1.   They live in unsaturated habitats where harsh, unpredictable conditions keep populations from reaching full capacity.

2.   As long as the mice are moderately abundant, they will eliminate virtually all of the pupae, keeping gypsy moth populations firmly in check.

3.   Females appear to prey upon copepod eggs to keep the population in check, a study published last month in the journal Nature said.

4.   If the cormorant population was kept in check, Mrs. Gamble said, she doubted that people would hate the birds as they do.

5.   Long, savage winters kept the population in check as weaker animals -- the young and the old -- found deep snows too much for them.

6.   More immediately, Parrish said, kestrels are really good at keeping insect populations under control.

7.   Surely there are better ways than plague and genocide to keep population in check.

8.   The cats play a utilitarian role in keeping rodent populations in check, but their primary jobs appear to be that of public relations experts.

9.   The critical question was whether viruses keep the population of wild squash in check.

10.   The monkey population should be kept below the maximum number the manager has time to feed.