Category Archives: Bio-Diversity

Opinions about bio-diversity and its importance to life on the planet

Sky Islands

There are many sky islands in Arizona.  Madera Canyon was one of them. Madera Canyon is located on a sky island. We went there after the debacle of Tucson’s Festival of Books. Sky islands are  incredible mountain ranges that rose up abruptly out of the desert lowlands without  foothills.  The mountains seemed to be  emerging out of the earth as if by magic.

Later I learned more about this phenomenon.  I learned that such mountains usually had an elevation of between 6,000 and 8,000 feet. I also learned that these mountains which looked like islands in a sea of grass or sea of desert scrub actually had an abundance of wild life.  These islands include most of Arizona’s biotic communities. They are among the most bio-diverse ecosystems on the planet. They are often the meeting place between desert and forest and everything in between. It is precisely that diversity that attracts wild life, especially birds. That is why these sky islands contain well over half the bird species in all of North America.  Not just Arizona. They also contain 29 bat species, more than 3,000 species of plants, and 104 species of mammals.


Sky Islands are havens of biodiversity. That is really their most important feature.  When you move into these “islands” in the desert there is an astounding range of biodiversity.  As Gary Paul Nabhan said, “In fact the “sky islands” of southeastern Arizona and adjacent Sonora are now recognized by the national Union for the Conservation of Nature as one of the great centers of plant diversity north of the tropics.”

The reason for that diversity is of course the great variety of topography in the state. That produces a wonderful variety of life, both flora and fauna. As Nabhan said, “When we compare our desert with others, the contrast is striking. Overall, the Sonoran Desert has the greatest diversity of plant growth forms–architectural strategies for dealing with heat and drought–of any desert in the world.”

The Sonoran Desert is certainly not the bleak and barren place that many expect–and sky islands are the apexes of diversity.

What makes Madera Canyon so special is the creek at the bottom. It traverses  4 life zones and many habitats between the desert floor and the mountain tops.  It has become world famous for its diverse flora and fauna. According to the Friends of Madera Canyon, “the variety of climates within 10 miles is similar to that found in driving from Arizona to Canada!

Southwestern Arizona and this canyon are spectacular places for people who love wildlife and wild plants. This area is ranked the third best birding area in the US!  It contains some 400 birds species and especially 14 of Arizona’s 15 hummingbird species. That is more hummingbirds than any where else in the United States. But today we saw none at all.

It was interesting that the more we gained in altitude the more deciduous trees appeared and the less cactuses.   I have learned that usually in Arizona the higher the altitude the higher the precipitation so the more diverse the vegetation. Trees need the added the moisture on the higher elevations. Of course, if the mountain is too high, as in the San Francisco Peaks then there are no trees at all. Just snow. Trees, like all life is finicky.  Like Goldilocks, things have to be just right.

The landscape of southern Arizona seems dry—it is dry.  But it does get rain. In fact this region gets about 11 inches (280 mm) of rain per years. This is enough rain to allow a surprising amount of vegetation to flourish. Even wild flowers abound.  That seems impossible. It looks so dry and nearly barren. But the land is not barren—far from it.

On the day we were there an enthusiastic birder showed me a photograph of an Elegant Trogon (Trogon elegans) one of the rarest birds in the United States. A couple of years ago my brother-in-law Harv and I went in search of it but did not find. He has seen it a few times. Me never. Darn! The birder showed me a photograph he had taken of it. I was really jealous.  Later I went in search of it. I found another birder who had found it and he told me exactly where to go, but I missed it. I am an incompetent fledgling birder.    We spent some time sitting on a bench with camera and binoculars in hand. We saw a lot of birds of different species, but surprisingly no hummingbirds. Usually in the past we saw a large variety of hummingbirds here. I was puzzled by their absence.

House Finches are interesting birds because they were released in the eastern part of North America by people who brought them from Europe in the 1940s and now they have spread over most of North America including Arizona and Manitoba.


Acorn Woodpeckers often drill small holes in trees in the autumn to insert their acorns. Often their “granary trees” are used over and over again and contain thousands of acorns. Aren’t birds weird?

Mexican jays have co-operative breeding where the young from previous years help the parents to raise the new young.  Nature is not just competition, sometimes it involves cooperation.


Species that love us


Professor Pearson said that although humans have caused incredible damage on wild life, not all species are in decline. Why is that? Dr. Pearson finds this important. So do I. The fact is that  some species have adapted to life on a planet dominated by one species, Homo sapiens. They seem to like us! Can we learn something from the adaptable species?

Pearson said that scientists have learned that some species in urban environments have experienced accelerated evolution. For example, cockroaches and pigeons have changed their behaviors to live and even thrive in urban environments. How did that happen?

Scientists have been studying a species I am very familiar with. It is called Crepis setosa, or Hawksbeard. It was originally brought over to North America by Europeans and now is common all over North America including Manitoba. Scientists have learned a very surprising thing about this common plant, namely, that it has evolved its method of propagating seeds. Instead of sending them in the wind it is now tending to drop the seeds to the ground instead. What is remarkable about this evolution is that it has happened in 15 years! That is an astonishing rate of evolution.

Coyotes in cities have also been evolving to live alongside humans. As a result coyotes have learned to hunt deer in packs, they are less shy, larger, have different teeth, and have larger territories than they did a short time ago. Again they adapted and then evolved in very short periods of time. That is why coyotes can now be found in nearly every major city of North America. I have seen them in Vancouver.

