only a habitat preference, but also the ability to remain in
such areas once they are reached. Unfortunately, if a
preference for estuarine environments exists, it may
increase the chance of being captured, since these areas are
heavily fished by man. Most of the fishing and shrimping
techniques used in estuaries can result in the capture of L.
kempi (Table 2). The large number of recaptures in
estuarine areas could also be the resuit of the greater

fishing and shrimping pressure in those areas.

Growth
Eighty-five percent of the turtles listed in Table 3 showed
increases in weight or carapace length. Eleven of the 13
turtles weighed after recapture had at least doubled in
weight. The growth rates of these L. kempi were greater

than the growth rates recorded for C. mydas. Balazs (1982)

suggested that the differences he recorded in the growth
rates of immature C. mydas were a function of each turtle’s
diet. Similarly, the carnivorous feeding habits of L. kempi
(Pritchard and Marquez, 1973) may explain the significantly
greater growth rates of the recaptured L. kempi compared to
those of herbivorous C. mydas. However, it is obvious that
other factors could also be responsible (i.e. genetic
factors, temperature, food availability). Growth rates
greater than those of the recaptured turtles are possible

for L. kempi as shown by the Miami Seaquarium and the

Galveston SeaArama-reared turtles (Figures 2 and 3). Data

- 18 -



Wilcoxon tests). The growth rates of the recaptured turtles

(carapace length gain/day) were compared to those recorded

for wild immature green turtles, Chelonia mydas,
1979; Balazs,

(Limpus,

1982) and were found to be significantly
greater (P<0.01, Wilcoxon tests).



Limpus, C. (1979). Notes on growth rates of wild turtles.
IUCN/SSC Marine Turtle Newsletter, 10, 3-5.

Maul, G.A. (1975). Circulation of the eastern Gulf of Mexico

and its possible relation to red tides. Proc. of the
Florida Red Tide Conference, Florida Mar. Res. Publ.,
8, 9-10.

Mofjeld, H.O. (1974). Tidal currents on the west Florida

shelf. Proc. of the Conference/Workshops on Marine

Environmental Implications of Offshore Drilling in the

eastern Gulf of Mexico, January 31, February 1-2, 1974,

St. Petersburg, FL., 127-130.

Pritchard, P.C.H. (1980). The conservation of sea turtles:
practices and problems. Amer. Zool., 20, 609-617.

Pritchard, P.C.H. & Marquez M., R. (1973). Kemp’s ridley
turtle or Atlantic ridley, Lepidochelys kempi. IUCN
Monograph, 2, 1-20.

Sokal, R.R. & Rohlf, F.d. (1969). Biometry. San Francisco,
W.H. Freeman and Company.

Stommel, H. (1958). The Gulf Stream. London, Cambridge
University Press.

Temple, R. F. & Martin, J.A. (1979). Surface circulation in
the northwestern Gulf of Mexico as deduced from drift
bottles. NOAA Tech. Rep. NMFS SSRF-730, 1-13.

Timko, R.E. & DeBlanc, D. (1981). Radio tracking juvenile

marine turtles. Mar. Fish. Rev., 43, 20-24.



A td iia nl lea dS

INTRODUCTION

The population of Kemp’s ridley sea turtles,
Lepidochelys Kempi, has decreased drastically in the last 36
years. This species faces extinction unless present
restoration efforts are continued. In 1947, over 40,000
nesting females were observed during a single day on this
species’ only major nesting beach (Hildebrand, 1963), but
today only 400 to 600 females nest there in an entire season
(Pritchard, 1980).

Since 1966 the Instituto Nacional de Pesca has been
protecting nesting females and eggs on the nesting beach
near Rancho Nuevo, Tamaulipas, Mexico. This conservation
effort was expanded in 1977 when a multifaceted conservation
program was initiated by the Mexican and United States
Governments in an attempt to prevent the extinction of this
sea turtle. This program involved: 1) the protection of
the nesting females and eggs on the nesting beach, 2) an
experimental imprinting project attempting to establish a
breeding population of L. kKempi on the Padre Island National
Seashore, Texas, and 3) an experimental captive-rearing
project attempting to increase the percentage of turtles
that reach sexual maturity by circumventing the suspected
high mortality of sea turtles in the natural environment

during the first year of life.



from future recaptures will be needed to determine if these
higher growth rates occur in the wild.

