Wild Cat in the City – Another Sighting

Pedalling along Deer Lake Parkway bike path this morning on one of my frequent bike rides around Deer Lake Park, I heard a raucous “murder” of crows causing a real commotion ahead in the trees just off the roadside. Mobbing an owl? I wondered. Maybe another raptor the birds were taking exception to? Maybe an eagle?

Greeted with a loud chorus of caws, I stopped underneath the tree and looked up at the “lump” that was the centre of all that attention. Looking down at me was a bobcat.

People in cars driving by, people walking along the sidewalk all seemed oblivious to the cat and crow action above them.

And there was Bobby (or Bobbi) the object of all that fury.

Even a couple of Common Ravens chimed-in, adding their gruff cronks to the cacophony.

Raven, Crow and Bobcat

And a few minutes later a Red-tailed Hawk also took a fly-by look at all the action. Despite all the fuss, the bobcat was remarkably relaxed.

So relaxed, in fact, that he/she even took a couple of power naps.

What a beautiful animal!

For more information on our local bobcats check out my earlier post on this Wild Cat in the City.

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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.

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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.

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Wily takes a walk through my garden

 

 

 

A Blue Jay – the real thing!

Around these parts, many people name our local resident jays, blue jays. Birders like me feel a mild, internal cringe at this minor misnaming, but we usually let it pass without comment. After all, our birds are blue, and they’re definitely jays. The fairly common blue jay of our coastal forests is of course BC’s Provincial bird, the Steller’s Jay. Loud, brash, and with lots of attitude, it fits in well out here on the “left” coast.

Its somewhat shyer Eastern cousin is the real Blue Jay, and we’re incredibly lucky right now to have one visiting a backyard feeder regularly on North Gamma Ave, in North Burnaby.

Blue Jay #1

The real Blue Jay is a very rare visitor to the West Coast.

Common east of the Rocky Mountains and right across southern Canada, Blue Jays are rare visitors to the Lower Mainland, and as far as I’m aware this is the first one we know to visit Burnaby. It’s certainly a new addition to my list of Burnaby birds. Although rare in our region, Blue Jays are expanding their range in BC west of the Rockies. In fact, there is a second Blue Jay in south Vancouver right now. Two Blue Jays in one winter in this region is exceptional.

But let’s enjoy our bird. Compared to its cousin (shown below), the much more familiar Steller’s Jay, the Blue Jay’s blue is a lot paler, and the bird is much more boldly marked. Very similar in shape, size and structure, both birds are attracted to bird feeders and have a particular fondness for nuts of all kinds. Both members of the Cyanocitta genus, they are closely related, and where the two species are found together, they sometimes hybridize.

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Steller’s Jay, BC’s Provincial Bird

Blue Jay #3

Blue Jays sport many more colours than our resident Steller’s Jays. Various shades of blue make a showy contrast to areas of black, white, gray and taup – a handsome bird!

While both these birds show quite different shades or colours of blue, their blues have a fascinating connection. For the most part, wherever blue bird feathers are found, including our two jays here, it is not the result of pigmentation. In other words, the feathers are not coloured blue in the way blue jeans are, or blue cars are. At the microscopic level, their feathers have specialized structures that scatter the incoming light to produce the very precise blue colours we see. This is called structural colour. If you found a blue feather from one of these birds and held it up for the light to shine through it, it would look brownish. Here’s to structural colour – our two jays would be a lot drabber without it.

STJA#1

Dark blues and black predominate in the Steller’s Jays’ plumage.

So, if you’re heading up to North Gamma to look for the bird, focus your efforts north of Cambridge Street. A good clue will be other birders and photographers standing around waiting for the bird to put in an appearance. Another clue to the bird’s presence is its distinctive call. Listen out for it, as this bird frequently announces its arrival before putting in an appearance. And please be respectful of people’s homes and privacy.

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.

Calosoma and snail

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.

Carabus beetle

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.

Eurasian Collared-dove

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.

Eurasian Collared-dove

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.

BTPI#1

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.

BTPI#2

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.

EUCD#3

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.

COHAGroup

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.

COHA#1

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.

COHA#6

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.

COHA#4

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.

Deer Lake Heronry Flourishes

Within sight of Burnaby’s City Hall, the word is out that Great Blue Herons have constructed a huge and rapidly growing colony, and they’ve done it all without a building permit! It’s nesting season, and right now there’s so much going on in the colony at Deer Lake Park, it’s definitely time for us to get out there, take a look, and enjoy all the action.

BranchPluck

Great Blue Heron grabs a tree branch to add to its nest of sticks.
(Click to enlarge)

So head down to Deer Lake Avenue, opposite City Hall, to enjoy the sights and sounds. However, please watch only from the paths and the sidewalks. Entering the colony under the nests is definitely a No No. Peering in from the edges of the colony gives the best views of the birds, their nests, and all the goings on. Standing under the nests is unwise for many reasons, especially when looking up, mouth agape.

