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A Review on the Nesting Beaches of Loggerhead Turtle, Caretta caretta, on the Southwestern Mediterranean Coasts of Turkey

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Most nesting by loggerhead turtles in Turkey has been recorded at 20 sites along the Mediterranean coast. In addition, sites primarily used by green turtles are also used by loggerheads. The annual number of loggerhead nests recorded on these 20 beaches ranges from 663 to 1991, with a mean of 1267 nests per season. We review the biology of nesting and predation at five of the most important and more regularly investigated loggerhead nesting sites (Dalyan, Fethiye, Patara, Belek and Kizilot). These five beaches may host up to 920 nests per season. With approximately 307 adults per season, the Dalyan beach has the highest capacity in terms of numbers of nests and of nesting females. Hatching success at the five beaches was negatively affected by fox predation (93% of the predated eggs on the beaches), crab predation (29.5% of the predated hatchlings), and light-pollution (42% of the hatchlings). In addition, predation by beetle larvae has been observed on the eggs at Fethiye beach (17.6% of the predated eggs at this site).
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HERPETOLOGICAL JOURNAL, Vol. 13, pp. 27-32 (2003)
A REVIEW OF THE BIOLOGY OF THE LOGGERHEAD TURTLE, CARETTA
CARETTA, AT FIVE MAJOR NESTING BEACHES ON THE SOUTH-WESTERN
MEDITERRANEAN COAST OF TURKEY
OGUZ TÜRKOZAN1, ERTAN TASKAVAK2 AND ÇETIN ILGAZ3
1Adnan Menderes University, Faculty of Science and Art, Department of Biology, 09010 Aydin, Turkey
2Ege University, Faculty of Fisheries, 35100 Bornova-Izmir, Turkey
3Dokuz Eylül University, Faculty of Education, Department of Biology, 35150 Buca-Izmir, Turkey
Most nesting by loggerhead turtles in Turkey has been recorded at 20 sites along the
Mediterranean coast. In addition, sites primarily used by green turtles are also used by
loggerheads. The annual number of loggerhead nests recorded on these 20 beaches ranges from
663 to 1991, with a mean of 1267 nests per season. We review the biology of nesting and predation
at five of the most important and more regularly investigated loggerhead nesting sites (Dalyan,
Fethiye, Patara, Belek and Kizilot). These five beaches may host up to 920 nests per season. With
approximately 307 adults per season, the Dalyan beach has the highest capacity in terms of
numbers of nests and of nesting females. Hatching success at the five beaches was negatively
affected by fox predation (93% of the predated eggs on the beaches), crab predation (29.5% of
the predated hatchlings), and light-pollution (42% of the hatchlings). In addition, predation by
beetle larvae has been observed on the eggs at Fethiye beach (17.6% of the predated eggs at this
site).
Key words: Chelonia, egg, hatchling, nesting, predation
INTRODUCTION
In the Mediterranean, the major nesting grounds for
loggerhead turtles, Caretta caretta (Linnaeus, 1758) are
in Turkey and Greece (Baran & Kasparek, 1989;
Margaritoulis, 2000), with smaller numbers recorded in
Cyprus (Broderick & Godley, 1996), Egypt (Kasparek,
1993; Clarke et al., 2000), Libya (Laurent et al., 1995),
Tunisia (Laurent et al., 1990), Israel (Kuller, 1999) and
Syria (Kasparek, 1995). According to the previously
substantiated records (Baran & Kasparek, 1989; Baran
et al., 1998; Taskavak et al., 1998; Oruç et al., 1997),
three species of marine turtle – Caretta caretta, Chelo-
nia mydas and Dermochelys coricea – are included in
the chelonian fauna of Turkey. Only the first two are
known to nest on the Turkish coast of the Mediterra-
nean. The first nesting records of Caretta caretta and
Chelonia mydas from the Turkish coasts were by
Hathaway (1972). Basoglu (1973) and Basoglu & Baran
(1982) gave information on the carapace plates of C.