The wide ranges in growth rates listed in Table 3
suggest that L. kempi growth rates are quite variable. This
is further substantiated by the significant differences in
the weights and carapace lengths of the Miami Seaquarium
turtles compared to those of the Galveston SeaArama turtles

(Figures 2 and 3).

Adaptation to the Wild

Although unnatural behavior may be expected for
captive-reared turtles (Pritchard, 1980), the shortage of
information on the behavior of wild L. kempi prevents any
comparison. However, wild L. kempi have been reported from
almost all areas where the captive-reared turtles were
recaptured (Carr, 1956, 1980; Pritchard and Marquez, 1973).
This is an encouraging indication that captive-reared L.
kKempi are behaving normally. The growth of the recaptured
turtles (Table 3) indicates that they have adapted to life
in the wild. Additionally, of the 54 turtles recaptured,
80% were healthy and were released. Thus the above

information suggests that captive-reared L. kempi can adapt

to the wild.



Figure 1.

Figure 2.

Figure 3.

Figure Legends

Release sites and recapture locations of
Lepidochelys Kempi released in the Gulf of Mexico
during 1979. In locations where more than one
recapture occurred, the number adjacent to those

locations indicates the number of recaptures.

Weight versus age plot for Lepidochelys kempi
under captive and wild conditions. Points
representing the weights of the Miami Seaquarium
and the Galveston SeaArama turtles are mean
values, whereas the triangles representing the
weights of recaptured turtles are individual

values.

Length versus age plot for Lepidochelys kempi
under captive and wild conditions. Points
representing the lengths of the Miami Seaquarium
and the Galveston SeaArama turties are mean
values, whereas the triangles representing the
lengths of recaptured turtles are individual
values. All length values indicate straight line

carapace lengths.



REFERENCES

Balazs, G.H. (1982). Growth rates of immature green turtles
in the Hawaiian Archipelago. In: Biology and

Conservation of Sea Turtles, ed. by Karen A. Bjorndal,

Washington D.C., Smithsonian Institution Press.

Carr, A. (1956). The Windward Road. New York, Alfred A.
Knopf.

Carr, A. (1980). Problems of sea turtle ecology. Amer.
Zool., 20, 489-498.

Carr, A.F. & Caldwell, D.K. (1956). The ecology and
migration of sea turtles, 1. Results of field work in
Florida, 1955. Am. Mus. Nov. 1973, 1-23.

Hildebrand, H.H. (1963). Hallazgo del area de anidacion de
la tortuga marina "lora", Lepidochelys kempi (Garman)
en la costa occidental del Golfo de Mexico (Rept.,
Chel.). Ciencia,. 22, 105-112.

Ingham, M.C.(1979). Marine environmental conditions off the
Atlantic and Gulf Coasts of the United States, January
1977-March 1978. Mar. Fish. Rev., 41, 35-47.

Klima, E.F. & McVey, U.P. (1982). Head-starting the Kemp’s
ridley sea turtle, Lepidochelys kempi. In: Biology and

Conservation of Sea Turtles, ed. by Karen Bjorndal,

Washington D.C., Smithsonian Institution Press.
Lee, T.N. & Mayer, D.A. (1977). Low-frequency current
variability and spin-off eddies along the shelf off

southeast Florida. JU. Mar. Res., 35, 193-220.

