Of the birds that breed in Canada, 90% migrate. Shorebirds are the most accomplished travellers. For most migrating birds, the journey takes three to four weeks. But how do birds find their way on migration routes? Some follow geographic features, like mountains and lakes. Day flyers are able to relate to the moving position of the earth relative to the sun. Flying in daylight means exposure to predators and risk of dehydration. Night flyers don’t have those problems, but as they navigate by the stars they sometimes get off the course on cloudy nights. Others make use of the earth’s magnetic fields. And some learn the routes from their parents when they travel in family groups, as geese do, for instance. Those that are abandoned by their parents in early life, like cuckoos, find their way unaided by inborn generic route-finding skills, like the Monarch butterflies.

Of course, birds are not the only migrants. Most animals are born to move. They are powered by different needs but all of them revolve around the availability of food and water. Many mammals, insects, fish and reptiles also perform miraculous feats to survive: Monarch butterflies, caribou, elephants, wildebeest, whales, salmon and turtles to name a few.

The drama of migration plays out across the world. Millions of animals are on the move in the Serengeti, often fraught with danger, such as crocodiles at river crossings. Some don`t make it, but the mass movement is guided by a collective intelligence – and the need for sustenance. Africa’s parched Serengeti is the arena of bitter rivalries between cheetahs, lions and hyenas during the dry season when all of them fight for survival. But when the rains come, the plains flush green again and attract millions of gazelle, zebra and wildebeest.

For the White-bearded Wildebeest migration is a way of life. They are the most numerous antelope in East Africa and they travel through some of the most exciting landscapes in the world, from the lofty heights of the Masai Mara plains in Kenya to Serengeti in Tanzania, covering an area of almost 80,000 km² over the course of a year in constant search for fresh grazing.

Crabs migrate across Christmas Island, despite hordes of army ants and trigger fish in the Indian Ocean. Perhaps it’s because of these dangers that males go first and females follow.

Delicate Monarch butterflies inspire awe with their phenomenal migration. As one of the planet’s most astounding navigators they travel up to 4,800 km, flying for some 900 hours, to reach overwintering and breeding sites in central Mexico. Once there, they face new perils: logging and cold snaps. A new generation, hatched there, then heads to a place it has never seen – and finds with unexplainable accuracy a milkweed patch in the Rouge Valley, among other places.

In the still waters of the Sargasso Sea in the Atlantic Ocean, eels embark on a journey of many thousands of kilometres while being exposed to attacks from various marine predators. Once the mature eels have spawned in the Sargasso, they die, and their offspring then start the marathon journey back to “home” — wherever that might be.

Whales migrate along the west coast of North America for many hundreds of kilometres. They are among the largest predators on earth and migrate by sonar. The females travel in family groups. Some make the trip 50 times in their lives.

Among the migrating sea turtles, the largest of them – Leatherback turtles – rarely come ashore here in Canada, but thousands of them gather in Canadian waters each summer.

Their shell can measure up to 2 m and they weigh up to 900 kg. They grow to this size by feeding almost exclusively on jellyfish, which they find in the oceans. They swim at speeds of more than 9 km/h and have been recorded at depths of 1,270 m. They migrate across entire ocean basins and survive in water that is much too cold for other marine turtles.

Like all sea turtles, the Leatherback has both front and rear flippers, but it is the only sea turtle whose flippers have no claws. In Canada they are found off the coasts of British Columbia, New Brunswick, Nova Scotia, PEI, Newfoundland and Labrador. They are powerful swimmers, making the trip from Nova Scotia to Trinidad in four months.

Unfortunately, the Leatherback population has declined more than 60% since 1982 and they are now on the critically endangered species list. That is why their nesting places are so fiercely protected. When I visited one of their nesting grounds on the Playa Grande in Costa Rica’s Parque Nacional Marino las Baulas – a reserve especially created to protect the egg-laying places of Leatherback turtles – I found strictly enforced regulations in place. Mating takes place at sea, and between October and February female Leatherbacks go on land to lay their eggs and then immediately return to the sea. When the nestlings hatch, they scramble to the sea and the males never return to land during their entire life.

Other than in Costa Rica, Leatherbacks also nest on beaches in Trinidad, French Guiana, Surinam, St. Croix, Mexico, Irian Jaya, Papua New Guinea, and Gabon. Although scientists have a sense of where Leatherbacks are found in the world, they are still only in the early stages of understanding what migration routes Leatherbacks take to get from the tropical waters near their nesting beaches to the waters where they forage for food or search for ocean shores in the northern parts of the planet after the egg-laying season.

But let’s get back to our feathered friends. Birds are truly the most spectacular migrants of them all, and one wonders how they do it. There is at least one scientific explanation:

What helps birds to make those long and arduous migration flights is the way they breathe. In mammals, only about 20% of the oxygen in a breath of air is absorbed by their lungs. A bird’s breathing is much more efficient. When it inhales, the air passes first into its lungs, which are relatively small and lie beneath the bird’s spine, moulded against the ribs. The air then continues through a number of little tubes into small air sacs that lie towards the rear of the body. When the bird breathes out, the air in the rear sacs moves back along another set of tubes to a different part of the lungs. With the next breath, this inhaled air moves on yet again, out of the lungs and into another group of air sacs located towards the front of the body. Then, with the next exhalation, that air leaves the bird’s body through its nostrils and goes back into the atmosphere. In this way, the air-flow in all of the many passage ways and air sacs of the bird’s respiratory system is always in the same direction and the absorption of oxygen from each intake of breath is almost total. All flying birds share this feature.

Another thing that makes migration flights possible is the great versatility of a bird’s wings. Thanks to the manner in which the feathers slide over one another, the surface of the wings remains perfectly smooth, regardless of whether the wings are closed, or opened, or at any position in between. The feathers are also crucial in minimizing turbulence.

Beating wings demands a lot of energy. So to conserve energy, birds have to do their wing-beating in flight as economically as possible. One simple method of achieving that is to stop beating wings every now and then. Another is to regularly interrupt rapid wing beats. Wood- peckers, for instance, do that by holding their wings closed tightly against their body once in a while when flying. Their forward movement is such that, without the drag created by open wings, they continue to shoot forward through the air. However, they cannot do this for long. Deprived of the lift created by the wing beats, they quickly lose height and after a few seconds have to resume flapping.

Only small birds can use this energy-saving trick. Bigger and heavier birds have developed other ways to economize on their wing beats. They stop flapping with their wings not closed but open. The surface area of their wings is big enough to enable them to glide. Raptors and pelicans do this regularly. How long they can glide depends on how high above the ground or water they are, how much height they can afford to lose, and how fast they are travelling.

Slogging through marshland in rubber boots and rain gear, or facing a chilly on-shore wind standing at the edge of a lake in the dawn hours of a gray, foggy day in early April, holding on to your hat with one hand and to a pair of binoculars with the other, is the hard price you pay for witnessing one of nature’s great miracles, the semi-annual migration of birds. But it is worth every bit of effort and discomfort. To see those avians fly between their wintering grounds and their nesting sites – often for thousands of kilometres – is an exhilarating experience you are not likely to ever forget.

We first see the changing of the guard as winter visitors vanish from our feeders and head back north. We then get the jump on Spring with the first ducks, swans and geese arriving from the south. Shorebirds are among the later arrivals and flybys of Whimbrels can be seen in May. In Toronto we are lucky to live in the best area for watching bird migration as one of the major flight corridors is right overhead. In the Spring, huge numbers of birds migrate to the boreal forest in our north to breed. The boreal forest supports more than 50% of the global population of bird species. Of all the waterfowl of North America, 38% breed there, along with seven million shorebirds. Like many of the 29 shorebird species found in Ontario, of which 22 breed regularly in the province, Whimbrels, those marathon migrators, are among nature’s most impressive wayfarers. Those that pass through here breed in the northern wetlands and tundra around James Bay and Hudson Bay and winter more than half a world away in Brazil. In 2008, one banded Whimbrel was tracked covering 5,057 km in 143 hours at an average flight speed of more than 35 km/h.

Watching huge flocks of shorebirds, warblers and raptors passing overhead is an edifying experience. It teaches us lessons about determination, stamina, strength, endurance and accomplishments – lessons that we can apply to our own lives.

There are several good birdwatching sites in the Toronto area. Among them: the Rouge Park, Colonel Samuel Smith Park, Rosetta McClain Gardens, the Leslie Spit, Humber Bay Park, Thickson Woods, and the Cranberry Marsh.

