mmm it could be several things
1) They could be all of the same species. Some spp have a high variability.
But if they are separated by coulors
??
2) It could be 2 diferent species and one prefer bush A and the other the bush B
But if both bushes are from the same species??
3) It could be the microclime in both bushes: Maybe one is cooler than the other and snails are there in fonction of preferences.
4) Maybe it is the competition between species. The stronger snails will be on the bush they prefers and leave the other on the other bush.
Do you have any other idea??