caretta found at Izmir, Köycegiz and Fethiye. Geldiay &
Koray (1982), Geldiay et al. (1982) and Geldiay (1983,
1984) described marine turtle populations and their pro-
tection on the Mediterranean coasts of Turkey. Baran &
Kasparek (1989) described the first comprehensive sur-
vey of the Turkish Mediterranean coast for turtle
nesting sites. Its primary objective was to locate nesting
sites and to allow assessment of their relative impor-
tance. More recently, various population studies have
been carried out on certain beaches, and problems af-
Correspondence: E. Taskavak, E. Ü., Su Ürünleri Fakültesi,
Temel Bilimler Bölümü Balikçilik Anabilim Dali, 35100 Iz-
mir, Turkey. E-mail: taskavak@sufak.ege.edu.tr
fecting the turtles on the nesting beaches have been
determined (Canbolat, 1991; Erk’akan, 1993; Baran et al.,
1992; Baran, 1993a,b; Baran et al., 1994; Baran et al.,
1996; Türkozan & Baran, 1996; Baran & Türkozan, 1996).
Almost half the recorded nesting sites of the Mediter-
ranean loggerhead – and a large proportion of those for
green turtles – are found on Turkish beaches
(Groombridge, 1988). Although 17 important nesting
sites in Turkey were given by Yerli & Demirayak
(1996), only 15 of them were marked on the map given.
A total of 13 beaches was considered as constituting the
main nesting areas for marine turtles in Turkey (Baran &
Kasparek, 1989; Baran et al., 1992; Groombridge, 1994).
From west to east, these beaches include: Dalyan,
Dalaman, Fethiye, Patara, Kumluca, Belek, Kizilot,
Demirtas Gazipasa, Göksu Deltasi, Kazanli, Akyatan and
Samandag (Fig. 1). Apart from these main nesting
beaches, there are others which do not hold such large
numbers, but which are still of vital importance for sea
turtles (Baran & Kasparek, 1989). These are Ekincik,
Kale, Tekirova and Anamur (Fig. 1). These four second-
arily important nesting beaches were also listed by
Groombridge (1994). The beach at Demirtas (Fig. 1)
given as the main nesting beach by Baran & Kasparek
(1989) was not given in the updated list given by Yerli &
Demirayak (1996). Additionally, the nesting beach at
Çirali (Fig. 1), which was not given by Baran & Kasparek
(1989), appeared for the first time as a main nesting
beach in the map of Yerli & Demirayak (1996). In addition
to the localities given above, two additional sites with
less nesting (Agyatan and Yumurtalik) were given by
Yerli & Canbolat (1998). All these localities are marked in
Fig. 1. According to fieldwork carried out over the last 25
FIG. 1. The localities where the loggerhead nesting beaches are recorded (Upper case indicates main nesting beaches; lower case,
secondary nesting beaches; italics, additional unsubstantiated records).
years, green turtle nesting is mostly limited to a few east-
ern beaches (Kazanli, Akyatan and Samandagi (Fig. 1).
This study aims to provide information on the popula-
tion and nesting status of the loggerhead turtle, Caretta
caretta, on the south-western beaches (Dalyan,
Fethiye, Patara, Belek and Kizilot, which appear to be the
most important loggerhead beaches in Turkey. As such,
the first four have been designated as Specially Pro-
tected Areas.