For more information on bird migration check www.migrationresearch.org with links to the Frontenac Arch studies and to the McGill Bird Observatory in Montreal for bird banding statistics. Additional information is also available from Bird Studies Canada: www.birdscanada.org

In his book The Life of Birds, David Attenborough says: “We humans are now the most widespread competitors that birds ever had to face. We are also by far the most powerful. We have already exterminated whole species of them by direct attacks, but the greatest destruction we have wrought has been inadvertent – a consequence of the wholesale changes we have made to the face of the planet. That damage need not continue. We now have the knowledge and skill to maintain all the wonderfully rich range of birds that still exists on earth in all its complexity and glory. All we need is the will to do so.”

Quick quiz: how many migratory bird species stop over in Canada en route to wintering and breeding grounds? The astonishing answer is: more than 500.

Note a few important dates this Spring: National Wildlife Week, April 8-14; Earth Day, April 22;

Migratory Bird Day, May 12; and International Biodiversity Day, May 22.

Make the most of the migration season in Spring and Fall and enjoy the outdoors. S.G.

Sources: Canadian Wildlife Federation, Nature Canada, Ontario Nature, Bird Studies Canada, Canadian Wildlife Service/Environment Canada, U.S. Fish and Wildlife Service,  Leatherback Turtle Workshop Group, The Life of Birds (David Attenborough), Facts and Fallacies (Reader’s Digest), Nature’s Great Events (BBC), The Green Book (Steve Gahbauer) and personal travel and field notes.

This involves the concept and knowledge of cell behaviour, such as cell division, mitosis (the process by which a nucleus forms two exact copies of itself) and the two most important things that cells do: photosynthesis and respiration. Only some kinds of cells carry out photosynthesis, but all kinds of cells respire, i.e. they inhale and exhale air.

Photosynthesis makes food for life processes and respiration gives energy to them. Photosynthesis requires chlorophyll, light, carbon dioxide and water to make glucose and oxygen. Respiration does the reverse: it uses up glucose and oxygen and produces carbon dioxide and water. Photosynthesis changes light energy into chemical energy and respiration changes chemical energy in glucose molecules into energy needed for life processes.

Thus, science explains the food chain, how habitats and ecosystems are formed, the ecology involved, and how air and water, plants and wildlife create the environment. But we need to understand how it works – grasp the fact that everything in nature is interrelated and that all living things interact and rely on each other. No living organism lives completely on its own. It depends on other organisms and they depend on it. That’s what ecology is all about – it is the study of the relationship among organisms and between life forms and their environments.

Organisms interact on four levels: individuals make up a population, populations make up a community, communities make up a biom, and bioms make up the biosphere. Any community of living things interacting with its environment is an ecosystem. And the important thing to remember is that since all parts of an ecosystem are interrelated, each part is affected by all the other parts. Therefore, if one part is changed in any way, all the other parts will be changed too, and equilibrium – the balance between opposing physical forces – is lost. That’s why human interference, in a misguided attempt to “manage nature,” has often such a negative impact on the environment.

To appreciate ecosystems we need to understand their two major components: habitat and niches. The habitat of an organism is the place in which it lives. Think of it as the “address” of the organism. The niche of an organism is its total role in the natural community. Think of it as its “job” or “occupation.”

Organisms in an ecosystem may be linked in feeding relationships, called food chains. Clover is food for the groundhog, the groundhog in turn is food for the fox, and a larger predator eats the fox. This is known as the food web: who eats who defines an ecosystem. Some food chains are quite long, but many are just simple, let’s say wheat > mouse > owl.

Then there are the feeding relationships in which organisms help provide food for other organisms without being eaten or killed themselves. These are parasitisms, mutualisms and commensalisms. Parasitism is a relationship between two organisms in which one benefits and the other is harmed (parasite and host). Mutualism is a relationship between two organisms in which both organisms benefit (lichen and fungus). Commensalism is a relationship in which one organism benefits and the other neither benefits nor suffers (“Old Man’s Beard” lichen and spruce trees).

Nature is full of examples that can teach us about the mysteries of life. Take a chicken egg, for example. From shape to content, every feature of it is an example of perfection. The egg’s shape is its strength. Its five principal parts provide the entire life support system for the developing bird. The egg shell is porous, allowing moisture to evaporate and oxygen to replace it. The shell membrane on the inside of the egg consists of two layers close to each other, except at the larger end of the egg where they separate to create an air pocket, which does not yet exist when the egg is laid. The egg white contains many crucial proteins, stores water and offers insulation from sudden changes in the outside temperature. The yolk is a mixture of suspended proteins, fats and carbohydrates. The germ – the most important part – is a pinhead-sized blob on top of the yolk that developes into a new chick. No single part of the egg is superfluous, everything exists to protect and nourish the developing life within.

Metamorphosis is another of nature’s marvels. The change from a tadpole to a frog, or a caterpillar to a butterfly, not only requires that old limbs be discarded while new appendages sprout, but it also means that most of the creature’s internal organs and nervous systems disappear, to be replaced by new equipment for moving, breathing and digesting food. Metamorphosis is a stunning feat of genetic engineering. Butterflies begin life as an egg that hatches into a caterpillar, which spins a silk cocoon (chrysalis) in which it begins its transformation to a winged insect.

And we can learn a lot from plants when it comes to seed propagation. Millions of years before humans invented the wheel, plants were already utilizing most of the methods we later devised for getting around. The catch is, of course, that plants themselves don’t move from place to place – their seeds do. They accomplish this by rolling like wheels (tumbleweed), riding on wind (milkweed, dandelions) or water, (mangroves, coconuts), or being carried overland on the backs of animals (burdock) or the feet of birds. And so the cycle continues.

Think about some of these interactions, and our relationship and connectedness to the natural world around us, during your next hike in the Rouge Valley, where many of these wondrous things can be observed. S.G.

Sources: Planet Earth (Time), Canadian Wildlife Federation, Facts and Fallacies (Reader’s Digest), Discovering Biological Science (W.A.Andrews et al.), and personal field notes.

One of the most prolific – and least observed – life forms are fungi, defined as any of a group of spore-producing organisms feeding on organic matter. Fungi include moulds, yeasts, mushrooms and toadstools, and lichens. We like to think of ourselves as the dominant life form on the planet, but fungi may be gaining on us, even now that we have passed the seven billion mark. Tightly woven into our daily lives, they are in the beer and wine we drink and in the bread and cheese we eat. They are in the drugs we take, they are in the fuel and in the preservatives we manufacture. Thousands of species of plants and animals depend on fungi in ways that scientists are only beginning to understand. What we do know is that fungi display stunning chemical properties. Some can ingest granite, tar or uranium and either transform them back into basic elements or lock them into stable, harmless forms.

Scientists, who have identified hundreds of thousands of fungi species and believe there are a million more yet to be named, have found from DNA analysis that fungi have genetically more in common with animals than with plants. They surround us (and sometimes inhabit us) almost always unseen. Estimated to constitute one quarter of the total biomass of dense forests, microscopic fungal spores coat every surface of the ecosystem.

Neither plants nor animals, fungi form their own separate kingdom of life that is mostly unseen, but all pervasive. A thimbleful of soil can have two kilometres of microscopic fungal strands running through it. Fungal networks are like veins and capillaries in the soil, keeping ecosystems alive. The number of spores in one gram of soil can be up to three million; the number of spores in a single mushroom can be billions. And spores can remain dormant for up to 20 years. Mushrooms and tree-clinging polypores are only the external, spore-producing fruiting bodies of fungal organisms. Underground fungal fibres comprise an estimated 90% of the subterranean biomass in forests. I have heard it said that this biomass weighs more than the trees above ground. It is plausible when you think that fungal threads weave through every nook and cranny of the upper soil of most habitats, intertwining with tree roots and entering rotting logs, dead animals and droppings, forming an immense living web.

And then there are the lichens, composed of fungi and algae in symbiotic union. So common are they that they are often overlooked. But lichens are one of the most remarkable life forms on earth. They are not plants, like the mosses with which they are commonly confused, but a unique combination of two distinct organisms – green algae and lichen-producing fungi. Neither would thrive, or even survive, without the other. Lichens have no roots to absorb water and nutrients from the soil, and no protective outer coating such as the cuticle of leaves. So the fungal partner develops a thick outer cortex that protects the algal layer underneath. Moisture can readily pass through it and atmospheric particulate matter can easily penetrate to the inner fungal layer. Together they combine to form tens of thousands of lichen species of incredible diversity in appearance and habitat. Lacking chlorophyll, fungi cannot make their own food and photosynthesis does not work underground. But the algae produce carbohydrates for the fungi and, in return, the fungi provide a protected place to live. In working together, algae and fungi create a tiny self-sustaining ecosysten in which the fungus is the dominant partner and architect of the symbiotic relationship. As calamitous as this arrangement may seem, the partnership has created some 14,000 species of lichens worldwide, with a big diversity in size, shape and colour. It is one of nature’s success stories.

