffy, streaked undersides.

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Female Northern Harrier. Photo: Jason Hung
Click to enlarge

Looking at the picture above, it’s possible to see that harriers have another interesting feature not found in other day-hunting raptors. They have facial disks like owls, which perform the same function for harriers as they do for the raptorial nightshift. They focus the sounds of prey to enable the capture of mice and voles, even when they may be out of sight in thick grasses over which the harrier is gliding.

Even more interesting, perhaps, is that the males are polygynous i.e. they mate with more than one female, sometimes up to five. However, mostly they are monogamous or bigamous, and in all cases the males provide most of the food for both females and the young. Our male at Deer Lake has typically had two females to provide food for. The second nest is in a virtually inaccessible part of the park, and while the patch of habitat is smaller, it may be more protected from intrusion because of its isolation.

The provisioning of food for female and young by the male gives us the opportunity to see a very exciting and dramatic event. When the male returns to the incubating female sitting on the nest, he gives a whistling call, which is the signal for the female to get airborne. Once she’s up and flying she also calls insistently. The male, flying higher, drops the prey for the female below to pursue and to catch in mid-air. It’s a wonderful aerobatic display.

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Male above, female below with prey just released by the male.
Photo Jason Hung

When the young are flying, the adults will drop in prey for the young to catch in mid-air. Below, Jason once again captured the action. This time it’s the female making the aerial exchange with one of her young.

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Female to young prey exchange. The in-transit food is probably a Townsend’s vole.
Photo: Jason Hung

The next couple of months will provide many opportunities to observe the comings and goings of the Northern Harriers at Deer Lake. Keep your distance, and enjoy the show. Nesting starts in earnest in the next couple of weeks. Spring is definitely here.

They’re Back!

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Three of five chum salmon spawning in Buckingham Creek this morning (Nov 6th).

After last year’s salmon surprise at Deer Lake, the chum salmon are back again this year attracting the curious, bringing smiles to people’s faces, and causing gasps of excitement. “They’re Back!” Not the return of last year’s fish, of course, but a new run of chum salmon has surged up Buckingham Creek at the east end of Deer Lake, almost to the day they appeared last year.

The fish are actively flushing the accumulated silt from their redd (spawning bed) and getting on with the business of producing the next generation.

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Vigorous body undulations, and splashy tail action cleans out the redd ready to receive the chum salmon eggs.

After a fantastic journey to and from the Pacific Ocean where they arrived as smolts, and spent from 3 to 5 years growing to maturity, these fish are returning to spawn in this tiny urban waterway. Last year’s post gave more detail about the journey these fish have made to return here to spawn.

Periods of rest separate periods of vigorous activity, perhaps not such a surprise after such a long journey. But spawning is a strong urge and the salmon give their all in the final act of reproduction. In a couple of weeks, we’ll see their spent carcasses in the creek.

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After some energetic gravel cleaning, the fish rest awhile before continuing their spawning.

Don’t miss out. Welcome back our urban salmon. The action won’t last for long.

Halloween Nightmare – for a snail!

It’s All Hallow’s Eve. Gore-spattered ghosts, ghouls, and goblins roam our streets in packs.  Vacant eye-sockets glare at us from dark doorways, and dripping bushes. Blood curdling wails of pain and screams of fear echo through the neighbourhoods.

Putting the frighteners on ourselves is all part of the fun, and the scary stuff is not that nightmarish when we know that once all ‘tributes’ have been collected, a warm home awaits us with hot chocolate and a feast of goodies.

However, from our comfy seats at home, can we give a thought for the lowly snail? If snails could think like we do (they don’t) surely their Halloween Nightmare would be one that would terrify us too – trapped, unable to move, and being eaten alive, head first, Hannibal Lecter style.

And that’s what’s happening below; not in the movies, and not in our imaginations, but for real.

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Calosoma ground beetle eating a snail.
Click to enlarge.

With the beetle’s mandibles plunged into the opening of the snail’s shell, the hapless gastropod is being eaten alive, head first. I witnessed the dramatic scene above while gardening this week .

