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How do weever fishes defend themselves?

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Bluefin tuna swimming underwater in a group, with silvery bodies and streamlined shapes, near Japan. — perciform Bluefin tuna (*Thunnus thynnus orientalis*) in the waters near Japan.

Weever fishes (family Trachinidae) defend themselves using a specialized venom apparatus that can inflict extremely painful wounds on potential threats, including humans who may step on them in shallow waters.12

Their defensive mechanism consists of two primary components:
* Dorsal Spines: The first dorsal fin is supported by sharp, spiny rays that are associated with venom glands. These spines feature a grooved structure designed to deliver venom.132
* Opercular Stinger: There is a sharp, venomous spine located on each gill cover (the opercular structure).12

When threatened or stepped on, these fishes can use these structures to inject venom, causing immediate and intense pain, swelling, and other severe symptoms. It is important to treat these animals with caution, as their defensive capabilities are highly effective and can cause significant distress to those who encounter them.24