The sensitivity of lichens to the degradation of air quality was recognized as far back as the 19^th century and for the last 100 years it has been used to monitor atmospheric pollution. The degree of sensitivity, however, varies among species. Some have zero tolerance for pollutants and die in their presence; others tolerate some pollutants but become stunted in growth. In heavily polluted urban areas lichens may disappear altogether. A lichen survey at the Todmorden Mills Flower Preserve in the Don Valley five years ago has clearly shown the effect urban air pollution has on these fragile life forms.

Boreal Felt Lichen are native to Canada and grow on branches or trunks of Black or White Spruce, Balsam Fir, and occasionally on Red Maples, in mature forests on cool, damp, exposed slopes. Those of you who have been camping in provincial and national parks have surely come across lichen communities. We even have some on rocks in the Rouge Park.

So do we love fungi? Maybe not enough. We love birds, deer, turtles, trees and flowers, but perhaps spiders and snakes not so much. Yet we should care about all forms of life. They are part of who we are.

On another note, now that the splendour of coloured leaves is over, the question arises again: does the colour of autumn leaves act as a warning signal to insects that use trees as hosts for the winter? The answer is maybe. As chlorophyll breaks down in leaves, the amount of green pigment is reduced, allowing other hitherto “covered” pigments to become visible. So we know how leaves change colour, but controversy still surrounds the why.

Scientists have two leading theories. One, known as co-evolution, argues that leaves turn red to indicate their plant could have higher levels of toxins that would be harmful to insects that look for winter homes, food sources, or places to lay eggs. This is similar to bright red colours on animals that warn “we are poisonous.” The second theory is that anthocyanins, which are responsible for pink, red and purple colours, act as sunscreens to prevent damage to leaves from excess light in the Fall. Both theories are just that, theories, and scientists are still debating the question.

Nature is full of mysteries and a never-ending source of wondrous discoveries. As Frank Lloyd Wright says, “Study nature, love nature, stay close to nature. It will never fail you.”

Have a safe and happy holiday season. The next Nature Notes will be in the new year. S.G.

Raptors seize and devour living prey (except for vultures that dine on carrion) and are well equipped for their predator role. Apart from amazing aerial skills, three things make raptors expert and efficient hunters: keen eyesight to locate prey, powerful talons to grasp and kill, and a sharp hooked beak to rip apart their meal. Hawks and eagles are in the family of accipitridae – diurnal birds of prey with hooked beaks and hooked talons. Accipiters (true hawks) have small heads, short rounded wings and long tails. Buteos (buzzard hawks) have a stocky build and a wide tail. They include Red-tailed Hawks, Swainson’s Hawks, Rough-legged Hawks, Red-shouldered Hawks, Broad-winged Hawks, Short-tailed Hawks and Northern Harriers, also known as Marsh Hawks – and all of them can be seen above the Rouge Park at one time or another. If you are lucky you may also spot a Goshawk or a Common Nighthawk. The latter leaves its daytime hiding places on the ground late in the day and rises to truly prodigious heights in the darkening sky. It is hunting for flying insects, admittedly small food for such a big bird, but insects make up in quantity what they lack in size, The Goshawk is a large, powerful, bold and strong bird, one of the accipiters that hunt by direct attack rather than by the watchful waiting-for-prey that is common to most large hawks. After my son and I had participated in creating a special Goshawk habitat several years ago, I was happy to see this magnificent raptor nesting at its new habitat near the Rouge River. I also observed some at bird counts in the park.

Occasionally one sees a Bald Eagle soaring over the Rouge Park. The Natives say it is a good omen. The Bald Eagle is the largest of Canada’s raptors and obviously it is not bald. Its name comes from the old English word balde which means white. Males and females both have a distinctive large white head and a dark-brown body. Young birds have brown heads and may not develop adult colouring for five years. Bald Eagles and Golden Eagles are the only two of 59 eagle species world-wide that call Canada home.

It only makes sense that such a large raptor would build the biggest nest. With a width of more than two metres, matching their wingspan, and a depth of four to six metres, eagle nests are really whoppers. You can find them on the top of the tallest trees – pines, Red Oaks or Black Maples – near bodies of water. In Ontario, the Endangered Species Act protects Bald Eagles and their nests.

Northern Harriers, about the size of a crow, are the only harrier species found in North America. They have long tails and a wingspan of about one metre. Males are smoky-gray with a white belly. Females and immature birds are brown with buff-coloured underparts. Both sexes have a white patch on the base of the tail. We have a few Northern Harriers in the Rouge. They are usually seen around the Beare Hill landfill site and over the wetlands. They hold their narrow wings in a shallow V-shape as they glide over open fields and marshes, flying low so they are easy to spot and identify.

Vultures are scavengers – nature’s clean-up crews – that can often be seen soaring high up in wide circles. The blackish, eagle-like birds have naked heads, which makes them less beautiful but easy to distinguish from other birds of prey. They belong to the family of cathartidae. Falcons have their own subfamily (falconinae) and Ospreys are in the pandionidae family, while owls are strigidae, except Barn Owls, which are tytonidae. Falcons have long, pointed wings and long tails. The falcon family includes kestrels, robin-size swift-flying Merlins, Gyrfalcons and Peregrine Falcons. The Ospreys are fish eaters and their eggs used to be highly favoured by egg collectors in the 19th century. It’s not surprising, because Osprey eggs have a pale pinkish cinnamon ground colour, heavily endowed with rich chestnut-coloured spots – irresistible to diehard oologists.

Then there are those loveable darlings, the owls. In the Rouge Park we often see and/or hear Short-eared and Long-eared Owls, and occasionally some Hawk Owls around the wetlands. Once I had a long, silent conversation with a Great Horned Owl at a bend in the river where we often have lunch with school groups. I had flushed it out as I rounded a curve in the trail and it then sat for a long time on the branch of a coniferous tree, watching me while I looked back and admired the bird’s beautiful plumage. I had a camera along but it never occurred to me to use it. Finally, I quietly walked away before my presence would cause a stress for the bird.

In 2004/05 we had an irruption from Great Grays when the dearth of suitable food at their normal habitat caused them to look elsewhere. Compounding the dilemma was the fact that for that period there were no nests because Great Grays use abandoned Goshawk nests. But Goshawks left the Assiniboine Forest (where Great Grays normally live) due to human activties (logging, etc.) and one whole generation was lost – no Goshawk nests = no Great Grays breeding.

Irruptions (sudden temporary increases in the local population of migrating birds) also occur once in a while when Snowy Owls come that far south because it is a bad lemming year in their home territory. I have seen them both in the Rouge and at the Leslie Spit.

Most owls are nocturnal birds of prey with large heads, flattened faces forming facial disks, and large, forward-facing and immovable eyes. Like hawks, they have hooked bills and hooked claws, and many species have feathered feet. Except Hawk Owls and Snowy Owls, they fly noiselessly, surprising their prey by stealth. Their feather colours are similar for both sexes, but female owls are larger and heavier than males. Owls hunt and eat small birds, rodents, reptiles and fish.

To me the most fascinating feature about owls is their eyes. They are exceptionally large for their body size. An Eastern Screech Owl’s eye weighs 7½ grams; that’s roughly 4% of its body weight. Compare that to a human eyeball, which weighs 28 grams, less than 1% of our total body weight. Among Canadian owls, the largest eyes belong to the Great Horned Owl, Canada’s most widespread species, and the country’s second-largest owl. Great Horneds play an integral role in the stability of ecosystems. They have long, brown or grayish fluffy feathers with conspicuous barring, large ear tufts, huge piercing yellow eyes set in a broad face, and females weigh up to 2 kg. They are year-round residents here, nest in the winter, and incubate eggs well before the snow disappears.

There are many myths about owls. They are well adapted to their lifestyle, but wise they are not. In fact, as bird brains go, they are among the more dim-witted of our feathered friends, way below the intelligence of ravens, crows, magpies and some jays. One myth says that owls can perceive much quieter sounds than other birds. The truth is that owls have sharper hearing at low levels than other birds, but their ability to pick up sounds in the lower range is no better than that of humans. Another myth is that owls can pinpoint the location of a sound with unmatched accuracy, due to the fact that their ears are located on their heads in such a way that one is higher up and the other lower down, to enable stereophonic hearing. But while owls do have excellent pinpointing abilities, those of humans are actually better. Owls do indeed have extremely sharp eyesight and exceptional nocturnal vision, but scientists claim that owls may actually memorize their surroundings in order to avoid obstacles. Most owls hunt at night because that’s when their prey species are most active and because they have no nighttime competition from other raptors, notably hawks and eagles.

