reading the fine print

PHOTO POST

Who knew there was a Green Heron in our neighbourhood?

I’m sure many birders knew, but until this spring I didn’t know there is such a thing as a Green Heron, or that the Green Heron is hardly green at all, or that I had in fact seen and photographed a Green Heron a year ago.

More on herons later, but let’s agree that one can study and admire the fine features of many creatures while being quite unaware of their names.

Wingspan

The dragonflies that buzz around the reeds and lilypads at the edge of the marsh, for example, come in many colours, and might change their looks depending on the angle of the sun – but whatever their species, they are among the most beautiful sights on a steamy summer evening.

Stained Glass

The same can be said of Jewelweed (Impatiens capensis), whose delicate orange blossom would be as beautiful by any other name.

Jewelweed

But of course the details matter greatly in many ways. While the native Jewelweed is no more or less beautiful than the somewhat similar Himalayan Balsam (see previous post, Before and After Flowers), the latter, recently introduced species is unfortunately far too successful in this environment, with the result that it can quickly crowd out most other plants.

Frogbit One

The same is true of European Frog-bit, whose tiny and delicate white flowers are now popping up around the edges of Bowmanville Marsh. Brought in to an Ottawa area experimental farm in 1932 as a possible decorative plant, it began to colonize many other bodies of water and is now widely established in southern Ontario and some northeast US states. Unfortunately, its miniature “lily pads” soon multiply to great numbers that snuff out many other plants, and which also spread easily when moved by contact with boats or moving water including the wake from boats. (See Ontario government fact sheet on European Frog-bit)

Frogbit Two

 

Shore Lunch

On the other hand, the Turkey Vulture is one of our more majestic indigenous birds, though it has the unglamorous job of cleaning up carrion. (They do not eat fresh meat.) When Turkey Vultures glide on thermals over the beach they are a welcome sight, as that usually means there is a dead fish or waterbird sending a pungent odour heavenward, and the Turkey Vultures have arrived to deal with it.

Sharp Look

One of the inescapable facts of living on the lakeshore is that there are lots of spiders – thousands, millions, gazillions? They make a mess of windows and outdoor walls, and ensure that the first person to walk through a doorway in the morning can expect a spider web across the face. Most of them are too small to successfully photograph with the equipment I have, but this beauty, stationed on the gatepost to our vegetable garden, is an exception.

Garden Guardian

 

Night Heron by Day

A fine heron by any name

And now about those herons. The Great Blue Heron is unmistakable and can be sighted on most paddling excursions in Bowmanville and Westside marshes, but the small herons are more elusive.

Adult Black-Crowned Night Herons are fairly easy to spot, as their white body and black-cap head stand out clearly against the green reeds. The youngsters, though, wear a better camouflage. Though the adult Black-Crown Night Herons and Green Herons don’t look at all alike, their youngsters bear many similarities.

I first became aware of the Green Heron a few months ago, when I spotted one in the still-short fresh green reeds along Soper Creek. Following that sighting I tried many times to spot the bird again, with little luck. But by late July I started to see young small herons, and learned it is easy to confuse the Black-Crowned Night Heron with the Green Heron – they both have predominately brown and white mottled feathers.

The juvenile Black-Crowned Night Heron does not have a black cap, I learned, while a Green Heron wears a dark cap as both a juvenile and adult.

Looking at old pictures, I realized that in a post a year ago I had misidentified the bird at right as a Black-Crowned Night Heron, at a time when I wasn’t aware that Green Herons exist or that they might be found in this area.

At Roost

In the past two weeks I believe I have spotted juveniles of both species, though they are far more cautious and skittish than the Great Blue Herons. The youngster above, for example, retreated to a hiding place high in the trees beside Bowmanville Creek. It was only by drifting by very slowly that I found one angle with an almost unobstructed view.

And after many excursions at dawn and at sunset, I think I’ve finally captured a clear view of a Green Heron, below.

I Was Here All Along

Top photo: On An Arc (click here for larger view)

Disclaimer: the foregoing is not to be construed as advice from a certified authority, including but not limited to, ornithologist, entomologist, arachnologist, angelologist, ichthyologist, neuropsychopharmacologist, lepidopterologist, numismatologist, phytologist, dendrologist or other ologist, and is accompanied by no guarantee, either express or implied.

before and after flowers

PHOTO POST

With most summer flowers now fallen away or drying, it is up to butterflies and damselflies, grasses and fruits, to provide flashes of colour. While monarchs are drawn to the late-blooming Silphium, their caterpillars chew through Milkweed leaves.

