Sea Turtle Husbandry
431
16.11.1 SEMIWILD CONDITIONING
Prior to use in research projects and before release, NMFS STF loggerhead sea
turtles are given a period of semiwild conditioning. Conditioning introduces the
turtles to a wild-type environment while keeping them in a controlled and observable
space. Kemp’s ridleys that are regularly exercised exhibit greater strength and stamina than turtles that are not exercised (Stabenau et al., 1992). Both loggerhead and
Kemp’s ridleys that are semiwild conditioned for a period of 2–4 weeks appear to
have increased strength and stamina compared to unconditioned turtles (J. Mitchell,
personal communication).
16.11.1.1 Conditioning–Rearing Pens
Large pens have been constructed at the NMFSPC facility to accommodate up to
200 sea turtles that are 2 years old. The pens range in size from 92 to 223 m 2 and
0.76 to 2.1 m deep. The pens are framed with treated wooden pilings and metal pipe
covered with either vinyl-coated metal wire mesh or plastic Durethene ® (ADPI,
Philadelphia, PA) mesh. The pens are lined on the inside bottom perimeter with a
skirt of vinyl-coated metal wire to keep the turtles from burrowing under the pen
walls (Figure 16.5). Various walkways, bulkheads, and docks provide access to the
pens. The pens contain a natural bay bottom, including sand, seagrass, shell rubble,
and rock. The bulkhead walls and mesh sides contain a variety of biota, including
algae, barnacles, oysters, sponges, soft corals, tunicates, and various species of
cnidarians, echinoderms, fish, crabs, shrimp, and mollusks.
After transportation, the turtles are given a 24-h acclimation period prior to
introduction into the pens. A series of independent basins equipped with a flowthrough seawater system is used for acclimation, for holding aggressive turtles, and
for treatment/observation of problem turtles. The basin system consists of plastic
laundry tubs in groups of 10–21 connected to a common drain with water level
maintained by an adjustable standpipe. Seawater is delivered by submersible (0.5
hp) pumps feeding an incoming line of valves. Each incoming water valve supplies
water to two basins at a variable rate of 150–227 l/h. The basins are housed in a
structure shading them from direct sunlight (Figure 16.6).
16.11.1.2 Temporary Holding Facilities
Unfiltered flow-through seawater systems should be avoided. Larvae in the water
will settle in and on the pipes, rearing containers or tanks, and sea turtles. At
NMFSPC, barnacle larvae settle on the carapace, plastron, and skin of the loggerheads in unfiltered flow-through seawater systems. This problem is confined to the
holding tanks and is rarely observed on turtles in the pens. Although epibiota are
common to wild loggerheads (Frick et al., 2000), turtles maintained in confined
spaces are susceptible to rapid fouling. Rapid turtle growth is common during
conditioning. As turtles grow, new carapace tissue is laid down between the scutes
(suture lines). This new tissue is easily distinguished by color, and is often accompanied by an attractive striated pattern. Barnacles settling on this new tissue are able
to penetrate deeper than on older tissue, and with heavy infestation will lift the edges
1123_C16 Page 431 Tuesday, November 12, 2002 8:28 AM
431
16.11.1 SEMIWILD CONDITIONING
Prior to use in research projects and before release, NMFS STF loggerhead sea
turtles are given a period of semiwild conditioning. Conditioning introduces the
turtles to a wild-type environment while keeping them in a controlled and observable
space. Kemp’s ridleys that are regularly exercised exhibit greater strength and stamina than turtles that are not exercised (Stabenau et al., 1992). Both loggerhead and
Kemp’s ridleys that are semiwild conditioned for a period of 2–4 weeks appear to
have increased strength and stamina compared to unconditioned turtles (J. Mitchell,
personal communication).
16.11.1.1 Conditioning–Rearing Pens
Large pens have been constructed at the NMFSPC facility to accommodate up to
200 sea turtles that are 2 years old. The pens range in size from 92 to 223 m 2 and
0.76 to 2.1 m deep. The pens are framed with treated wooden pilings and metal pipe
covered with either vinyl-coated metal wire mesh or plastic Durethene ® (ADPI,
Philadelphia, PA) mesh. The pens are lined on the inside bottom perimeter with a
skirt of vinyl-coated metal wire to keep the turtles from burrowing under the pen
walls (Figure 16.5). Various walkways, bulkheads, and docks provide access to the
pens. The pens contain a natural bay bottom, including sand, seagrass, shell rubble,
and rock. The bulkhead walls and mesh sides contain a variety of biota, including
algae, barnacles, oysters, sponges, soft corals, tunicates, and various species of
cnidarians, echinoderms, fish, crabs, shrimp, and mollusks.
After transportation, the turtles are given a 24-h acclimation period prior to
introduction into the pens. A series of independent basins equipped with a flowthrough seawater system is used for acclimation, for holding aggressive turtles, and
for treatment/observation of problem turtles. The basin system consists of plastic
laundry tubs in groups of 10–21 connected to a common drain with water level
maintained by an adjustable standpipe. Seawater is delivered by submersible (0.5
hp) pumps feeding an incoming line of valves. Each incoming water valve supplies
water to two basins at a variable rate of 150–227 l/h. The basins are housed in a
structure shading them from direct sunlight (Figure 16.6).
16.11.1.2 Temporary Holding Facilities
Unfiltered flow-through seawater systems should be avoided. Larvae in the water
will settle in and on the pipes, rearing containers or tanks, and sea turtles. At
NMFSPC, barnacle larvae settle on the carapace, plastron, and skin of the loggerheads in unfiltered flow-through seawater systems. This problem is confined to the
holding tanks and is rarely observed on turtles in the pens. Although epibiota are
common to wild loggerheads (Frick et al., 2000), turtles maintained in confined
spaces are susceptible to rapid fouling. Rapid turtle growth is common during
conditioning. As turtles grow, new carapace tissue is laid down between the scutes
(suture lines). This new tissue is easily distinguished by color, and is often accompanied by an attractive striated pattern. Barnacles settling on this new tissue are able
to penetrate deeper than on older tissue, and with heavy infestation will lift the edges
1123_C16 Page 431 Tuesday, November 12, 2002 8:28 AM