Myths or facts, it is obvious that owls are stunning birds. So are the other raptors mentioned above. One can never get tired of watching these superb killing machines and admiring their graceful beauty and awesome powers. They teach us a lot about nature.

Take a walk in one of our many parks, conservation areas or wetlands and watch for Ospreys, colourful Wood Ducks and lovely Pink Lady Slippers among the autumn leaves, or maybe even a turtle sitting on a log to catch a few warm rays of the weakening sun. Embrace the wild joy of living and experience the Fall season in all its glory, when the days become more comfortable and nature is at her most beautiful. Happy hiking! S.G.

Sources: Canadian Wildlife Federation, Toronto and Region Conservation, The Raven (Strickland, Algonquin Park), Ontario Nature, Bird Studies Canada, Owls aren’t Wise (Shedd), Peterson Field Guide of Eastern Birds, and personal field notes.

Wildlife goes and flourishes where there is suitable and supporting habitat. Create a wetland, and amphibians and reptiles will come. Create a garden, and all kinds of critters will show up, from insects, birds, butterflies, beetles, slugs and ants to those migrants from Central America, the Ruby-throated Hummingbirds that love suburban gardens and settle, from May to October, when the living is easy and nectar is in abundance.

This summer, we also found in our garden a Cecropia Moth (see photo above) with a wingspan of 15 cm. This is Ontario’s largest moth, one of the world’s 150,000 moth species that outnumber their day-flying relatives, butterflies, 10:1. They only live a few days and their main activity during that short adult lifespan is mating. During that time Cecropias do not eat at all – they haven’t got time. Male Cecropias can smell a female as far as 11 km away. When they find her they hurry to get things done.

As we all know, there are many areas in the world that support an exclusive flora and fauna. The Galapagos Islands, Australia, and the world’s fourth-largest island off the east coast of Africa in the Indian Ocean, Madagascar, come to mind.

As I found out during my exploratory journey in 2004, Madagascar is a very special place. It is one of the planet’s last great tropical wildernesses, still unspoiled by tourism, and home to 5% of all plant and animal species. More than 70% of them cannot be found anywhere else on earth. What’s more, new species are being discovered all the time – 615 of them just within the last dozen years, according to a recent report from the World Wildlife Fund that is very active in Madagascar – among them 28 new lemur species discovered since 1999.

The island split off from the African continent during the Jurassic period about 165 million years ago — 100 million years before the Rocky Mountains were formed – and it then broke free from India about 85 million years later. Humans moved there only about 1,600 years ago, giving the plants and animals a long time to evolve in isolation. This unique circumstance has inspired some scientists to call Madagascar the eighth continent. In fact, Peter Tyson, the online editor of the PBS series ‘Nova’ and a regular contributor to science magazines, has written a fascinating book about the island with just that title: Madagascar, the Eighth Continent – life, death, and discovery in the lost world of Madagascar (HarperCollins, 2001). I highly recommend it for reading if you are interested in that country’s spell-binding secrets.

One of these is the fact that many animal species never made it to the island. There are no large cats, no jackals, hyenas or foxes, no rabbits, weasels, toads or salamanders. The place of hedgehogs is taken by the tenrec, and there are no adders, vipers or cobras and, as difficult to believe as this may sound, no worms. There are no apes or monkeys on the island either. This creates “niches” taken up by unique species endemic to the island, not only lemurs but also half of the world’s chameleon species, some 800 moth and butterfly species, 115 of the 250 bird species that live on Madagascar, 275 reptile species, and 176 of the 178 frog species, the only amphibians on the island.There are some 10,000 native flowering plants and 130 species of palm trees – more than anywhere else in the world.

And there are no woodpeckers. Their place is taken by the nocturnal big-eyed Aye-Aye who, with the bizarrely elongated middle finger on its hands, extracts larvae and insect grubs from tree bark. It detects its food by listening to the sound of an insect grub chewing its way through the wood. If the Aye-Aye cannot hear anything, it delicately taps the bark, listening with the skill of a piano tuner for the change in sound that indicates a hollow where a larva may be lurking.

Of all the unusual animals that live in the forests of Madagascar, the Aye-Aye must surely be the strangest. On the other hand, the closely related lemurs are decidedly the most adorable. In 2004, there were 51 taxa of lemurs, all 100% indigenous. An international research station for the study of biodiversity (Centre Val Bio) at the edge of Ranomafana National Park, that still has some of Madagascar’s shrinking prime forest, concentrates on lemur research. At least 12 species live in the park, including Sifakas, Red-bellied, Red-fronted, Ruffed Lemurs and three species of Bamboo Lemurs. The park also contains nocturnal Mouse Lemurs, the world’s smallest primates, and Dwarf Lemurs. Originally, there were 67 types of lemurs on the island, some of them as large as a human. Due to habitat loss within the last 1,000 years, eight genera, comprising 15 species, have vanished forever, some disappearing long before humans arrived. The remaining ones vary in size and shape and some of them are very rare and on the verge of extinction. One of the latter is the Golden Lemur; there are only a handful left in the wild. I saw this magnificent lemur (in captivity) at Lemur Gardens just south of the country’s capital, Antananarivo. However, Madagascar still has 33 types of lemurs in the wild.

The largest of them is the short-tailed Indri, which feeds on 80 different kinds of leaves and lives up to 70 years. Indris are reproductive only during the first half of their lives. The second half is devoted to passing on knowledge about food types and sources. Indris mate for life and travel in family groups. The young are born in May, stay two months on their mother’s back, start to discern leaves and to jump when they are about five months old. It takes them two to three months to master perfect landings. But they quickly join their elders in making an eerie racket, a siren-like sound that reverberates through the forest in the early morning hours, as I found out in Perinet.

Brown Lemurs are fruit eaters and often have to travel vast distances because some trees only bear fruit every other year. The diet of Sifakas changes with the season. They often walk upright and sideways on their hind legs, using their long tails for balance. The Ring-tailed Lemurs have feet adapted to rock climbing. You may have watched “Lemur Street” on TVOntario, a delightful series about the lives of Ring-tailed Lemurs. It was filmed in the Berenty Reserve, where I spent a few days and nights with these adorable creatures. I also met them again in Isalo National Park and on Lemur Island, where they frolic amidst other lemur species.

All lemurs are territorial, use scent marks and vocalization to communicate, and have strong family bonds. They are a matriarchal society. Their only natural predator is the Fossa, one of the deadliest carnivors on the planet. It belongs to the mongoose family, and in Madagascar it fills the ecological niche of leopards and cheetahs, although it is only about as large as a fox. It is the island’s top predator and I was lucky to see three of these very elusive and ferocious looking animals in a nature reserve on the island.

Of course, there are no lemurs in the Rouge Valley, although the Toronto Zoo used to have some in the past. But for once I thought I could be allowed to write about animals that are not native. I hope you will agree. Those lemurs stole my heart – and now you know a little bit more about them too.

As mentioned earlier, in Madagascar Aye-Ayes take the place of woodpeckers. But fortunately here we have woodpeckers, mainly the Downy and the similar-looking but slightly larger Hairy, the Red-headed Woodpecker, which I have seen in Algonquin Park, and the magnificent Pileated Wood-peckers, which live in the Rouge Valley. Also belonging to the family of woodpeckers are the Yellow-bellied Sapsucker and the Northern Flicker.

They all find their food in trees by pecking and hammering at the rate of 15 times per second. To stop them from beating their brains out they have “shock-absorber” adaptations that protect their head and neck against impact damage. They also have a relatively long barbed and tubular tongue for penetrating small holes in tree barks to capture their prey. Woodpeckers fill an important role in forest ecosystems by eating vast numbers of bark- and wood-boring insects that are detrimental to the health of trees. Unfortunately, none of the woodpeckers here have yet developed a taste for the larvae of the invasive Emerald Ash Borer. So we must continue to be vigilant.

S.G.

Tidbits and Anniversaries

Forests    In February the United Nations declared 2011 to be the Year of the Forest. In Canada we have good reason to celebrate: Our country is home to 10% of the world’s forests. In fact, half of Canada is covered by trees. Forests are essential to our quality of life. As “the lungs of the earth” forests purify the air we breathe and the water we drink. Forests also provide life-saving medicines, regulate flooding, and help people reduce their energy consumption by shading buildings and screening winds. The net cooling effect of one young, healthy tree is equivalent to ten room-size air-conditioners operating 20 hours a day.

The world’s tallest tree, a Redwood in California, is 124 m high. The largest living thing on earth is a giant Sequoia, also in California, which weighs more than 10 Blue Whales. Some Bristlecone Pines are as old as 5,000 years. They were alive before the Egyptian pyramids were built.