Perspectives in pink (click images for larger views)

A wide variety of dragonflies and damselflies drift across from the marsh to our gardens – and clearly, for them this is a busy time of year.

Freefloat

 

Stars Came Out

 

Orange arrangement

Some of this season’s lilies are strikingly colourful even as they dry in the sun, and a few are still attracting pollinators.

Firedust

 

Listening Post

But sometimes you want to escape the heat. This rabbit relaxes on the beach in a cool morning breeze, having earned a break after a long night of pillaging gardens throughout the neighbourhood.

Coming-of-Age Story

On Westside Marsh, a trio of Mute Swan cygnets now look almost grown up, though their grey bills and mottled grey feathers still set them apart from their parents.

Under the Canopy

The flowers that are just now coming into bloom tend to be very tall. At two metres or more, the Himalayan Balsam is a good bit taller than its native cousin the orange-blossomed Jewelweed, which blooms a bit earlier. (The crushed stems of both species yield a clear juice that sooths the burn from Poison Ivy.)

Himalayan Balsam’s hollow but sturdy stalks are beautiful in their own right, though they are usually hidden deep in the understory. A tenacious competitor, it can quickly take over an area and produce a thick stand that leaves no room for other plants. Those who have had the experience of struggling to control a well-established stand realize this plant’s magnificence comes at great expense.

Jewelweed One

Its pink flowers are succeeded by an equally elaborate exploding seed pod that can distribute hundreds of seeds several metres in every direction. If you see a few of these flowers you might want to enjoy their beauty now – and then pull up the plants before they can seed next summer’s forest.

Jewelweed Sundown

 

Top photo: Monarchs’ Realm

 

house of orange

PHOTO POST

The star that burns most brightly in our garden recently is the Butterfly Weed (aka Pleurisy Root, Butterfly Milkweed). This not-so-common member of the milkweed family is said to attract Monarch butterflies.

Panorama in Orange (click images for larger view)

So far this year the Monarchs haven’t paid much attention, but other insects have certainly noticed these blooms. The Musca domestica (housefly) looks its resplendent best against a backdrop of Butterfly weed.

Transparency

Even where the flowers have little colour, it’s not hard to spot some flashes of orange. This dragonfly has flown across the road from the marsh to check out the arugula flowers, while bronze and brassy damselflies also flit around the garden.

Transparency II

 

Sunshadow

Intense summer sun plus a small but very welcome shower sped this sunflower toward maturity. Just two days separates these photos, as yellow-green quickly turns to orange.

Count To Three

The dry heat of recent weeks had many things switching to the hues of fall. With lawns drying up and many flowers withered, some days it looked more like September than July. The burnt ochre of the garden ornaments below – fragmented memories of someone else’s long-ago Mexican vacation – fit right in.

Repose

Some flowers, of course, still ring out in defiantly different tones.

Coiled Blue

Borage (above) and white water lily (below) look cool even when the sun is directly overhead in a cloudless sky.

Deep Light

Yet the palette in our corner of the world is trending toward yellow, gold, and orange, as rudbeckia, sylphium, and a flaming lily, below, come into their glory.

Orange Flows

Top photo: Buzz buzz (click here for larger view)

heat of summer

PHOTO POST

As the most intense heat wave in years takes hold of the lakeshore, the growth of some plants accelerates, others parch and wither, and many marsh-dwellers seek mid-day shade or the cool of twilight hours.

With a still bountiful supply of moisture, green plants in the marsh are tall and lush, though the air is steamy with transpiration.

Featured Creature (click images for larger views)

Water levels are dropping, exposing little isthmuses and giving grasses a chance to spring up out of the mud. This killdeer is feeding by sunset in Westside Marsh.

Stepping to the Sunset

Garden plants are remaining lush only if they are watered every day or two – but these Evening Primrose blossoms did grab onto a generous morning dew.

Primrose by Morning

 

Blooming Bergamot

Bergamot, above, and Viper’s Bugloss, below, answer the mid-day sun with particularly intense bursts of colour.

By a Thread

 

Ring Bill

Ring-billed Gulls, above, and Osprey, below, keep watch over waters of marsh and lake, and swoop down frequently to grab small fish.

Balance One

 

Balance Two

 

At Roost

The chilly waters of Lake Ontario can usually be counted on to keep the air a bit cooler – though on a calm night the cooling effect seems not to make it even 50 meters inland. Perhaps that is why two Great Blue Herons forsook their fishing grounds in the marsh one night and joined the gulls out on the Port Darlington breakwater.

