In Situ Tagging and Tracking of Coral Reef Fishes from the Aquarius Undersea Laboratory

Abstract

We surgically implanted coded-acoustic transmitters in a total of 46 coral reef fish during a saturation mission to the Aquarius Undersea Laboratory in August 2002. Aquarius is located within the Conch Reef Research Only Area, a no-take marine reserve in the northern Florida Keys National Marine Sanctuary. Over the course of 10 days, with daily bottom times of 7 hrs, saturation diving operations allowed us to collect, 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 on the bottom by divers. Surgical implantation of acoustic transmitters was conducted at a mobile surgical station that was moved to different sites across the reef. Each fish was revived from anesthetic and released as divers swam the fish about the reef. Short-term tracking of tagged fish was conducted by saturation divers, while long-term fish 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.

The ‘pole-hooking’ method: A novel and economical technique for in situ tagging small to medium-sized fishes

“…While fishes could be caught with traps (Gitschlag, 1986;Lindholm et al, 2005), trawling nets (Tong, 1978;Sigurdsson et al, 2006), or could be hooked at greater depths and intercepted at intermediate depths to be tagged underwater (Parrish and Moffitt, 1993), the information about the origin of fish at the scale of meters would be lost. Fishes could have been attracted from longer distances by the baits' odour (particularly when traps are baited using oily fishes or other fish attractants), could have been trawled from a rather remote area, or could have been hooked by a fishing line forming a large catenary, whose effect becomes stronger with increasing depth and currents.…”

“…Due to their associated high costs, scuba diving limitations and/or expertise required, those underwater tagging methods have been applied mostly up to ∼30 m depth, and when relatively few tagged fishes are needed. The simplest procedures include the use of anaesthetics (Matthews, 1988;Matthews and Reavis, 1990) and baited traps, seine nets or mesh bags for catching fish in situ (Lindholm et al, 2005). Other diver-based methods that avoid handling fish have involved the use of tagging poles or spear-modified shafts for inserting external dart tags in the dorsal muscle of fishes (Adkison et al, 1995;Martell, 1999;Wallace, 1999; Koenig, Personal Communication 1 ).…”

Antibiotic use during the intracoelomic implantation of electronic tags into fish

“…It is unlikely that any beneficial effect is derived from such external application to an aquatic animal, as the ointments are water-soluble and quickly wash away, or the antibiotics in the ointment elute rapidly into the surrounding water. The application of an antibiotic ointment to the surface of a electronic tag just prior to inserting it into the coelom of a fish may be an alternative to sterilizing the electronic tag or an effort to treat a electronic tag that can't be sterilized because it is being implanted during underwater surgery (Lindholm et al 2005). That practice is likely both ineffective at disinfecting the electronic tag and potentially harmful by introducing a substance that the fish's body will respond to as a foreign body as it attempts to eliminate it.…”

“…Hepatic first-pass metabolism reduces the concentration of orally-delivered antibiotic delivered to the tissues (Plakas et al 1988;Björklund and Bylund 1990). Tetracycline drugs are concentrated by the liver into the bile and excreted in the urine and feces Bettoli (2005) Electronic tag coated with ointment Unknown Lindholm et al (2005), Lowe et al (2003), Holland et al (1993) Added to feed after surgery Oxytetracycline Bradford and Gurtin (2000) Added to water after surgery Nitrofurazone Carmichael (1991), Moser and Ross (1995) Oxytetracycline Butler et al (2009), Hart and Summerfelt (1975) Applied to abdomen before surgery Nitrofurazone Carr et al (2005), Carr and Whoriskey (2008) Applied to electronic tag before surgery Oxytetracycline Skilbrei et al (2009) The references cited specifically mention the use of antibiotics as part of their methods. It is not possible to identify every use of antibiotics because many publications give little or no details of the procedures used for implantation of electronic tags, often referring to one or more other publications for the methods used.…”

Coral reef research: advances through the use of SCUBA

“…This can be overcome through use of underwater habitats and saturation diving techniques (e.g. Lindholm et al, 2005), but these are expensive and limit the underwater range of the diving scientists.…”