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.

8SpotSkim#2Male

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.

8SpotSkimFem#2

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.

BlueDashMaleCrop

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.

BlueDFemCrop

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.

4SpotSkim

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.

BluetSp

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.

Red-flanked Bluetail? Really!

Even though I usually restrict this blog to Burnaby outdoors, there’s such an exciting story happening right now in New Westminster that I’m briefly stretching the Burnaby boundaries to encompass our Royal City neighbour. For the purposes of this story, New West becomes honorary Burnaby.

If you rush down to Queen’s Park right now, you can find a one of the rarest birds ever to show up in Canada. In fact, the Red-flanked Bluetail has never been seen before in Canada until yesterday. A single bird like this usually results in a flock of birders coming to see it. And they were arriving from around the Lower Mainland and Fraser Valley in flocks this morning.

Watching the Red-flanked Bluetail

Watching the Red-flanked Bluetail

And they were all here to see this:

Red-flanked Bluetail

Red-flanked Bluetail

But there’s a big backstory here. Last night I received an email from a birding friend who had seen a bird on Sunday morning that he just could not identify. Could I help suggest what he may have seen? If Colin couldn’t identify what he’d seen, I knew it had to be something really special. As soon as I read his notes and looked at his field sketch, I thought I knew what he’d seen. And the last ones of this species I had seen were in Japan! A quick flick through one of my Asian bird books confirmed my thinking: looks like a Red-flanked Bluetail. MEGA sighting. I sent the information off to another birding buddy who confirmed my hunch.

But, now we had to confirm the bird’s identity by finding it again this morning, and getting some photos if possible. And you know what the weather was like this morning – black ice and snow. I couldn’t believe it, on this of all mornings. The Birding Gods were seemingly against us.

I arrived at the children’s playground, just north of the petting zoo at daybreak – except day wasn’t really breaking, although my heart nearly was. Just the dimmest of dawns was struggling to emerge under dark skies and through steady snow. However, a movement caught out of the corner of my eye had me searching through the gloom. Nope – Song Sparrow. Then another movement, and HERE WE GO – an unmistakeable profile, but no plumage or other details visible, and just a struggle to track the bird as it flitted from tree base to tree base.

I couldn’t get a photo – too dark, the bird was too active, and where are the rest of people who should be here by now? A few better looks with some colour and detail were followed by guess what? Not only had my birding buddies not appeared, the bluetail had disappeared, and I still hadn’t had a really a good look to absolutely confirm the identity. It’s times like this that a birder’s stress levels really rise.

After half an hour of careful but frantic searching, my birding buddies appeared, but still no bird. And then, as though materializing from the snow itself, there was the bluetail. The light was better, the bird was close, and we could confirm the identity after finally getting a good look at the diagnostic white throat. Better still, Sharon’s a photographer too, and we got our confirming pictures for the record.

A couple of hours later the local birders were truly flocking in. We’d put the word out. An amazing number of people, it seems, had trouble getting to work this morning because of the roads, but the New West roads were magically much easier to drive, and people’s illnesses seemed very short-lived. Hmmm!

Let’s hope our tiny visitor from Asia hangs around a while longer. The word is flooding out across the birding universe, and visitors will no doubt be arriving from across the continent in the days ahead to see this ultra-rarity.

In the conditions this morning, my photos were poor. But here’s a couple more to round out the story.

Red-flanked Bluetail in children's play area

Red-flanked Bluetail in children’s play area

The bird looks extremely healthy, and is finding lots to eat. It consumed a large worm or grub while we watched, and it seems to be able to find insects, even in these conditions.

Red-flanked Bluetail finding food in snow

Red-flanked Bluetail finding food in snow

To find the bird, park or walk into the parking area at 1st Street and 4th Avenue. Head to the left into the forested North West section of the park. Look for the other birders, or look around the forest behind (west) of the children’s playground. The bird flies low to the ground , rarely going as high as 2 meters. Good luck.