 

Heron at Light House Rock


 

Top photo: Red Goose (click here for larger view)

Colour in the eye of the beholder

Photo Post

The marshes are a sea of green, wild and garden flowers are coming into bloom, and one 24-hour period this week saw a burst of nesting activity by the Snapping Turtles.

Notwithstanding all the vivid hues, the tranquility of many midsummer days comes across beautifully in photos of minimal colour.

Waterbug (click images for larger view)

 

Spin

In our garden the Asiatic Lilly (above) and Sea Holly (below) were just about to bloom.

Sea Holly

The lawn is dotted with Daisy Fleabane (below).

Pink & Yellow

Even in the compost bin, an occasional “flower” sprouts from the dark decomposition.

Compost Flower

 

Beach Path

On the dunes and on the marsh, elegant forms rise from the sand and water surfaces.

Making Waves

 

Sunset Stride

As the sun dips below the horizon, a family of swans climbs out on a mud flat, while a turtle digs a lakeside nest to deposit her eggs.

Excavator

 
Top photo: Close Look (click here for larger view)

 

light lines

PHOTO POST

Bright light and shadows run through this week’s post, with photos from garden and forest, marsh and lakeshore.

When there’s a fork in the road, take it (click images for larger views)

 

Mullein

This Mullein plant, lit from the other side by early morning sunlight, grows just beneath a bird feeder. The spot is a favourite hangout for squirrels, who encourage the Blue Jays to spill as much seed as possible.

Feeding Grounds

Purple Finches (who always look more red than purple to me) also visit the same feeder.

I See Red

 

Goldfinch

The Goldfinches and Hummingbirds get their own special feeders.

Wing

 

Antennae

The above photo comes from a bit farther afield, on the bank of a small pond within the grounds of the Darlington Nuclear Station.

Below, the shadows of sunset play across the surface of Soper Creek where a submerged branch breaks the gentle current.

Ripple

On the same evening, a Kingbird rests above a logjam on Bowmanville Creek.

Kingbird

Dozens of Dunlins swirled along the lakeshore on a breezy afternoon, plucking insects as waves splashed over the stones.

Landing

 

Seven

 

Fast Runner

Every so often the birds would rise together in an instant, swoop out over the water in a fast-moving cloud, and circle back to a new spot a bit further down the shore. What caused these sudden flurries? The Dunlins, it appeared, didn’t appreciate the company of a Grackle, whose stroll along the beach repeatedly got too close for comfort.

Grackle

The edge of summer

 PHOTO POST

While a few migratory birds are still stopping by on their way to nesting grounds far to the north, some resident birds have already hatched big broods. Meanwhile woodland flowers are hurrying to develop before the leafy canopies above cast a blanket of shade.

A few days ago a pair of Dunlins paid a colourful visit to Port Darlington beach, pecking at the wet sand in search of tiny insects. Since they nest along the Arctic coast and the shore of Hudson’s Bay these birds still have a long way to fly.

Travellers (click images for larger views)

Along Bowmanville Creek just north of the harbour, a ramshackle beaver lodge has appeared vacant since it was submerged by last spring’s high water. But this curious Mink seems to be quite at home.

Guardian

 

Preaching to the Choir

Two weeks ago there was little trace of these ferns beyond the stumps of last year’s growth. Now they have emerged and unfurled their fronds more than half a meter high. In the interim the muddy forest floor was dotted with fiddleheads.

Fiddlehead Duet

Another woodland plant is just about to present a well-kept secret. The intoxicating aroma of the Mayapple blossom will soon be present –  but you have to get down on hands and knees and peer under the umbrella-leaves of the Mayapple to find its single flower. The single delicious yellow fruit, similarly hidden, will ripen in August – and the squirrels will be ready.

Promise of a Flower

Under a tree on a sand dune, Vinca is now in flower.

Ground Cover

 

Rafting

In the marsh, shoots of green are just emerging amongst the sun-bleached stubble of last year’s reeds. A pair of Common Terns found that a couple pieces of the pithy cattail stalks make a fine raft.

The Great Blue Herons keep watch around the marsh’s edge for the many fish that ripple the water’s surface.

Focus

 

Sunday Morning

Pairs of Canada Geese are watching their nests throughout the marsh and along the creek banks – but some families have really gotten a jump on the season.

Slipstream

Top photo: Beachcombing (click here for full-size image)

Don’t blink, you’ll miss it

PHOTO POST

Spring is a long time coming this year, especially along the lakeshore – so we can expect it may give way to summer in a great rush.