Ground beetles, like the one above, are quite common carnivorous denizens of our gardens. Often unseen because of their nocturnal habits, we frequently disturb them while digging around in our gardens. Far less frequently do we see them with their prey.

However, it’s a good reminder that many of the invertebrates in our gardens are actually doing us favour, although I’m sure the snail wouldn’t see it that way. In this case our friendly beetle is consuming a garden-plant-eating snail. Remember: Don’t squash the insects, and do avoid the pesticides!

The two hard “shields” covering the back of the beetle and protecting the wings underneath are called the elytra. They are nicely striated in the above specimen, and suggest that it’s in the Calosoma genus. As I’m a bird man, and less of a bug man, my identification of the beetle is provisional.

And while I’m on the topic of ground beetles, I thought I would take the opportunity to share a picture of another striking member of this large family of insects. I managed to photograph this beauty last year in my garden after a brief shower left it with a shiny coating of water over its smooth, red elytra. Again, my identification is provisional. I believe this one is a member of the Carabus genus.

Both beetles are in the 25 to 30 mm size range.

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Carabus ground beetle after a rain shower.
Click to enlarge

Take a close look at the beetle above and you’ll notice it’s missing part of its left front leg, and part of its right antenna.  It’s an eat-and-be-eaten world all around us. So if snails could have Halloween nightmares, then I’m certain that ground beetles would have theirs too. Who can imagine what frightening beasts could attack and dismember ground beetles?

Happy? Halloween.

Alien Invader Arrives in Burnaby – finally!

The Eurasian Collared-Dove’s invasion of North America is a remarkable story. This dainty member of the pigeon and dove family has found human-altered landscapes to be just what it needs to breed rapidly, and spread like an avian tsunami across the continent from east to west. The bird’s arrival here in Burnaby may be one of the final chapters in its conquest of the whole continent, and in particular here on the West Coast. The surprise for me is that it has taken so long to arrive in our fair city.

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Eurasian Collared-dove. Since the bird’s introduction to the Bahamas in the 1970’s, its population has exploded and it has spread right across the continent.

For more than six years now, Eurasian Collared-Doves have firmly established themselves in Surrey, Delta, Ladner, Richmond, and up the Fraser Valley. Even though I have been watching out for them, to my knowledge they’ve only just arrived in Burnaby this summer.

Despite my expectation to find the bird here in Burnaby, it was readers of this blog who were the first to notice the alien species in our midst. Back in late July Brian Johnson sent me a couple of pictures of a “mystery” bird he was seeing and hearing in his yard. Bingo! Brian’s distant pictures provided the first evidence I had seen of Collared-Doves in Burnaby. Next up was a phone call a week or so later from Tony Fabian. “Hey George, I’ve got this odd-looking pigeon in my yard. I can’t find it in any of my bird books.”

It took me a couple of weeks more to actually see the birds for myself, and take some pictures that I could publish here. The birds have proved to be skittish, and difficult to get close-up photographs. Finally, my friend Ross McIlroy invited me around to his backyard where the doves were a new arrival at his bird feeder. Although I didn’t manage to get the hoped-for closeup, one of the birds was conveniently perched nearby.

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Favouring backyards and back lanes, Eurasian Collared-Doves frequently perch on power lines.

A frequent concern with introduced species, especially highly invasive ones like the Collared-Dove, is their negative impacts on our native species with which they compete for food, territory, and nest sites. So far, Collared-Doves seem to be living harmoniously in North America without significant impacts on our native North American doves and pigeons.

A case in point is its seemingly benign relations with my favourite local member of this family of birds, the Band-tailed Pigeon. It’s good to know this beautiful bird is apparently unaffected by this alien invader. Band-tailed Pigeons breed sparsely in forested areas scattered across our city, but they often show up in large numbers during Fall migration. Their favoured food at this time of year is acorns, which they swallow (whole!) to fuel their migration to points south.

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Band-tailed Pigeons have bright yellow legs, feet and bill, and beautiful, vinaceous body plumage. Click image to expand the image – this is a spectacular bird.

So what’s the difference between these two species – one native and one alien invader? Interestingly both have prominent neck collars and contrastingly patterned tails.

