Sad End for First Breeding Record of Sandhill Cranes in Burnaby

As I was about to publish the post below, I heard that the good news story that had been unfolding all last week at Piper Spit on Burnaby Lake had come to a sad end. The Sandhill Crane chick (colt) pictured below is no longer with its parents, and has likely died from some unknown cause.

To document the cranes’ story I have decided to let the original post stand, with some slight modifications, because it’s such a good story, and worth telling. While many will consider the outcome a local tragedy, it does illustrate how precarious life can be in the wild, especially for young animals. Survival rates are often low.

Let’s hope the cranes nest again next year. There’s a good chance they will, and we can all hope for a better outcome.

Original post written July 5/6, 2015

The risk with a post like this is that the story gets buried in the overabundance of cute at its centre.

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Sandhill Crane chick and adult (June 27)

Now I’m not denying (how could I?) the cute factor here , but the story is the historical first that this new arrival represents, and the cute needs no elaboration from me. Just look at the pictures.

And while the chick may be the epitome of cute, let’s not overlook that we’ve got one of the Lower Mainland’s most majestic and uncommon birds breeding right here at Burnaby Lake for the first time since we’ve been keeping records. And they’re putting on a show for everyone.

How do I know these birds have set a breeding record here? A quick search of the literature shows that this new arrival is the first record ever record of breeding Sandhill Cranes at Burnaby Lake, and anywhere else in Burnaby for that matter.

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Sandhill Crane chick and parents (June 26)

The chick pictured above, the first day I saw it, is just a few days old, and was being fed and guarded by both parents. Watching it, I was surprised to see it was picking at and eating some food items independently, which is notable for such a young bird. Usually the parents supply all its food requirements at this early age. After their natal down has dried, and within 24 hours of hatching, Sandhill Crane chicks leave the nest permanently. Such behaviour defines these hatchlings as nidifugous (Sorry, couldn’t resist such an unlikely word), and then they’re off on the risky journey to adulthood.

Sandhill Cranes are rare breeders in only a few locations in the Lower Mainland/Fraser Valley. The wetlands south of Pitt Lake in Maple Ridge were their breeding centre for many years, with just a few pairs actually nesting there. A few more bred in Langley. We do see large flocks of Sandhill Cranes in the Lower Mainland, but only in migration – spring heading north and fall flying south. For the most part these birds continue on their migrations and we are fortunate to see them when they pass over.

However, over the past decade or so, a small breeding population has established itself at the Reifel Migratory Bird Sanctuary in Delta. Birds, likely from that population, have been turning up in Richmond, where they started to breed about five years ago (first time since 1946), and they’ve also been showing up on our local golf courses, where they haven’t nested, perhaps from dodging flying golf balls!

Sandhill Cranes at Reifel Migratory Bird Sanctuary, Delta

Sandhill Cranes at Reifel Migratory Bird Sanctuary, Delta

In British Columbia, Sandhill Cranes breed mostly in the Central Interior (Northern Okanagan and the Cariboo/Chilcotin, with some breeding in the north east (Fort Nelson area), and others on the central coast islands and Haida Gwai. Breeding in the Lower Mainland is much less common.

Sandhill Crane chicks grow rapidly, and “our” Burnaby bird seems to be doing just that. Compare the picture taken June 26 with the one here below taken July 5th. Junior is gaining height and bulk, and both parents are supplying it with food.

Chick and parents, July 5

Chick and parents (July 5)

Unlike many birds that spend their first weeks in the nest, nidifugous birds are incredibly mobile for such young animals.

It can wade, even on its junior-sized legs.

 

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It can swim.

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It can run.

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It can preen.

Or, it can simply look disarmingly cute.

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Sandhill Cranes have been showing up irregularly at Burnaby Lake for the past few years. This year they clearly stayed to breed.

Between one and three eggs is the usual clutch size, with two being typical. One or two young are usual. Both parents incubate the eggs, although the female does the overnight shift which means she does about 70% of the incubation duties. Once the chicks leave the nest, both parents protect and feed the young.

SACR BbyLFed#5

Sandhill Cranes are monogamous and tend to maintain pair bonds over many seasons, especially if they successfully breed together. So barring accidents, this pair may be together for the long haul.

As to which is the male and which the female, the birds know of course, but the sexes are similar and not separable by appearance. During their courtship displays though, the males and females can be identified by their specific bugling calls and head motions.