- 241 -



Padre Island Releases

The two turtles recaptured from the Padre Island
National Seashore release were both found northeast of the
release area along the Texas coast. Considering the long
periods these turtles had been in the wild (309 and 392
days) they were relatively short distances away from the
release site (322 and 161 km). The seasonal reversal of
currents along the Texas coast (Temple and Martin, 1979)
could have been responsible for these short net movements if
the current was a major factor controlling the turtles’
movements. Additionally, movements into the Texas bay
system could also have been responsible for these short net
movements. Turtle G2313 was recaptured in a bay near
Palacious. While in the bays, turtles would not be exposed
to. the displacement effects of longshore and offshore
currents. These turtles were also larger than the turtles
that were released at the other release sites and should
have had better swimming abilities.

General Characteristics of L. kempi Movements

The movements of the recaptured turtles and the wide
geographical range from which immature L. kempi have been
reported in the past, suggest that large variations exist in
the movements of immature L. kempi. This information also
suggests that the early life history of this species
represents a time when these turtles disperse throughout the

Gulf of Mexico and the North Atlantic. Our data also



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Florida, during the first Florida Bay release. The
movements of this current drogue were then monitored from
shore-receiving stations for 3 days before the signal was
lost. At Padre Island the turtles were released from the
beach.

Thirty-eight of the captive-reared turtles were not
released. Twenty-eight were sent to the Miami Seaquarium
and 10 to the Galveston SeaArama for continued
captive-rearing in order to create a potential breeding
stock for captive reproduction and to obtain data on their
growth rates for comparisons with growth rates of L. kempi

in the wild.



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captive-reared turtles on fixed feeding schedules, and
therefore may not represent the growth rate in the wild.

The experimental captive rearing-program conducted by
the National Marine Fisheries Service provides the means of
evaluating-captive rearing as a conservation technique for
sea turtles. Additionally, this program provides an
opportunity to study the movements and growth of immature L.
kempi in the wild. This program raises approximately 2,000
L. Kempi per year for the first 8 to 12 months of their
lives. These turtles are then released into the Gulf of
Mexico in areas where immature L. kempi have historically
been Known to occur. The recapture of tagged individuals
provides valuable information on the growth and movements of
these immature turtles in the wild. These data may also be
a reasonable indicator of the growth and movements of
immature L. kempi in the natural (noncaptive-reared)
population . We report here on the recapture of turtles
released during the initial year of this progam (1979) with

emphasis on their movements, growth, and their survival in

the wild.



Although this species is the subject of intense
conservation work, many aspects of its life history are not
clearly understood. A better understanding of its life
history could enhance present conservation efforts. Most of
our present knowledge about this turtle stems from data
collected on the nesting beach and from reports of its
occurrence in the Gulf of Mexico and the Atlantic. Both
immature and mature L. Kempi have been reported throughout
most areas of the Gulf of Mexico, and immature individuals
have also been found along the Atlantic coasts of North
America and Europe (Carr, 1956, 1980; Pritchard and Marquez,
1973). Data collected on the nesting beach show that
hatchlings enter the Gulf of Mexico at an approximate weight
of 18 g and an approximate carapace length of 4 cm. If they
are female and survive to sexual maturity, they return to
the Rancho Nuevo area to nest at a minimum weight of 32 kg
and a minimum carapace length of 58 cm (Pritchard and
Marquez, 1973). The movements and behavior of L. kempi
during their years of immaturity are poorly understood,
although certain areas of the Gulf of Mexico and the
Atlantic have had relatively high concentrations of
immatures (Carr, 1980; Carr and Caldwell, 1956) Furthermore,
the time required for L. kempi to reach sexual maturity is
presently speculative. Pritchard and Marquez (1973)

suggested that sexual maturity is reached after 6 years.

However, many of their data were obtained from


support Carr's theory that strong ocean currents such as the
Gulf Stream act as dispersal mechanisms for L. kempi (Carr,
1956, 1980). This also appears to be the case for Chelonia
mydas (Witham, 1980). This idea is further supported by the
distribution of wild L. kempi, since immature individuals
have been reported from various areas of the Atlantic coasts
of North America and Europe (Carr, 1956, 1980; Pritchard and
Marquez, 1973). Nevertheless, the effects of the Gulf
Stream appear to be temporary (at least for some turtles),
because the recaptured turtles apparently moved out of the
Gulf Stream and into nearshore waters.

