The Environmentalists' Paradox

This column was published in the Cranbrook Daily Townsman Tuesday September 21, 2010.

A long standing environmentalist tenet holds that humans are living beyond our global means. It states resource depletion and ecosystem degradation will, sooner or later, bring about our ultimate demise. There is no lack of data available to support evidence of ecosystem decline. Be it salination or drying of water bodies such as the Aral Sea, collapse of fisheries (think Atlantic cod), musings on peak oil or deforestation, many argue that we’re destroying our home and native planet.

Yet rumours of our imminent demise are greatly exaggerated. Recent measures suggest the average human condition has not only avoided decline in the face of such ecological troubles but is actually improving. Estimates of a Human Development Index (HDI) based on life expectancy, literacy, education and gross domestic product indicate that the average human condition in every major region of the world has increased over the past thirty years.

Estimated "Human Development Index" as calculated by United Nations Development Programme in 2006. Source: Raudsepp-Hearne et al. 2010.

A paper (abstract available here) in the September issue of BioScience terms this “the environmentalist’s paradox.” The authors, scientists at Montréal’s McGill University led by Ciara Raudsepp-Hearne, ask “How is it that human well-being continues to improve as ecosystem services decline?” They offer four hypotheses to explain the paradox:

The four hypotheses are:
1. Critical dimensions of human well-being have not been captured adequately, and human well-being is actually declining.

2. Provisioning ecosystem services, such as food production, are most significant for human well-being; therefore, if food production per capita increases, human well-being will also increase, regardless of declines in other services.

3. Technology and social innovation have decoupled human well-being from the state of ecosystems to the extent that human well-being is now less dependent on ecosystem services.

4. There is a time lag after ecosystem service degradation before human well-being is negatively affected. Loss of human well-being caused by current declines in services has therefore not yet occurred to a measurable extent.

The authors cite sufficient data to reject the first hypothesis, stating “Most well being indicators… [show] that human well-being is, on average, growing.” Agree with it or not, global human condition is better. Turns out the “good ‘ol days” weren’t so good. No doubt some human populations are worse off, but the authors examined whether data lumping might mask key declines. Not so: the HDI is increasing across the board.

The second hypothesis is generally supported. Our ability to produce food currently outweighs declines in other services provided by ecosystems, such as water quality and quantity and forest cover. Again, measurements are at the global scale so localized impacts that directly affect human well-being should be considered. Examples include losses coral reefs that support fisheries and wetlands that provide flood protection.

For the third hypothesis, the authors conclude there is not enough evidence to suggest a de-coupling of humans from nature. Rather than replacing ecosystem services, technology has tended to extend them. We’re still dependent on natural products from ecosystems but more generally efficient in their use.

But our prospects are not propitious, for technology and resources both have limits. One report estimated that 40% of all protein in human diets depends on nitrogen fertilizer produced from fossil fuels. We are largely living off the capital of millions of years of biological accumulation on Earth.

The fourth hypothesis is perhaps the most intriguing. Are we experiencing a lag between ecosystem degradation and its potential to affect human well-being? Can we expect a visit from the “ghost of collapse-yet-to-come”? Here, the authors waffle. Theory strongly supports the existence of a lag, but they could find little actual evidence. Instead, they caution that “changes present new challenges to humanity” but admit actually measuring this is crazy difficult.

They conclude that we are having “an unprecedented effect on the biosphere,” but only “weak evidence” suggests that such impacts are “reducing aggregate human well-being at the global scale.” The paradox stands for now, but the authors don’t seem convinced that it will hold up long-term.

Stink Bugs: An Autumn Ritual

This column was published in the Cranbrook Daily Townsman, Thursday October 21, 2010. 
 
Autumn. Time for one of those Kootenay traditions that celebrates warm afternoons and cool nights. That’s right, it’s the season again to patrol the outside of the house and flick stink bugs off the deck, chairs, door, walls and apparently every other possible surface. Those that find their way indoors need to be gently evicted. Careful moving them, they’ve got a loaded rear end to make any warthog or skunk jealous.

For good fun, watch the dog catch one, get a mouthful of the bug’s foul discharge then try to clean it out. A smart pet will only do that once. One of our own spring rituals is to open the deck box that holds our outside chair cushions and shake out the dead stink bugs that have lain entombed and frozen throughout the winter. Deck boxes make a poor hibernation choice for insects.

Stink bugs are more properly called Western Conifer Seed bugs (Leptoglossus occidentalis) and are native to the western United States but have been increasing their range through the last century. They are now found throughout eastern North America as well as accidental introductions into Europe (and probably elsewhere), hitching rides on Christmas trees and other forest products.

