I've created a world where science has developed a new species of bird (kind of a bird, it's like a Basset Hound with wings) to be used purely as a utilitarian species. (Carrying of small loads, messages, etc.)
To set the, well, setting (in brief): in the year 2015 a (very advanced) company engineered the first of this species, and it was a huge success. They engineered a few more of them and the species started reproducing. The original birds were a huge success: they were vegetarian, they ate very little of what they did eat (mostly grass), they were completely trainable, and they could fly anywhere from ground level to 20,000 ft in the atmosphere. This makes them very convenient for long-distance hauls.
The problem, was that within ten years the population had started growing out of control, and the birds evolved to be carnivorous. They retained their original design, however, and are still completely docile, to humans. Unfortunately these birds are capable of eating small dogs and cats now, and pose a huge threat to small wildlife. (They're more aggressive than hawks, and in much more populous.) They eat all sorts of meat now: other birds, small pets, squirrels, you should get the picture by now.
The science community did not foresee this event when they created these creatures, and have no easy way of removing them. Evolutionary manipulation is out of the question.
So, the question is, how do we create a mass-extinction of these creatures?
My first thought is: the science company created this toxin that is capable of killing these Basset-birds (for lack of a better term), and it's very effective. The problem is now distribution. (How the hell do we get this toxin distributed across the entire earth, from 0 ft of elevation, to 20,000 ft of elevation?
I have no second thought on the idea, I just haven't had the creative spark to create a way to kill them all.
A couple notes:
- The current year is 2025. The science community would like an action to eliminate them as quickly as possible. Ideally, in the period of less than a year.
- Science is not "magically evolved" or advanced. This one company is, but that's because they only poach the best and brightest (and have all the government/military contracts in the United States, as well as Israel and England).
- These birds are fast. Really, really fast. They can fly in excess of 80 mph, which makes them great for delivering and hauling small things. They do, however, lack maneuverability. They can't turn to save their lives.
- These birds are distributed across the entire world. There is not a continent, or country, (apart from Antarctica) that doesn't have them. They are all-weather capable.
- I forgot to mention this, but a comment brought it up: these birds evolve quickly. Very quickly. Any toxin would have to target all of them at once.
So, back to the question: how could these birds be eliminated, period?