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The dark and light tail bands give the Band-tailed Pigeon its name – nice feeder bird, Ross!

The prominent white collar on the Band-tailed Pigeon above, contrasts with the prominent black collar of the Collared-Dove below.

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Dark collar, pale pastel overall, and dainty appearance characterize the Eurasian Collared-Dove.

So the aliens are now in our midst, and fortunately they are neither to be feared nor shunned. With some careful observation they are easily identified, especially if you are lucky enough to have them coming to a bird feeder in your garden.

Neither species should be confused with the familiar feral pigeon commonly seen along railroad tracks and in parks. That bird is the introduced Rock Pigeon, and that’s a story for another time.

To hear the cooing song of the Eurasian Collared-Dove click here, and then click on the play button.

Cooper’s Hawks

Cooper’s Hawks are likely the commonest raptor found in Burnaby, but much of the time you wouldn’t know it. Like all members of the accipiter family (true hawks) they are specialized, bird hunting, ambush predators, that mostly remain hidden deep in cover from where they launch surprise attacks, and pursue their avian prey through the woods.

However, in July and early August when the young birds have just fledged (left the nest), they frequently perch out in the open for a few days, noisily begging for food. Recently, friends in North Burnaby phoned to tell me that they and their neighbours were being entertained by a family of four recently-fledged, and two adult Cooper’s Hawks in nearby Montrose Park.

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Three of four juvenile Cooper’s Hawks await their parents’ return with food – Montrose Park.

When I headed over there the next day, the birds seemed to have learned their first lesson as young raptors – stay hidden. No doubt the youngsters had been mobbed by smaller birds, and the neighbourhood crows, which will attempt to drive all raptors from their territory. But, while staying hidden, they were still calling loudly for food. After a bit of searching, and using their long, wheezing whistles to guide us, we finally managed to find a couple of the young birds perched, and begging for food in the deciduous trees along the Trans-Canada Trail through Montrose Park.

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Juvenile Cooper’s Hawk concealed in big-leaf maple, begging for food

The adults were not  around when we were there, and were likely out hunting for the young birds’ next meals. Over the next two or three weeks the young will continue to be fed by their parents, but they will increasingly be left to their own devices until, and after four or five weeks, they will be abandoned to their make their own way in the world. If they haven’t honed their hunting skills sufficiently in the meantime, they’ll not survive. They may still hang around in the area of their birth up to six weeks after fledging. You should have a good chance of finding one if you head down to Montrose.

It’s a steep learning curve for the young Cooper’s Hawks to become independent hunters, but they’re born with all the equipment they need. Their incredibly sharp vision puts human  eyesight into the piker division. Cooper’s Hawks can not only resolve much greater detail at greater distances than humans, but they are also able the track the rapid movements of their prey through the forests, which for us would simply be a blur. Their binocular vision gives them the very precise judgement of distances which is essential for capturing fast-moving prey.

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Forward facing eyes give Cooper’s Hawks a wide field of binocular vision, essential for hunting.

Cooper’s Hawks wings are relatively short and rounded, whereas their tails are relatively long. You can see in the picture above the long extension of the tail beyond the wing-tips. This combination makes them stunningly maneuverable in flight. Fast to accelerate, they are able to make incredibly sharp turns at very high speeds to pursue their prey through dense vegetation. And they often seem totally fearless when chasing down their quarry.  I recall watching one chase a starling from a bird feeder, and then crash full force into a dense shrub, into which the starling had plunged to make its escape, only to yank it out, clutched in one foot.

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Long, sharp talons make for a deadly grip on the Cooper’s Hawk’s prey

Cooper’s Hawks are a success story in the urban bird world. Once in serious decline across North America due to hunting, pesticide contamination, and loss of forest habitats, they have now rebounded and adapted extremely well to urban environments, including our parks, where they find plenty of prey.

Andy Stewart in Victoria has had a long term program of banding and monitoring Cooper’s Hawks in the capital city, and he has discovered some of the highest densities ever recorded on the continent just across the Straight from us. I would not be surprised at all if we have comparable population densities of these beautiful predators right here in Burnaby.