In slower-moving waters (i.e. Homosassa area), the L.
kempi exhibited a variety of movements. This suggests that
in areas without powerful currents, L. kempi of
approximately 0.5 to 1.0 kg are capable of making a
transition from a planktonic animal, as very young sea
turtles are assumed to be (Carr, 1980; Witham, 1980), into a
necktonic animal. Thus these turtles would appear to be at
the end of their so called “lost year" (Carr, 1980; Witham,
1980), if they are in areas without powerful currents.
Further evidence for this was shown by four turtles (G0074,
G0460, G0904, G2831, Table 2) that were recaptured a second
time in the same general area as their initial recapture,
after intervals ranging from 14 to 31 days. These four

turtles as well as at least 12 of the other recaptured

turtles were found in or near esturaries, suggesting not



by Klima and McVey (1982) and by Timko and DeBlanc (1981).
Wibbels (1984) presented a detailed analysis of the
movements recorded in the radio-tracking study.

Several release sites were used to investigate an
optimal release site for future releases. Florida Bay and
Homosassa release sites were chosen because these areas were
historically Known for an abundance of immature L. kempi
(Carr, 1956; Carr and Caldwell, 1956). Furthermore, these
areas are considered to be ideal habitats for young sea
turtles (Carr, 1956; Carr and Caldwell, 1956). Padre Island
was chosen as a release site in order to reexpose the
turtles to any stimulus that they may have imprinted on as
hatchlings.

The release sites, release dates, average weight, and
average carapace length of turtles released at each site and
the number of turtles released at each release site are
given in Table 1. Turtles were released individually from a
slow-moving boat (5 km/hr) at approximately 10 m intervals
during the Florida Bay and Homosassa releases. During these
releases, divers followed 10 turtles for up to 1 hr to
monitor initial behavior after release. To obtain
information on the currents affecting these turtles, 12
drift bottles were disbursed during each of the releases at
Florida Bay and at Homosassa. These drift bottles contained
instructions for reporting their recovery location. A radio

current drogue was also released i2 km off Cape Sable,



Wibbels, T.R. (1984). Orientation characteristics of

immature Kemp’s ridley sea turtles, Lepidochely kempi.

NOAA Tech. Mem. NMFS-SEFC-131.
Witham, R. (1980). The “lost year“ question in young sea

turtles. Amer. Zool., 20, 525-530.

cat



#°\, NOAA Technical Memorandum
. el; NMFS-SEFC-145

THE GROWTH AND MOVEMENTS OF CAP-—
TIVE-REARED KEMP’S RIDLEY SEA
TURTLES, LEPIDOCHELYS KEMPI,

FOLLOWING THEIR RELEASE IN
THE GULF OF MEXICO.

U.S. DEPARTMENT OF COMMERCE

ic Adi
SEPTEMBER —~— a

Southeast Fisheries Center
1 984 Galveston Laboratory

Galveston, Texas 77550


Chincoteague, Virginia (Figure 1B). Two turtles from the
Padre Island release were recaptured (Figure 1A); both had
moved northeast along the Texas coast, one to Palacious,
Texas and one to Galveston, Texas.

Drift bottles released in Florida Bay were recovered
primarily near the Florida Keys, except for 1 recovery from
Boca Raton, Florida (225 km), and two recoveries from Cocoa
Beach, Florida (484 km). Drift bottles were recovered in
the Florida Keys in as few as 13 days and at Cocoa Beach
within 50 days of their release. During the 3 days we
tracked the current drogue, it drifted slowly north of Cape
Sable, but the signal was lost after a frontal system
brought strong northerly winds. Because of the short
duration of tracking the current drogue, only the drift
bottles were used to evaluate the movements of the turtles
following the Florida Bay releases. None of the drift
bottles released near Homosassa were recovered.

