It's hard to condone a film that starts off with some muppet shooting pigeons for sport, but this film is so overwhelmingly stupid that it's hard not to enjoy it. Basically, it's The Birds only made by Spaniards and Italians. Which is probably why it starts with a guy shooting pigeons.
Basically, the birds are annoyed that man is damaging the Earth and are now looking for payback. Although we have countless shot of Flamingoes, Storks, seagulls etc any time there's a mass bird attack the films uses pigeons. You know, one of the least threatening birds of all. Fair enough, a couple of eagles show up to pull people's eyeballs out but it's pigeons all the way for this film.
You've got a reporter and her cameraman seemingly travelling all over the world trying to get to the bottom of all these bird attacks (and failing miserably) while interviewing people who've been attacked, like Aldo Sambrell and another guy who had an eyeball stolen by an eagle. Also the guy who was the husband of the junkie girl in the Living Dead at the Manchester Morgue is in this for about five minutes.
But what makes it so enjoyable? The bad acting, fluffed lines, the scene where the pigeons 'eavesdrop' on our heroes, the crap ending and the even crapper (but most welcome) epilogue. What about the guy having a heart attack in the middle of a bird attack? I can just imagine some Spanish racing pigeon enthusiast being bunged a couple of grand only to watch in horror as his pigeons are thrown at confused actors trying to look terrified. They probably just poured breadcrumbs all over everything too.