European Blackbirds have first adapted and then evolved to sing louder songs. They have done that of course to compete with noises humans have brought to cities.


30 years ago Anna’s Hummingbirds did not fly to Arizona. At least they were very rare. Now they are common. At this time of year where we live they are the most common hummingbirds. Why is that? Do they love the feeders that humans put out all over? Has the climate changed enough to attract them? Now these hummingbirds have found that they likelife in the city. People plant flowers all over the place just for them. So it must seem. The heat island effect of cities is also likely attractive to Hummingbirds. They seem to like cities, and who can blame them? Maybe they even like us!

Neo-tropic cormorants are not common to the Phoenix area, but there were virtually none here 15 years ago. Things have changed enough that these birds have learned to adapt to the city, even though they must share it with about 5 million other people. Now these cormorants are common.

These are examples of species that are managing to adapt to live and even thrive with humans. Can more species do this? Are there things humans can do to make adaptations by other species easier? These are all questions that Professor Pearson raised.

The problems of species decline are massive. We will need more knowledge. Knowledge is more important than money. Though it costs money too. We will have to work together, collaborate, to get more knowledge. All of that knowledge, experience, and wisdom will have to be shared so that we can attack the problems ahead.

Further changes in the urban ecosystem can be expected. Change is the only constant. Social, economic, and cultural changes are all important. Their impacts will be important. The continuing rise of the numbers in the middle class will have a major impact on the world. As the numbers of the middle class rise, their impact on the environment will grow exponentially. There will be greater consumption, more cars, greater waste, increased pollution, expanding extraction of resources, and always, more degradation of the environment as a consequence. This is what we can look forward to if we’re lucky!

Yet again there will be positives too. It won’t be all bad. We can expect people to have fewer children and that will mitigate environmental impacts. Education will improve and that will improve the lives of millions. People will have more free time. People will have more hobbies. All of this will bring about more citizen science. It is a sad fact that there is not enough money, even in the richest country in the world, to fund all the research that is needed. Pearson believes, citizen science will help reduce the harmful effects of this omission.

Of course people must learn to do more than play with their phones, iPads or watch their various monitors. People will have to learn to enjoy learning. Private citizens who become bird watchers are good examples of the new citizens that will be needed. Scientists will use these people to help them do science. The professional amateur will be a boon to society. More and more researchers will look to them for help in many disciplines.

Scientists will have to learn to collaborate more, use social interaction to a greater extent. A good example is how Scientists will learn to use crowd sourcing to a greater extent. Many use it already. If a scientist puts a question ‘out there,’ it is amazing how many responses the scientist will get and how many creative solutions or proposals. Businesses will learn to do this too. A business has a problem, it asks the world to comment, suggest, and help. This will become much more common. Perhaps the best solutions will be rewarded.

All of this can help to create a new ecology, including urban ecology. That does not mean the Grand Canyon won’t be important any more. It does mean we won’t be able to rely solely on such iconic places. The urban landscape might become more important than the Grand Canyon from a conservation perspective.

The key question will be: how do we work with nature manage and control the new world that is rapidly approaching? It will be vitally important for us to learn to adapt. Species will be lost. What can we do to minimize the losses while fostering the gains?          What will be the future of biodiversity in the cities in 2090? Will we recognize them? We will need big parks in the city. Parks like Central Park in New York City, or Hyde Park in London, or Assiniboine Park in Winnipeg. Politicians a century ago had foresight. Those parks were very expensive but those leaders found the will and the money to do such great projects. We will need such forward thinking from our current crop of political leaders.

Things won’t be easy, but we have a chance. We must take that chance with eyes and minds both wide open.

The Lorax


My granddaughters, Emma and Nasya came over for the night. It was a sleepover. They wanted to play in the hot tub, play pool, and watch a movie. We did all of that. I offered to watch a movie with them, intending to read as they watched, but they tricked me. Nasya insisted that we keep the lights out so she could watch it better. But I tricked her; I watched the movie they had chosen and loved it. That was much to my surprise.

The movie we watched is called The Lorax. It is an animated film based on a story by Dr. Seuss. The forest dwelling Lorax wants to save the shortsighted Once-ler who is trying to get rich by cutting down every tree in the forest. He replaces the trees with fake trees that he thinks are better and that help him make a profit.

Once-ler, being a good capitalist, tried to make as much profit as he can so he tried to sell Theneeds. I think the reference is to needs. He manufactures needs. He induces people to want what he can sell. Is that not capitalism at its finest?

Of course, that leads to environmental degradation as air quality deteriorates and there is nothing left to create more air. Yet the people can’t stop until they have cut down the last real tree.

The Once-ler also considers putting air in a plastic container to sell to the people who no longer have clean air to breathe. A critic asks, “Do you think people will be stupid enough to pay for air in a plastic bottle when they can get it for free?” The answer, of course, is obvious, that is exactly what people do with water isn’t it? They certainly are stupid enough.

I was surprised to see how seriously Emma took to the film. She had a very hard time when the trees were cut down. I tried to reassure that things would get better. And they did. As in most kids’ movies, good triumphed in the end. “Thank goodness for good.” That was another line from the movie. Perhaps it was the theme.

Throughout the film, outside the home of the Lorax, is a rock labelled “Unless.” At the end we learn this is from a quotation by Dr. Seuss. “Unless someone like you cares an awful lot, nothing is going to get better.” That should be the motto for the environmental movement.

I hope my grand daughters learned something today. I think they did. I know I did.