I watched a show on Discovery Channel about re-introducing wolves to Yellowstone National Park. In it they stated that the average lifespan of a wolf was 2.5 years (IIRC). A little research shows that “average lifespan” for wolves is all over the place.
6-8 years
5-6 years
What isn’t clear to me is how this is calculated, or if these places are using similar methods. I would suspect that mortality is greatest among the very young pups, so are they included in the calculation? It would be of more interest to me to say “Infant mortality in wolves is X%. If a wolf survives the first year its average lifespan is Y years.”
Any wildlife management people here that know how it is done?
Sorry that nobody responded.
We have several significant issues with measuring lifespan.
First, the plain fact is that most creatures in the wild don’t die what we’d call a “natural” death… except as far as you naturally die from things like starvation and disease and predation. Even wolves, which are social creatures who can and do partly protect the weaker members, may not live very long compared to what biologically can. Yes, this applies to those who get past the first year of life, too.
So when you say lifespan, you’re really talking about several different things:
*Mean time per individual spent after being born and before death across the species
*Likelyhood of achieving adulthood
*Mean time spent alive if you do reach adulthood
*Modal time in years spent alive
*How long will an invidiual live if he or she was reasonably lucky
*how long could an individual live without just the right genes, avoiding cancer, and a perfect environment
So in other words, defining exactly what you mean by lifespan is a tricky number, and it’s going to depend on exactly what you mean, the environment of the creature in question (yes, identical wolves in two different regions could have very different life expectancy), and there’s s random factor based on when and how accurately you make your observations.
Or how long a rancher living adjacent to the park decides that the wolves are threatening his livestock.
I would think that your typical large dog (say a german shepherd) would have a similar lifespan, and wolves raised in captivity would live about 15 years +/-. Of course, life in the wild is much, much more precarious.
If you’re a male, for example, and past your prime in terms of protecting your pack, you’ll likely be killed by a competing male, even if you could survive for years in captivity.