Postscript

I headed down to the lake this afternoon (July 6) to confirm the reports of the chick’s disappearance. Sure enough the two parents were there, occasionally bugling quietly, but no chick was in sight. Given the birds’ extreme attentiveness to their young, the conclusion has to be that the youngster is dead.

It was apparently showing some respiratory distress yesterday which got progressively worse during the day. The chick was nowhere to be seen this morning. A sad ending, but there is hope for next year.

Pair

Pine Grosbeaks – Burnaby Mountain Park

It’s not every winter that Pine Grosbeaks show up at lower elevations of the Lower Mainland. But what a treat it is when they do.

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Pine Grosbeak, male

The beautiful male shown above is one of a flock of at least fourteen birds that are providing a show for visitors to Burnaby Mountain where they can be found feasting on the buds of the flowering cherry trees that line the path south of Horizon’s Restaurant.

In the West, this large member of the finch family is usually found in the coniferous forests of the mountains where it breeds. More commonly seen in lower elevations in the Interior, it only rarely puts in an appearance in coastal areas of southern BC. These irregular movements to lower elevations are called irruptions, and are perhaps related to changes in food supply, but like many aspects of this species’ life, the phenomenon is poorly understood.

Found across the continent, mostly in Boreal Forest regions, the Pine Grosbeak’s range also extends to Eurasia where it is found from Eastern Asia to Scandinavia. Despite the wide geographical range of this species, it’s likely that the different populations do not wander very widely from their home territories. Our visitors to Burnaby Mountain have likely not travelled great distances to get here.

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Pine Grosbeak, female

Males and females are very different in appearance. The females’ colouring is more subdued, a subtle mixture of grays and greenish gold. This cryptic colouration is no doubt important during nesting, when the female is the only one of the pair to brood the eggs and chicks. Both parents, however, share in feeding the young.

While the males and females in the flock are easy to pick out, there are also a couple of differently plumaged individuals in the flock. The one below shows a lot of red on the head and neck in an otherwise female plumage. This individual may be a first year male, not yet fully red, or a female that is more colourful than is typical.

PIGRimm?

Female or first year male Pine Grosbeak

Given these birds live mostly in inaccessible mountain forests, it’s perhaps not surprising that they tolerate close approach by people. It appears they do not see humans as potential danger. If you pay a visit to the cherry trees on the mountain, make sure you take a camera or binoculars. Move slowly, without sudden movements, and you’ll be rewarded with close views of the birds unconcerned with your presence. You will get the opportunity to see some of their more subtle features in close-up, for example the striking back pattern on this bird.

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So enjoy them while they’re here; it may be many years before we see them again.

PIGRmaleClose

 

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

 

Bobcat!

We’ve got salmon returning to our creeks once again, the coyotes are still howling at the passing emergency vehicles, and for the past few months, we’ve had a bobcat active in Deer Lake Park. This is life in the city that’s really hard to equal.

BobcatRevI’ve been waiting eagerly for a couple of months now to make this post. Bobbie (gender unknown), has been putting in regular appearances throughout Deer Lake Park, and during the summer was a regular in my neighbourhood on the park’s southern edge. But I couldn’t get a picture! In fact, for more than a week, I hadn’t even seen the feline when everyone in my household and many of my neighbours had – frustrating, even for a bird guy.

Without a picture, how could I make a decent blog post? Then finally, a visitor from Taiwan, Paul Chen, took the wonderful image above. Thank you Paul, for allowing me to use it here.

It’s probably a surprise to many readers that bobcats and humans can live so peacefully together. It’s remarkable what happens when we don’t persecute our wildlife, and we provide some habitat in which to make a living. This is a tribute to “untidy,” wilder parks that have habitats as close to “natural” as we can manage in the city. The payoff is huge. Keep Burnaby green (and a bit scruffy around the edges, please).

CatSignClse

 

Not that we haven’t had Bobcats in the City previously; I know of reports going back to at least 2009 at both Deer Lake and Burnaby Lake. But we urban dwellers are not used to seeing the larger species of North American wild cats, and we’re certainly not expecting to see them in the city. So, if surprised by one, we often jump to the wrong conclusion – cougar!

As you can see from the above signs posted this fall in the park, park walkers were confused as to the identity of the large cat many had seen. City staff attempted to put people at ease, and so posted a number of the above signs. However, it’s hard to win when you’re trying to put people at ease. Some people interpreted the signs to indicate there could be a cougar in the area. Oh well!

