I see many European species marked as introduced in areas where they used to occur in prehistoric or even historic times, sometimes as recently as just a few centuries ago. Is it really desirable that these organisms be marked as introduced (and by association “bad” to many people), when they have a long evolutionary history in those areas?
And when there is doubt but no scientific consensus yet about whether a species is introduced or arrived naturally, so we don’t really know one way or the other, should we mark species as introduced or native?
Could you list some examples please? Introduced status is added by users manually, so you too can change it if it’s wrong, but it’s a hard question as reintroduced specimens could be very different from those that lived thefe before.
I would say caballoid horses in the Americas are a great example. The same species Equus caballus that was accidentally reintroduced by the Europeans occurred throughout both continents until the first humans arrived. Obviously the original populations belonged to now extinct subspecies. But it does cause a weird conundrum on how one would classify them, especially when the original populations were most likely wiped out via anthropogenic mechanisms in the first place. I will admit that I tend to look at species communities from an upper-Pleistocene/early Holocene slant.
Other interesting examples could also include California condors across most of North America, black footed ferrets occurring in the Great Basin, etc.
I would not consider them an invasive species, at least no more than any of the other native herbivores. Considering the predator guilds have all been completely decimated… They are a reintroduced (albeit accidentally) species.
Keep in mind that the ecology of the americas is the same today as it was during the prior interglacials, with the exception of significant anthropogenic influence, including most of our native megafauna being extirpated…
There is a reason we need to hunt deer, bison, etc. and it isn’t because our ecosystems are healthy.
Why historic times? When we’re talking about impacts on ecosystems we’re talking about evolutionary timescales. From what I’ve seen, the admittedly small amount of research there is on these topics seems to suggest that reintroducing species that have been extinct for thousands of years is still more beneficial to ecosystems than not doing so, because the ecosystem evolved with that species present. See also functional ecology.
I agree with you, unfortunately I don’t think many here will take prehistoric data into account. Even if they really should be doing so… We have natural traps from the prior interglacial in the Great Basin with currently extant small vertebrate species comprising the majority of remains, but we will also find caballoid horses and a plethora of other extinct large mammals such as stilt-legged horses, shrub-ox, North American llamas, American camels, etc. basically we have never seen a correctly functioning NA ecosystem in historic times, but at the same time that is all we really have been able to study and most neontologists aren’t going to concern themselves with something that is outside of their ability to observe directly.
This does not mean we shouldn’t manage the horses (or any other species we might deem native) since without a completely intact ecosystem, we will obviously not have certain species interactions that could influence many things such as the population densities of prey species, the makeup of floral communities, etc. Look at when they reintroduce certain missing species to places in Africa or the wolves in Yellowstone, the other species that were there before the reintroduction will act much differently due to more dynamic interactions than before.
I kinda might be rambling here, but this topic is a very interesting one to me, coming from a paleontological background. To us anything within the last 200,000-ish years in the Americas is basically considered “modern” from an ecological standpoint.
Ecosystems clearly changed from prehistoric times, even if taxon was native back then it can be totally out of place now and it can be both good or bad, but different subspecies is very much a different taxon, so it would be nice to know European examples.
Lions are a European species that should be present in Southern Europe, but currently isn’t present.
I would agree if the species occurrence is due to habitat shifts correlating with a glacial period, ie: polar bears in Great Britain, or red foxes and wolverines being found on the floors of some Great Basin valleys. But there have been prior interglacial periods that are incredibly similar to how it is today, from an environmental standpoint at least. Last one was a bit warmer though…
This is a very complex and somewhat technical topic to delve into, especially for a more neontology oriented platform.
Those lions were taxonomically different and if you reintroduce another ssp. it will be marked as introduced, though it doesn’t mean this action would have no basis or not being “right”, this mark just shows what was brought to the place by humans.
The most obvious European example is the Fallow Deer (Dama dama). Present throughout much of Europe in previous interglacials, and even the IUCN red list - which is often frustratingly conservative when it comes to taxa that have been extinct for any period of time - considers it likely to be native to Balkan countries and Italy. Yet throughout iNaturalist it is marked as introduced pretty much everywhere.
I agree that any different subspecies from the original population should be marked as introduced. Just at the species level the taxa is “native” to the area. More semantics than anything.
Any species that has gone through the “filter” of domestication is less likely to be considered wild or reintroduced and more likely to be considered feral. Hence the debate about feral/wild horses in the Americas. We don’t have the same problem with discussing more recent extirpations and reintroductions of wildlife species that were never domesticated; examples from my state (New Mexico) include Wapiti, North American River Otter, and Black-footed Ferret. I won’t mention Gray Wolf which is always controversial.
Interestingly, the Bolson Tortoise is being gradually reintroduced experimentally as a wild species in a couple of places in my state and it hasn’t walked this area since the time when native horses did. But tortoises are less controversial than a large grazing ungulate.
I would say neither. “Unknown” is the initial default state for Establishment Means, and I think it should just be left that way in uncertain cases.
I think a more precise statement would be that the ecosystem of thousands of years ago evolved with that species present. The present ecosystem may be similar in many ways, but it is still not the same ecosystem that existed thousands of years ago. Or at least we’ll never have complete enough data to justify such an assumption.
Yes, in part because of the species that have gone extinct. That doesn’t necessarily mean it’s better, or that those species shouldn’t return. The ecology of Yellowstone was not the same since the wolves were removed, and re-introducing them changed it enormously, but most would say it made it into a more functional and healthy ecosystem.
I’m not saying we should necessarily re-introduce everything into their known prehistoric ranges, but I think it needs a much closer examination than this.
These deer now overgraze everything, that can mean that they actually do the work of exctinct bovines or that absence of wolves allow deer to grow in numbers, but they don’t “work” the way they do in Eastern populations, they don’t belong here for now and were brought by human to hunt, so they are okayish to stay as introduced imo.
The vast majority of their evolutionary history was with these species present.
Compare it to living in a country for the first 60 years of your life and then moving to another country for a couple of years. You learn the new language, sure, but you’ll never be able to speak it as well as your native tongue. I don’t think it’s unreasonable to assume that in general species do better in ecosystems that more closely resemble the ones they “grew up” in.
I think we tend to overestimate the amount organisms change in a couple thousand years.
Going from them having some detrimental effects on current, heavily imbalanced ecosystems to “they don’t belong here” is way too big a leap in my opinion. Without human pressures keeping them out they could have easily recolonized Europe (based on the fact that they do just fine here and that they did so during every previous warm period). And perhaps more importantly: in the Balkans, Greece and Italy scientists aren’t even positive that all populations are the result of introductions.