For a much better pictures check out the following:

John Gordon’s blog at: http://thecanadianwarbler.blogspot.ca/

Mike Tabak’s Flickr page: http://www.flickr.com/photos/blackcappedlory/8385325240/in/photostream/

 

White-winged Crossbills Kick-start the New Year’s Birding

January 1st is the traditional day for birders to get outdoors and make a good, birdy start to the New Year. Have to get that “Year List” started! There’s a buzz of anticipation. And with many unusual and rare birds identified during the region’s Christmas Bird Counts, there are lots around to find. Whether starting a list of the birds in your local patch, or in Greater Vancouver, or even in the whole Province, New Year’s Day promises to get the lists off to a strong start. Can’t miss those winter rarities; you just don’t know how long they’ll stick around. Plus the benefits of a day in the fresh air after the season’s celebrations are a pretty good incentive too.

A foggy Deer Lake – New Year's Day, 2013

A foggy Deer Lake – New Year’s Day, 2013

If you’ve seen the movie The Big Year, you’ll know the extremes that some birders go to in pursuit of the ultimate Year List. But for me this year, I intended to take a more relaxed approach, and set some much more modest targets for my first day’s birding of 2013. Not for me getting caught up in the race to see everything, just to tick it off on the list. A nice leisurely breakfast, a resolve to take some pictures for the blog, and with the foggy morning, no great rush to get outdoors. I could start with the birds in the yard, and make my way by bike to Burnaby’s two main lakes to start a more constrained Year List.

Winter is the best time of year for a variety of ducks on our local lakes. The Bald Eagles know this too. Here’s an adult bird scanning the lake for easy prey; watching intently for any sign of weakness that may make for an easy capture, and a New Year’s Day meal.

Bald Eagle surveys Deer Lake looking for prey

Bald Eagle surveys Deer Lake looking for prey

Ring-necked Ducks are one of the species found on Deer Lake. Here, the dead-calm conditions of the foggy morning, and the clear reflections on the lake, allowed for a bit of photographic whimsy.

The rarely photographed 3-eyed Ring-necked Duck

The rarely photographed 3-eyed Ring-necked Duck

On the way to Burnaby Lake, along the east side of the rugby fields, Still Creek offered a couple of beauties. First, this spectacular Northern Pintail. More often out of camera range in the middle of the lake, this one allowed very close views.

NOPIMale

Northern Pintail – drake

Could we also call this slender, blue-billed beauty with the elaborate plumage the Irony Duck? I often think so. For many duck hunters this bird is a favourite target. It’s beauty makes for its appeal. How ironic then, that what’s beautiful makes it desirable to kill? And there’s a double irony at work here too. It’s those very same hunters who, in order to preserve their beautiful prey, contribute millions of dollars to the preservation of the wetlands vital to the breeding and wintering of this species. Irony indeed.

Pied-billed Grebe

Pied-billed Grebe

Not a duck at all, but another diving waterbird, the diminutive Pied-billed Grebe is another favourite of mine. In winter plumage here, but you can see a hint of what’s to come, and the source of the bird’s name, with the faint dots on the bill that will become black, and form a complete ring around the bill come spring time.

Burnaby Lake is probably our best location for closeup views of ducks. The Piper Spit boardwalk is a great place to hone your identification skills. Here’s a few I photographed on New Year’s Day.

Duck Common Goldeneye

Common Goldeneye – duck

Above is a Common Goldeneye female, which is a diving-duck relative of the much smaller Bufflehead shown below.

BUFFMale

Bufflehead – drake

Being a diving duck, the Bufflehead can forage in deeper waters than the dabbling ducks shown below.

WODUPair

Wood Ducks – duck and drake

The elaborately plumaged Wood Ducks are dabblers. Unlike diving ducks, dabblers rarely dive, but prefer to feed by upending in shallower water, as handily demonstrated below by a couple of Green-winged Teal.

Bottoms up!

Bottoms up!

On this year’s December 16th Christmas Bird Count (see previous post), our “best” bird was undoubtedly the White-winged Crossbills found at Burnaby Lake. And even better for starting all those New Year lists, they’re still around, and many local birders were out trying to add them to their lists. This is not a bird seen every year in the Vancouver area.  Red Crossbills are relatively common here, but the White-winged is a special visitor.