The turtles were recaptured by a variety of methods as
indicated in Table 2. Ten turtles were found alive on
beaches: 3 were injured, 2 were partially covered with tar,
1 was reportedly found entangled in a mass of Sargassum, and
4 were on the beach for unknown causes. Two turtles were
found dead from unknown causes on beaches. Eighty percent
of the recaptured turtles were in good health and were
released (Table 2). The tags from 25% of the turtles that

were recaptured alive were removed before the turtles were


RESULTS

During the Fiorida Bay and Homosassa releases, most
turtles swam rapidly away from the boat. Divers following
turties noted predominantly near-surface swimming and
evasive behavior if turtles were approached closely (within
approximately 4 m).

As of December 1980, 61 recaptures had been reported
from 2,006 turtles released in 1979 (Table 2). Seven
turtles were recaptured twice. The recapture rates are 4.3%
for turtles released in the Bay of Florida, 2.0% for turtles
released near Homosassa, and 1.8% for those released from
Padre Island, with an overall recapture rate of 2.7%. The
distance of each recaptured turtle’s net movement and its
elapsed time in the wild are shown in Table 2. The average
net movement from the release site was 714.4 km with a range
from 2 to 2,358 km; the average time between release and
recapture was 241.4 days with a range from 1 to 625 days;
and the average net movement per day was 3.1 km with a range
from 0.2 to 11.5 km/day.

Turtles released in Florida Bay were recaptured in an
area extending from the Florida Keys, north along the
Atlantic coast, to Long Island, New York (Figure 1A). No
westerly movements were recorded for turtles released in
Florida Bay. Turtles released near Homosassa were
recaptured in the Gulf of Mexico as far west as Matagorda

Bay, Texas, and in the Atlantic as far north as



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METHODS AND MATERIALS

The turtles used in this captive-rearing program were
hatched from eggs laid on the beach near Rancho Nuevo,
Mexico. Approximately 60% of captive-reared turtles were
involved in an experiment that attempted to imprint them to
the beach at Padre Island National Seashore in order to
start a breeding population there. Those eggs were
incubated in boxes containing Padre Island sand and were
transferred to Padre Island before hatching. After
hatching, the turtles were allowed to crawl down the beach
and into the surf before they were retrieved. The other 40%
of the turtles used in this study were hatched on the
nesting beach near Rancho Nuevo. All hatchlings were flown
to Galveston, Texas, where they were reared for 8 to 11
months with the methods established by the National Marine
Fisheries Service (Klima and McVey, 1982).

Before their release, all turtles were weighed,
measured, and tagged with monel flipper tags (National Band
and Tag Co. size 681)4 on the trailing edge of the right
front flipper. Each flipper tag contained an identification
number and an address for reporting information about the
turtle to the proper authority. Additionally, 22 turtles
were equipped with radio transmitters in order to track the

initial movements of the released turties. The preliminary

results of these radio-tracking experiments were discussed



ACKNOWLEDGEMENTS

This project was a cooperative venture between the
National Marine Fisheries Service (Southeast Fisheries
Center), the Instituto Nacional de Pesca, the U.S. Fish and
Wildlife Service, Texas Parks and Wildlife Departent, and
the Florida Audubon Society. We especially thank Rene
Marquez, Jack Woody, and Ray Wheeler for their personal
efforts in this cooperative venture. We are also thankful
to Fred Berry, Peter Pritchard, Robert LeBoeuf, Alfred
Loeblich, III, and Steven McCommas for critically reviewing
this manuscript, Dennis Koi for helping with computer
analysis, and William Pringle for recording and furnishing
data on the Seaquarium turties. We would also like to
express a special thanks to John Kerivan of Galveston
SeaArama and Warren Zeiler of Miami Seaquarium for their

rearing of turtles for a potential breeding stock.