MATERIALS AND METHODS
Data were compiled from previously published
sources and unpublished research reports. All records
were scanned and the numbers of loggerhead nests re-
corded were collated (Table 1). At the five most
important beaches, increased observer effort over the
years allowed for a comparative review to be under-
taken. It is likely that some nesting will have occurred
undetected at sites along the Aegean and Mediterra-
nean coasts not subject to monitoring, leading to
underestimates of population size and hatchling recruit-
ment
The values for total emergence, total number of nests,
number of eggs, hatchlings reaching the sea and nest
densities are presented in Table 2 for five beaches that
have been monitored since 1982. It should be noted that
not all of the studies listed in Table 2 were conducted
throughout the entire nesting season each year. Geldiay
et al. (1982), and Groombridge (1994) extrapolated the in-
formation from short surveys. Observations on the
Dalyan beach were carried out at intervals of one or two
weeks, and counts of tracks and nests were made during
the day (Geldiay et al., 1982). The total number of nests
recorded at Dalyan for 1987 was estimated from the data
collected between 4 June and 5 July (Groombridge,
1994). Except for the Fethiye beach, Yerli & Demirayak
(1996) started the regular observations on four beaches
after 20 June 1994. Baran et al. (1996) and Sak (1998)
started regular studies on Dalyan and Patara, and Belek,
respectively, after 20 July 1996. Yerli & Demirayak
(1996), Kaska (1993) and Turkozan (2000) studied 8.5 km,
5 km and 4.5 km, respectively, of the Kizilot beach, which
is 16.2 km in total length; observations by Kaska (1993)
and Turkozan (2000) were made daily and included
whole breeding seasons. The remaining data given in
Table 2 are regular and include overall breeding sea-
sons.
RESULTS
DALYAN BEACH
This site is in the transitional zone between the
Aegean and Mediterranean regions and consists of a
beach approximately 4.2 km in length. The values for
Dalyan were compiled from the studies carried out by
various researchers in different years (Table 2). A total
of 2119 nests was recorded, with a mean of 193 nests per
season, over 11 breeding seasons. The number of nests
per season varies from 57 to 330. Using the assumption
that each female nests an average of three times in a sea-
son (Groombridge, 1994), between 19 and 110
loggerhead turtles nest annually on the beach.
Information on predation was compiled over six years
(1991 to 1997). During these six seasons, a total of 17 584
eggs was destroyed (Table 3). Of these, 17 385 eggs
(98.9%) were destroyed by foxes and 199 (1.1%) by
crabs. On the other hand, a total of 2833 hatchlings was
destroyed over the seasons of 1991-1993 and 1997. Of
these, 908 (32.1 %) were killed by foxes and 1703 (60.1%)
by crabs. Strong sunlight and dehydration caused 199
hatchlings (7.0%) to die. Birds destroyed 23 hatchlings
(0.8%).
FETHIYE BEACH
Approximately 8.3 km of the Fethiye beach, Specially
Protected Area, situated within the boundaries of
Vilayet Mugla, was examined for five nesting seasons
from 1993 to 1997 (Table 2). This region was also desig-
O. TÜRKOZAN ET AL.28
NESTING OF LOGGERHEAD TURTLES IN TURKEY
dogs (3.9%). Meanwhile, 36 (1.7%) were accidentally de-
stroyed by researchers whilst using a metal rod to
search for and locate the clutches. A plant root de-
stroyed one egg (0.04 %) and human activities (e.g. sand
extraction, beach utilization for tourism, light pollution,
cattle trampling) caused the loss of 86 eggs (3.9%). A
total of 743 hatchlings was destroyed from 1994 to 1997.
Of these, 405 were destroyed by foxes (54.5 %), 52 by
dogs (6.9%) and 14 by ghost crabs (1.8 %). Birds de-
stroyed 93 hatchlings (12.5%). Strong sunlight and
dehydration caused 173 hatchlings (23.2%) to die. Cars
ran over six hatchlings (0.8%) on the beach.
Nesting success (the proportion of adult emergences
resulting in egg laying) ranged from 21.5% to 49.2% be-
tween the years 1993 and 1997. The hatching success of
the eggs ranged from 58.1% to 68.4 %. The total number
of hatchlings reaching the sea as a percentage of the
eggs hatching varied from 67.2% to 85.5%.
