Analysis of Sharksucker, Echeneis naucrates, Induced Behavior Patterns in the Blacktip Shark, Carcharhinus limbatus

Abstract

I analyzed and quantified the behavior of blacktip sharks, Carcharhinus limbatus, irritated by sharksuckers, Echeneis naucrates, attached to their bodies. The sharksucker induced behavior patterns were divided into simple rotational patterns, expressed by body turns along their main axes (roll, yaw, pitch); and complex patterns (wiggle, shake, wind, chafe), consisting of a combination or a repetition of simple behavior patterns. Three nonrotational behavior patterns were also observed (freeze, yawn, flicker). Of the 78 blacktip sharks examined, 70 performed either a simple or a complex pattern, or a combination of the two types. Of the total 195 rotational behavior patterns observed, only three wind patterns, performed as chaffing, led to the dislocation of a sharksucker, implying that the shark's primary intention may not be to shake off the teleost, but to initiate a position change to a less sensitive part of its body. Three sharks showed behavior patterns resembling typical agonistic display patterns, but they were induced by sharksuckers, not triggered by the presence of humans.