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ABSTRACT

As part of an international conservation program that
is attempting to save the endangered Kemp’s ridley sea
turtle, Lepidochelys kempi, 2,026 captive-reared L. kempi
were tagged and released in the Gulf of Mexico in 1979.
Fifty-four of these turtles have been recaptured. The
diversity of means by which the recaptures were made
indicated that many of the fishing and shrimping techniques
used by man can result in the capture of this sea turtle.
These recaptures have provided valuable data on the
movements and the growth of young (8 to 28 months old) L.
kempi in the wild. Turtles released in Florida Bay were
recaptured along the Atlantic coast of the United States,
suggesting that the Gulf Stream played a major role in their
dispersal. However, turtles released in calmer waters near
Homosassa, Florida, moved in a variety of directions,
indicating that immature animals weighing 0.5 to 1.0 kg may
be capable of making a transition from a planktonic to a
nektonic existence in relatively calm waters. Eighteen of
the recaptured turtles were weighed and/or measured. These
turtles exhibited average weight gains of 5.1 g/day and
average carapace length gains of 0.024 cm/day. The
recaptured turtles’ growth and movements indicate that

captive-reared L. kempi can adapt successfully to life in

the wild.



DISCUSSION

The data obtained from the turtle recaptures indicate
that a significant portion of the captive-reared L. kempi
have adapted to wild conditions and have dispersed rapidly
and widely from their points of release. As would be
expected, the location of the release appears to be an
important factor affecting the dispersal of the turtles.
Each release location resulted in a different dispersal
pattern and future release locations should be chosen
relative to their effects on the turtles’ movements. The
following sections contain information obtained from the
release and recapture of captive-reared L. kempi released in

1979.

Florida Bay Releases

The majority (5 of 8) of the drift bottles recovered
from the Florida Bay releases were found near the Florida
Keys, indicating a net southerly movement of the surface
currents following the releases. The numerous turtles
recaptured near the Florida Keys suggest that the local
currents significantly influenced these turtles movements.
The 3 drift bottles that were recovered on the Atlantic
coast of the United States apparently drifted southeast
through the Florida Keys and into the influence of the
Florida Current. Once in the Florida Current these bottles

would have been transported northward along the Atlantic

- 13 -



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moved north along the Atlantic coast of the United States.
These northerly movements were probably influenced by the
Gulf Stream, although nearshore paths are also a
possibility. Other turtles from the Homosassa releases
moved north and west along the Gulf coast as far as
Matagorda Bay, Texas. Homosassa released turtles also
exhibited large variation in average net movement per day.
An example of this for turtles moving north and west from
the release site is turtle G2155 (Table 2), which was
recaptured 1,384 km from the release site after 315 days in
the wild (4.4 km/day), whereas turtle G2146 was recaptured
only 80 km from the release site after 434 days in the wild
(0.2 km/day).

This wide range in movements suggests that these
turtles were more nektonic than the Florida Bay released
turtles. This could have been the result of weaker and more
variable currents in the Homosassa area, which would have
exerted less of an influence on the turtles’ movements. The
currents near Homosassa are produced by winds and tides
(Mofjeld, 1974), whereas the currents of Florida Bay are
produced not only by winds and tides but also by eddies
formed by the Loop Current that are entrained by the Florida

Current near the Florida Keys (Maul, 1975).



NOTICE
THIS TECHNICAL MEMORANDUM SHOULD BE CITED AS FOLLOWS:

McVey, JAMES P. AND THANE WIBBELS. 1984,
THE GROWTH AND MOVEMENTS OF CAPTIVE-REARED
KEMP'S RIDLEY SEA TURTLES, LEPIDOCHELYS KEMPL,
FOLLOWING THEIR RELEASE IN THE GULF OF MEXICO.
NOAA TECHNCIAL MEMORANDUM_NMFS - SEFC - 145,
25 P, PLUS 3 FIGURES AND 3 TABLES,

IT CAN BE OBTAINED BY_WRITING TO THE NATIONAL TECHNICAL
INFORMATION SERVICE, 5258 PoRT ROYAL ROAD, SPRINGFIELD,
VIRGINIA 22161,

\
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FOOTNOTES

1. This study was made possible through permits from the
Mexican Government (Permit Nos. 1978-ABC-IV-0751, 27611-8786
and 1979-ABC-IV-1258). This study is a contribution from
the Southeast Fisheries Center, Galveston Laboratory,

National Marine Fisheries Service, NOAA.

