Hi guys, I would like help understanding the reason for a fly infestation in my area, these flies are uncommon, they appeared a few years ago, and now they’re everywhere. Rumors that they are flies created for biological control of other species. In the image there is a sample of them, they like de…

Welcome to the forum @tobiasheitor ! I have never heard of flies being bio-engineered as control for anything. For me there are two likely scenarios for the reason behind the increase in these particular flies: Certain environmental conditions have changed recently, which have become favourable …

I suspect the second scenario is what is happening here, because most calliphorids in the Americas are invasive.

@zdanko @edanko @phycus Any idea of what fly species are those?

I would recommend posting this to the iNaturalist site for an ID.

These flies will not control pests. A few fly species, like botflies and mosquitos (male, so they cannot fertilize females), have been engineered to reduce dangerous (to humans) pest species. They tend to be ‘broadcast’ over specific areas by aircraft. Unless this is a large scale - greater than 40 …

Chrysomya sp. Introduced from Africa/Asia.

Like Even said, these are Chrysomya spp., which weren’t introduced for a specific reason. There are some species like Cochliomyia homnivorax that have, for example; that species had sterilized males introduced in the Florida Keys to stem the existing population from continuing to grow, and therefore…

Yeah, they were very likely introduced accidentally.

Unusual fly infestation

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Unusual fly infestation

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