A close look at the real bobcat picture above shows that the one living here does not quite fit the silhouette shown on the sign. Our Bobbie is proportionally longer legged, and generally more slender. However, the short, black-tipped tail is diagnostic for the species. A bobbed tail gives it its name – bobcat.

Bobcats are carnivores, and the literature suggests rabbits and hares are favourite prey, neither of which is common in Burnaby. When the cat was active in my neighbourhood it was feeding on gray squirrels and its hunting technique was interesting.

BobcatPrey

Remains of bobcat prey – a gray squirrel tail and foot

My neighbour’s apple tree is always a favourite source of food for the squirrels in the fall. If you’ve ever watched a squirrel carrying a pilfered apple in its mouth, you’ll recognize that it must be seriously visually impaired. Bobbie would lie in wait and pounce as Nutkin was about to leap the fence with its prize. Twice it was seen in the early morning carrying captured squirrels over the fence. It seems too that they were eaten out in open on the lawn. This is one relaxed bobcat. The apples, of course, were always left behind. No apple sauce with squirrel dinner for this predator. Since the Eastern gray squirrel is an introduced species, I am pleased that the population is feeding this beautiful, native cat.

It’s clear from our experience here that bobcats can live well on urban fringes, and this is being noticed throughout the continent. In Deer Lake Park there are plenty of Townsend’s voles in the meadows that would also provide food. As the picture above shows, perhaps bobcats would avail themselves of some salmon too if available.

They are beautiful, opportunistic predators that we are so fortunate to have living with us. However, they are wild cats feeding on whatever they can find so we have yet one more reason to keep our domestic cats indoors and to make sure other small pets are leashed.

C&CSigns

And as the sign indicates there’a at least one other predator abroad that should encourage us to keep our pets protected. Yes, it’s the coyote, the other large, four legged predator in our parks.

CoyoteGrdn

Wily takes a walk through my garden

 

 

 

Exploring Burnaby’s Parks and Natural Areas

Announcement

I’ll  be leading a walk for the City of Burnaby on Saturday, November 22 – rain or shine. The walk is billed as: Exploring the Still Creek Corridor & Central Valley Greenway.

We’ll spend about three hours walking the trails bordering Still Creek from where it flows into Burnaby Lake. Registration is required, and is limited to 15 participants. I’ll focus on the birds, of course, but we’ll keep our eyes out for all aspects of the natural world.

NOFL–display

The Northern Flicker is the most likely woodpecker species to be encountered on the walk. Here are two displaying adults from earlier this fall.

To register, go to the City’s website WebReg page and enter event number 350173 into the search box. The walk is not in the Parks and Leisure Guide as it was organized after press time for that publication.

There will be lots to see, and with the wet weather lately we may be lucky enough to find some interesting fungus like this bird’s nest fungus (how appropriate!) I photographed a couple of days back in Deer Lake Park.

Bird's Nest Fungus 2

Bird’s Nest Fungus growing on decaying wood.

The close-up below shows the still developing cups covered in a white membrane that will split away to reveal the egg-like peridioles held within.

Bird's Nest Fungus

Bird’s Nest Fungus growing through moss on a decaying log

Because I’m a birder and not a mycologist, I’m not able to tell you the actual species of bird’s nest fungus pictured here; there are many. Perhaps a reader can help.

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.

FeathersBeach

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.

CANG2

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.

CANG1

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.

CANG3

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.

CANGBathe

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.

MALLHead

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.

MALLAlt

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.

NOCRBeach

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.

LBDO1

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.

LBDOItch

****

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.

NOHAfem2HungHR

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.

NOHAgeomale2

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.

NOHAmaleflightHR

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.

Meadow sign

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.

NOHAfemaleHR

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.

NOHApairflightHR

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.

NOHApreyexchangeHR

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.

Our Dandiest Duck?

So let’s see: iridescent greens, blues, cobalt, purple, violet, bronze, ultramarine, crimson, burgundy spotted with white, black, and vermiculated gold; we could just as well be reading a list of exotic colours on an artist’s palette as descriptions of Wood Duck plumage – a dandy’s colours for sure. See for yourself; click on the image below.

WODU3pairWood Ducks frequently perch on logs, and tree limbs near the water

The females above are noticeably subdued in their plumage compared to the drakes, but being the sole incubator of the eggs, and the guardian of the young when they first emerge from the nest, it makes sense to be less eye-catching to predators. It’s all about remaining inconspicuous, and not drawing unwanted attention. This is a common evolutionary adaptation among many bird species, and among North American ducks nearly all species show this strong sexual dimorphism. Wood Ducks happen to be one of the species that push these male/female differences to the extreme. While it is the drakes that catch the eye on a first look, both females and males are worthy of close scrutiny that reveals the real complexity and subtlety of the colours of both sexes. Let’s start with a closer look at the females.

