Transintestinal Expulsion of Surgically Implanted Dummy Transmitters by Bluefin Trevally—Implications for Long‐Term Movement Studies

Abstract

The feasibility of long‐term acoustic monitoring of coral reef fish movements was evaluated by quantifying transmitter retention times for captive bluefin trevally Caranx melampygus and detection patterns of transmitter‐implanted free‐ranging bluefin trevally. Wax‐coated dummy transmitters (9 × 22 mm; 3.6 g) were surgically implanted into the gut cavity of four captive bluefin trevally. The fish retained the dummy transmitters for 17–22 months, but at the end of the study transintestinal expulsion was in progress in one individual. Five bluefin trevally captured at Honokohau, Hawaii, were surgically implanted with long‐life (1‐year) coded transmitters and released. Their movements were monitored with the use of 27 underwater receivers deployed along a 115‐km stretch of coastline. The five bluefin trevally were detected by the receivers over periods ranging from 1 to 173 d (mean, 60 d), and their movements spanned up to 10.2 km of coastline. Daily movements were consistent with those observed by previous short‐term active tracking studies and consisted of crepuscular migrations of 1–2 km between separate daytime and nighttime habitats. These data suggest that passive monitoring of bluefin trevally movements for periods of up to 22 months is theoretically possible and that transmitter expulsion is not necessarily the cause of shorter detection periods.

Seasonal and diel movements of giant trevally Caranx ignobilis at remote Hawaiian atolls: implications for the design of Marine Protected Areas

“…Over our 5 to 12 mo monitoring period, giant trevally frequently moved back and forth over distances of up to 5 km, and periodically ranged across entire atolls, with minimum distances of 10 to 29 km. The regular movements of other previously-studied coral reef fishes are on a much smaller scale, ranging from a few meters up to a few kilometers (Ogden & Buckman 1973, Holland et al 1993, Holland et al 1996, Zeller 1997, Righton et al 1998, Meyer et al 2000, Meyer 2003, Meyer & Holland 2005, Meyer & Honebrink 2005.…”

“…We brought captured giant trevally alongside the skiff, where we tail-roped and inverted them to initiate tonic immobility. Giant trevally remained docile in this position while we surgically implanted transmitters into the body cavities of each fish through a small incision in the abdominal wall (Meyer & Honebrink 2005). Following transmitter insertion we closed the incision with interrupted sutures, removed the hook and released the fish.…”

“…The entire handling process took less than 10 min and all giant trevally swam away vigorously on release. Prior captive experiments using a similar surgical implantation protocol on closely related bluefin trevally Caranx melampygus resulted in 100% survival (Meyer & Honebrink 2005).…”

“…Despite this basic design requirement and the burgeoning popularity of MPAs as coral reef management tools, empirical data quantifying long-term movement patterns and space requirements of coral reef fishes remain scarce (Roberts & Polunin 1993, Kramer & Chapman 1999, Nowlis & Roberts 1999, Sadovy et al 2003, Gerber et al 2005, Meyer & Holland 2005. This is of particular concern given that most existing MPAs are relatively small (74% <10 km 2 , Halpern 2003) yet coral reef top predators are potentially wide-ranging (Sadovy et al 2003, Meyer & Honebrink 2005, Lowe et al 2006.…”

Movement patterns and home ranges of a pelagic carangid fish, Caranx crysos, around a petroleum platform complex

“…Fish were collected using lures with barbless hooks in order to minimize physical trauma. Intraperitoneal implantation of acoustic tags followed the method of Meyer & Honebrink (2005), though tissue adhesive was not used. Following surgery each fish was placed in a holding tank containing oxygenated seawater until the fish recovered equilibrium.…”