Poecile -
Your pint 2) - If eagle owls have existed in Britain in low numbers, is it likely that we would find their fossilised remains? We find the remains of those species that have been numerous and occasionally we get lucky; finding the remains of something much more rare. For this kind of quoted information to be relevant it must have a control of some form, a comparison against a similarly rare species, do we have that? if not; to state that we have no fossil record for this species becomes almost meaningless, it is given no value, no quantification and therefore carries little validity..
yes we do have a comparative - eagles. They were formerly common across the country and were a similar top predator to EO (at probably comparative densities, having similar prey and nesting requirements). We find WTE and GE traces all over the place. They're in cave deposits, in middens, in brocks, they were a cult animal, in carvings. Their talons were used as jewelry. They're in folklore, there are old specimens of shot vagrants and wanderers and the last few wild birds in the south. Don't you find it staggering that, in the face of all that, that bronze-age to medieval people would have totally ignored EO and left absolutely nothing? No carvings, no legends, no bones, no nothing. And if EO were here naturally, then why would they be at low numbers? Even if they were, their habit of nesting in caves etc would make them even easier to find traces of, as they'd be preserved in there along with the wolves and bears and eagles.
As for Eagle Owls in pre-historic art and "ritual" art, how many times has it been found that interpretations based upon "modern" precedent and understanding has been found to be flawed as new discoveries have been made which have thrown a different light on subjects and interpretations of subjects. The chicken and the egg sometimes get "mixed up", some elements, in my experience, are pre-supposed before they are "proven" and perceived "history" is occasionally flawed as a result. How often, in Roman, pre-Roman or post-Roman art, for example, is it really possible to state with certainty: 'that's a Tawny Owl, that's a Short Eared Owl and this one here is an Eagle Owl'?..
EO are pretty distinctive, what with their tufts. We don't get confusing stories about giant tawny owls marauding livestock and carrying off chldren do we? And there's no mistaking midden/cave bones and ornamental talons. We can distinguish WTE from GE, and wolf from dog, and boar from pig. It's not that hard as, like I said, what else could a carving/painting of a large tufted owl be? LEO would hardly cut the mustard as a fireside tale...
Your point 3) - I would accept that it is most probable that the majority of UK Eagle Owls are subsequent to release, but I would most strongly refute that natural immigrants are an impossibility or even a near impossibility. I would even suggest, given our close proximity to northern mainland Europe, that the arrival such immigrants to the UK is a probability. I would therefore question a decision to the effect that The European Eagle Owl has no place in UK ecologies, simply because this is not proven..
Let's assume you're right. That they may be vagrants here. How many vagrant birds get here and breed? Think of all the Barred/Icterine/Melodious Warblers (common nearby), think of how Little Owl never colonised, or Black Woodpecker (common nearby). Think of how Snowy Owl has not colonised, or Red-footed falcon, despite all the vagrants. The numbers you're talking about are minute, and the thing about vagrants is that virtually all of them pass through and die elsewhere or re-orientate. What rare vagrants don't tend to do is breed. Yes, you can mention little egret or Med Gull, but they were common vagrants, then wintering birds. They were everywhere, turning up at all migration points and all along the coast. The basic point though, is that EO is not a 'normal' part of the ecology, in that our island ecosystem has developed without a regular eagle owl presence (because the total lack of evidence strongly points that way, before you ask, just as it strongly points that way for griffon vulture). It is therefore different from the continental ecosystem which you describe. If it was not, then we'd have black woodpecker, crested lark, beech marten, icterine warbler etc etc etc aswell, but we don't. Instead we have larger densities of woodland birds (fewer mammal predators), no black woodpecker (no wood ants), formerly large densities of water vole (no serious mammal predator), internationally important numbers of breeding waders etc etc.
I would also querie the data regarding Eagle Owl predation not for their accuracy but for the lack of comparitive quantification given in your explanation. To recognise these statistics effectively; a comparitive control must be offered, otherwise it's a case of "how long is a piece of string"....isn't it?..
how can you control for a study of diet in 5 areas? A study of no diet in 5 areas? A study of non-EO diet in 5 areas? It's the best data we have, how about that?
My point being; that to make any kind of valid assessment, a comparitive control must be introduced to the discussion.
please explain what kind of control you would find acceptable, because I'm not convinved that you understand what the term actually means.