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Sticks are searched for diligently within the colony. or carried in from further afield.
(Click to enlarge)

Sticks are being gathered, nests built, nest sites squabbled over, and the occasional predator is vanquished. Egg-laying will start soon, if it hasn’t already, and after about 30 days incubation, the young will hatch. Following hatching, it takes another two months before the young fledge. And as the young grow, noise levels will rise, as will the colony’s strong, olfactory presence. Yes, it gets pretty stinky, and furthermore, later in the season the trees will be fully leafed-out, and activities harder to see. Now is a very good time to pay a visit.

Heronry

Almost 30 nests are visible here, most located in just two trees on the west side of the colony. (Click to enlarge)

For the past six years, much to the delight of park users, passers-by, interested scientists, and City and Ministry of Environment staff, the Deer Lake heronry has been growing in size at a fantastic rate. It has made a big jump in numbers this year. Don Jones, who, every season makes a very careful inventory of the nests, counted 104 in March. Last year (2012) the count was 66 nests – a whopping increase! As each nest represents a pair of herons, we now have over 200 birds using the colony. That’s a huge number of these big, spectacular birds.

So just how quickly has this colony grown? In 2008, I made the following notes about the heronry:

”There has been a small colony (2-3 pairs) of GBHE at the west end of the lake for the past 4 years. Last year (2007) the colony was predated by Bald Eagles, and no young were fledged. Up to three young were fledged, or were close to fledging in previous years.

This year the birds, presumably the same ones, relocated north and east of the previous location to a grove of black cottonwoods bounded on the south by Price St., on the north by Deer Lake Drive, and on the west by the trail that heads north-east diagonally from the foot of Price. In early May, three nests were visible with adults standing on and/or next to two of the nests.

On May 30, the leafing-out of the trees made observing the nests very difficult. Only the southern-most nest was fully visible, and an adult was sitting (presumably incubating) on it. The second nest was mostly concealed, and its top was not visible. The third nest was not visible at all.

Jul 02 visit. Two large juvenile birds (fully feathered) standing in and on the edge of the southernmost nest. The second nest seems to be unoccupied by either adults or young.”

So, from three nests in 2008 the colony has now grown to over one hundred nests. It seems that herons take note of which colonies are being successful, and will transfer to these new locations from others where conditions may not be as good.

CondoStyle2

Herons nest quite close together in the tall, 30 meter plus, black cottonwood trees. Separation of nests is governed by stabbing distance from those impressive bills. (Click to enlarge)

In fact, the transfer from another colony seems to be a likely cause of this year’s big jump in numbers. The Colony Farm heronry, visible along the Mary Hill Bypass in Coquitlam, has been abandoned this year, likely due to nearby bridge construction at the start of nesting season. The Deer Lake colony may well be attracting some of the birds from the Colony Farm heronry.

Bald Eagle incursions are also a problem for heron colonies. Bald Eagle attacks frequently cause colonies to be abandoned. Both the Deer Lake and the Colony Farm colonies have suffered from eagle attacks. However, Don Jones reported a very interesting observation at the Deer Lake colony this year. A Bald Eagle entered the colony, but was attacked strongly (pecked from above) by one of the herons. The other herons didn’t abandon, but just retreated a short distance. The eagle was finally driven away pursued by a heron. It makes me hopeful that perhaps the birds are learning strategies to defend their nests, even at this relatively early stage in the breeding season.

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Sticks are worked into place to build the nest.
(Click to enlarge)

LgeNest

Some nests are quite substantial structures.
(Click to enlarge)

Activities other than nest building are also taking place in the colony. Unfortunately, I didn’t manage to get a picture, but frequent copulations are happening. Despite that miss, I did, manage to capture some tender moments of mutual preening by a nesting pair.

Preen

Copulation, and mutual preening as shown here, both take place on or adjacent to the nest.
(Click to enlarge)

I was recently asked, if there are so many birds on the colony, how come we only see one or two in the park itself? Great Blue Herons will travel long distances (5 to 10 kms) to good feeding areas to forage. Watching the direction of birds flying to and from this colony suggests they are probably foraging along Burrard Inlet, and as far south as Boundary Bay. Both locations are within easy flying distance.

Some individuals do forage locally, and there are frequently one or two birds in Deer Lake Park itself. Some may not go as far as the Inlet or Boundary Bay. I managed to capture this not-very-good picture just a couple of days ago along Chub Creek, a tributary of Still Creek, of a heron just about to swallow its prey. I suspect it was fishing, but made this opportunistic capture instead.

WithVole

Great Blue Heron about to swallow a Townsend’s vole captured along the banks of Chub Creek.
(Click to enlarge)

It’s wonderful to have a such a success story on our doorstep, and we should celebrate our good fortune. However, we shouldn’t be complacent about the threats to the Great Blue Heron. We have a special, non-migratory subspecies here on the BC coast (Ardea herodias fannini), and it is designated a “Species of Special Concern” due to loss of wetland habitat in the Georgia Basin, and a declining population.

