are these active fields? Do they actually farm them? Do you know if they use pesticides? If you can find out whether they spray or not would be helpful. If they aren't active fields - like just meadows or overgrown areas that no one uses then you are probably OK.
Because grasshoppers are rather "meaty" they tend to hold toxins longer in their body than other, smaller insects. You could bring them inside and let them feed on the plants for awhile (so long as YOU don't use any bio-cides
). Wash off the plants well and just set them and the hoppers up in a tank. After a few days most toxins will have passed thru.
lele
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0.1 veiled - Luna
0.2 green anoles Jaida & Jetta
0.1 brown anole - Jamaica
0.2 house geckos - Gaia & Tia
0.2 felines - Kyndra and Líta