2. Current address: NOAA National Sea Grant Program:-6010-~

Executive Blvd., Rockville, MD 20852.

3. Current address: Department of Biology, Texas A&M

University, College Station, TX 77843.

4. Use of this product does not constitute an endorsement.



| @S NOAA Technical Memorandum
| ws NMFS-SEFC-145

THE GROWTH AND MOVEMENTS OF CAP-
TIVE-REARED KEMP’S RIDLEY SEA
TURTLES, LEPIDOCHELYS KEMPIi,

FOLLOWING THEIR RELEASE IN
THE GULF OF MEXICO.”

BY

2
James P. McVey and Thane Wibbels”

U. S. DEPARTMENT OF COMMERCE
Maicoim Baldrige, Secretary

National Oceanic and Atmospheric Administration
John V. Byrne, Administrator

National Marine Fisheries Service
William G. Gordon, Assistant Administrator for Fisheries

SEPTEMBER 1984

Technical Memorandums are used for documentation and timely commu-~
nication of preliminary results, interim reports , or special-purpose
information, and have not received complete formal review, editorial

control, or detailed editing.


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released. This may have been due to the inscription on the
tag which read "Return to Univ. of Florida." We have since
changed the tags to read “Write to SEFC, Miami," which will
reduce the number of tags removed from subsequent
recaptures.

Changes in weight and/or carapace length could be
determined for only 33% of the recaptured turtles (Table 3).
Weight changes ranged from -2.2 to +11.7 g/day with an
average of +5.1 g/day. Straight line carapace length
changes ranged from -0.012 to 0.053 cm/day with an average
of 0.024 cm/day. The weights and straight line carapace
lengths of these turtles were compared with those of the
captive-reared turtles at the Miami Seaquarium and the
Galveston SeaArama (Figures 2 and 3). The weights and
carapace lengths of the Miami Seaquarium reared turtles were
significantly greater than those of the recaptured turtles
(P<0.005, probabilities from t-tests and Wilcoxon tests were
combined according to Sokal and Rohlf, 1969, p. 623).
Weights and carapace lengths of the turtles reared at the
Galveston SeaArama were not recorded until after February
1980. The data recorded after that date show that the
Galveston SeaArama turtles also had significantly greater
weights and carapace lengths than the recaptured turtles
(P<0.01, Wilcoxon tests). However, the weights and carapace

lengths of the Galveston SeaArama turtles were significantly

less than those of the Miami Seaquarium turtles (P<0.01,



coast (Stommel, 1958) until they moved shoreward in cyclonic
eddies of the Gulf Stream or in wind-generated onshore
currents (Lee and Mayer, 1977; Ingham, 1979). Similarly,
turtles released in the Florida Bay and recovered on the
Atlantic coast of the United States may have entered the
Gulf Stream and subsequently been carried northward until
they moved near shore. These onshore movements could be
accomplished by the same methods indicated for the drift
bottles as well as by active swimming. There is also the
possibility that these turtles moved northward in nearshore
waters and were not carried by the Gulf Stream. However, we
concur with Carr (1956; 1980) and Witham (1980) that the
most probable dispersion mechanism is the Gulf Stream.

From the recovery locations of turtles and drift
bottles released in Florida Bay, it appears that ocean
currents played a major role in the movements of these
turtles. This idea is further substantiated by the total
lack of turtle recoveries west or north in the Gulf of
Mexico in which turtles would have had to overcome the
influence of the net southerly currents following their
release.

Homosassa Releases

The recapture locations of turtles released near

Homosassa indicate a variety of movement patterns. Many of

these turtles apparently moved south from the release sites

as far as the Florida Keys. Some of these turtles then