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The Biology of Sea Turtles, Vol. II
eliminated among the remaining turtles. Often, aggressive loggerheads removed for
fighting are below average in size or weight, exhibit physical scute anomalies, and
may be lighter in pigmentation (blonde loggerhead).
16.11.1.4.1 Aggressive Behavior
Fighting among juvenile loggerheads (20–48 months of age) is manifested as a
progressive escalation of aggression. An aggressive turtle will follow another turtle,
often at a distance at the bottom or below the surface. The distance soon closes, and
the pursued turtle accelerates its swimming pace to gain distance. The aggressive
turtle will accelerate to match the pursued turtle’s speed. The lead turtle will start
to circle in an attempt to elude the aggressive turtle. The aggressive turtle will bite
at the posterior carapace of the lead turtle, and will progress to biting at the rear
flippers. The pursued turtle will come to the surface in an attempt to escape the
aggressive turtle. Once at the surface, the aggressive turtle will try to bite the front
flippers and neck of the pursued turtle by coming up and over the carapace. The
pursued turtle at this point may turn to defend itself, resulting in the turtles’ facing
one another, plastron to plastron, jaws locked with heads and fore flippers out of
the water. Considerable splashing and flipper slapping on the surface accompany
the final stages of fighting. If the turtles are not separated and removed, severe injury
to both turtles will occur.
During the pursuit, incidental contact usually occurs between the two engaged
turtles and other turtles in the pens. If the aggressive turtle is not removed at the
circling phase, and fighting escalates to the surface, all the turtles in the pen, and
occasionally adjacent pens, will become agitated. Agitation advances to contact,
resulting in fighting among all turtles in the pen. Removal of all turtles from a pen
is sometimes the only remedy to an escalating fighting situation. The majority of
the time, if the aggressive turtle can be identified and removed at the circling stage,
injuries and collateral fighting can be eliminated.
16.11.1.4.2 Passive–Aggressive Behavior
Aggression in a pen can be detected indirectly. A turtle that remains at the surface,
with fore flippers folded on the carapace and head down, nervously scanning from
side to side below the surface, is a sure sign that there is an aggressive turtle in the
pen. Often, turtles in this defensive stance will not feed. Other turtles in the pen will
avoid the turtle exhibiting passive–defensive behavior and may interpret this behavior
as aggressive in itself. Early identification, removal, and isolation of aggressive and
passive–aggressive turtles is the key to pen harmony.
16.12 HEALTH PROBLEMS OF CAPTIVE-REARED
TURTLES
Although histopathological and bacteriological analytical services for sea turtle
samples are readily available (Texas Veterinary Medical Diagnostic Laboratory,
College Station, TX), it often is necessary to initiate treatment prior to receiving test
results. Sea turtles may deteriorate rapidly once a health problem is manifested. Onthe-spot diagnosis and initial treatment is often necessary to prevent an epizootic
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The Biology of Sea Turtles, Vol. II
eliminated among the remaining turtles. Often, aggressive loggerheads removed for
fighting are below average in size or weight, exhibit physical scute anomalies, and
may be lighter in pigmentation (blonde loggerhead).
16.11.1.4.1 Aggressive Behavior
Fighting among juvenile loggerheads (20–48 months of age) is manifested as a
progressive escalation of aggression. An aggressive turtle will follow another turtle,
often at a distance at the bottom or below the surface. The distance soon closes, and
the pursued turtle accelerates its swimming pace to gain distance. The aggressive
turtle will accelerate to match the pursued turtle’s speed. The lead turtle will start
to circle in an attempt to elude the aggressive turtle. The aggressive turtle will bite
at the posterior carapace of the lead turtle, and will progress to biting at the rear
flippers. The pursued turtle will come to the surface in an attempt to escape the
aggressive turtle. Once at the surface, the aggressive turtle will try to bite the front
flippers and neck of the pursued turtle by coming up and over the carapace. The
pursued turtle at this point may turn to defend itself, resulting in the turtles’ facing
one another, plastron to plastron, jaws locked with heads and fore flippers out of
the water. Considerable splashing and flipper slapping on the surface accompany
the final stages of fighting. If the turtles are not separated and removed, severe injury
to both turtles will occur.
During the pursuit, incidental contact usually occurs between the two engaged
turtles and other turtles in the pens. If the aggressive turtle is not removed at the
circling phase, and fighting escalates to the surface, all the turtles in the pen, and
occasionally adjacent pens, will become agitated. Agitation advances to contact,
resulting in fighting among all turtles in the pen. Removal of all turtles from a pen
is sometimes the only remedy to an escalating fighting situation. The majority of
the time, if the aggressive turtle can be identified and removed at the circling stage,
injuries and collateral fighting can be eliminated.
16.11.1.4.2 Passive–Aggressive Behavior
Aggression in a pen can be detected indirectly. A turtle that remains at the surface,
with fore flippers folded on the carapace and head down, nervously scanning from
side to side below the surface, is a sure sign that there is an aggressive turtle in the
pen. Often, turtles in this defensive stance will not feed. Other turtles in the pen will
avoid the turtle exhibiting passive–defensive behavior and may interpret this behavior
as aggressive in itself. Early identification, removal, and isolation of aggressive and
passive–aggressive turtles is the key to pen harmony.
16.12 HEALTH PROBLEMS OF CAPTIVE-REARED
TURTLES
Although histopathological and bacteriological analytical services for sea turtle
samples are readily available (Texas Veterinary Medical Diagnostic Laboratory,
College Station, TX), it often is necessary to initiate treatment prior to receiving test
results. Sea turtles may deteriorate rapidly once a health problem is manifested. Onthe-spot diagnosis and initial treatment is often necessary to prevent an epizootic
1123_C16 Page 434 Tuesday, November 12, 2002 8:28 AM