PATARA BEACH
Data on an 11.8 km-long sandy strip were compiled
for six breeding seasons between 1990 and 1997 (not
1991 or 1995). A total of 315 nests was recorded, with a
mean of 53 (Table 2). The number of nests varied from 33
to 85 for the years 1990 to 1997. It is estimated that ap-
proximately 11-28 loggerhead turtles nest annually at
this site. Predation of eggs was recorded for the years
1992, 1993, 1996 and 1997. During these periods, a total
of 2547 eggs was destroyed. Of these, 1783 eggs were
killed solely by foxes (69.2%) and 207 by crabs (8.0%).
Birds destroyed one egg (0.04%). Foxes and crabs in
combination destroyed 586 eggs (22.7%).
During the 1992 and 1993 breeding seasons, a total of
460 hatchlings was lost. Of these, 60 were killed by foxes
(13.0%) and 378 by crabs (82.2%). Birds destroyed one
hatchling (0.2%). Strong sunlight and dehydration
caused 21 hatchlings (4.6%) to die.
BELEK BEACH
For three breeding seasons, we compiled data on
Belek beach, approximately 25 km in length and situ-
ated 40 km west of Antalya (Table 2). A total of 389
nests was recorded, with a mean of 130. The number of
nests per season varied from 68 to 168. It is estimated
that 23-56 loggerhead turtles nest annually on the
beach. Some 616 eggs were destroyed either by foxes or
dogs during the 1996 and 1997 breeding seasons. Of
3276 hatchlings destroyed on the beach, 89 were killed
by ghost crabs (2.7%). Light-pollution, causing
hatchling disorientation, and strong sunlight and dehy-
dration caused the loss of 1263 hatchlings (38.5%) and
52 hatchlings (1.6%) respectively. Furthermore, 1872
hatchlings (57.1%) were disoriented.
KIZILOT BEACH
The Kizilot beach, 16.2 km in length and situated
within the boundaries of Vilayet Antalya, was examined
TABLE 1. Nesting efforts of the loggerhead turtle in Turkey
(Ekincik ref: Baran et al., 1994. Dalyan ref: Erk’akan, 1993;
Geldiay et al., 1982; Groombridge, 1994; Baran et al., 1996;
Erk’akan, 1993; Baran et al., 1992; Canbolat, 1996; Yerli &
Demirayak, 1996; Baran et al., 1996; Ilgaz, 1998. Dalaman ref:
Yerli & Demirayak, 1996; Yerli et al., 1998. Fethiye ref:
Türkozan & Baran, 1996; Baran & Türkozan, 1996; Türkozan
2000. Patara ref: Baran et al., 1992; Canbolat, 1996; Yerli &
Demirayak, 1996; Baran, 1993a; Taskin, 1998. Kale ref: Yerli
& Demirayak, 1996; Yerli et al., 1998. Kumluca ref: Yerli &
Demirayak, 1996, Yerli et al., 1998; Baran & Kasparek, 1989;
Baran et al., 1992. Çirali ref: Yerli & Demirayak, 1996; Yerli et
al., 1998. Tekirova ref: Yerli, et al., 1998 Belek ref: Yerli &
Demirayak, 1996; Sak, 1998; Yerli et al., 1998. Kizilot ref:
Kaska, 1993; Yerli & Demirayak, 1996; Yerli et al., 1998;
Türkozan, 2000. Demirtas ref: Baran & Kasparek, 1989; Yerli
& Canbolat, 1998. Gazipasa ref: Yerli & Demirayak, 1996;
Yerli & Canbolat, 1998. Anamur ref: Baran et al., 1992; Yerli
& Demirayak, 1996; Yerli & Canbolat, 1998. Göksu Deltasi:
Peters & Verhoeven, 1992. Akyatan ref: Brown & Mcdonald,
1995; Yerli & Demirayak, 1996; Yerli & Canbolat, 1998.
Aureggi et al. 1999. Agyatan ref: Yerli & Canbolat, 1998.
Kazanli ref: Baran et al., 1992; Yerli & Canbolat, 1998;
Durmus, 1998. Yumurtalik ref: Yerli & Canbolat, 1998.
Samandag ref: Yerli & Canbolat, 1998).
