There never were snakes in Ireland in Historic Times.
The glaciers wiped them out.
They introduced wolves to the Pacific Northwest, where in some sections they wiped out local deer.
THEN, since they still had to EAT, they started moving closer to towns and taking pets.
And, since they do tend to have offspring, they INCREASE in numbers, so that now in some areas they move in PACKS.
How long before a child is taken from some farm? An attack by a PACK of wolves is unstoppable until you are toting
a semi-automatic at all times.
And even then—with one wolf going for each limb, and another for your throat, and two more coming from behind—
you still may not make it.
Yeah, re-introduce the wolves...
I'm not disputing this --- I don't know enough about such things to dispute --- but there was a window of time (roughly 10,000 - 7,000 BC) as the ice was retreating when there was a land bridge connecting the south-eastern tip of Ireland with south-western England, and connecting also England to the continent of Europe. Supposedly humans crossed the land bridge from Britain to Ireland in about 7,000 BC; then the rising sea level flooded the land bridges and, voila, the British Isles.
So why would there be snakes in Britain but not in Ireland, when the snakes had a couple of thousand years to complete this migration before the lowlands were flooded?