426
The Biology of Sea Turtles, Vol. II
16.6.6 FEEDING PROBLEMS
Overfeeding of loggerheads and Kemp’s ridleys with commercially prepared diets
can cause buoyancy problems (bloating–floating). Bloating can be chronic, resulting in carapace–plastron deformities, rendering the turtle unfit for release and
often leading to death. Even using the NMFS STF feeding formula, very careful
monitoring of the turtles is required to ensure that an overfeeding situation does
not arise. The amount of feed is increased or decreased from the formula amount
on the basis of the appearance and activity of the turtles. Treatment of bloated
turtles is still in the experimental phase and several parameters are being evaluated,
including change of diet, change of water depth, increased rearing space, and
devices to stimulate diving and benthic behavior (Higgins and Bustinza, unpublished data).
Food consumption is used as an index of turtle health. High-quality pellet feed
floats and does not dissolve in the water, so any food remaining after 15–30 min is
an indicator that feeding activity is abnormal. It is common for sea turtles to exhibit
a period of slow eating activity in winter months or on overcast days. Sea turtles
reared in a facility that is primarily lit by natural sunlight are photoperiod-sensitive.
Slow eating behavior or a cessation of eating is a major concern and often is a
symptom of a serious health problem. Turtles are observed during and after every
feeding. Turtles that exhibit slow feeding are monitored, as are turtles that stop
feeding. A turtle that shows no interest in food for 3 consecutive days is removed
from the common tank and moved to an area of isolation, known as the STF first
care area (FCA). The FCA is housed within the same building as the general rearing
facility and is not a 100% quarantine area. The FCA contains a series of small
individual tanks where turtles can be given specific medicinal treatments and water
quality is therapeutically manipulated.
16.7 STOCKING DENSITIES
Stocking densities play a large role in sea turtle husbandry. Stocking densities
combined with feeding ultimately determines water quality. Better water quality
will most often be accompanied by a low stocking density. High stocking densities
are usually indicative of tank culture, whereas low densities are found in pens.
Four facilities were examined and stocking densities were determined directly
from literature or calculated from available information. Stocking densities varied
from 0.05–72 g/l (Table 16.1). Florida’s FWC publishes guidelines for holding
sea turtles in captivity (FWC, 2002). The FWC guidelines are primarily for
facilities that maintain only a few turtles for research, public display, and rehabilitation. The FWC-recommended stocking densities are very conservative, and it
would be difficult for large production facilities to economically meet these standards, even though they were created for the benefit of sea turtles and they should
be viewed as an ultimate goal.
1123_C16 Page 426 Tuesday, November 12, 2002 8:28 AM
The Biology of Sea Turtles, Vol. II
16.6.6 FEEDING PROBLEMS
Overfeeding of loggerheads and Kemp’s ridleys with commercially prepared diets
can cause buoyancy problems (bloating–floating). Bloating can be chronic, resulting in carapace–plastron deformities, rendering the turtle unfit for release and
often leading to death. Even using the NMFS STF feeding formula, very careful
monitoring of the turtles is required to ensure that an overfeeding situation does
not arise. The amount of feed is increased or decreased from the formula amount
on the basis of the appearance and activity of the turtles. Treatment of bloated
turtles is still in the experimental phase and several parameters are being evaluated,
including change of diet, change of water depth, increased rearing space, and
devices to stimulate diving and benthic behavior (Higgins and Bustinza, unpublished data).
Food consumption is used as an index of turtle health. High-quality pellet feed
floats and does not dissolve in the water, so any food remaining after 15–30 min is
an indicator that feeding activity is abnormal. It is common for sea turtles to exhibit
a period of slow eating activity in winter months or on overcast days. Sea turtles
reared in a facility that is primarily lit by natural sunlight are photoperiod-sensitive.
Slow eating behavior or a cessation of eating is a major concern and often is a
symptom of a serious health problem. Turtles are observed during and after every
feeding. Turtles that exhibit slow feeding are monitored, as are turtles that stop
feeding. A turtle that shows no interest in food for 3 consecutive days is removed
from the common tank and moved to an area of isolation, known as the STF first
care area (FCA). The FCA is housed within the same building as the general rearing
facility and is not a 100% quarantine area. The FCA contains a series of small
individual tanks where turtles can be given specific medicinal treatments and water
quality is therapeutically manipulated.
16.7 STOCKING DENSITIES
Stocking densities play a large role in sea turtle husbandry. Stocking densities
combined with feeding ultimately determines water quality. Better water quality
will most often be accompanied by a low stocking density. High stocking densities
are usually indicative of tank culture, whereas low densities are found in pens.
Four facilities were examined and stocking densities were determined directly
from literature or calculated from available information. Stocking densities varied
from 0.05–72 g/l (Table 16.1). Florida’s FWC publishes guidelines for holding
sea turtles in captivity (FWC, 2002). The FWC guidelines are primarily for
facilities that maintain only a few turtles for research, public display, and rehabilitation. The FWC-recommended stocking densities are very conservative, and it
would be difficult for large production facilities to economically meet these standards, even though they were created for the benefit of sea turtles and they should
be viewed as an ultimate goal.
1123_C16 Page 426 Tuesday, November 12, 2002 8:28 AM