On a worldwide basis, the livelihood of more than 1.6 billion people depends on forests. Forests are home to millions of people around the world and to 80% of our terrestrial biodiversity. In Madagascar, large areas have been deforested, resulting in devastating erosion, although more than 10% of the forest is still standing; prime forest is reduced to only 1%. In Brazil, about 20% of the rainforest has already been destroyed, but there is also some good news: last year, Amazon deforestation dropped to its lowest pace in 22 years, and 80% of landowners in the Amazon must now maintain standing forest on 80% of their property by law. There is still time – not much, but some – to save the world’s forests.

Fish    More good news: during the last five years, three million fish were released into Duffins Creek in Pickering for the “Bring Back the Salmon” initiative of Ontario electric utilities. Ontario Power Generation has agreed to become the lead sponsor in the program to restore a wild, self-sustaining population of Atlantic Salmon to Lake Ontario and its tributaries. The program is managed by the Toronto Region Conservation Authority (TRCA) and the Ontario Federation of Anglers and Hunters in partnership with the Ontario Ministry of Natural Resources.

Birds    Researchers have discovered that the Great Snipe could well be the fastest bird on earth — over long distance at least. After following the birds’ migration south from Sweden to Central Africa, it was discovered that the birds fly nonstop over distances of around 6,760 km at a startling 97 km/h. Many birds fly either very far or very fast, but it is not common for a bird to do both. The Peregrine Falcon reaches a phenomenal 322 km/h, but only while diving to catch its prey. Arctic Terns fly farther than any other bird during their migration – around 80,500 km – from the Arctic to the Antarctic and back again. But they don’t fly at great speed.

Rouge Park    The idea of making the Rouge Park Canada’s first Urban National Park is gaining momentum. It is now on the federal government’s agenda and Environment Minister Peter Kent promised to work out a procedure plan over the summer.

80 years    Ontario Nature, formerly the Federation of Ontario Naturalists, and the umbrella organization for more than 100 naturalists groups, is celebrating its 80th anniversary. Ontario Nature does lots of great work in conservation and deserves all the support it can get.

100 years    Parks Canada turned 100 this year. It looks after 42 national parks, 167 national historic sites, and four marine areas. It was established in 1911 as the world’s first national parks service, 26 years after Banff became Canada’s first national park, followed by Glacier, Yoho, Waterton Lakes and St.Lawrence Islands. The latter is the smallest, while Wood Buffalo is the largest – bigger than Switzerland. One of our newest national parks is Kluane in the Yukon. It contains the largest ice cap outside the polar region and the world’s highest coastal mountains.

Celebrate Canada Parks Day on July 16th.

Sources: Canadian Wildlife Service, Canadian Wildlife Federation, World Wildlife Fund, Nature Canada, Ontario Nature, Bird Studies Canada, Facts and Fallacies (Reader’s Digest), Wild in the City (Bennet and Tiner), The World of Mammals (Taglianti), International Wildlife Encyclopedia, Vol.1 (Burton), Maclean’s, Parks Canada, and travel notes.

After breakfast I sit on a log and contemplate how silly it all is: our rushing through life in undue haste, talking, texting, hurrying, getting caught up in the rat race, fighting and arguing over trivial things, going to war over ideologies, religion, territory, power and resources, killing each other, and shortening our lifespans by unhealthy and unnatural practices.

To shake off these thoughts I decide to go for a walk. The trail leads through the forest, and I marvel at the beautiful trees that do so much for us: they absorb our polluted air and, in return, give us pure oxygen to breathe. They stabilize the soil, reduce erosion, nourish the earth, and provide food and shelter for countless critters. I cannot stop marvelling at the complexity and the beauty of life.

Now I come upon an area where a forest fire had raged a couple of years ago, providing an opportunity for new growth. Many of the dormant seeds have germinated and the seedlings are reaching for the sunlight that is now available, but was denied them before the fire due to the thick canopy of the hardwood forest. And all kinds of animals have moved in to take advantage of the new bounty.

A respectable stand of healthy trees still exists though, and after crossing it, the trail emerges onto a wildflower meadow. There are bloodroots, toothwort, meadow rue, delicate columbines, wild geranium and hepatica, some faded coltsfoot and scilla, a few rare trout lily species, and some marsh marigolds. What a feast of colour and variety!

Bumble bees and butterflies are gorging themselves on the abundance of nectar-carrying blossoms. I see swallowtails and checkerspots, red and white admirals, cabbage whites, sulfurs and a few skippers and fritillaries. The hammering of a pileated woodpecker sounds from the forest I just left, and a few tree swallows circle above, as I watch in fascination the busy activity on an anthill. Now that is a civil society!

I feel a bit peckish and my stomach tells me it’s time for lunch. The trail has led me around a loop and I am soon back at the campsite and start a fire for a healthy midday meal. After eating, I put potatoes in the hot embers of the fireplace so they will be slowly cooked and ready for supper. Then I pick up a book I brought along: Monte Hummel’s Wintergreen, which he wrote over a period of time at his beloved cabin at Loon Lake, “the important place” in his life, as he calls it. I read some of Monte’s reflections on Earth Day, that is coming up in April:

“ … During my long hike, I startled two pairs of mated mallards, who leaped up from a beaver pond, then circled back repeatedly low overhead to investigate what I was. No duck would be so inquisitive and trusting of humans after opening day of the hunting season. But this is only April.

“ A drake wood duck, iridesplendent [sic] beyond belief, lifted off the water in an unconcerned manner to put barely 10 metres between him and me, reluctant to abandon his demure but adoring hen lest a more brilliant suitor take his place.

“ A white-tailed doe casually took her leave, cantering but not bounding, to reappear through the bush three times in a large lazy semicircle, until she was downwind and got a snoot-full of human.

“ A large ruffed grouse jumped up, stirring dried leaves from an oak savanna, waiting until I almost stepped on it before it flushed.

“ A garter snake, fresh from its winter hibernaculum in the rocks, fled instinctively as I cast my shadow on its warm spot in crunchy-dry caribou moss on a sunny ridge. When I froze, trying to indicate no harm intended, it crawled back over my boot toes as if to reciprocate.

“ Painted turtles basked on logs, their surprisingly long uplifted necks yearning for the heat from the solar source of life. Seven of them were lined up, paying homage to their sun god.

“ The very first butterflies (mourning cloaks) fluttered through gray-limbed trunks and branches, with snappy yellow trailing edges to set off their deep-maroon wings.

“ A male sapsucker found a sufficiently hollow limb to startle me by knocking out a reverberating invitation for courtship with any other of its kind within hearing distance. A jay made a sound like a rusty water pump, a flicker laughed, a male ruffed grouse drummed, and when I returned to the cabin, ‘Mrs. Phoebe’ flushed from her nest in the rafter over the front stoop of my cabin. This species of flycatcher returns as early as any to Canada. And this particular family line has returned from points south of Mexico to take up residence on this very spot every spring now for thirty years …”

What a beautiful way of experiencing and describing the marvels of awakening nature! I think about what I’ve read, and as my eyes become heavy, I doze off for a dream-filled siesta. When I wake up, the sun has moved a good bit west over the tree tops. From its position I guess I must have been asleep for the better part of two hours. A glance at my watch tells me that I am right.

Time for another hike. Come along and let’s see what we can discover. This time I take a trail along the creek that eventually ends in a small pond. The afternoon sun shimmers over the still water, a bullfrog croaks in the reeds, and I see a muskrat gather some twigs for its burrow at the far edge of the pond. No beaver dam, but chewed and cut birches nearby are telltale signs of their presence. I know I would have to come back here after sunset, or very early in the morning, to spot them. I remember watching a bunch of them working on a dam in Algonquin Park at about four o’clock in the morning. I also remember watching a pair of phoebes returning each year exactly to the same spot under the eaves of a log cabin in another provincial park. Those flycatchers do that, although I don’t know how.

Squatting at the water’s edge, I think of the abundant life existing in aquatic communities: the plankton, algae, vegetation, benthic vertebrates, fish, amphibians, reptiles, insects, birds and mammals, all inextricably linked to form a chain of mutually beneficial forms of life and survival that characterize healthy ecosystems. Ponds and wetlands are the kidneys of nature.

Sitting at the pond, I also think about the rain cycle, another marvellous example of how nature works.

