Title kinda says it all.
I was watching some animal rescue videos and the animals were often in bad shape due to parasites of various kinds slowly killing them. Presumably there was no underlying problem with the animal before it got infested. So, why do some animals get overwhlemed while others seem to have no problems at all? Just bad luck it walked past a bush with a lot of ticks or ate something with ringworms?
Or passed on by related animals, or curled up/mated with an infected/infested animal, or a weakened immune system or poor general health.
I cannot cite this but I’ve seen feral hogs have so many ticks and various pestilence that any other animal would be dead by lack of blood in a day. Yet, they are feisty, fast and mean as heck, still.
Seem to eat, run, mate and fight with great regularity.
Some other animals are more fragile, babies, aged and sick animals often get overloaded. And can die.
It’s wild out there.
Ringworm is a skin disease, easily transmissible by direct contact. I got it from a friend’s cat many years ago. It’s relatively harmless, unless it covers a huge portion of the body, and like other fungal infections, it can be very dangerous if a person (or animal) is immune compromised, which starvation or depletion by blood-sucking insects can also do.
I’ve seen cat rescue videos where the flea infestation was so severe, the water turned red with all that “flea dirt”, which is digested blood.
They all do, or are equally likely to. But for wild animals which are debilitated by parasites, survival rates plummet.
Where existence is “hand to mouth” and if they are not at near optimal fitness they can’t feed themselves, become prey or can’t catch sufficient prey.
Right, and if some animals have resistance to those parasites, then they’ll exhibit better survival and presumably them and their offspringi will produce more children, and so forth.
As far as the rescue videos go, I’d bet they were malnourished as part of their abuse, and that makes it all the easier for heavy infestations of flees and whatever else to take hold.
I had a little of 13 German shorthaired pointers one year. We were having a bad flea year, so every day when I came home from work, I would deflea them with malathion. 1/2 of the litter was not infested, while the other half was. Same dogs every day. I believe there is a genetic component to it.
Um… most wild animals are chock full of parasites.
People can definitely, for a number of reasons, be attractive/repellent to mosquitoes. Speaking of which, the sickle cell trait also has a protective effect against malaria, and I’m sure there are similar conditions that affect animals.
Deer ticks can weaken the animal. I have wondered why some deer avoid them and others get infested.
All the insults are cumulative.
Have ticks? You’re weakened by them and hence more prone to fleas, intestinal parasites, disease, and if a predator, starvation.
Have a hard time catching prey if a carnivore or chewing your food if a herbivore? You’re weakened due to caloric deficit and hence more prone to ticks, fleas, disease and intestinal parasites.
Have intestinal parasites? You’re more prone to ticks, fleas, disease, and starvation.
The end effect is most animals have mild cases of all those things, but a few animals really suffer down the road of exponential decay with all of them.
I think this. You only see the real sick ones. But they are sick to a degree.
As noted all wild animals are infested with parasites. Sometimes parasites so specific they only effect one specific species of animal. One mental image that stuck with me was an anecdote (might have been from David Mech) of a deer so covered with blood-sucking parasites in the winter that after it got up from a lie-down the surrounding snow was heavily-flecked with blood.
To anthropomorphize, nature doesn’t give a shit if you die of parasite-load or cancer or hoof-rot or tooth-loss by year five, if you’ve successfully reproduced (by whatever metrics) before then. Generally the older and more in physical decline an animal is, the worse the parasite load. But some can live many years with just a perpetual host of mange, fleas, ticks, liver flukes, heart worms, inimical blood protozoa, and a million other things even excluding stuff like arthritis and tooth pain. It’s probably not comfortable, but it’s a living.
It’s yet another reason why the idolization of animals “in their natural state” is a little overblown. Life free in nature sucks mightily in many ways for every creature - ‘nasty, brutish and short’
It’s not as if humans are parasite- and chronic disease-free, yet many of us survive.
All those smaller things deserve to eat and to survive just as much as the larger host critter.
Nature greatly favors quantity over quality. Sucktastic though that may be by modern human lights.
I actually brought a stray cat into the vet, and a blood test revealed flea-related anaemia that they said needed treatment, or else he was gonna die. So he did not have “little or no problem with this”, quite the opposite— on the other hand, he was not so fucked up (yet) that you would have obviously noticed.
The marine ornithology expert I heard at the New Orleans Aquarium during a penguin feeding pointed out that wild animals often hide and mask illnesses and injuries. The best and often only way to tell a sick bird is a decline in diet which is why they have have the individualized penguin feeding. Not all were equally enthusiastic about approaching the humans in the habitat but all did eat their fishies.
Unsaid but understood is that the first sign of illness for a lot of animals is sudden death.
Years ago we bought some fresh “wild caught” salmon from Costco, only to get home and see a little worm on the flesh just under the cellophane wrapping. Brought it back to the store and they refunded the purchase, but hey, they were truthful in advertising, evidently! I think if we had not seen the worm and just cooked the meat we’d be just fine, but the wife was so freaked-out by that she has refused to buy fresh salmon ever since (frozen is okay, since freezing kills the worms/eggs).
When we visited Alaska and went on a wildlife viewing day trip, we saw plenty of caribou, and some had big welts on their fur - the guide explained they were warble fly larvae and most of the animals are infected at any given time, but most are barely bothered by it unless they get a severe infection. The larvae just drop out of the animal’s skin when they mature, and the wound usually heals without issue. The guide mentioned that in times past, Inuit hunters would avoid caribou with a heavy warble load as it damages the valuable hide, so in a sense a warble infection may have been an advantage.
Wild animals you see without parasites are the ones that don’t have them yet.
I started keeping honey bees a year ago, and a question I get a lot is why I have to take care of them so much. Why not just leave them as they are in the wild? The answer is that they’ll be eaten up and die of Varroa mites in a year or so, unless they’re an Asian bee that evolved with Varroa.
That’s why you don’t really see feral honey bee colonies in North America anymore. They were mostly European bees, and they don’t survive long with untreated mite infestations. I watch mine daily, yet last October I nearly lost them to Varroa (big learning experience).
I mean, why are some humans badly afflicted by disease while others are healthy? I don’t think the situation with other species is all that different.