Answer:
For most crops the saturation point will be reached at about 1,000–1,300 ppm under ideal circumstances. A lower level (800–1,000 ppm) is recommended for raising seedlings (tomatoes, cucumbers and peppers) as well as for lettuce production
Explanation:
(I do not take credit for the answer)
The prairie would become overpopulated and there would be no more food for the rabbits and they would eventually die.
New disease that affects the younger of a population, shortage of availability of food, new competitor for food, new predator of jaguars (though there arent many of those)
The rat. I don't know if you meant zodiac ANIMAL or astrology sign like aquaris for example. however the rat zodiac animal is defined as the weakest of all the zodiac animals.
Have a Merry Christmas,
Miri