They move through a single life cycle each year, overwintering as adults before emerging in the spring to feed on developing seeds in green cones. Females then lay neat rows of eggs on conifer needles as their final act. The eggs hatch and successive larval stages continue to feed on the cones and needles of the trees until the adult stage is reached by late August.

And then the fun begins anew. South and west-facing walls and homes make welcoming places to adult stink bugs looking to keep warm. As the nights cool, the bugs will push farther in their search for warmth. No crack or opening seems to narrow for them to fit through. Their body seems almost two-dimensionally thin and they are able to squeeze through any seal not quite air-tight. Think of them as friendly reminders to check your door and window seals.

There is no need for alarm if they are found inside. They do not bite, for their mouth parts are adapted to sucking tree sap from cones, not biting or chewing. Their only downside, apart from those squeamish about insects in the home, is the foul odour they emit if disturbed. Thus the ‘stink bug’ moniker, one well earned. Crushing them is not advised, even picking them up can result in an unfortunate olfactory experience. Encourage them to move onto a piece of paper, then release them back outside.

The insects are entirely harmless, unless you’re running a tree nursery and trying to gather seeds from conifer trees. They can cause significant losses in seed production by adult trees by feeding on developing cones and occasionally killing the tree itself.

How they find these cones was described by Simon Fraser University biologist Stephen Takács. His team found that growing conifer cones are much warmer than the surrounding vegetation, up to 15º C! (see paper here.) To infrared sensors, a conifer with growing cones appears like a Christmas tree, with each cone brightly “lit” relative to the adjacent greenery.  

Turns out, stink bugs have highly sensitive infrared sensors in their abdomens, directly connected to their brain. When biologists blocked these sensors, seed bugs could no longer find the trees. This attraction to high intensity infrared radiation also explains why the bugs are so drawn to warm, sunlit walls during the autumn.

Ultimately, all the bugs are doing is looking for a place to spend the winter where they won’t freeze to death. As the weather cools and winter looks to set in, that’s something we can all relate to.

Conifer tree under visual and infrared light showing warmer temperature of cones

Appreciating the Urban Wild

This column was published in the Cranbrook Daily Townsman Tuesday October 12, 2010.

Confessing to being a Toronto native to those beyond the 416 area code can be dangerous. Admitting you’re from the city the rest of the country loves to hate, with its smug self-importance, can still elicit reactions from surprise to disdain.

But as time increases from my Toronto address, I’m comfortable enough to go public: I am proud to be a Toronto native. In one of those rites of aging, I recently returned to the big city for my 25th high school reunion.

I had not previously thought of myself as the high school reunion type. I wasn’t exactly the school social coordinator. Most of my youth was spent trying to escape the city in search of a more rural, if not outright backwoods, existence. Summer jobs took me to bush camps across northern Ontario from Algonquin Park to Lake Abitibi, Moosonee and beyond.

So returning to Toronto to reconnect with a few friends and classmates long since forgotten was not something I would have predicted even ten years ago, let alone when I finished high school.

One product of my youthful dreams of a northern idyll was the belief that the only natural world worth experiencing was true wilderness. What exactly constitutes “wilderness” is debatable, but most conclude that it involves a lack of immediate human presence. More strident definitions also require an ‘untouched’ quality where one might indulge the illusion that few, if any, humans have previously visited.

For me, wilderness lay at least two portages removed from overcrowded canoe routes or well off the main hiking trail. Certainly, wilderness wasn’t to be found in suburban Toronto or any other city. But closing one’s eyes to natural areas within urban cities is to miss many wonderful places.

While in Toronto, I found myself with an hour’s wait at my nephew’s high school in the city’s west end. A large old brick school that his grandfather attended set in a typical Toronto neighbourhood of narrow lots on streets lined with mature hardwood trees.

I happened across the “Hillside Nature Garden” at the adjacent Runnymede Public School. Students restored a narrow slope around the school with native trees, shrubs and wildflowers. A trail runs through the strip of natural cover, maybe fifty metres wide at best.


 

Hillside Garden Project (outlined in red) at Runnymede
Public School, Toronto. Ursula Franklin Academy & Western
Tech High Schools are in upper right corner. from Google Earth



Hardly wilderness by anyone’s definition, it likely supports little more than a few bird nests, the odd raccoon and a few voles. But here, sumac, sycamore and sassafras trees provide shade and cover to a piece of ground that otherwise be mowed lawn, a weed source or a cement retaining wall littered with lunch wrappers and unfinished homework.