As I headed east from Piper Spit along the main Burnaby Lake trail to Conifer and Spruce Loop trails where the birds were being intermittently seen, I anticipated getting the usual view of crossbills – at treetop and distant. Walking toward the huge Sitka spruce tree (almost certainly the largest in the Park) just before the start of Spruce Loop, I spotted a photographer pointing her camera into the tree. And there, stunningly, some no more than 8 meters above the trail, was a flock of about 30 White-winged Crossbills hanging from the cones actively feeding.

WWCRFem#2

White-winged Crossbill – female

Avian nomads of the northern half of the Continent, crossbills wander the immense coniferous forests in large flocks looking for the cone crops they depend on for food. Using their crossed bills to wedge open the cone scales, they extract the highly nutritious seeds with their tongues. Individual birds can consume up to 3,000 conifer seeds in a day. Click on the images above and below to get a closer look at the highly specialized bills of these birds.

White-winged Crossbill – male

White-winged Crossbill – male

Crossbills are also notable for breeding whenever there is a quantity of food sufficient to support the development of eggs and the raising of young. The consequence being that they can breed at any time of year, and frequently do, even in the depths of winter! These birds, however, are unlikely to be breeding. What we’re seeing here is part of a broader search for food this winter among many different species of finches, and a likely indication that more northerly cone crops are low.

What a great kick-off to the New Year’s list. And if I can see White-winged Crossbills on January 1st, who knows what I might see if I chased a little harder. Hmmm!

Happy New Year.

If you want to check out the crossbills yourself, walk the main trail east from Piper Spit at Burnaby Lake, and explore the area around the Spruce and Conifer Loop trails. There are lots of Red Crossbills around too, and the two species are sometimes in mixed flocks here. Take your binoculars, and look up and listen for their distinctive flight calls:

Click here for White-winged Crossbills, and here for Red Crossbills.

Still Creek – Urban Wild, Birds and Poetry!

Over many years, Still Creek has been trashed; it’s been abused, polluted, buried underground in culverts through much of its course in Vancouver; had its banks channelized and stabilised, and its valley mostly built upon. It’s the Rodney Dangerfield of our urban waterways – [It] don’t get no respect!

Flowing mostly above ground in Burnaby and open to the sky, it is nevertheless, a highly urbanized stream – not a the first place one would of think to go looking for wildlife and nature. But yesterday, a quick look along the stream east of Gilmore made me determined to take a closer look today. I planned to travel from its mouth, taking pictures along the way, while following it upstream, staying as close to the watercourse as possible, and finishing my journey where Still Creek enters Burnaby as it emerges from under Boundary Road.

This morning, bright and early, I was at the creek’s mouth where it empties into Burnaby Lake. A frosty start to a mostly dull day, I began my biking and birding route enjoying the pleasant winter scene below, with the promise of an interesting morning’s birding.

Greater White-fronted Geese are a fairly rare bird in Burnaby, at least on the ground. We get huge flocks flying high overhead in wonderful undulating chevrons in late summer, but they’re headed for points south: Washington and Oregon, and then on to California. Only the occasional bird stops here. So, I was pleasantly surprised to see six immature Greater White-fronted Geese grazing on the rugby fields at the west  end of Burnaby Lake. What a good start.

The Greater White-fronted is smaller than our resident Canada Geese. The picture below shows a nice size comparison to its larger cousin.

And here’s a close-up showing the orange legs, orange bill, and the dark face with just a hint of the white at the base of the bill that will be much more extensive when this bird is an adult.

Carrying on upstream, in a mostly westward direction, my route along the Central Valley Greenway became steadily more urbanized and built-up, but still allowed views of the creek from the numerous bridges that span it. But there were plenty of brushy areas, and small stands of trees that were holding an amazing number and selection of birds.

In winter, many small birds forage and travel in mixed flocks, and it’s possible to see eight or more species in one small patch of bush and trees. A regular member of these mixed flocks is the Downy Woodpecker, pictured above.