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Female Wood Duck – showing the diagnostic white eye-patch that tapers to the rear.

Most species of female ducks are relatively drab in colour, often a mixture of browns, buffs, and tans, but our Wood Duck above shows some iridescence both on the top of the head, and in the shoulder feathers (scapulars) spreading out below the neck. Taking an even closer look at the scapulars we see the subtle, but beautiful colours that we might otherwise miss when seeing a female perched alongside her fancier mate.

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Subtle but striking – the shoulder and some wing feathers of the female Wood Duck

Wood Ducks are unique among North American duck species. They are the sole representative on the continent of their genus, Aix (Greek for waterbird). In fact, the Aix genus contains only two species worldwide. The other is the Australasian Mandarin Duck – another contestant in the “dandy duck” stakes. Both are part of a larger group called the perching ducks. Wood Ducks certainly live up to that classification. They are often seen perching along the water’s edge on logs and in sometimes in trees.

Confirming their scientific classification as perching ducks, Wood Ducks line a tree limb over Eagle Creek

Confirming their scientific classification as perching ducks, Wood Ducks line a tree limb over Eagle Creek, loafing, preening and snoozing.

There’s a certain irony, however, to the dramatic sexual dimorphism we see in Wood Ducks. It’s the drabber females’ choice of mates that drives the evolution of the spectacular male plumage. Pairs are seasonally monogamous, i.e. they pair-up anew each year,  but because the males play no part in rearing the young (more “dandy” behaviour?) their breeding success is more strongly determined by their ability to attract a mate. Therefore, the bolder the plumage, which indicates to the female readiness and suitability of the male for breeding, the more chance the male has of being selected and passing on his genes to the next generation. Other species of birds in which the males do assist with rearing the young are frequently less sexually dimorphic. Here’s the drake Wood Duck.

Wood Duck male – Dandy indeed!

Wood Duck male – Dandy indeed!

The colours above need no more description, but it is worth noticing the rakish crest that flows down the back of the head. The female has one too, and among the dabbling ducks in North America (Mallards, wigeons, and teals etc), the crest sported by the Wood Duck is unique.

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This drake is perched next to a female, and is lifting his head to display to her the “full effect”.

The gradations of colours here on the head are quite striking in close-up. No doubt they’re just what an interested female is looking for.

Paired Wood Ducks

Paired Wood Ducks

And while all this fantastic plumage is in pursuit of one thing – passing on the male’s genes to the next generation, Wood Ducks also need suitable habitat to breed successfully – marshy lakes and ponds with lots of surrounding vegetation. Oh yes, and one more thing; they need nest cavities. Before the forests of North America were extensively cleared, and the old trees that contained natural cavities from broken branches and abandoned woodpecker holes were cut down, Wood Ducks were numerous. However, by the late nineteenth century there were real fears that the Wood Duck would go extinct from the combination of habitat loss and over-hunting. After the Migratory Bird Act of 1918 ended the legal hunting of Wood Ducks, the species recovered rapidly. Concerned conservationists also helped them along by providing nest boxes to replace the natural cavities that had been lost in forest clearing.

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Wood Duck nestbox – Piper Spit, Burnaby Lake

The best place locally to see lots of Wood Ducks is Burnaby Lake at Piper Spit, and it’s no coincidence that at this location you’ll also see many nest boxes put up specifically for Wood Ducks. Although there are many nestboxes at Burnaby Lake, there may not be enough for all the ducks needing one. There are frequent incidents of egg-dumping here when more than one female lays her eggs in a single nest box – up to thirty eggs in a one box. Now not all the eggs will hatch in these conditions, but for a female that can’t find a nest cavity of her own, it seems a good strategy to ensure that at least some eggs produced by the female will hatch.

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Glaucous Gull – A Rare Deer Lake Visitor

There is always a small flock of gulls that spend the winter on the beach around the children’s playground at the east end of Deer Lake, but this year more than the usual number has shown up, and they’ve been joined by a rare visitor from the Arctic.

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Gulls winging into the beach at Deer Lake

The birds come and go over the course of the day, but at times this month I’ve counted up to 300 on the beach and out on the lake – a good number.

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Adults and immature (the brownish ones) gulls on Deer Lake beach.