And not to be forgotten, too, is how this success story illustrates the importance of preserving the natural areas in our parks. In the 1980’s, the stand of black cottonwoods in which this colony has now established itself was designated for paving as a parking lot for the park. Thankfully, this City-inspired plan for the Park is long abandoned, and we now live in more enlightened times in Burnaby.

Thirty years ago this stand of trees was seen as dispensable. Today, completely unpredictably, it has become a significant colony for this threatened bird. A great example of why the precautionary principle is best applied consistently, especially to our natural areas.

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Great Blue Heron foraging at Deer Lake.
(Click to enlarge)

Let’s hope the success of our local colony will help us continue to enjoy these magnificent birds.

If you’ve been wondering why no posts lately, it’s because I’ve been travelling in South East Asia – birding of course. 

Posts should pick up to a regular pace from now on. Thanks for your patience.

George Clulow

Birds of a Feather….

…indeed do flock together. While many of our smaller birds in winter gather in mixed-species flocks to forage, and collectively keep their eyes out for predators, there are other species which, for the most part, stick with their own kind during the winter months. Perhaps the most obvious of these are our Northwestern Crows, which not only spend their days in extended family groups in their neighbourhood hang-outs, but return each evening to the huge communal roost along Still Creek. But there are others too, mostly smaller birds, that are notable for hanging out exclusively with their close feather-mates.

You’ve probably noticed the huge swirling flocks of Pine Siskins, small members of the finch family that are here in huge numbers this winter. Feeding on our native red alders, these flocks are almost entirely made up of the single species. Although occasionally, a few Common Redpolls or American Goldfinches may mix in.

Pine Siskin flock feeding in red alder.

Pine Siskin flock feeding in red alder

By far the largest flock I’ve seen this season, more than 800 birds, was swirling around the trees at the entrance to Deer Lake Park at Baffin Place earlier this week. I looked and listened, but as far as I could tell the entire flock was Pine Siskins – truly all birds of a feather. While mostly staying in the tree tops, sometimes these flocks move lower down to feed, and will even come right to ground level looking for food, or to pick up grit or small stones, which they swallow and store in their gizzards. If you don’t have teeth, a gizzard is evolution’s perfect solution for “chewing” food. The grit and stones are used in the muscular organ to grind up the bird’s food as part of the digestive process.

Pine Siskin on the ground looking for food or small stones or grit.

Pine Siskin on the ground foraging for food, or small stones or grit for its gizzard

Grit and small stones are not, however, the only reason for these birds to come to ground. Spending most to their time in tree tops, there comes a time for siskins to drink and bathe, and many in this huge flock were intent on both.

Here at Baffin Place, Third Beach Creek emerges from under Oakland St. and plunges deep into the forest as it makes its way into the lake below. A narrow, shallow stream, concealed in the forest is the perfect location for birds to drink and bathe.

Pine Siskins drinking along Third Beach Creek.

Pine Siskins crowding and drinking along Third Beach Creek.

And just like humans after a few drinks, the urge to jump in the hot tub is irresistible for some. In this case, the icy stream standing in for the warmer waters that we softies prefer.

Pine Siskins bathing along Third Beach Creek

Pine Siskins communally bathing along Third Beach Creek

Bathing itself is quite the explosive activity. In the centre of the “water bomb” below is a bathing, but invisible Pine Siskin. You’ll have to take my word for it.

Bathtime

Rapidly beating wings and shaking body produce an explosion of spray from this bathing siskin

After getting the feathers clean, it’s time to perch a little higher to carefully preen and get ready for flight, and to keep feathers waterproof.

After bathing the Pine Siskin preens the feathers into prime condition

A Pine Siskin preens its feathers into prime condition

Another of our familiar birds, the Bushtit, also flocks pretty much exclusively with its own kind during the winter months. This diminutive bird is related to chickadees, but not very closely, and is usually seen in flocks of from ten to thirty or so birds. Much easier to observe closely than Pine Siskins, Bushtits rarely feed in the tree tops, and are frequent visitors to suburban gardens where they will eagerly swarm the fat feeders put out for woodpeckers.

Is there room for me? Bushtits swarming a fat feeder

Is there room for me? Bushtits swarming a fat feeder

And not just one side.

Crowding both sides of the feeder, Bushtits eagerly eat the fat supplied for woodpeckers

Crowding both sides of the feeder, Bushtits eagerly eat the fat supplied for woodpeckers

Bushtit flocks are in almost constant motion, and will usually stay just a minute or two at the feeder before moving on. Sometimes one will stay still long enough to catch a solo picture.

Female Bushtits have yellow eyes, the males have dark eyes

Female Bushtits have yellow eyes; the males’ eyes are dark

Given their habit of flocking, it’s not surprising that Bushtits are very social birds, and this sociability extends beyond spending their winter days in together in feeding flocks. Come night-time and dropping temperatures, Bushtits will huddle in tight groups to maintain body heat overnight. In the breeding season, some populations of Bushtits have helpers at their nests in addition to the breeding pair – true birds of a feather.