Below is a Dark-eyed Junco, another flocking bird that frequently mixes with other species.

Also a member of these mixed flocks is the tiny Brown Creeper. Today I was lucky enough to get a sequence of pictures showing this bird’s foraging technique. They’re perpetual motion machines, and with the poor light this morning, the pictures aren’t perfect. These birds are never still.

Here’s the Brown Creeper creeping (what else?) up a dead snag.

Here it’s probing with that long curved bill looking for whatever may be holed up under the tree bark against the cold weather.

Bingo! Capture! A spider, I think, and very quickly dispatched.

Fox Sparrows and Song Sparrows are common throughout the city in parks, gardens, and anywhere where beautiful thickets of Himalayan blackberries are established. Although the blackberries are non-native, and disliked unfairly by many, they provide some of the best dicky-bird (birder talk for small bird) habitat we have, especially in disturbed sites.

Above is a handsome Song Sparrow – a common resident species here. Note the striped face, and particularly the grey stripe above the eye which widens at the rear of the head.

Above is probably my favourite sparrow to spend the winter in these parts, the Fox Sparrow. I know it’s another LBJ (more birder lingo: Little Brown Job), but this guy’s really got attitude. I think you can see it in the above picture. And doesn’t it look just great among the red-osier dogwood stems?

In fact, I like Fox Sparrows so much I couldn’t resist showing a second picture I took today. Just look at this perky bird.

The quick and easy way to tell these two LBJ’s apart is to look at the head and face. Where the Song has stripes, the Fox has a mostly plain, unstriped head and face, plus a two-tone bill. The lower mandible is yellow, contrasting with the more horn-coloured upper mandible.

On the stretch of the Central Valley Greenway shown below, Still Creek is to the left, but inaccessible,  and mostly not visible from the path. It’s an urban landscape, but the bushes and trees are full of life – real Urban Wild.

And it gets increasingly industrial as you head west.

Here’s where your compost and garden waste bin contents get unloaded after being picked-up curbside, before they’re shipped off to Delta for composting. But even here in this industrial setting, the gulls, arch scavengers that they are, have discovered a food source, and are performing some clean-up functions even before our waste has been shipped-out.

The birds feeding here are about 50:50 Glaucous-winged Gulls, and Glaucous-winged Gull hybrids. I won’t get into gull hybridization here; I might lose my readership!

Continuing west, and finally getting back creekside between Willingdon and Gilmore, here’s a picture of one of the things that caught my eye yesterday, and set today’s adventure in motion.

A beautiful drake Green-winged Teal (left) and a drake and duck Mallard loaf in the middle of Still Creek. Both duck species are quite common along the creek, and are particularly easy to observe along this stretch.

Also making a home here, is at least one Great Blue Heron. I saw one today, and managed to get the picture below yesterday of this one (same one?) perched treetop.

Of course, this stretch of the creek is the site of the famous Burnaby crow roost, where 10’s of thousands of birds fly in each evening to spend the night. And there’s plenty of evidence of their presence, both olfactory and visual.

And on the final stretch, heading toward Boundary Road with the creek invisible to the left, we’re in the full concrete jungle. But even here someone, a guerilla poet I suppose, is thinking of the natural world amidst the bustle of the everyday. Stencilled neatly on the sky train supports, just at eye-level, the poem unfolds as one walks, or cycles to work.

And so it starts:

Each morning

We fly

To work

Steady steps

Spinning wheels

Till like the crows

We return

To roost

How appropriate. How marvellous. Like Still Creek itself, this most urban part of the city has its life and liveliness, and poetry too.

***

To see a full list of birds I saw today, click here – Thirty species – a good count for such an urbanized location.

All photographs in the above post were taken along the Still Creek corridor today and yesterday.