In the marsh the vegetation looks brown and dry – but a muskrat can still find a fresh green salad, simply by uprooting a cattail.

Underneath the trees in the garden there isn’t a lot of colour either, though last year’s hydrangea leaves still cut a sharp figure against the dark damp soil.

Leaf Litter

Just a few inches away, however, things are changing fast. Like rhubarb, the Mayapple is one of those plants that emerge from the ground with leaves already fully formed.

Mayapple One

Within a few days, these new shoots have spread their umbrellas.

Mayapple Two

 

Scilla siberica

The Scilla is next to flash some dazzling colour, followed within a few days by Lungwort.

 

Lungwort

Robin in late afternoon

Robins have been hanging around waiting for spring for a full month. Likewise, the Red-wing blackbirds have endured weeks of freezing temperatures, not to mention an ice storm in mid-April.

Redwing One

 


Redwing Two

It’s a long time to put up with unseasonable cold, just to be first in line for prime nesting sites. Fortunately for these birds, the clouds of midges that often darken our skies can provide a change in diet after weeks of scrounging last year’s leftover seeds.

 

Scissormouth

 

Top photo: Eats roots and leaves (full-size version here)

Acoustic conditions, conservation planning, and the St. Marys mine

How much external noise can you add to a wetland environment before the wildlife inhabitants really start to suffer?

Relatively little scientific research appears to have been conducted on this subject. Yet an understanding of cumulative noise pollution is essential to properly assessing the long-term impact of the proposed St. Marys Cement under-the-lake mine south of Bowmanville.

A recently published research paper found biochemical markers of increased stress levels, as well as reduced hatching success, among birds chronically exposed to industrial noise. We’ll get to that paper below, but first, here’s a refresher on the setting for the mine proposal.

The St. Marys mine proposal (official Project Description here) describes a mine-entrance tunnel near the bottom of the existing limestone quarry on the Lake Ontario shoreline. The tunnel will lead to under-the-lake caverns, which will be excavated over a 100-year period.

The project site is adjacent to two Provincially Significant Wetlands, Westside Marsh and Bowmanville Marsh. These wetlands are among the remnants of what was once a very extensive array of coastal wetlands all around Lake Ontario. The remaining coastal wetlands are still of key importance to resident and migratory bird populations and to many freshwater fish species who depend on the wetlands at some stage of their life-cycles.

If the project is approved as proposed, 4 million tonnes of limestone will be blasted and hauled out from these caverns each year. The operation will require ventilation fans moving fresh air into the mine and exhaust air back out, to enable work to be conducted throughout a network of chambers that will eventually extend approximately 14 square kilometers under the lake.

Mining trucks will carry the limestone out of the mine and into the quarry, where it will be crushed into aggregate suitable for construction use. Then approximately 500 truckloads per day (based on seven days/week haulage) will leave the St. Marys site carrying aggregate to the primary market on the east side of the Greater Toronto Area.

The environmental viability of the project must be assessed by looking at the cumulative effects. The blasting, drilling, ventilation fans, trucks and crushers will add noise to an environment that is already anything but quiet.

At present both Westside Marsh and Bowmanville Marsh are subject to significant anthropogenic noise levels on a 24-hour basis. The operations of St. Marys are just one component of that noise.

Noise from St. Marys existing operations comes from blasting and hauling limestone immediately to the west of Westside Marsh, trucking of cement products, and major excavation and berm-building directly north of Westside Marsh.

Another constant noise source is Highway 401, just to the north. At present the traffic noise consists of a constant loud hum, punctuated by accelerating trucks, motorcycles, and sirens. The St. Marys mine would add to that traffic noise, as 500 or more additional trucks come and go every day. (The route in and out of the St. Marys property, and on and off the 401, are shown in yellow on the above map.)

One of the busiest rail lines in Canada passes directly north of the quarry, about 500 meters north of Westside Marsh, and through the north end of Bowmanville Marsh.

Above, an eastbound CN freight train skirts the St. Marys quarry and cement plant. Below, a CN freight train on the bridge over Soper Creek at the north end of Bowmanville Marsh.

 

Noise and stress in bird populations

A recent paper published in the Proceedings of the National Academy of Sciences (US) notes that noise pollution “alters habitats, degrades natural acoustic conditions, and partially or fully excludes species that are sensitive to noise exposure from affected areas.”1

Among the species that remain in noise-affected environments, the effects on survival and fitness are complex. One way to study this is to correlate measured noise levels with measured levels of baseline circulating stress hormones (glucocorticoids) in birds. The paper notes,

To date, no studies have simultaneously examined relationships among noise, GCs [glucocorticoids], and fitness in animals that settle and breed in natural areas exposed to chronic anthropogenic noise.