More importantly, it provides a wonderful natural classroom to the school’s young students. To many, that small patch of green likely serves as an introduction of the world beyond concrete and computers.

Statistics Canada state that 80% of Canada’s population lives in an urbanized centre of more than 1000 people. By that measure, Sparwood, BC, (population of roughly 4000) is as urbanized as Toronto. But nonetheless, the measurement indicates the degree to which our population lives in developed centres. Urban-rural splits are becoming major political wedges (witness the recent longun registry ballyhoo) with the main complaint of the rural and small community dwellers being that urban folk don’t understand the non-synthetic world beyond city limits.

Natural areas, even small ones like the Hillside Nature Garden can serve as an introduction to city children who may not otherwise have an opportunity experience nature first hand. Through planting and caring for native species rather than nursery-bred exotics, hopefully a better appreciation for our natural world may also be sown and fostered.

Even in smaller urban centres like Cranbrook, with true wilderness at our doorstep, many children have no introduction to the natural world. School programs like Wild Voices for Kids and trips to the Blue Lake Centre should be required curriculum components. The objective isn’t to turn everyone into a wilderness loving environmentalist, but broaden overall experience and appreciation of our world.

Trouble for the Food Supply

This column was published in the Cranbrook Daily Townsman Tuesday September 21, 2010.



So how did your garden do this year? Generally cool temperatures have kept many tomatoes green and not helped many crops, especially berries. On the other hand, cool and regular showers has our lettuce still going strong when it is normally virtually toasted by early August. We’re enjoying a second go-round of peas and were enjoying a bumper crop of beans until the frosts of early September took them out.

But more than just good weather and careful tending is required to pull off a successful garden. Many crops, wildflowers and other plants are reliant on insects for pollination in order to successfully bear fruit and viable seeds. Bees provide the vast majority of these pollination services to agriculture and natural ecosystems. Honey bees can increase yield in 96% of animal-pollinated crops and insect pollination in general (mostly bees) is necessary for 75% of human crops worldwide. If you like berries, coffee, nuts and other foods, you want bees.

But recent declines in bee populations around the world raises significant concern for the future for both agricultural productivity and wild plant communities. The majority of agricultural and apicultural (bee keeping) scientists now agree that significant declines have occurred in honey bees world wide. Some estimates suggest a 59% loss of honey bee colonies in the USA between 1947 and 2005.

And domestic bee populations decline, what is going on in wild bee populations are also thought be suffering widespread losses. Recent work in Illinois found half the bumblebee species there were either extirpated (no longer existing in certain areas, but present elsewhere) or had suffered declines. The trouble is we don’t know much about wild bees. To document a decline you need both current population estimates and from some time in the past. We just don’t have much of that data. Where the data are available, the news is not good.

A recent review of pollinator declines, published in the journal Trends in Ecology and Evolution, reports on evidence of the decline and what is driving it. Habitat loss is indicted as a key driver of wild bee declines. As natural ecosystems are urbanized or otherwise altered, most native bees suffer along with other wildlife species. Hand-in-hand with bee declines are losses of plant diversity. In some cases this becomes a chicken-and-egg scenario. Many plants rely on bees for pollination and reproduction and vice-versa. If one is removed from the ecosystem the other also fails. Trying to figure out which declined first is difficult and not always

Electron micrograph of Varroa destructor mite on a honey bee

Intensified agricultural activity is another driver. Insecticides in particular kill bees directly, while herbicides and fertilizers are implicated as reducing food availability to bees and other pollinators.

One cause of bee declines that has received media coverage is the introduction of a parasitic mite from Asia. The Varroa mites latch on to bees and feeds on the insect’s hemolymph (essentially insect blood). Further weakening the bee are various viruses transmitted by the mite so that entire bee colonies can be wiped out. Some estimates suggest that all feral honey bee colonies in the Europe and the United States have disappeared as a result of Varroa mites.

Varroa mites on honey bee pupae.

Climate change may also impact bees. Mismatches in bee emergence and plant flowering can result in reduced productivity for both bee and plant. All these drivers may act independently or in an additive effect that combine to drive local declines farther and faster. The consequences for agricultural and food production are significant, though they can rent travelling honey bee colonies at the time when pollinated is needed most.

Most home gardeners can’t justify that level of cost. Worrying about late and early frosts is enough of a challenge. Adding in doubts about whether your garden will be pollinated is just one more uncertainty.  

Wildlife Migration and the Green-Up

This column was published in the Cranbrook Daily Townsman Tuesday September 14, 2010.