Sign of the Times for the Salmon

With new signs posted to tell people to not harrass the fish, but instead to let them get on with reproducing, the chum salmon continue spawning in Buckingham Creek, and are drawing groups of the curious to watch the action. Good thing too it seems; someone was wading in the creek on Friday trying to catch the fish by hand! Let’s hope the fool didn’t do too much damage to the small spawning area these fish are using.A number of the people watching the salmon here have been asking where the fish are coming from. Well, they’ve had quite the journey. After spending a relatively short time in freshwater, the chum fry migrated to the Pacific ocean where they grew to maturity returning to their natal stream 3 to 5 years after departing.Their route back to Buckingham Creek and Deer Lake is quite the trek. From the ocean, the mature fish swim up the Fraser River, then turn into the Brunette River, and continue up the fish ladder past the Cariboo Dam, through Burnaby Lake, and then up into Deer Lake Brook crossing under the Highway 1, and Canada Way until they finally enter into Deer Lake, and up Buckingham Creek where they are attempting to complete their life cycle.

According to people I’ve spoken to at the creek there was a significant return of fish to spawn on Buckingham Creek about 15 years ago. Are these fish we’re seeing now a struggling remnant of a generation of fish hatched here back then? After all Paul K commented on the previous post that he saw a dead adult here in 2009. Has this population of fish been struggling along at small numbers for all these years, largely unnoticed or completely unnoticed? Or are these fish the returning adults of fry released by an elementary school child 3 to 5 years ago? Comments on the first post about these salmon have noted that school programs raise fish in classroom aquaria, and then the students release them into the local streams.

If you look closely at where the salmon are now spawning, a few stray eggs can be seen atop the gravel. Milky-coloured, these eggs are dead, but beneath the gravel, let’s hope there are probably viable ones. Signs of the times indeed.

Spawning Salmon – Buckingham Creek

Upon hearing reports of spawning salmon at Deer Lake this afternoon, I rushed down to the east end of the lake where, in fading light, I managed to watch several chum salmon (I couldn’t get a good count) actively working the gravel of Buckingham Creek in an attempt to build a redd in which to drop their eggs, and fertilize them.

Salmon spawning on the edge of a residential street, right next to the children’s swings in the playground must rate as some kind of ultimate trick and treat the day after Halloween!

All I could see at first were pale shapes beneath the creek’s dappled surface.

While listening to the slap of tails, and swooshing of water, the ghostly figures soon resolved into the recognizable shapes of salmon.Finally, I got progressively better looks, and was able to recognize them as chum salmon, one appearing to be more than 70 cm long.

More splashing action was followed by more waiting, until swimming near the bank one of the fish came into full view, its back above the surface.Over the many years I’ve enjoyed Deer Lake Park, this is my first sighting of spawning salmon here. Maybe I’ve missed something in previous years. After all, being a birder I’m always looking up, rarely down. However, there are a number of reports of other chum salmon returns to Burnaby waterways such as Byrne Creek, and Stoney Creek. See Burnaby Now reporter Jennifer Moreau’s blog.

Byrne and Stoney Creeks annually have spawning salmon. I’m not sure if Buckingham has been a member of that exclusive club in recent years. If not, maybe it’s time to think about doing some stream rehabilitation at Deer Lake too. Salmon in the city just has to be worth some effort. After all, the fish are clearly trying hard.

I’ll do some more research to see what I can find out about salmon at Deer Lake, and update this post next week.

Rusty Blackbird Triple Bonus

Wherever a rare bird puts in an appearance it’s likely to quickly draw a crowd, especially if it’s easy to access, and near an urban centre . The Rusty Blackbird that showed up on Friday at Piper Spit on Burnaby Lake fit the pattern perfectly. News of the bird was soon flying around (couldn’t resist that pun) the birder and photographer networks, and people were headed down to the Spit from around the Lower Mainland: Vancouver, Surrey, and the Fraser Valley. Bonus one – the Thanksgiving weekend gave people time to make the trip to the lake.

So what’s the big deal? Well for birders it is a rare bird, meaning it shows up most years in the Lower Mainland, but in single-digit numbers, frequently one or two only, and often for just a day before moving on. In birder parlance, they’re usually one-day-wonders. Hence, the rush by many to see and photograph the bird, before it left. Last year the same species showed up here at Piper Spit, and it was a one-day wonder. Many people missed it, including me. Bonus two – the bird has been here for at least four days.

