Growing up, I was aware of DDT, and the fact that it led to great health issues across the nation. However, I was never aware of the fact that one seemingly insignificant (for lack of a better word) species can alter the ecosystem so greatly. When listening to/ watching what had happened to the wolves in Yellowstone, it opened my eyes to the fact that everything, especially organisms, exists for a reason.
In the beginning of the 20th century, wolves were seen as pests and vicious predators which led to a Government sponsored extermination campaign. In a way, the wolves being hunted purely for being “vicious” is somewhat similar to DDT being used just for the fact that some insects essentially… existed. Besides the fact that these wolves were completely eliminated from the park over 70 years ago, having them brought back into Yellowstone was quite groundbreaking. Starting in 1995, 41 grey wolves were returned to the park over a span of two years, and since then their numbers have increased steadily. The hunting of both Bison and Elk (nearly 2,000 a year) by the wolves allowed others, such as hundreds of species of beetles, to flourish and expand in population. Had the wolves not re-entered the ecosystem of Yellowstone, many species would have died out in that particular habitat, due to the food chain overpopulating. In the 1980s, the Elk and Bison population “exploded”, as there was no predator to keep the numbers down. What Yellowstone was truly missing in the absence of the grey wolves was its trophic cascade, which doesn’t seem all that important to us, when in reality we live in a trophic cascade of our own.. A trophic cascade is defined as an ecological phenomenon triggered by the addition or removal of top predators and involving reciprocal changes in the relative populations of predator and prey through a food chain, which often results in dramatic changes in ecosystem structure and nutrient cycling. Perhaps the best example shown in the segment was the population increase of plant life, in particular the Willows.
Willows in Yellowstone have grown immensely within the past ten years, as the Elk have fallen back into their fight or flight habits when being hunted, rather than eating all hours of the day. Since the flush in growth, rare and critical habitats have been created for songbirds, as well as creating a well stocked supply of food for beavers. Willow plants are a key food for beavers, and in their ability to eat and obtain more of it, the beaver population of Yellowstone went from 6 without the grey wolves, to now more than 90 with the wolves being back in the ecosystem. With the dams and lodges being built from the increasing beaver population, the creek was dammed with a lodge in order to create a pond. Since the creation of said pond, creatures that live and thrive in water habitats (such as fish, birds, amphibians, moose, small otter, and mink) have come to populate the park further, resulting in a fully intact ecosystem to reflect the world as it should be.
The story of the grey wolves in Yellowstone should serve as a severe warning to everyone, including those of us who don’t find much interest in it. This has been known as one of the greatest conservation success stories, and seeing the effects on how carnivores structure the ecosystem is quite important. God forbid we let out world keep going further like this, we may be the next grey wolf extermination project.
It is interesting how you mention that we could be the next gray wolf extermination project. I have never thought of it in that way but it is a real concern. We should take it into consideration and be more careful as a species.
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