No. seasons Average Range
no. nests
Ekincik 1 8 8-8
Dalyan 11 193 57-330
Dalaman 2 71 69-73
Fethiye 8 122 88-191
Patara 6 53 33-85
Kale 2 74 39-109
Kumluca 4 141 35-305
Çirali (Olimpos) 2 23 12-34
Tekirova 1 4 4-4
Belek 4 122 68-168
Kizilot 5 139 50-270
Demirtas 2 62 44-80
Gazipasa 2 14 14-14
Anamur 3 159 96-195
Göksu Deltasi 2 63 36-89
Akyatan 4 10 3-23
Agyatan 1 2 2-2
Kazanli 4 3 1-7
Yumurtalik 1 1 1-1
Samandag 1 3 3-3
TOTAL 1267 663-1991
nated as a feeding ground for juvenile green turtles
(Türkozan & Durmus, 2000). A total of 650 nests was
recorded, with a mean of 130 per season over five breed-
ing seasons. The number of nests per season varied
from 88 to 191 during the years 1993 to 1997. This means
that approximately 29-64 loggerhead turtles nest annu-
ally on the beach.
Between the years 1994 and 1997, a total of 2091 eggs
was destroyed. Of these, 1515 were predated by foxes
(72.4%), 370 by coleopteran larvae (17.6%) and 83 by
29
1982 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997
A B C D E,P F F&J G,K L H H,L, I,L,
O N,O
Dalyan
Total emergence ? ? ? 912 257 798 824 713 178 - ? 371
Total number of nests 330 300 146 235 57 271 217 235 86 - 107 135
Number of eggs ? ? ? 17254 5244 21187 18855 19595 3896 - 6450 10903
Hatchlings reaching the sea ? ? 3109 1611 3036 7539 5155 7397 ? - 3473 5439
Nest density (nest/km) ? ? ? 50 14 58.02 46.46 50.31 ? - 22.7 28.7
Fethiye
Total emergence - - - - - - - 240 439 888 235 291
Total number of nests - - - - - - - 118 158 191 88 95
Number of eggs - - - - - - - 8772 12926 15853 7656 6679
Hatchlings reaching the sea - - - - - - - 3337 5953 6991 3488 3671
Nest density (nest/km) - - - - - - - 14.75 19.75 23.9 11 11.9
Patara
Total emergence - - - - 128 - 163 294 75 - ? 205
Total number of nests - - - - 58 - 52 85 33 - 35 52
Number of eggs - - - - 5150 - 2920 7315 1293 - 2629 3769
Hatchlings reaching the sea - - - - ? - 1086 2030 ? - 1068 1638
Nest density (nest/km) - - - - 9.7 - 7.28 12.69 ? - ? 7.42
Belek
Total emergence - - - - - - - - 259 - ? 389
Total number of nests - - - - - - - - 68 - 153 168
Number of eggs - - - - - - - - 1065 - 10486 10988
Hatchlings reaching the sea - - - - - - - - ? - 6295 7082
Nest density (nest/km) - - - - - - - - ? - ? ?
Kizilot
Total emergence - - - - 299 - - - 195 - 427 303
Total number of nests - - - - 146 - - - 50 - 125 108
Number of eggs - - - - 11680 - - - 3029 - 9625 6243
Hatchlings reaching the sea - - - - ? - - - ? - 5406 3966
Nest density (nest/km) - - - - ? - - - ? - 27.7 24
TABLE 2. The data on the loggerhead turtles recorded annually at five different beaches of south-western Turkey. Letters indicate
the references considered. A, Geldiay et al., 1982; B, Groombridge, 1994; C, Baran et al., 1997; D, Erk’akan, 1993; E, Baran et al.,
1992; F, Canbolat, 1996; G, Yerli & Demirayak, 1996; H, Baran et al., 1996; I, Ilgaz, 1998; J, Türkozan & Baran, 1996; K, Baran &
Türkozan, 1996; L, Türkozan, 2000; M, Baran, 1993a; N, Taskin, 1998; O, Sak, 1998; P, Kaska, 1993.