Last week, I wrote about the trade-off that elk and other ungulates make between predation and forage. Many animals are forced to make decisions between accessing high quality food and exposing themselves to higher predation risk. Ungulate species around the world have evolved migration as a strategy to lower predation risk and access higher quality forage.

The issue of non-migratory or resident elk living year-round in the valley-bottom Trench has vexed wildlife managers and ranchers alike. The number of elk migrating to the high country each summer has declined significantly. As efforts continue to encourage elk to resume their seasonal wanderings, new challenges may arise in this effort.

Migratory ungulates in the Rockies follow a spring wave of green-up into the mountains, feeding on nutritious and highly digestible emergent vegetation. But constraints on food availability may hinder elk in the high country compared to their non-migratory cousins who stay put in the Trench. It all ties into plant growth.

Dr. Mark Hebblewhite at the University of Montana notes recent research that suggests changes in historical vegetation growth patterns may further disadvantage migrating elk. He notes that “climate change might potentially lead to reduced benefits for migration” (emphasis his).

If plants grow too quickly, forage quality is reduced. Slow-growing, cool springs keeps grasses lush, digestible and highly nutritious. Conversely, short, rapid-warming springs quickly dry out vegetation with a loss of nutritional value. Research on bighorn sheep and mountain goats in Alberta has shown that compressed green-up can directly reduce lamb and kid survival. It’s not a long stretch to other species using similar habitats and diets: elk and mule deer.

Evidence suggests changes are occurring in high elevation vegetative growth patterns. Global land plant growth increased 6% between 1982 and 1999, with the increase accredited to higher temperature, more rain and solar radiation; all key ingredients to plant growth. When University of Montana scientists Maosheng Zhao and Steve Running set out to update the research, they were astonished to find the same global terrestrial plant growth rate declined, albeit slightly at 1%, between 2000 and 2009. Their research, published in Science last month, found that drought has outpaced temperature increases, particularly in the southern hemisphere, and led to net declines in plant growth in many areas of the world. Elsewhere, including most northern latitude forests such as Canada, net plant growth is still increasing. But the work issues a warning that climate change can cause unexpected and rapid shifts in ecological systems.

A third issue is termed the “trophic mismatch hypothesis,” first described by Penn State’s Eric Post and colleagues for caribou in Greenland. There, changes in green-up time are creating a mismatch between calving times and food availability. In a harsh arctic or high elevation ecosystems where food is often scarce outside a short growing season, timing of birth is very important.

Some estimates place the energetic costs of lactation at some 200% more expensive to mothers than pregnancy. So having an abundant, nutritious food source while young are nursing is essential. Even slight shifts in forage availability is enough to lower calf survival. Whether the same phenomenon is occurring in alpine ecosystems is unknown. It’s a question Dr. Hebblewhite would like to test in the Rocky Mountains.

Timing of ungulate migration is a complex adaptation to various clues. Their ability to respond to change lags well behind plant growth responding to seasonal climate shifts. If changes are indeed occurring in high elevation montane forests, migrating local ungulates will be at a significant disadvantage compared to resident elk feeding on irrigated alfalfa fields in the Trench. Encouraging elk to vacate that food supply and resume traditional migrations from valley bottom to the high country faces its own uphill battle.

To eat or Be Eaten

This column was published in the Cranbrook Daily Townsman Tuesday September 7, 2010.

It’s that time of year again: men wear camo, wives are lonely and elk are nervous. Yes, elk season is open, this year with a twist. Anterless elk are in the sights in some parts of the Trench, a move to try to reduce their numbers in agricultural areas and convince them to hike for the high country come spring.

Ungulate migration has long been viewed as an evolutionary strategy to avoid predators and access good forage. For most animals, life is a trade-off: eat or be eaten. You can hide as long as you want, but eventually you’ll get hungry enough to venture out to that really tasty patch of grass. Biologists have tried to answer the question “when does predation risk outweigh foraging opportunities?” to identify a trigger point for migration. The answer isn’t easy.

Mark Hebblewhite is a Canadian biologist at the University of Montana who studiesthe movement of ungulates, especially elk in the Rocky Mountains. Recent work looked for differences between overlapping migratory and non-migratory elk populations in Banff National Park and the adjacent Ya Ha Tinda winter range.

In this system, wolves (elk’s main predator) are more numerous at low elevation, so the urge to migrate was driven by an understandable desire to avoid being eaten (especially strong for soon-to-be-moms). This strategy was effective: migration lowered predation risk by 70% compared to elk who chose to stay in the valley bottom. Freed from the threat of wolf predation, migratory elk’s movement decisions were based on finding quality feed. They were successful at that too, averaging 6% better forage than their non-migratory cousins. Better food was available to resident elk, but the high predation risk kept them from accessing it.

