Archive for the 'biodiversity' Category

Say Good-bye to Lonesome George

Thursday, December 27th, 2012

“Whatever happens to this single animal, let him always remind us that the fate of all living things on Earth is in human hands.”

Wording on information panel beside Lonesome George’s pen

            The last member of a species died this year. “Lonesome George” was the only Pinta tortoise left in the world.

Pinta is one of the Galapagos Islands. These islands are remote from the mainland of South America, and far enough from one another so animals cannot interbreed. Separation over eons of time caused the development of distinct species on each of the islands. Perhaps the best known are finches.

HMS Beagle, on which Charles Darwin was the naturalist, made a stop on the Galapagos in 1835. A careful observer, Darwin found that there were a variety of finches on the Galapagos archipelago. Each species had its own shaped beak, and the beaks were gradated from small to large. Beak size and shape varied by diet, which in turn was determined by the niche that the bird occupied. This range in size was a clue that lead Darwin to understand evolution.

The volcanic Galapagos are about 600 miles from the mainland of Ecuador and separated by up to 50 miles of open ocean from each other. If the islands were closer together, the birds could have easily flown from one to the other and interbred, and they probably would not have developed different niches and beaks. It is only a rare storm that carries the birds from one island to the next.

The Galapagos tortoises offer another example of speciation. They are huge, the largest weighing over 800 pounds and having shells 6 feet long. They eat plants, including cacti—up to 80 pounds a day!—and can live over 100 years. They have an interesting mutualism with some finches. The birds hop on the ground facing the tortoise, at which point the giant extends its neck and rises up on its legs. The birds will then groom the reptile.

These giant tortoises are not very good swimmers, which has contributed to developing at least ten different varieties with significant differences. Whether the variations are great enough to be considered different species or just subspecies (races) is not clear.

Galapagos males assert dominance over one another by seeing who can reach his head highest. A peaked shell differentiated the Pinta Island tortoise, allowing their necks to reach higher than other varieties.

`           The meat of these animals is reportedly tasty. Sailors collected them by the thousands in the 19th Century, then turned them upside down and kept them as living larders on board ship. The tortoises could last for more than a year without food or water. This careless harvesting probably killed off some varieties and has caused confusion for biologists who are trying to figure out what species lived where.

Goats were introduced to Pinta Island in 1958. They created havoc by eating much of the food that tortoises like, further jeopardizing the reptiles. It took years to eradicate these hungry mammals.

The last known Pinta Island tortoise was found in 1971 and taken to the Charles Darwin Research Station on the Islands, where he attracted tens of thousands of visitors. Nicknamed “Lonesome George”, he was already mature so there is no way of telling how old he was.

Several expeditions combed Pinta for other members of the species. They found several skeletons but no live animal, and no sign of an animal that might have been recently alive. Lonesome George was unique.

In an effort to preserve at least part of his genetic pedigree, females of other tortoise subspecies were introduced. Unfortunately, Lonesome George never took much of a liking to them and there were no offspring. There had been thoughts of trying to preserve his lineage in other ways such as in vitro fertilization, but that wasn’t practical.

Lonesome George was found dead on June 24th. His was the 802nd known species (or subspecies) to be driven extinct in the past 500 years; almost all these extinctions have had a human cause. The government of Ecuador had made every effort to protect George’s life and preserve the Pinta species. This effort was appropriate for the first country in the world to recognize the rights of nature.

George was lucky in that he belonged to a species that was recognized as being at risk of extinction. Biologists suspect that thousands of species go extinct every year without ever being described, named or their loss even noticed.

© Richard Grossman MD, 2012

Pity the Poor Pika

Thursday, December 27th, 2012

Earlier this month I went where I had been told that there were pikas, the cold-loving relatives of rabbits, near the Wolf Creek Ski Area. I saw one little critter harvesting grasses for the winter. How much longer would this animal be able to live there before he gets roasted-out by climate change?

Even before climate change makes his rock pile too hot, my little friend will probably be rousted out by human incursion. His home is close to the proposed and hotly contested “Village” at Wolf Creek.

Wolf Creek is already suffering from climate change; bark beetles are destroying the spruces. In places, all the mature trees look dead. The only green trees are small; it will be decades before the forest is healthy again, if ever.

Billionaire “Red” McCombs’ money bought 288 acres of land just north of the ski area. For 25 years his people have been trying to make that land into a lucrative venture. They want to build a city there that would dwarf Pagosa Springs on one side of the pass and South Fork on the other. In fact, if McCombs got his way, with the “maximum density development concept” the “Village” would be almost four times the population of both those communities combined!

Let’s look at the practicalities of building a recreational city just below the most dangerous pass in Colorado. The first problem is access. There is only a single lane forest road leading from highway 160 to the parcel. The Forest Service is considering a proposal by McCombs’ people to trade some of his land for land along the highway. His stingy offer is to trade 178 acres of his land for 204 acres of public property.

The closest commercial airports are Durango and Alamosa, each about an hour and a half away with good road conditions. Stevens Field in Pagosa is closer, but doesn’t have commercial flights because it is beset by mountains and bad weather.

The infrastructure for a posh resort is also problematic. The current electric grid is not sufficient to supply the proposed resort. There are no natural gas lines up there, but apparently the plan is to truck in natural gas. Gas might be used for generating electricity as well as for heat during the subzero winter nights. It might be practical to get big trucks up there in the summer, but unreliable in the winter when most needed. Although there is adequate water, the “Village” would require a completely reliable wastewater treatment plant that can function in arctic conditions. A malfunction would pollute the headwaters of the Rio Grande River and a beautiful trout lake, Alberta Park Reservoir, below this pipedream.

