In Situ Tagging and Tracking of Coral Reef Fishes from the Aquarius Undersea Laboratory
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TECHNICAL NOTE In Situ Tagging and Tracking of Coral Reef Fishes from the Aquarius Undersea Laboratory AUTHORS ABSTRACT James Lindholm We surgically implanted coded-acoustic transmitters in a total of 46 coral reef fish Stellwagen Bank National Marine Sanctuary; during a saturation mission to the Aquarius Undersea Laboratory in August 2002. Current address: Pfleger Institute of Aquarius is located within the Conch Reef Research Only Area, a no-take marine re- Environmental Research serve in the northern Florida Keys National Marine Sanctuary. Over the course of 10 Sarah Fangman days, with daily bottom times of 7 hrs, saturation diving operations allowed us to col- Channel Islands National Marine Sanctuary lect, surgically tag, release, and subsequently track fishes entirely in situ. Fish were collected using baited traps deployed adjacent to the reef as well as nets manipulated Les Kaufman on the bottom by divers. Surgical implantation of acoustic transmitters was conducted Boston University Marine Program at a mobile surgical station that was moved to different sites across the reef. Each fish Steven Miller was revived from anesthetic and released as divers swam the fish about the reef. Short- National Undersea Research Center, term tracking of tagged fish was conducted by saturation divers, while long-term fish University of North Carolina at Wilmington movement was recorded by a series of acoustic receivers deployed on the seafloor. Though not designed as an explicit comparison with surface tagging operations, the benefits of working entirely in situ were apparent. INTRODUCTION he use of acoustic telemetry to track the movements of marine fishes is now a com- true with deepwater fishes that have air blad- fish with a damp towel. Each approach in- Tmonly employed method (see other papers ders (Starr et al., 2000). Thermal shock can volves a series of trade-offs that will vary this issue), producing data on fish home also result from bringing a fish to the sur- depending on the species selected for tag- ranges (Zeller, 1997; Bolden, 2001; face and then aboard a surface vessel (Kelsch ging, though most approaches involve ex- Simpfendorfer et al., 2002), habitat-specific and Shields, 1996). Each of these stressors posure of the fish to air and sunlight for some movement (Lindholm and Auster, 2003; can kill a fish outright or have sub-lethal ef- period of time during surgery. Lowe et al., 2003; Cote et al., 2004), and fects that increase the fishes’ vulnerability to Following some period of observation movement relative to the boundaries of other stressors and may preclude a fish from in a live-well on board a research vessel, marine protected areas, or MPAs (Zeller and being tagged. tagged fishes are either released directly over Russ, 1998; Meyer et al., 2000; O’Dor et Telemetry projects on fishes typically the side of the boat or are lowered to the al., 2001; Starr et al., 2001; Lowe et al., involve either the attachment of an acoustic seafloor in some form of a release device 2003). While the specific approaches to the transmitter externally (e.g., Bradbury et al., (e.g., Starr et al., 2000; Lindholm and use of acoustic telemetry vary widely depend- 1995; Lindholm and Auster, 2003; Cartamil Auster, 2003). Though the use of a release ing on the species targeted for study and the and Lowe, 2004), intragastric insertion of device can increase researcher confidence habitat in which the targeted species occurs, the transmitter down the pharynx into the that the fish has indeed returned to the sea- all projects share four common elements: 1) stomach (Bridger and Booth, 2003), or sur- floor or at the depth from which it was the collection of fishes, 2) the tagging of gical implantation of the transmitter inside collected initially, both forms of release in- fishes, 3) the release of tagged fishes, and 4) the peritoneal cavity of a fish (e.g., Zeller, volve a high measure of uncertainty. The the tracking of tagged fishes. Also common 1997; Starr et al., 2000; Bolden, 2001; pa- fate of these fish post-release is difficult to to most studies is the conduct of each of pers in this volume). Where surgical implan- determine, i.e., did the transmitter mal- these elements from the surface, where the tation is used, incisions can be closed with function, was the tagged fish consumed by extraction of fishes from their natural envi- sutures (e.g., Thoreau and Baras, 1997), sur- a predator, is the fish dead and lying on the ronment can create difficulties. gical staples (e.g., Mortensen, 1990) or an seafloor? This problem is lessened when Fishes are often collected from the sur- adhesive (e.g., Nemetz and MacMillan, data are collected indicating the tagged fish face via baited traps, long-lines, trolling and 1988). Implantation is normally conducted is moving. However, where the post-release traditional angling. Fish brought to the sur- on a padded, v-shaped surgical board (Win- data are limited or non-existent, it is often face for tagging can experience barotrauma, ter, 1996) and may involve fresh flowing impossible to know the fate of the fish with- or pressure-related stress. This is particularly seawater over a fish’s gills, or covering the out in situ observation. 