Hawks banded in Victoria have been recorded a number of times on this side of the Strait of Georgia. Keep an eye out around your bird feeders this winter. Cooper’s Hawks often snatch their prey from our gardens.

To read more about Andy’s work, click here. A longer article, with a more continental perspective on Cooper’s Hawks can be found here.

Here Be Dragonflies

Written on ancient maps as warnings to mariners, Here be Dragons conjured up images of fire-breathing monsters lurking in unknown regions of the world ready to incinerate the unwary.

Here be Dragonflies is not a warning, but instead an invitation to head down to our local lakes and ponds to see these intricate and beautiful creatures that are just now taking to the air as the full heat of summer has arrived. Not scary, and not fire-breathing, dragonflies compete with butterflies as one of the top insect attractions in our parks and gardens.

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The eight-spotted skimmer is common, easy to see, and easy to identify. Photographed at Burnaby Lake, this one’s a male.

Living Fossils

Whenever I watch dragonflies, I’m always awed by the thought that these insects are the modern descendants of a fantastically ancient lineage. Fossil dragonflies, very similar to those we see today, were flying around almost 300 million years ago. That’s a staggeringly long time ago. As a comparison, the last Ice Age ended about 10, 000 years ago. Dragonflies have been around about 30, 000 times longer. Few animals living today have remained essentially unchanged for such a long stretch of geological time. When dragonflies were darting around the giant forests of the Carboniferous Period, mammals had not yet even appeared on earth. A very successful evolutionary “design” indeed.

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Eight-spotted skimmer female. Notice the different body colour, and lack of blue in the wings found in the male. Compare her black spots to the male’s, and you’ll notice they are the same size, shape and position on the wings.

Below is a second common Burnaby dragonfly – the blue dasher. What a great name! No doubt why it’s called blue, and it is pretty zippy in flight too. However, this dragonfly’s wings are not boldly marked like the eight-spotted. However, look at the rakish angle they are held in contrast to the more conventional stance of the eight-spottted.

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Blue dasher – male. Photographed at Deer Lake

Climate Change Connection

The blue dasher is found only in the most southerly areas of Canada; however it is a species that is likely responding to global warming. It has extended its range northward in recent years, and continues to do so. Not one of the dramatic signals that things are changing rapidly on the planet, but nonetheless, a signal from nature that they are.

Acute Vision

Dragonflies mostly feed on flying insects, sometimes even other, smaller dragonflies. To see, pursue, and capture their fast-moving prey they need fantastically sharp vision. The two large compound eyes which take up a large proportion of their head have evolved to capture even the slightest movement. Made up of up to 30, 000 individual simple eyes, the compound eyes of dragonflies not only give very fine detection of movement, but because in some species they form an almost spherical array around the head, they give a field of view approaching 360 degrees. Click the image of the blue dasher above to get a close look at its stunning turquoise eyes.

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Blue dasher – immature female.

Powerful Wings

No doubt part of the evolutionary success of dragonflies can be attributed to their wings. The intricate pattern of veins (venation) which carries blood to the wings also provides structural strength for powerful wing beats. Coupling this with the ability to flap and rotate all four wings independently, makes dragonflies incredibly manoeuvrable fliers. They can hover, rotate on a dime, make rapid vertical climbs and descents, and maintain forward flight at high speeds, and even fly backwards, all the time keeping the body horizontal.

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Four-spotted skimmer – female. The striking venation on the leading edge of the wing on this beauty is worth a closer look. Click to enlarge.

Dragonfly Cousins

Much smaller than their larger and more aggressive cousins, damselflies are also emerging in numbers and flying around the water’s edge at our local lakes and ponds. Slower moving than dragonflies, they hunt mostly by gleaning insects (aphids) hiding in the waterside vegetation. Damselflies are distinguished from dragonflies by the way they generally hold their wings closed over their bodies. The males, and some females, are mostly eye-catchingly blue, like tiny electric-blue pencils floating in the air on almost invisible wings. To many people damselflies are known as bluets, which is an entirely appropriate name. Bluet is also frequently seen as part of the common name for a number of species of damselflies.