The paper looked at three species of cavity-nesting birds with different noise tolerances, in a New Mexico wildland which is now interrupted by an array of natural gas compressors. The evidence “strongly suggests that chronic anthropogenic noise induces stress and hypocorticism in birds.” Furthermore, with one of the studied species, the western bluebird, increased noise was correlated with a lower rate of hatching success.

There are a number of explanations for the stress response.

At lower exposure levels, anthropogenic noise is more likely to elicit stress responses indirectly by increasing the difficulty of coping with external challenges (e.g., territory defense) or by creating anxiety through reduced detectability and predictability of threats (e.g., acoustic masking of predator alarm sounds), or both.

Given the capacity for chronic noise to consistently mask biologically relevant cues, animals living in areas with high levels of noise may fail to receive information about their local habitats, leading to a continual state of perceived unpredictability and reduced security.

Citing a range of other studies, the authors further explain how chronic noise pollution disrupts the normal sensory perceptions of wildlife.

The distance over which birdsong and other sounds are effectively transmitted, their ‘active space’, is significantly reduced by increases in ambient background noise. Anthropogenic noise, acting as an acoustic blanket, can reduce or inhibit detection of hetero- and conspecific vocalizations that birds and other animals use to gain information about predation threats. For example, the presence of birdsong and chatter is thought to signal the absence of nearby predators.

How does noise pollution affect the wildlife in Westside and Bowmanville Marshes? Are there species which would otherwise make these wetlands home, if it weren’t for chronic noise levels? With increasing noise levels, will some of the existing species be driven out, or will the populations be weakened due to lower reproduction rates? These are complex questions – but they must be answered before the impacts of additional noise, due to a major mining/extraction project, can be properly assessed.

In spite of huge environmental challenges these wetlands remain home to a wide variety of species. Within this small area there are cattail marshes, open water, wetland forest, upland forest, and even a small fen. Among the many species that live here are various waterfowl, fish, wading birds, osprey, kingfisher, beaver, muskrat, and predators including otter, weasel, marten, raccoon, coyote and fox. These wetlands are also vital staging areas for the many migratory birds which fly over Lake Ontario in the spring and fall.

Raccoon on the bank of Westside Creek at the north end of a beaver pond; ospreys which nest each year on platforms in Westside Marsh; juvenile Black-Crown Night Heron photographed in Bowmanville Marsh.

These wetlands are officially designated as “Provincially Significant Marshes”. The review process for the St. Marys under-the-lake mine must make us ask, how much significance does the province actually afford to this environment?

The authors of the paper on noise pollution and avian stress levels note,

In this era of unprecedented, large-scale human-driven environmental change, preservation or recovery of natural acoustic conditions should be a key aspect of conservation planning and is a critical step toward successful conservation of protected species.

Given the importance of natural acoustic conditions to conservation planning, should the province of Ontario give the OK to increased noise pollution from St. Marys Cement?

 


1“Chronic anthropogenic noise disrupts glucocorticoid signaling and has multiple effects on fitness in an avian community”, Proceedings of National Academy of Sciences, 14 November 2017

leaf to leaf

While fall colours quietly creep into woods and wetlands, one group of leaves remains vibrant green: the lily pads. In Bowmanville Marsh and Westside Marsh you may spot a sandpiper treading lightly from leaf to leaf while feeding on aquatic insects, or a beaver swimming from one lily patch to another while happily munching on a flower.

The herons, too, keep watch over lily pads for signs of movement from fish or frogs. Here a young black-crowned night heron hopes for a meal, at the edge of a dense stand of cattails which have lost nearly all their summer colour.

Toehold (click images for larger view)

The fall palette is reflected in the water as a beaver makes a swift passage across the marsh by setting sunlight.

 

Straight Ahead

The resident mute swans are often seen feeding among lily pads – and they leave their mark even when the birds themselves are nowhere in sight.

Feather Two

 

Feather One

 

Sandpipers prove that there are great advantages in being light of weight but wide of foot. On a quiet end-of-summer evening the surface of the marsh teems with insects, and the lily pads make even the deeper waters accessible to this wading bird.

Fast Forward

 

Afloat

In the vegetable garden, meanwhile, another nimble footed creature is springing from leaf to leaf – a grasshopper feasting on collard greens.

Copper Tack

Top photo: Sandpiper Buffet (click here for larger view)