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The main purpose of the White Wolf Sanctuary, as previously discussed, is to provide a safe, naturalistic home for arctic wolves from rescue situations. Another highly important goal of the sanctuary is to educate people about wolves and why they are important to the particular ecosystems they inhabit. Raising awareness about the plight of the wolf and the value of their conservation is a passion everyone involved in the sanctuary has to share.

An excellent example of how important wolves are to the balance of an ecosystem can be found by looking at Yellowstone National Park. Yellowstone is a national park that was established by the U. S. Congress in 1872 and spreads through parts of Wyoming, Montana and Idaho. Grey wolves were native to the park at its official identification but years of predator ‘control’ practices saw a steady decline in wolf numbers, and by 1970 it was reported by scientists that there was no longer any evidence to suggest that wolf populations were still surviving in the park.

With the absence of wolves, the top predator in the park became the coyote. Coyote, however, are unable to prey on large herbivore species such as elk, and two effects were eventually seen:

1)      The physical strength of prey species herds declined. Catching a successful kill is no easy feat for wolves, and so they naturally tend to prey on old, sick or weak members of a herd (as opposed to human hunters who tend to select the genetically prime animals; large, breeding bucks, etc.). By weaning out these weaker, older individuals, herds are left with the healthiest animals and populations are thus strengthened overall. With the loss of their top predator in Yellowstone National Park, prey species saw a marked increase in lame and sick members of their herds.

2)      Riverbed health declined. With the main predator of elk gone their herds flourished and pushed the carrying capacity of the park. No longer being chased by wolves into cover they spent a lot of time around riverbeds eating the willow and aspen trees that naturally grew in those areas. Eventually these trees were destroyed from over-feeding, thus root systems were diminished and the earth around riverbeds became unstable. Constant hoof traffic further impaired the stability of the banks. The factors of unstable earth and a decline of riverbed willow and aspen trees thus led to a decline in beaver populations because they had a lack of sustainable habitat.

Wolves were eventually reintroduced to Yellowstone National Park after a 1987 proposition where scientists hypothesised that doing so could help reduce number of elk, bison and other prey species (while also recognising that a decline in predator species such as grizzly bears and coyotes may be observed). It was an experimental reintroduction, and wolves were taken from separate packs in Canada then transported into safe enclosures created in Yellowstone just for this release.

Years later, cascade effects from this reintroduction are still being researched. The most direct effect was on prey species such as the elk – while their herd numbers are still strong, they are no longer able to as intensely feed on browse and this leaves room for other animals such as birds, insects and beaver to use the riverbed flora. With healthier riverbeds, beavers are able to build dams, fish are able to thrive and the whole ecosystem sustains itself.

This just a very quick peek into the sorts of ways returning an ecosystem to more of its native composition can restore factors of its balance. Humans seem to be obsessed with the idea of ‘managing’ populations – but species have successfully coexisted long before our managing techniques. You do see natural highs and lows of population numbers – in times of prey abundance, predators have more food available and thus their numbers will grow. This evens out, though, when the prey numbers dwindle and are not substantial enough to support the high predator numbers; when prey numbers decline so do predator numbers from an insubstantial prey source. It all balances out, naturally, through time. Without environmental tampering this is how ecosystems have survived. Evolution brings about natural change, but I look at situations like Yellowstone and see proof that such natural change and balance is enough to support ecosystems when we take ourselves out of the equation. And it does go to show that every single species has a unique niche, and when removed it truly does effect local life in ways we may not be able to anticipate ourselves or even see with our own eyes.


Sam.

http://www.whitewolfsanctuary.com

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