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Fishery Bulletin 103(1) 



Figure 1 



White marlin {Tetrapturus albidus) tagged with a Microwave Telemetry PTT-100 HR pop-up 

 satellite tag lA) and conventional streamer tag (B). 



light, and pressure (depth) measurements, and can 

 withstand pressure equivalent to a depth of 3000 m. 

 Tags programmed to disengage after five days (n = 5) 

 recorded measurements approximately every two min- 

 utes, whereas tags programmed to disengage after ten 

 days («=35) recorded measurements about every four 

 minutes. Additionally, both 5-day and 10-day tag models 

 transmitted archived and real-time surface temperature, 

 pressure, and light level readings to orbiting satellites 

 of the Argos system for 7-10 days following release from 

 the study animals. 



PSATs were attached to white marlin by an assembly 

 composed of 16 cm of 400-pound test Momoi® brand 

 (Momoi Fishing Co., Ako City, Japan) monofilament 

 fishing line attached to a large hydroscopic, surgical- 

 grade nylon intramuscular tag anchor according to the 

 method of Graves et al. (2002). Anchors were implanted 

 with 10-cm stainless steel applicators attached to 0.3-m, 

 1-m, or 2-m tagging poles (the length of the tagging pole 

 varied depending on the distance from a boat's gun- 

 whales to the water) and were inserted approximately 

 9 cm deep into an area about 10 cm posterior to the 

 origin of the dorsal fin and 5 cm ventral to the base of 

 the dorsal fin (Fig. 1). In this region, the nylon anchor 

 has an opportunity to pass through and potentially 

 interlock with pterygiophores supporting the dorsal fin 

 well above the coelomic cavity (Prince et al., 2002b; 

 Graves et al., 2002). When possible, a conventional tag 

 was also implanted posterior to the PSAT. 



Deployment 



White marlin were tagged in the offshore waters of 

 the U.S. Mid-Atlantic Bight, the Dominican Repub- 

 lic, Mexico, and Venezuela (Table 1). These locations 

 were chosen for vessel availability and seasonal concen- 

 trations of white marlin. All tagging operations were 

 conducted on private or charter recreational fishing 

 vessels targeting billfishes and tunas. White marlin 

 were caught on 20-40 lb class sportfishing tackle and 

 fought in a manner consistent with typical recreational 

 fishing practice (G. Harvey, personal commun. 2 ). The 

 first 41 white marlin caught and successfully positioned 

 boatside were tagged. Fish were not brought to the boat 

 until they were sufficiently quiet to facilitate optimal 

 tag placement. When possible, crew members positioned 

 white marlin for tagging by holding them by the bill and 

 dorsal fin in the water alongside the boat, a technique 

 often used when controlling a billfish to remove hooks. 

 On boats with high gunwhales that prohibited holding 

 the captured fish by the bill, the marlin were "leadered" 

 to the boat's side and moved into position for tagging 

 when calm. Six hooked white marlin escaped prior to 

 tagging because frayed leaders broke or hooks slipped 

 during this process. Hooks were removed when feasible; 



2 Harvey, G. 2002. Personal commun. Guy Harvey Enter- 

 prises. 4350 Oakes Rd. Suite 518. Davie, FL 33314. 



