Jack mackerel Trachurus japonicus juveniles use jellyfish for predator avoidance and as a prey collector
Article first published online: 31 MAR 2008
© 2008 Japanese Society of Fisheries Science
Volume 74, Issue 2, pages 276–284, April 2008
How to Cite
MASUDA, R., YAMASHITA, Y. and MATSUYAMA, M. (2008), Jack mackerel Trachurus japonicus juveniles use jellyfish for predator avoidance and as a prey collector. Fisheries Science, 74: 276–284. doi: 10.1111/j.1444-2906.2008.01522.x
- Issue published online: 31 MAR 2008
- Article first published online: 31 MAR 2008
- Received 21 June 2007. Accepted 9 October 2007.
- Aurelia aurita;
- behavioral ontogeny;
- commensal behavior;
- Nemopilema nomurai;
- Trachurus japonicus
ABSTRACT: Juveniles of carangid fishes including jack mackerel Trachurus japonicus are known to associate with jellyfishes. The function of this association behavior was studied through rearing experiments and underwater visual observations. Association behavior of jack mackerel with moon jellyfish in experimental tanks was more frequent in the presence compared to the absence of predators (chub mackerel Scomber japonicus). In the experimental tanks, the presence of jellyfish, however, did not mitigate predation by these predators. Although jack mackerel did not feed on the jellyfish itself, they frequently fed on the captured prey (Artemia nauplii) whilst in the gut cavity of the jellyfish. Underwater observations of giant jellyfish Nemopilema nomurai off Kyoto and Fukui prefectures revealed that approximately 30% of these jellyfish were accompanied by jack mackerel juveniles with body sizes ranging 10–45 mm standard length (SL). Considering that jack mackerel juveniles found in subtidal rocky reefs ranged 40–120 mm SL, we considered that jack mackerel from 10 to 45 mm SL associate with jellyfish as a hiding place as well as a food collector, until they find a suitable reef habitat when they attain approximately 40 mm SL.