The behavior of individual stromateoids, other than in relation to their association with jellyfishes, is virtually unknown. Many species form schools of moderate size, as individuals are frequently captured together. The association between stromateoids (usually juvenile) and jellyfishes requires further study, but it appears to form very early in the fish's development. Stromateoids are more resistant to jellyfish toxins than other fishes. They may also associate with salps (semitransparent barrel-shaped marine invertebrate animals), where juveniles of squaretails may seek refuge. They usually hover underneath the bell of the jellyfish, but may swim in and out of its tentacles to snatch prey items (mostly zooplankton and other invertebrates). They may also feed occasionally on the tentacles and gonads of the jellyfish, and are also subjected to predation by them. Juveniles in association with jellyfishes are usually more colorful or display more complex color patterns than adults of the same species, which are usually demersal or pelagic. Individuals of some species (e.g., the barrelfish, Hyperoglyphe perciformis) may congregate under floating wreckage, oceanic flotsam, planks, buoys, or other sheltered mobile habitats. Others may gather around vessels.
Was this article helpful?