Much more difficult to identify than some dragonflies, many species of damselflies look superficially similar. The one I photographed below is, I think, a tule bluet – a common species hereabouts. However, birds are where I’m confident in my identifications; I’m far less certain when it comes to damselflies. Please correct me if I’ve made a misidentification.

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A damselfly (tule bluet?) perched on lakeside vegetation at Deer Lake.

So whether it’s dragonflies or damselflies that catch your fancy, it’s time to take a look because Here (they) be….

And take your binoculars and camera. Close-ups are definitely in order when viewing these beauties.

If you’re interested to learn more about our local dragonflies, I suggest Dennis Paulson’s Dragonflies and Damselflies of the West. It’s also available in Burnaby libraries. I consulted the book extensively for this post.

Butterfly Bonanza

As we move into July and the weather really starts to warm up, the long grass meadows in our parks are the centre of a remarkable, once-a-year explosion of skipper butterflies.

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Skippers, crowding on to a blackberry flowerhead feeding on nectar from the flowers

What these small butterflies lack in size, they more than make up for in the sheer numbers that hatch, take to the air, and adorn almost every flowering plant in and around the fields at this time of year. It’s a spectacle, and one well worth a closer look. The Deer Lake meadows, at the western end of the lake, are a particularly good place to see the action, and enjoy what is by far our largest flight of butterflies in Burnaby.

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Purple vetch flowers are a favourite for nectaring skippers

Taking a closer look at these small butterflies, it’s noticeable right away that they’re not quite conventional butterfly shape. To some people they suggest moths, rather than butterflies. Their wings are more “swept-back” instead of being held either flat and open, or upright and closed, like “regular” butterflies. The hind wings are held out flat, while the forewings are held above them at a 45-degree angle – very rakish! They do at times, however, close both wings over their backs like regular butterflies. As you can see from the pictures, the open-winged stance is very common. This distinctive shape and stance shows that these butterflies are members of the grass skipper family.

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Skippers feeding (nectaring) on a dandelion – click to enlarge

So let’s take a close-up look. When you click to enlarge the photo above, you’ll see a couple of good clues as to why these insects are butterflies, and not moths. First take a look at the antennae which emerge from the head, angling outwards. They’re thin and thread-like with noticeable, club-shaped ends. In contrast, many moth antennae are feathery, and if they are thin like a butterfly’s, they lack the club end. Most moths are, of course, nocturnal, whereas these “guys” are active in the daytime. Two ticks for butterfly.

Now take a look at the skipper on the far right on the dandelion. You’ll see a third, thread-like organ emerging from the centre of the head, which then makes an angular curve downward into the flower. This is the proboscis, the hollow tube through which the butterfly draws up the nectar on which it is feeding. Now that you’ve looked at one skipper, a quick glance reveals that they’re all at it. This single flower is feeding a whole bunch of skippers.

Skipper Profusion

So what species of skipper are these? Well, thereby hangs a tale. These are European skippers. That’s right, they’re an introduced species from Europe.  First accidentally introduced to Ontario in 1910 they’ve spread across the country, and there have been many subsequent introductions since, including Duncan on Vancouver Island about 15 years ago. Ours could have spread from there, or they could have been introduced here separately. A particular aspect of the European skipper’s reproduction makes spreading to new locations very easy. And as usual, it’s we humans that are big contributors to skipper profusion, and skipper spread.

Unlike all native species of North American skippers, which overwinter as pupae, European skippers overwinter as eggs. This makes it very easy to survive being mowed, and then moved when hay is transported from one place to another. And hay fields is where skippers thrive. They’re called grass skippers because the larvae, the caterpillars, feed on grasses. As we can see, the adults get their food from flowers.

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European skippers feeding on clover

Although an introduced species, the European skipper is yet another example of a benign addition to our fauna. In this case, a very beautiful one too. There is no evidence that this introduced skipper has negatively affected our native skippers. It seems to have found a place here without causing problems for other species.

As John Acorn says in Butterflies of British Columbia  … we now have more butterflies on the wing than we ever could have without this cute little addition to our fauna. Here, here!

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European skippers – a welcome addition to our butterfly fauna