68 Marine Technology Society Journal Tracking of tagged fishes is often con- Aquarius is currently located within the divers. Each trap was visited by saturation ducted manually from the surface (e.g., Conch Reef Research Only Area, a no-take divers at the beginning of a dive, with subse- Matthews, 1992; Zeller, 1997; Cartamil and reserve designated by the Florida Keys Na- quent visits depending upon the number and Lowe, 2004), recorded by acoustic receivers tional Marine Sanctuary. It provided a plat- species of fishes caught by the trap. In cases deployed on seafloor (e.g., Arendt et al., form for a 10-day saturation diving mission in which multiple fishes within a trap were 2001; Starr et al., 2001; Lindholm and in August 2002. A total of 70 hrs of bottom selected for tagging, the opening to the trap Auster, 2003), or a combination of the two time (~ 7 hr day-1) provided saturation divers was blocked and each fish was tagged sequen- approaches (e.g., Simpfendorfer et al., 2002; with sufficient time to tag and subsequently tially until the trap was empty. The trap would Lowe et al., 2003; Parsons et al., 2003). The observe 46 fish (Table 1), including black then be baited again and re-deployed. approach used to study the movement of grouper (Mycteroperca bonaci), yellowtail tagged fishes will depend heavily on the spe- snapper (Ocyurus chrysurus), princess TABLE 1 cies tagged, the region in which it was tagged, parrotfish (Scarus taeniopterus), blue List of coral reef fish species tagged at Conch Reef and the objectives of the study. parrotfish (Scarus coeruleus), and hogfish during the August 2002 Aquarius mission. Obviously, the success of acoustic telem- (Lachnolaimus maximus). We describe some Individuals etry approaches to tracking marine fishes is of the lessons learned during the mission. Species Tagged contingent on tagging fish in a manner that Yellowtail snapper 14 does not negatively affect their behavior and Mangrove snapper 2* physiology (Smolowitz and Wiley, 1998; Fish Collection Bridger and Booth, 2003). Thus any ap- Collection of fishes in situ provided us a Black grouper 1 (2*) proach that minimizes the potential stres- high degree of selectivity in the fish we chose Scamp grouper 1 sors at each step of the process is preferable. to tag. The majority of fishes were caught in Hogfish 10 In this paper we describe a study using acous- baited traps (1.5 m2) deployed at two loca- tic telemetry to track movements of coral tions on sand flats immediately adjacent to Blue parrotfish 8 reef fishes in which all aspects of the project Conch Reef during daylight hours (Figure 2). Princess parrotfish were conducted in situ from the Aquarius Both locations were sited within 300 m of Initial Phase 4 Undersea Laboratory (Figure 1). Aquarius to ensure easy access to saturation Terminal Phase 8 *These fish were tagged from the surface immediately prior to the start of the mission. FIGURE 1 Yellowtail snapper, blue and princess The Aquarius undersea laboratory (bow and starboard view) at Conch Reef in the northern Florida Keys National parrotfish, as well as black grouper were each Marine Sanctuary. Photo credit: James Lindholm caught in traps during the saturation mis- sion. The multiple yellowtail snapper cap- tured in traps appeared to be attracted to the bait (punctured cans of cat food), while the single black grouper caught in a trap appeared to be attracted more to the variety of fishes contained within the trap. Both species of parrotfishes appeared to enter the traps out of curiosity, often following con- specifics into the trap. Other species that were captured (but not tagged) included chub (Kyphosus spp.), French grunt (Haemulon flavolineatum), reef butterflyfish (Chaetodon sedentarius), gray angelfish (Pomacanthus arcuatus), blue tang (Acanthurus coeruleus), doctorfish (Acanthurus chirurgus), and green moray (Gymnothorax funebris). Our ability to capture fish in greater numbers may have been reduced by the pres- ence of large predators immediately adjacent Spring 2005 Volume 39, Number 1 69 FIGURE 2 working within a fully-protected marine re- Map of VR2 acoustic receiver array at Conch Reef, including the estimated range of detection for each receiver, serve. While collection of non-targeted fishes the boundary of the Conch Reef Research Only Area, the location of the Aquarius undersea laboratory, and the was common with the traps, all were released locations where fish were collected and released. Five meter isobaths are provided. The complete receiver array shortly after capture and with the exception (inset) is shown extending from Alligator Reef to Carysfort Reef in the northern Florida Keys.