for four breeding seasons: 1990, 1994, 1996 and 1997 (Ta-
ble 2). A total of 429 nests was recorded, with a mean of
107. The number of nests per season ranged from 50 to
146. Approximately 17-49 loggerhead turtles nest annu-
ally on the beach. During the years 1994 to 1997, a total
of 1129 eggs was destroyed. Of these, 657 were predated
by foxes (58.2%), 209 by coleopteran larvae (18.5%) and
193 by dogs (17.1%). Thirty-six eggs (3.2%) were taken
by a researcher for a sex determination study. Thirty-
four eggs (3.0%) were accidentally destroyed by
workers whilst using a metal rod to detect the nest sites.
Sixty-seven hatchlings were destroyed on the beach:
fox and bird predation accounted for 37 (55.2%) and
three (4.5%), respectively. Strong sunlight and dehydra-
tion caused 19 hatchlings (28.4%) to die. Dogs
destroyed eight hatchlings (11.9%).
The percentage of nesting success ranged from
29.7% to 32.4 %, whereas hatching success varied from
62.4 % to 63.5%. The percentage of hatchlings reaching
the sea ranged from 90% to 97.1%.
DISCUSSION
Taking into consideration all loggerhead turtle nest-
ing activity (Table 1), the five major nesting areas
described in this study account for 44%-46% of all
loggerhead nesting activity in Turkey. The overall nest-
ing activity on the 20 beaches used by loggerheads
revealed the fact that approximately 221-664 loggerhead
females visit the Turkish coasts. Groombridge (1994)
estimated a minimum of 1650 nests for the1988 season,
assuming 550 females nested. Data in Geldiay et al.
(1982) and Geldiay (1984) suggest that around 1000
O. TÜRKOZAN ET AL.30
Caretta caretta nested per season. Yerli and Demirayak
(1996) recorded a total of 884 loggerhead turtle nests for
the beaches of Turkey. The five major nesting areas con-
sidered here may hold 296-920 nests per season. This
means that approximately 99-307 loggerhead turtles nest
annually on these beaches
The results show that Dalyan beach has the highest
number of nests. According to Groombridge (1994), it is
unclear to what extent the eastern turtle beaches are
used by loggerheads. It is seen here that the green turtle
nesting sites are also used by loggerheads, with 1 to 23
nests per season. The mean number of nests varied be-
tween 53 and 193 on the south-western beaches of
Turkey. We are of the opinion that these values do not
fully reflect the capacity of the beaches. However, if we
consider the study periods, lengths and sections of the
beaches, these numbers reflect at least the minimum ca-
pacity of the five beaches. These data also highlight the
importance of the Turkish nesting sites, with
Margaritoulis (2000) estimating the overall number of
loggerhead nests in Greece as 2355-5287 per year.
Broderick & Godley (1996) recorded a total of 1347
loggerhead turtle nests in Northern Cyprus between
1992 and 1995, estimating that 22-173 loggerhead turtles
nest on these beaches per season.
Of the 23 997 eggs destroyed on the beaches, it is ob-
vious that canid predation was the main problem, with
some 22 232 eggs (93% of eggs predated) destroyed ei-
ther by foxes or dogs. It is well known that land-based
predators, including mammals, have less impact on
hatchlings than on eggs (Hopkins et al., 1979, Fowler,
1978). A total of 7399 hatchlings was destroyed on the
beaches. Light pollution caused the disorientation and
loss of 3135 hatchlings (42%). Crabs destroyed 2184
hatchlings (29.5%), whereas foxes destroyed 1462
(19.7%). These results represent only the general pat-
tern of the fate of loggerhead hatchlings. If we take the
beaches separately into consideration, crab predation
had the most effect on the hatchlings of the Dalyan and
Patara beaches, whereas fox predation was most harmful
on the Fethiye and Kizilot beaches. Light-pollution was
the main problem for the Belek beach, resulting in disori-
entation.