They come to the beach for a couple of reasons: one, they like to bathe and clean up their plumage at the mouth of Buckingham Creek where it flows into the lake over a gravelly bar. And two, because people come down to the lake to feed the ducks, often with the kids in tow, the gulls hang around to grab their share of the handouts. Of course it’s against park rules to feed the wildlife, but the happy result for us is that the gulls get quite used to people, and it gives us the chance to see them up-close and personal. And to identify gulls, good close looks are preferred.

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Spot the visitor?

If you take a close look at the flock, you’re likely able to pick out the one that is a little larger than the others, and looks a little different too. There are other brownish gulls on the beach, but the washed-out looking bird in the centre of the picture above is the Glaucous Gull, our rare visitor from the Arctic.

Here’s a close up.

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Glaucous Gull – Deer Lake beach

So what makes this one different? Isn’t it just another gull? Firstly, it’s large, and it’s by far the palest looking immature bird on the beach. There are other brownish birds, but this bird is basically a dirty-white overall with light brown markings on the back and wings. Its wingtips are virtually white. It has a large, heavy bill which is quite strikingly bi-coloured, pink at the base, and black-tipped.

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Bi-coloured pink and black bill, dark eye, and dirty white plumage are key features that identify this immature Glaucous Gull.

When Glaucous Gulls do show up in British Columbia it’s mostly as single birds. They are usually in their first or second winter of life, and our visitor fits this general pattern. The Deer Lake gull is a first winter bird. Glaucous gulls are among a number of large white-headed gulls that take four years to reach adulthood, and acquire their full adult plumage. This one has three more years to go.

The bird below is also a white-headed gull, but it’s quite a bit smaller than the Glaucous Gull, and takes three years to reach adulthood.

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Ring-billed Gull adult

I think the Ring-billed Gull is quite a nattily handsome bird and is the species most frequently seen down at the lake, and fortunately is also very easy to identify in adult plumage. The combination of grey back, black wingtips with white “mirrors”, yellow legs, yellow eyes, and a bold black ring on a yellow bill is diagnostic. This one is still in winter plumage shown by the dusky flecking over the head and neck. These brown feather tips will wear away over the course of the winter to leave a pure white head ready for the breeding season.

Gulls are difficult group of birds to identify, and I usually recommend for casual or beginning birders to leave them until later. Start with easy stuff. However, some birders get  “into” gulls in a big way; they get captured by the complexity of identification and the excitement of finding the rarities among the commonplace. However, it’s a challenge. The birds have different plumages in each year before they reach adulthood, with the immature birds being the most challenging to sort out.

As adults, most gulls show a combination of white head, neck and body, grey back or mantle, and dark wingtips with white “mirrors”. Many of the differences among species are subtle. And to cap it off, gulls of different species frequently interbreed, producing all sorts of hybrids with features of two different parents making identification even more difficult. There are lots of hybrid gulls in the Deer Lake flock. Here’s just one example below.

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Probable Glaucous-winged X Herring Gull hybrid

I could go on and on about gulls, but I fear my audience will soon be mimicking the yawn of the Glaucous Gull below.

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Glaucous Gull centre and Glaucous-winged Gull to the left front

However, one final suggestion for a common and easy-to-identify gull is the Glaucous-winged Gull shown on the left above. It’s a large gull, yellow billed, pink legged, and with a pale grey back and grey (not dark or black) wingtips with white mirrors. If the grey coloured wingtips match the colour of the back, you’ve got a Glaucous-winged Gull.

Glaucous, by the way, refers to the grey colour of the adult birds’ back, and wings. Adult Glaucous Gulls have white wing tips.

Gull numbers at the lake will drop steadily from now on. The Glaucous Gull will likely head back north, perhaps to Alaska. It won’t breed for another three years, and when it does, it will do so on Arctic breeding grounds. The Ring-billed Gull will head back to its breeding grounds that stretch across central BC, the Prairies and all the way across the country to Newfoundland and Labrador. The Glaucous-winged Gull breeds here on the BC coast, in Washington State, and right up to Alaska and the Aleutian Islands. It is our commonest year-round gull in Metro Vancouver and the Georgia Basin.

So you’ve hung in this far, thank you for your persistence. Gulls are not everyone’s idea of a fun topic. I’ve not posted for a while, but life just gets really busy sometimes. I plan to be posting more regularly as we head into spring. There’s lots to see and enjoy in our parks. Next up are Wood Ducks, our dandiest ducks.