While a few rustys show up in the Lower Mainland most years, nearly all Rusty Blackbirds winter in the south-eastern US, along the Atlantic Seaboard to Florida, and throughout much of the eastern drainage of the Mississippi. So our Burnaby bird is quite far out of range for the species in fall/winter.

Its breeding range, however, is quite different; it stretches right across Canada, east to west, and extends into Alaska. The birds breed in muskeg, bogs, beaver ponds, and wet, boreal forests as far north as the tree line. A real Canadian, eh? It’s the most northerly breeder of all the blackbirds, which is why it’s something of a mystery bird. It’s little studied because of its mostly remote summer haunts,  and its breeding biology is poorly known.

Compounding the mystery of its life cycle, is the mystery of its rapid decline over the past thirty or more years. Although some sources suggest we simply do not have enough information to draw definitive conclusions about the population changes of this species, there are many experts expressing concerns. For more information about the declining population of the Rusty Blackbird click here.

Locally, however, but having no bearing on its continental population, is some good news. Bonus three: a second bird turned up on Monday. There are now two Rusty Blackbirds at Piper Spit. To get one rare bird is a treat, but to get a second hanging out with it, is a wonderful happenstance. And even better is that these birds are very tolerant of people, and provide really good opportunities to observe them. When they do show up in the Lower Mainland, Rusty Blackbirds are usually skittish, and difficult to observe.

So head on down to Piper Spit and check out the new arrivals. They’re very cooperative, and show off their rusty-coloured winter plumage beautifully in the sun.

Owl Alert Flash Mob

Well, maybe not exactly a true flash mob, but certainly the avian equivalent was in full swing as I left the house yesterday morning. Stepping into the garden before setting off on a birding walk around Deer Lake, I was immediately aware that something was up. In the trees behind the house, a very agitated flock of small birds was calling and scolding and acting very excitedly. Such a mob scene usually indicates a predator is present, and often it’s an owl.

The centre of all the action was a western redcedar tree where I soon located the target of all the excitement and distress – a Barred Owl perched about 15m off the ground, staring down with its large, dark eyes as I made my way toward it. I could almost imagine its irritation at me now joining the mob. It was having enough trouble with the chickadees, nuthatches, kinglets, and robins that were kicking up a racket all around it.

Mobbing, as this behaviour is called, is practised by many birds. In forested areas, it’s mostly small birds in mixed species flocks like yesterday, and sometimes in single species flocks that gather around a predator in an attempt to drive it off, identify its location for other birds, and perhaps teach younger birds to recognize predators.

Chickadees are frequently the noisy instigators, and other birds join in. Some keep their distance, while others will actually fly at the bird to peck at it in an attempt to get it to move on – a risky strategy. Sometimes it works, and at other times the predator hangs in until the excitement subsides. Yesterday’s mob was successful. When I returned a couple of hours later, the owl had left.

In open areas, and frequently in nesting season, crows, blackbirds and swallows are often the lead mobsters, and their targets are our resident Red-tailed and Cooper’s Hawks.

Yesterday’s flash mob didn’t require texting, or social media to organize, just a group of noisy, frenzied birds to send the message out through the woods for others to join in, and get that owl out of there. As you’re walking our parks, listen out for these noisy gatherings. It’s not always an owl that’s the target, but sometimes cats, raccoons and squirrels will prompt the same behaviour.

For a full list of birds I saw around the lake yesterday click here.

The observant among you may notice that the owl picture above was not taken in a redcedar tree. I couldn’t get a good photograph yesterday; it was just too dark for my camera. I photographed the owl pictured above this spring, less than 50 m from the site of yesterday’s action. It could well have been the same bird. There is a pair in residence in the area.

Was Kermit wrong?

The two juvenile Green Herons that turned up at Piper Spit on Burnaby Lake yesterday morning are calling into question the truth of Kermit the Frog’s well known lament, It’s not easy being green. Watching these two young birds catch ‘minnows’ at the mouth of Eagle Creek, swallow one after another, and then follow-up their feasting with an extended period of preening in the surrounding trees, suggests the more appropriate song would be Summertime and the Livin’ is Easy – even if you are green.