Health is the most important reason I hope that the “Village” doesn’t get built. This beautiful parcel of land at 10,400 feet would be a magnet for rich people from sea level. Most of these tourists would fly in and drive rental cars directly to the “Village”. We locals are accustomed to high altitude, but many of these visitors, especially the obese and elderly, will encounter problems. Some will have to drive to lower altitudes, but a few will become acutely and critically ill. They will have to be evacuated by ambulance or helicopter, but there are times when access by either will be impossible. The closest hospital is in Pagosa Springs, over half an hour drive with good road conditions, but it doesn’t have an ICU.

Mr. McCombs must be a clever person to have gotten so rich. I am sure that he has hired a first-rate staff to look at the problems of building the “Village”. I can only surmise that they are familiar with all the problems mentioned above. Perhaps Mr. McCombs just doesn’t want to admit that it is impractical to make a resort out of his 288 acres in Mineral County.

In order to get direct access to the highway, McCombs has offered the above unequal trade. Not only does this deal seem unfair, it would also bring the “Village” a step closer to reality. The Forest Service is accepting comments on this proposal. I suggest that you learn about the possible land exchange and send your comments about the Village at Wolf Creek Access Project to: comments-rocky-mountain-rio-grande@fs.fed.us. The deadline is October first. I hope that you will agree with me that the Forest Service would be wisest to choose “NO ACTION” as the best possibility for us, for the health of possible visitors—and for my pika friend.

© Richard Grossman MD, 2012

 

Tragedy of the Commons

Sunday, March 4th, 2012

“In every deliberation, we must consider the impact on the seventh generation….”
Great Law of the Iroquois

 

            “They know that they shouldn’t fish closer than 500 meters from the coast, but I’ve seen these boats with their nets out just 200 or 300 meters offshore. The officials don’t enforce the laws.”

We were visiting the Greek island of Mykonos while on tour with the Durango Choral Society. We walked along the harbor with our guide, David, admiring the many small fishing boats. He explained facets of the failing Greek economy as well as the ancient and modern sites on this beautiful island. The Aegean Sea around Mykonos was so overfished, David said, that there were few fish left to catch.

We found proof that David was correct when we sat down to eat. Restaurants, even those overlooking the beautiful blue Aegean, had menus that listed few seafood dishes. Any seafood was prohibitively expensive since it had been caught in distant seas.

The situation that we encountered in Greece is a good illustration of the “tragedy of the commons”. That tragedy can occur when a limited resource is open to uncontrolled use by many people. Any one user may think he can benefit from taking as much of the resource as possible. This behavior is rational only in the narrow sense of self-interest. Regrettably, unbridled use of a resource is likely to lead to its depletion.

The term “commons” referred to pastureland that was available for everyone to graze his sheep in old England. Now it includes many different vital resources such as the air we breathe, the water we drink and the fish in the Aegean.

Most of us learned to share in kindergarten. Unfortunately, some adults never mastered that lesson or have forgotten it.  When there are many people using the same resource, any person who takes more than his share may deprive others of their fair share. Even worse, selfish people can deplete the resource, so eventually no one benefits from it.

In the case of fishing off Mykonos, there had been plenty of seafood for centuries. In the past the boats and fishing techniques only allowed small, sustainable catches, so the small proportion of sea life that ended up in nets was quickly replaced. Now, with more fishermen and more effective fishing techniques and many more mouths to feed, the fish supply has been exhausted. The Greek government has tried to prevent depletion by having a “no fish” zone, with poor results. People don’t seem to pay attention to the law, or the reason that it is needed.

Human population growth is one factor leading to the tragedy of the commons: more people using the same resource means less for all.

Ironically, some of the pollutants we have unintentionally added to drinking water may serve as a feedback mechanism to slow human population growth. Endocrine disruptors are chemicals that have unintended hormonal effects. They are found in much of our country’s drinking water. Some come from insecticides and other agricultural chemicals. Many plastics contain BPA, which has undesirable effects. Another source is the waste of women taking hormones. These chemicals have been shown to produce fish and other animals with sexual aberrations. It is possible that endocrine disruptors will lead to decreased human fertility.

The amount of fresh water on the planet is limited and, in some cases, is very slow to be replenished. The Ogallala aquifer is an example of a resource that is being used in an unsustainable manner. Much of the food grown in our country’s midwestern breadbasket depends on water from this aquifer. Tragically, there are some places in eastern Colorado (and in other states) that rely on the Ogallala where the water table has dropped 40 feet in just 15 years!

As our human population has grown, the apparent size of the commons has shrunk. Although the first few wells in the Ogallala made little difference to the water table, now we seem to be sucking it dry. Dumping waste into a river or the atmosphere made little difference with few people and fewer factories, but these resources have become toxic in our populous, industrialized nation. We are learning the problems that can be caused by abusing the commons.

The people who will suffer the most may be those who come after us, the “seventh generation” in the Iroquois law. Unless we think and plan ahead, our progeny will not have the use of many of the resources that we have enjoyed.

© Richard Grossman MD, 2012

Creative Commons Attribution 3.0 United States
This work is licensed under a Creative Commons Attribution 3.0 United States.