Hello, Rosborne: I've been on the road for a couple of weeks and have done some thinking on this matter. I haven't had a chance to read your websites yet, so that may yet change my opinion.
I think my premise that coral snake bites would always be 100% fatal to birds of prey is totally wrong. Assuming that a bird received a full dose of venom, the bird would surely die, but considering the small size of these snakes and their small mouths and fangs, it's reasonable to assume that in many cases the amount of venom delivered would be miniscule, perhaps only enough to produce localized pain and partial paralysis. I think that in a population of hawks living in an area with a viable population of coral snake every hawk would have multiple encounters with these snakes until the hawk either receives a fatal bite or a temporarily disabling bite. That hawks have such keen sight and fly high and cover large territories, encounters are very likely considering the brightly-colored snakes.
It's always possible that the birds are genetically programmed to avoid the color red in response to the early coral snakes venom evolution, but this process would have to have happened in every species of hawk and eagle etc., and this seems way to complicated. I think the learning experience is more likely.
I've always found it difficult to imagine what the world had been like before the arrival of man, especially technological man, and the effect we've had on the natural world. Ecological niches would have in balance and saturated with the resident species. A case in point is the greatly reduced numbers of snakes in the wild.
