The biting females are a considerable pest to both humans and animals while they seek a source of blood protein to produce additional eggs:[9] greenhead larvae develop in the mud of salt marshes, and adult flies mate and lay their first group of eggs in the marsh, but to lay more eggs a female fly needs to drink an animal's blood, and so female greenheads which have laid eggs fly inland to look for prey in the area bordering the marsh; they can stay on land looking for animals to bite for up to four weeks.

[9] Their bites itch, like those of mosquitoes, but are more painful, since greenheads feed by cutting a wound in the skin with scissor-like mouth parts and sucking the blood released through it.

[12] The eggs are laid on the grass in a salt marsh; the larvae live in the intertidal mud of the salt marsh for one or two years, preying on other invertebrates, before pupating in early spring.

[9] Affected coastal communities install black box traps in marsh areas to reduce and control T. nigrovittatus populations.

This article related to members of the fly superfamily Tabanoidea is a stub.