It is worth comparing these results with those for
other loggerhead nesting sites in the Mediterranean: ter-
restrial predators such as red foxes (Vulpes vulpes), feral
and domestic dogs, ghost crabs (Ocypoda cursor), and
scavenging birds (hooded crows, Corvus corone
cornix, and magpies, Pica pica) were recorded in North-
ern Cyprus (Broderick & Godley, 1996). Of the 48.4%
predation given by Margaritoulis (1988), red fox (Vulpes
vulpes) and stray dogs were the primary predators in
Kiparissia Bay, Greece. He claimed that exposed eggs
attracted other mammals (rats and martens) and birds. A
total of 34 loggerhead turtle nests was recorded on the
northern Mediterranean coast of Israel (Silberstein &
Dmi’el, 1991). They stated that a sharp decline in the
number and density of loggerhead sea turtle nests in
NESTING OF LOGGERHEAD TURTLES IN TURKEY
TABLE 3. The effects of various predators on eggs and hatchlings of loggerhead turtles at five beaches considered (* metal rod, **
34 by metal rod and 36 taken for sex determination study).
Dalyan Fethiye Patara Belek Kizilot
Eggs Total number 17584 2091 2547 616 1129
Fox 17385 1515 1783 - 657
Crab 119 - 207 - -
Fox & Crab - - 586 - -
Fox or dog - - - 616 -
Feral dog - 83 - - 193
Bird - - 1 - -
Coleopteran larva - 370 - - 209
Human activity - 86 - - -
Plant root - 1 - - -
Other - 36* - - 70**
Hatchlings
Total number 2833 743 460 3276 67
Fox 908 405 60 - 37
Crab 1703 14 378 89 -
Feral dog - 52 - - 8
Bird 23 93 1 - 3
Car -6---
Strong sunlight 199 173 21 52 19
Light pollution - - - 3135 -
Other - - - - -
31
Israel was attributable to both regional and local proc-
esses.
A few loggerhead turtles still lay eggs at Canigli
beach, which is much visited by tourists at Lampedusa,
Italy (Gramentz, 1989). He stated that the black rat, Rat-
tus rattus, was found to be the main predator, besides
humans, on the beach. The number of loggerheads killed
annually was estimated at 150-300 in Lampedusa and
500-600 in Malta.
Kasparek (1995) surveyed the entire Syrian Mediter-
ranean coast (193 km) for marine turtle nesting in 1991
and found significant nesting sites between Latakia and
Jablah. He quoted 10 tracks/km theoretically in Syria and
attributed most of them to the loggerhead turtle.
Although we have described patterns of abundance
and threats at these five sites, monitoring of marine tur-
tle nesting on the south-west Mediterranean coast of
Turkey has not been consistent and uninterrupted. Thus,
before setting up predation management programs
(hunting, trapping, transplantation, offshore-releasing
hatcheries etc.), longer-term studies are recommended.
Of the five beaches, Dalyan is the site on which studies
and observations were most frequent. Despite the insuf-
ficient data from the five beaches considered in this
survey, it is obvious that natural predation greatly re-
duces hatchling production of the loggerhead turtle.
ACKNOWLEDGMENT
We are greatly indebted to Brendan Godley (Marine
Turtle Research Group, School of Biological Sciences,
University of Wales, UK), who kindly helped improve
the English of the manuscript.
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Accepted: 23.4.02
33
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Conservation plans often struggle to account for connectivity in spatial prioritization approaches for the protection of migratory species. Protection of such species is challenging because their movements may be uncertain and variable, span vast distances, cross international borders and traverse land and sea habitats. Often we are faced with small samples of information from various sources and the collection of additional data can be costly and time-consuming. Therefore it is important to evaluate what degree of spatial information provides sufficient results for directing management actions. Here we develop and evaluate an approach that incorporates habitat and movement information to advance the conservation of migratory species. We test our approach using information on threatened loggerhead sea turtles (Caretta caretta) in the Mediterranean.
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