When water drops out of the sky and hits the ground, it penetrates the earth’s top layer – the zone of aeration – and eventually the bottom layer – the zone of saturation. We know the upper zone as water table and the lower zone as groundwater. Water is essential to sustain the miracle of life. Fortunately, water is anywhere on the planet, in a dazzling variety of forms and locations – oceans, lakes and rivers, the frozen world of the cryosphere that holds water in the form of ice, and the clouds, which are concentrations of condensed water vapour. Water also flows into porous rock and forms underground lakes. This is another repository of water that is so close to us that it’s easy to overlook. It is the groundwater that comprises an estimated 30% of all freshwater on the globe – far more than is held in its rivers, lakes and the atmosphere combined. There are huge aquifers under the desert in North Africa, containing an estimated 260 billion cubic metres of fresh water.

The planet’s rain cycle makes life possible. The transfer of water in all its forms is one of the most complex processes on earth. The system is powered by solar heat, which evaporates water from the planet’s oceans, rivers and lakes. The resulting water vapour is borne by the wind around the globe until local weather conditions cause it to condense into clouds. Then the water falls back to the surface as rain or snow. Rainwater that falls on a body of water is quickly absorbed. Rain that falls on the ground and does not infiltrate the soil is absorbed by plants and trees and then released back to the atmosphere as water vapour, in a process called transpiration. Water that falls on land surface that is too hard to absorb it flows over the ground until it joins a river or stream, in a process called runoff …

( A special exhibit on water opens at the Royal Ontario Museum in Toronto on March 5. During April – Nature Month – there will also be special Friday evening lectures at the ROM about nature in the city. Details about these events are listed on the website www.rom.on.ca/whatson )

Back at the campsite, the neatly stacked firewood begs to be used. I bring it with me, because one should not pick up wood and kindling in the wilderness. Dying wood is there for a purpose: to provide food and shelter for wildlife and to nourish the soil.

Over the fire I heat up some beans and corned beef. The potatoes are already done and only need to be warmed up at the edge of the burning logs. And while I’m eating, a black pot filled with clean brook water quietly comes to a boil for a few cups of tea, enriched with some leaves and hemlock needles I picked up on my hike. As I slowly sip it, some thoughts come to mind: we get so much from nature and we give back so little. We should learn to share it with animals and plants. A few national parks and conservation areas won’t do it; wildlife is everywhere, we are part of nature, and we need to learn to share the space and live in harmony with it, like our native people did in the past.

The tea is finished, the fire is down, and the moon has risen, bathing the place in a mellow, mystical soft light. Time to pack it in. The pesky mosquitos already have. It’s been a good day. I make sure the fire is totally out, crawl into my comfortable, if a bit smelly, sleeping bag, but I leave the tent flap open to see the bright stars in the night sky – and to murmur thanks for the life that gives so much to us; and for the brain that allows us to realize it; and for the good things that we can enjoy and share.

Tomorrow is another day. Life is beautiful. S.G.

“The snow surface, far from being a monotonous blank area of white, is in fact a living ledger in which winter posts its journal entries, occasionally wiping a page clean, then busily beginning another account,” says Monte Hummel in his book Wintergreen. Many beautiful snow traces we can observe on a brisk winter walk are not from animals at all, but from dried leaves blown lightly cartwheeling over the top, and from low-hanging branches that score patterns in fresh snow. There are, of course, all the foot- and hoof prints of animals, too, plus the seed husks, cones and tender twigs that squirrels are perpetually showering on the winter forest floor.

A winter event well engraved on my memory is that of a snowshoe hike over a frozen lake in the Kawarthas. It is an exhilarating experience to “walk on water” on the ice that covers a lake or river. And doing so is irresistible because it provides both ease of travel and an entirely different perspective on the landscape. There is something different about being out there, standing on ice above water and looking back at the land – a view that turns everything around.

Most of our lakes in cottage country are frozen over at this time of the year, and some of the smaller rivers and creeks freeze over as well. When that happens, many changes occur in the water underneath. These changes affect fish, who are cold-blooded. When winter hits, water temperatures cool and in turn so does the fish’s body temperature. Its metabolism also slows, decreasing the rate at which it burns energy and allowing it to live off fat reserves built up over the summer, according to Sarah Jones, a conservation researcher with the Canadian Wildlife Federation. Water conditions change throughout the winter, creating fluctuations in oxygen levels. In November, photosynthesis is still occuring in much of Canada, releasing oxygen into the water. Around December, the conditions worsen as lake surfaces become covered with ice and snow, halting photosynthesis. Organisms and plant matter die and begin to decompose, consuming oxygen and leaving less in the surrounding environment. By January, water temperatures have fallen to near freezing and oxygen levels are beginning to deplete. These conditions worsen during the winter months, threatening fish survival. In March and April, the fish that have survived will begin to move to areas with higher oxygen concentrations. Water conditions improve steadily in Spring and summer and spawning begins.

It’s a different story with our Great Lakes – Ontario, Erie, Huron, Michigan and Superior – which we share with the nation south of us, except for Lake Michigan which is entirely in the United States. These lakes have seldom been covered with ice and if so only for very short periods. With the global warming trend they are not likely to freeze over at all anymore. They are large enough to create their own climate zones and they represent a huge freshwater reservoir on which millions of humans on both sides of the border depend. Here are some interesting statistics about the Great Lakes:

They contain 24 quadrillion litres of water, that’s 20% of the world’s fresh water or 84% of the freshwater supply in North America. Only 1% of it is renewed each year by snow melt and rain. The five lakes cover 244,000 km² and have a combined shoreline of 12,800 km. Some 35 million people live in the Great Lakes area and depend on its water. The Great Lakes Basin is home to 90% of Ontario’s population and the source of 40% of Canada’s economic activity. All living things need water, whether aquatic or terrestrial. A great deal of water is needed to grow food. Growing just 1 kg of wheat requires 600 litres of water, 1 kg of rice 2,000 litres, 1 kg of meat 25,000 litres. A single corn plant absorbs more than 200 litres of water from the soil in just one growing season. Industry also uses large amounts of water; at least 500,000 litres are needed to make one car.

Each year, the Great Lakes facilitate $180 billion to the Canada – U.S. trade. But there is also a darker side: 95 billion litres of untreated sewage flows into these water bodies annually from 20 cities in Canada and the U.S. More of what’s being done about pollution of the lakes later. First, here are some fascinating facts about the largest of the Great Lakes, Lake Superior:

It contains 10% of all the fresh water on the planet. It covers 82,400 km² and its average depth is 147 m. Superior contains as much water as all the other Great Lakes combined, plus three extra Lake Eries. More than 300 streams and rivers empty into Superior. The lake was formed during the last glacial retreat, making it one of the earth’s youngest major features at “only” 10,000 years old. Some of the world’s oldest rocks, formed about 2.7 billion years ago, can be found on the Ontario shore of Lake Superior. It very rarely freezes over completely, and then only for a few hours. That happened in 1962, 1979, 2003 and 2009.

For many people the perception of the Great Lakes is one of water coloured by toxic pollution, concerns about drinking water safety, and advisories about what fish are safe to eat. There is good reason for that. During the last two centuries, 163 non-native aquatic species have been introduced to the Great Lakes. Aggressive species can spread quickly, changing the very make-up of their new habitat and driving out native species. Zebra mussels, sea lamprey, round goby and Asian carp have become ubiquitous reminders of what can happen when plants and animals are brought to the Great Lakes from the far reaches of the earth. Invasive species like these have no predators to keep them in check, allowing their numbers to explode and causing serious damage to the natural ecosystem.

So, what can be done about the pollution of those waters? What about our stewardship of this treasure? Our health, as well as our industrial activity, is irrefutably connected to the health of the Great Lakes. Past and current neglect of this ecosystem has led to major changes in water quality, deterioration of coastal habitats and the loss of native fish and other wildlife. The Great Lakes ecoregion supports the greatest species diversity in Canada – something to think about in this ‘Year of Biodiversity.’ Dunes, cliffs, wetlands and forests can all be found along the shores of these five lakes. Here, land and water are not separate but linked. We tend to think that land and water are two different things, but the truth is that these two principal ecosystems are indivisible: through the water cycle they combine to nurture all the living things found within the planet’s biosphere.

One organization, the Nature Conservancy of Canada (NCC), is deeply committed to conservation efforts, from the northwestern shores of Lake Superior to the southernmost islands of Lake Erie, and across the eastern end of our province where Lake Ontario connects to the St. Lawrence River. Completed in 2009, the NCC’s Lake Ontario Biodiversity Conservation Strategy offers a binational plan to protect and restore, to the fullest extent possible, the native biodiversity and critical natural processes of Lake Ontario. Together with experts from Canada and the United States, representing more than 50 agencies, NCC focuses on a conservation strategy which includes the identification of key biodiversity targets, such as migratory fish, aquatic habitats and coastal wetlands.