Green Herons, the second smallest of the herons in North America, are at the Northern limit of their range in Southern BC, but can be found throughout the Americas, as far south as Venezuela where suitable wet, marshy habitats provide them with what they need to find cover, eat and reproduce. They are very uncommon in these parts, and only rarely will one spend the winter here.

Compared to the much more common and more familiar Great Blue Heron, Green Herons weigh in at around 210 g (7 oz) with a wingspan of 66 cm (26 inches), while Great Blues weigh in at a comparatively whopping 2.4 kg (5.3 lbs) and a have a wingspan of 1.83 meters (72 inches).

Green and small they may be, but they’re super efficient hunters. That sharp, pointed bill is used to deadly effect when hunting fish, their main prey, but it is no less effective when taking various insects and other invertebrates which also make up their diet. In common with all herons, their forward-angled eyes give them 3-D vision for pin-point accuracy.

Being dwellers of marshy lakes and other wetlands, other prey is also available. Below is one that escaped…

only to be recaptured… Yikes!

and finally to meet its end.

Oh dear! It seems Kermit was correct after all.

Well, everyone has to eat.

The three action photographs above were taken by John and Sheila Linn who are ardent photographers of nature in Burnaby. They capture many wonderful images of the wildlife and drama in our city’s parks. Thank you, John and Sheila for this wonderful sequence.

And a final note about the birds: both Green Herons still have some residual natal down on their heads which suggests they are local birds, born and bred on Burnaby Lake, or more likely along one of its tributary creeks.

And a final note about Kermit’s brethren above: the frog that became lunch for one of the herons is a non-native species, a Green Frog. Along with Bullfrogs, which are also common in the Lake, they are wreaking havoc with our much smaller native frogs, by outcompeting them and frequently eating them. So let’s hear a cheer for the herons, doing their bit to control introduced species.

Fall Fog Fest

You might call it Indian summer and love it, or you might lament that this marvellous stretch of weather we’re having comes when most of us are heading back to school and to work. Too bad we can revel in it only on weekends, whereas Monday to Friday doesn’t leave much time. And worse still, the special foggy piece that comes along with the weather is very easy to miss. This fleeting phenomenon, like so many of the great things happening in our parks, is best seen in the early morning.

Our weather forecasters certainly love this weather. It’s their time of the year to get the forecasts bang-on correct. They deserve it. Let’s face it, being a meteorologist here on the West Coast can’t be much fun for most of the year. No fronts sweeping in off the Pacific, just day after day of ‘sunny tomorrow, and the day after, and…’ . An end-of-summer high pressure system has settled over the Coast, and is bringing us cool nights, warm days, and day-long blue skies and sunshine. However, just as the sun breaks over the horizon in the morning, our parks are magically transformed by fog.

With clear skies overnight, the ground radiates its daytime heat right back into space – no clouds to provide a warming ‘blanket.’ The result: the air closest to the ground is cooler than the air immediately above it, and the moisture in that cooler air condenses forming minute droplets – fog, technically speaking, radiation fog.

You can see it at Deer Lake,

and Burnaby Lake,

but only briefly. The sun rapidly burns off nature’s transformer, and we’re back to clear landscapes, and no hint of what was there minutes before.

Not only does this fog fest depend on where you stand (low areas are best), but interestingly it depends too on where you look in relation to the sun. If you look toward the sun, much of the light is dispersed through the airborne water droplets making the fog visible,

but when you look at a more oblique angle, the fog just about disappears.

The two pictures above of the foggy doggy walker were taken less than 30 seconds apart. The fog really didn’t change in that time, but my angle in relation to the sun did.

So check it out. Take a few minutes if you can on your way to work or school to take a look. Right now the best time is right around sunrise, and the event is pretty well over in an hour. If you’re late for work, say I said it’s OK. Sorry, but I can’t give permission to be late for school. You’re on your own for that one!