The question then is why would any elk in the Bow Valley choose not to migrate? Why stay and run a wolf gauntlet to access poorer food? Dr. Hebblewhite and his colleagues found that human activity “effectively decouples” the forage – predation risk trade-off. By selecting areas of high human activity where wolves fear to tread, resident elk lower their predation risk from 70% to 15% higher than migratory elk. The food around human activity may not be the best, but that’s more than compensated by volume: there’s lots of it.

Are there applications for this research to the resident vs migratory elk issue here in the East Kootenay? The Banff-Ya Ha Tinda situation is different. Here, elk predators (especially wolves) are in greater numbers at higher elevations. Lower predation rates in the Trench has likely helped drive the shift over the past 20 to 30 years into separate migratory and resident or homesteader elk populations, with the latter stubbornly refusing to leave the Trench in the summer.

Add in wide swaths of tasty alfalfa forage and one wonders why any elk would leave the Trench come spring. With elk now fenced out from many of those hay fields, if the predation risk side of the equation can be shifted to again favour the high country, perhaps elk will return to their migrations.

That predation is not likely to come from four-legged animals, unless we Trench-dwelling humans suddenly decide to co-exist with wolves and other predators. Increased hunting pressure is hoped to be a predation surrogate to help encourage elk to leave. This is part of the decision by the BC government to open an anterless elk season in the Trench. The hunt is based on sound science like Dr. Hebblewhite’s that increased predation risk may convince elk that the Trench is not such a safe place after all.

A life in nature: Ian McTaggart-Cowan.

This column was published in the Cranbrook Daily Townsman Wednesday September 1, 2010.

There was a quiet passing earlier this year that marked the end of a era in Canadian and British Columbia ecology. Dr. Ian McTaggart-Cowan died April 18, 2010, just a few months shy of his 100th birthday. There has been no greater contribution to our knowledge of nature in British Columbia than Dr. McTaggart-Cowan.

His parents emigrated to North Vancouver from Scotland with him as three-year old. Rod Silver, former head of the provincial Habitat Conservation Trust Fund, has written a thorough biography of Ian McTaggart-Cowan recounting his youth spent in the Lower Mainland of the teens and twenties, exploring the forests and haunts of what was a much wilder place. 
 
There is a link to Dr. McTaggart-Cowan in almost everything we know today about birds and mammals in British Columbia. His list of accomplishments could well be unmatched in Canada: some 300 publications, definitive books on BC mammals and birds, approximately 100 graduate students (and influence on countless others who studied at UBC and elsewhere), including scientists who themselves went on to become internationally recognized experts in their field: Val Geist, Maurice Hornocker and C.S. (Buzz) Holling. Through his own work and those on whom he had direct influence, there are few areas in wildlife science today that cannot be traced directly back to Ian McTaggart-Cowan.

His awards are equally impressive: Officer of the Order of Canada, Officer of the Order of British Columbia, Fellow of the Royal Society of Canada, Leopold Medal of The Wildlife Society (the highest honour bestowed by the major international society for wildlife biologists) and others. For years, he was the honourary president of the Federation of BC Naturalists in recognition of his passion for and commitment to natural environment of this province.

The University of British Columbia was to become his second home. An undergraduate degree in 1932, followed by a brief sojourn abroad to complete his PhD at Berkley before returning home to Vancouver. His tenure took him from Professor to Department Head to Dean of Graduate Studies for the entire University.

As television emerged as a new medium in the 1950’s Ian McTaggart-Cowan was one of the first to embrace it as a means of public education. His CBC series, Fur and Feathers sought to introduce children to the wonders of nature and was followed by other television series, The Living Sea and The Web of Life.

I never had the honour of meeting Dr. McTaggart-Cowan. But I certainly knew of him. You can’t be a wildlife biologist in Canada without knowing. I recall the first time I came across one of his scientific papers as a young undergrad, deep in the depths of the University of Guelph library, far removed from the rainy west coast. I can’t remember what the paper was on, but the hyphenated name (as well as our common first name) struck me. I then soon found that for almost any topic I researched, be it bears, birds or mice, papers by the same McTaggart-Cowan would be discovered. He was the only Canadian to be so widely encountered.

There are few among us who can not only lead by example, but also inspire and raise others to levels not attainable on our own. The legacy of Ian McTaggart-Cowan, the museum collections named for him, the scholarships in his honour and numerous other awards speak of the unmatched contribution and selfless commitment of one man’s life to help us better understand the natural world, and British Columbia in particular.