In a recent assessment of the environmental health of the Great Lakes, Ontario’s environmental commissioner Gord Miller criticized the provincial government for inaction, saying that municipal wastewater discharges are increasingly adding to pollution of the Great Lakes because the rules of the environment ministry don’t factor in the growing population of Southern Ontario. He said dumping from illegal mining camps in the Far North is also increasing, and he blames the province for failing to follow through on its environmental promises.

There is more action on the U.S. side of the border. The Obama administration has developed a five-year blueprint for rescuing the Great Lakes ecosystem, including clean-up, wetland restoration, and a zero tolerance policy for invasive species, including the devastating Asian carp. The plan will require US $2.2 billion for long-overdue repairs after a century of damage to the lakes, according to the head of the U.S. Environmental Protection Agency. The plan also includes water quality improvement in shallow areas, where runoff from cities and farms has led to algae blooms and beach closings. There have been efforts in the past, and Lake Erie has made a remarkable recovery already. But much remains to be done, and the above shows evidence of at least some plans. Let`s hope they will be carried out.

My winter thoughts have meandered, but that always seems to happen when I think about nature, where everything is interconnected and inextricably linked. Winter can teach us a great deal. Make the most of it. Soon it will be Spring again – and time for another Nature Note on awakening wildlife and on the planet`s water cycle. Happy ice fishing and snowshoeing! S.G.

Sources: Monte Hummel, Wintergreen; Sarah Jones, Canadian Wildlife Federation; William Andrews, Discovering Biological Science; R.D. Lawrence, The Natural History of Canada; Nature Conservancy of Canada; Ontario Clean Water Agency; Great Lakes United International Coalition; Ecojustice; Google and personal files and news releases.

And that doesn’t even touch on the other great fact about oceans: the food chain. Oceans are the crucible of life.

Our oceans are in trouble. They are vulnerable to our actions. Shifts in chemicals caused by massive pollution drastically change the life support system of our waters. We are losing the integrity of a system that we don’t know how to put together again. And scientists tell us that we only know about 5% of what goes on in the oceans. How can we not want to know more?

As everything in the universe is connected and interrelated, let’s review a few facts about where all life starts: the “small stuff” in the oceans. To really grasp what drives the productivity of ocean waters, that are packed with life, one has to view the sea on a small scale and look at the minutiae of life – plankton. The story of the plankton is the story of a great feast. This is where the food chain starts.

Plankton – microscopic and primitive drifting organisms in the sea or fresh water – are some of the most important and fundamental organisms on our planet. They form the base of the majority of aquatic food chains. (The word “plankton” is derived from the Greek planktos, meaning wandering or drifting.)

So, what are plankton? A floating organism that inhabits oceans, seas, and bodies of fresh water; anything from as little as 1/10,000 mm in the case of marine viruses to 20 cm and more in the case of marine organisms, such as jellyfish.

Plankton are generally divided into three broad levels:

1. Phytoplankton – tiny plants that are hugely important to the productivity of seas as they act as the primary producers in the oceans. Like terrestrial plants, they are able to extract energy from the sunlight that penetrates the water, using photosynthesis to produce organic matter from carbon dioxide and manufacture oxygen in the process.

2. Zooplankton – the first consumers of the food chain. They comprise small “grazing” animals that eat phytoplankton and prey on small organisms and other zooplankton. The zooplankton of south-east Alaska, for instance, are vitally important to the ecology of that state as they feed the herring which fuel the entire ecosystem there.

3. Bacterioplankton – they act as the recyclers of the plankton world, consuming and converting organic material produced by other organisms back into inorganic nutrients.

Plankton are the critical components of food chains in all marine environment. Oceanic phytoplankton are the primary food source of nearly all sea organisms. Phytoplankton vary seasonally in amount, increasing in Spring and Fall, with favourable light, temperature and minerals.

To fully understand the plankton world, another concept needs to be introduced here: boundary systems. These are characterized by the presence of large plants in the open waters of oceans and big lakes – such as the Great Lakes – where the basic production of living material is carried out by phytoplankton floating freely in the water. At the bottom there is not enough light to allow the growth of large, attached plants, but in the boundary area between very deep and more shallow water there is a level of productivity that increases in areas closer to the surface. For example, the high level of plant production in estuaries supports a correspondingly high level of production of invertebrate animals and fish, as well as shellfish (mussels and oysters) and large populations of shrimps and crabs.

Another interesting phenomenon is that the ocean’s tiniest inhabitants – plankton and bacteria – can cause the sea to glow. This is sometimes seen in California’s “red tides” as well as in Bioluminescent Bay off the island of Viegues in Puerto Rico.

There is much to learn. The international census of marine life, the compiling of which has taken 10 years and the involvement of thousands of scientists from 80 countries, is still a work in progress. The effort to catalogue every living thing in the oceans has already resulted in listing more than 110,000 species, but scientists say that is only a paltry 20 to 40% of ocean life. A report is due to be published this October. Canada, with 2,636 species being catalogued in its Pacific region, 3,160 species in its Atlantic area, and 3,035 species in its Arctic region, has contributed a large chunk to the study of examining underwater biodiversity in order to understand how the oceans are threatened by human activity. Let’s hope that better understanding will lead to a greater protection of this important realm.

In a recent article about the cataclysmic disaster in the Gulf of Mexico, two Canadian journalists living in Louisiana, Joseph and Amanda Boyden, have emphasized the work of Dr. Joe MacInnis, a Canadian physician-scientist, author and famous deep-sea explorer who, along with his friend James Cameron, has led numerous Titanic explorations. MacInnis writes of the oil plume’s damage, saying that the cell-swarm of killing continues to the phytoplankton, the lungs of the planet. He says, “Trillions upon trillions of dead diatoms and dinoflagellates rain down through the filthy procession of upward-moving oil. In deep water they merge with uncounted corpses of copepods and in deeper water still, with the lifeless remnants of big fish, small fish, turtles and invertebrates. The deluge of megadeath continues until these remains come to rest on the gaunt floor of the Gulf.”

To demonstrate how interconnected the sea is with everything else on our planet, let’s take a brief look at sea otters, those cute but endangered species that are one of Mother Nature’s best animal carbon sinks. They can pull up to 0.18 kg of carbon dioxide out of the air for every square metre of water they occupy, simply by keeping kelp beds healthy. The current population of sea otters is only about one-third of what it was before they were hunted to near extinction in the 18th and 19th centuries. If they were the 300,000 animals known before that, they would be responsible for the sequestration of about 10 billion kilograms of carbon dioxide a year. Sea otters help kelp beds by eating sea urchins which are devastating the carbon-sucking kelp because of their population explosion in areas that used to be otter stomping grounds. As a result, a huge amount of carbon dioxide stays in the air. There are now not enough sea otters to balance the system. So, can they make a comeback? Their gene pool is now very small, and that, unfortunately, makes conservation efforts difficult, according to a science team at the University of California. Every time we mess with nature, we upset the equilibrium. Will we ever learn?

There is no doubt that a lot more work is ahead and that the future is in marine biology. Many new life forms are waiting to be discovered. And they are all interconnected. Our oceans are the hot spot of biodiversity. Fascinating discoveries await. So, where to start? It seems that a good way to launch scientific exploration would be to try and learn more about the ocean currents and to unravel the complex mystery of coral reefs. To me, exploring the oceans on our own planet makes more sense than spending billions of dollars on outer space technology. We have so much to learn right here on Earth! S.G.

Quick Facts

Monarch Butterflies hatch in mid-summer and in the Fall the adults fly 3,000 km to Michoacan in central Mexico where they overwinter and breed. The offspring are the ones that fly to Canada in the Spring. There are two distinct Monarch populations in Canada: a large population found east of the Rockies, and a much smaller western population found only in central British Columbia. Their breeding range closely reflects the distribution of milkweed species.

Peregrine Falcons are the fastest birds in the world. When they are hunting, their dive can reach speeds of more than 300 km/h. Due to widespread use of pesticides they were close to extinction. But after DDT was banned they made a remarkable comeback. Many pairs are now successfully breeding in eastern Canada.

Tree Squirrels have sweat glands on their feet. When hot or excited they will leave wet tracks on a dry surface. The sweat glands also produce a scent which the squirrels use to mark the trees in their territory.

Frogs live for at least three to five years, depending on the species. They keep their skin wet to breathe. Amphibians get oxygen through both their skin and their lungs. If you must handle frogs, make sure that your hands are free of insecticides, perfume, spray and sunscreen lotion. In winter, frogs find refuge in leaf litter, in the mud in the bottom of lakes and wetlands, or in burrows under rocks and logs beneath the soil.

Wood Ducks find their mates in January and arrive at their breeding grounds in the Spring already as a pair. This species is one of the few North American ducks that nest in trees, usually in a cavity close to water.

It’s a happy time for wildlife – IF the habitat is there. But what happens if it ISN’T there? When it is altered or destroyed by human activity or shifting because of climate change?

This is happening, and it affects many creatures, especially those that depend on grasslands habitat that is rapidly disappearing, as I outlined in my Nature Notes of October 2008, titled Our Disappearing Grasslands. It is happening not only because of urban sprawl and industrialization, but also because of global warming. How so?

Let me illustrate that by the plight of one of our loveliest meadow birds, the feisty and charming Bobolink. These grassland birds build their nests on the ground, hidden in long grass.The females lay three to seven blue-gray eggs, speckled with reddish-brown dots. Incubation takes about 13 days. Hatching occurs between June 7 and 20. The young birds leave the nest before they are ready to fly, at about 10 days old. They are not capable of sustained flight until they are 16 days old.

Things were going beautifully for the Bobolinks until agricultural practices changed in the latter part of the 20th century. Farmers began harvesting their hay more frequently and earlier. Today, cutting dates occur two or three weeks sooner than they did 40 years ago. They now happen in mid- to late June, right around the time when the Bobolink`s eggs hatch and the tiny newborns are at their most vulnerable. According to the Canadian Migration Research Foundation (www.migrationresearch.org) about 96% of eggs and nestlings are now destroyed during early hay cropping, either killed by mower blades or scooped up by gulls and other predators when the protective grasses are cut. The good news is that by delaying cutting by a week or 10 days, you go from zero nesting success to a success rate of 80% or more. It would be a significant thing for farmers to do, and some are doing it. That’s encouraging.

Other birds, too, are under pressure from changing agricultural practices. They include the Grasshopper Sparrow, Eastern Meadowlark, Henslow’s Sparrow, Vesper Sparrow, Sedge Wren, Horned Lark, Upland Sand-piper, and the Whip-poor-will. Also among endangered bird species are the Lewis’ Woodpecker, Sprague’s Pipit, Whooping Crane, Acadian Flycatcher, Flammulated Owl and, of course, the poor Bobolink. More than 25% of the Bobolink’s breeding range is in Canada and the species has declined by 88% since 1968.

The Bobolink joins a lengthy and growing list of birds, insects and other wildlife depending on grassland habitat, that are designated “at risk.” As with other grasslands species, the declines are widespread and severe. For instance, Eastern Loggerhead Shrikes are declining across much of their range. This subspecies is critically endangered. The majority now breed in Ontario where a captive breeding program has been releasing about 100 shrikes annually since 2006.

Many animals affected by disappearing habitat are migratory, from Blue-spotted Salamanders and Black-footed Ferrets to the hundreds of bird species that fly to Canada each Spring from thousands of kilometres away. The Golden-winged Warbler, for example, overwinters in Central and South America. Up to 50,000 couples return to Canada each year to breed. The little casanovas prefer to come to the same site year after year, like phoebes, usually along hydro wires, fencelines and regenerating forests in Ontario, where low bushes and shrubs provide shelter for their nests, which they build on the ground, like Killdeers and Bobolinks.

You might imagine, writes Megan Findlay in a Canadian Wildlife Federation newsletter, that a bird that is sturdy enough to migrate thousands of kilometres a year could withstand most threats. But the Golden-winged Warbler, like many other neotropical birds, is in a perilous situation. Habitat loss is forcing its close relative, the Blue-winged Warbler, to move out of its normal breeding grounds to the north-eastern U.S. and into Canada. Studies show that the Golden-winged Warbler’s arrival stops locally within 50 years of the Blue-winged Warbler’s arrival as a result of overcrowded breeding grounds. Since the mid-1990s, the Golden-winged Warbler population has declined by 79 per cent.

The statistics of decline are alarming for our subject species as well. The biggest drop in the Bobolink population in the last decade is right here in Ontario – an average of 2.6% a year. We’re losing a very beautiful songbird.

Here is what freelance writer Cecily Ross says about this fascinating avian in the summer edition of ON Nature: “Male Bobolinks arrive in Ontario in mid-May and set about establishing their territories in open fields. Females join them a week later. Males defend their turf aggressively by singing and chasing away rival males.

“Bobolinks are a highly dimorphic species, i.e. the males and females look very different. During the breeding season, males are a sleek black with a yellow head patch and bold white patterns on their backs. However, before Fall migration they moult into a nondescript striped brown plumage like that of the females. The summer diet of Bobolinks consists mainly of insects, including beetles, grasshoppers, caterpillars, ants, wasps, spiders and millipedes. They also eat some weed and grass seeds. During migration, they feed heavily on rice and millet and are considered a major agricultural pest in regions where these crops are grown. The species are one of the few songbirds that have two moulting periods. One occurs at their wintering grounds in South America, beginning in late January. The second moult takes place in late July when the males revert to basic brown.

“The plucky Bobolink has the longest migration route of any songbird. In July and August, males and females fatten up on seeds before embarking on the long and treacherous journey to their wintering grounds in the pampas of southern South America, a round trip of approximately 20,000 km. On the way, the birds run a gauntlet of hazards, starting with angry rice farmers in the southeastern U.S., where they are shot and poisened in the hundreds of thousands. In Jamaica, the seed-fattened Bobolinks are called butterbirds and are hunted and sold in the local markets as food. Farther south, the birds are prized for their beauty and effervescent song, and are caged as pets in the fashionable salons of Buenos Aires and Lima.”

We used to see and hear Bobolinks in the meadows of the Rouge Valley, but lately such sightings have become very rare. It was a thrill to listen to their joyous song, a bubbling cacophony of harsh and sweet melody floating over breezy meadows from one of nature’s most eloquent harbingers of Spring. But Bobolinks are not entirely gone yet. A good place to see them, and other grassland birds, is the Carden Plain, a rare alvar habitat where you can also still find Henslow’s Sparrows and Eastern Loggerhead Shrikes. Carden Plain is about two hours’ drive north from Toronto near the Kirkfield locks of the Trent Canal. It is on Hwy 48 and there is also a website for it: www.cardenplainimportantbirdarea.com where you can find information about the 238 bird species, 142 butterfly and dragnonfly species, and 450 plant species that inhabit the alvar.

To find out more about Bobolinks, you can visit www.migrationresearch.org/research/grasslands.html or  www.bsc-eoc.org or www.ofo.ca

There is also a book I can recommend: in Grass, Sky, Song – Promise and Peril in the World of Grassland Birds, Trevor Herriot, (HarperCollins, $23) a leading prairie naturalist, meditates about the fate of Canada’s grassland avians.

Birds, mammals and amphibians are all struggling to survive in a dramatically changing world. There is a clash between nature and human activity. Remember that everything in nature depends on the availability of food. Animals cannot import food from all over the world as we humans do. They must do with what is available around them. In the quickly warming Arctic, where the average temperature has risen by 2°C in the last two decades, food options are already decreasing and predators are going hungry. Snowy Owls, on top of the food chain, are especially hard hit by the dearth of lemmings as the web of life is unravelling and a thousand-year-old equilibrium is thrown out of kilter.

MOSQUITOS … don’t have feathers but they do have wings – and a long proboscis stinger that females use to puncture the skin of animals and humans to suck blood, which they need during their reproductive cycle. In the process, unfortunately, they also transmit diseases, such as the West Nile virus. They prefer to breed in shallow, temporary pools, ditches and wetlands, where they can feed on bacteria from the water.

By dictionary definition, they are a biting insect of the genus aedes. Nature lovers know that they can be a nuisance on bush trails and in campsites. Nevertheless, they can – and should be – loved too. After all they pollinate wildflowers, such as our White Trillium. These marauders, also known as skeeters, can detect humans up to 30 m away and are also attracted to plant juices, nectar and honeydew.

Mosquitos live anywhere from one to 12 months, depending on the species, and they do have a great number of predators, adding to fly swatters and insect repellents: bats, swallows, swifts, nighthawks, flycatchers, warblers, frogs and toads, dragonflies, wasps, spiders, and some beetles and aquatic insects.

That severely reduces the chances of being bitten by a mosquito. And there is also this: there are hundreds of mosquito species worldwide, but only 34 in Canada and just about a dozen in Ontario. And only the females sting when they are breeding. So what’s the problem?

If you are still fretting about mosquito bites, there is a very simple way of keeping the pesky insects away when you are hiking or camping: place a dryer sheet in your pocket. It really works.

Enjoy the summer, delight in the frolicking of our feathered friends, ignore the mosquitos, and look for the next Nature Notes in two months. It will be on quite a different subject. Happy hiking! S.G.

Sources: Ontario Nature, Bird Studies Canada, Wild Birds Unlimited, Wild City, Toronto the Wild, Canadian Wildlife Federation, and personal field notes