Eyup Başkale

SEA TURTLE NEST CONSERVATION TECHNIQUES ON SOUTHWESTERN BEACHES IN TURKEY

Loggerhead turtle nests at risk from tidal inundation and predation were either relocated, screened against predation, or fenced in areas of heavy human activity on Fethiye, Dalyan, and Dalaman beaches during the nesting seasons of 2000-2002. Relocation, screening, and fencing clearly increased the hatching success rate and provided effective protection of sea turtle nests against inundation and predation. The emergence pattern and sex ratios of hatchlings, incubation periods, and distances of nests from the water line were analyzed. Incubation temperatures leading to a high female-biased sex ratio were found on Dalyan Beach. Sand and nest temperatures of the relocated nests at the hatchery site influenced the sex ratios, as seen from histological sexing of dead hatchlings from both in situ and relocated nests.

Natural and anthropogenic factors affecting the nest-site selection of Loggerhead Turtles, Caretta caretta, on Dalaman-Sarıgerme beach in South-west Turkey.

Abstract The nesting activities of Loggerhead Turtles (Caretta caretta Stejneger, 1902) and anthropogenic factors affecting them were monitored over 7 years (2002–2008) on Dalaman-Sarıgerme beach, one of the main nesting grounds in Turkey. Out of the 2620 nesting emergences recorded during the entire study period, only 645 (24.6%) resulted in successful nesting, giving an annual mean number of nests of 92. The collective number of eggs in these nests numbered 50239, with 40079 (79.8%) of them producing hatchlings. Out of the total number of eggs laid, 8128 (16.2%) resulted in dead embryos and 2032 (4.0%) in unfertilized eggs. The mean incubation period averaged 49 days (range 40–67 days) and the mean clutch size was 79.0 (range 18–150 eggs). Turtle nests were more concentrated on the undeveloped parts of the beach than on developed parts. In the other sections, few emergences occurred and either no or few nests were recorded. In Section I, which contained hotels and water sports facilities, only a few non-nesting emergences were observed. Of the number of nests that were observed, 32% were laid in Section II, which contained recently built hotels, 60% were in Section III and 8% were in Section IV, the undeveloped portion containing beach rocks. There is very clear evidence that the Loggerhead Turtles are shifting their nesting sites to the undisturbed sites along the beach. The negative factors that seem to be affecting them include water sports, hotel lights and beach rocks. In order to protect sea turtles, there needs to be a better understanding of how effective beach protection can be established.

Population Size and Age Structure of Metamorphic and Pedomorphic Forms of Ommatotriton ophryticus (Berthold, 1846) in the Northwestern Black Sea Region of Turkey

Abstract Amphibians are in decline in many parts of the world. Understanding the population dynamics of amphibian species is an important prerequisite for developing effective conservation strategies. We used capture–mark–recapture and skeletochronological techniques to investigate population size, body size, and age structure of metamorphic and pedomorphic forms of Ommatotriton ophryticus between 2006 and 2009 in the northwestern Black Sea region of Turkey. Our findings showed that time-specific survival rate, constant capture probability, no temporary emigration, and time-specific population size were the most appropriate models for this population. According to the best model (Model 6), population size of metamorphic forms of O. ophryticus was estimated as 517 (95% confidence interval [CI] = 338–851) adults in 2006, 338 (95% CI = 282−421) adults in 2008, and 527 (95% CI = 443–646) adults in 2009. Average annual capture probability was estimated at 0.21, although average survival rate across years was 0.35. The mean body size and age structure of the pedomorphs and metamorphs was significantly different for both sexes. Also, body size of both forms of O. ophryticus showed positive significant correlations with age. In addition to this, both forms shared a common allometric slope of the snout–vent lengths vs. age, and older individuals had larger bodies. Moreover, age at first reproduction and longevity exhibited great differences between forms whereas the median age was 4 yr for each newt category, except for metamorphosed males, in which it was 5 yr. These results indicate that pedomorphs in this population show retardation of the somatic development and an earlier maturation.

Invertebrate infestation on eggs and hatchlings of the loggerhead turtle, Caretta caretta , in Dalaman, Turkey

The damage caused by some invertebrates to the eggs and hatchlings of loggerhead turtles, Caretta caretta, was investigated during the summer of 2002 on Dalaman beach, Turkey. The specimens, identified to family or genus levels, from nine families representing seven orders were recorded as infesting nests of loggerhead turtles. The heaviest impacts on loggerhead turtle nests was made by Pimelia sp. (Tenebrionidae, Coleoptera). Twenty-four (36.3%) out of 66 intact loggerhead hatched nests were affected by these larvae. Larval damage by Pimelia sp. was recorded in 188 (10.6%) out of 1773 eggs, but only in two (0.28%) hatchlings. The results show that fewer insects were in the nest the further from vegetation and therefore the relocation of nests from the waters edge to further inland close to vegetation may increase the infestation rate of the eggs.

Decline of the Levantine Frog, Pelophylax bedriagae Camerano, 1882, in the western Aegean Region of Turkey: changes in population size and implications for conservation (Amphibia: Ranidae).

Abstract We estimated the annual population size, survival rates and capture probabilities for two populations of the Levantine Frog, Pelophylax bedriagae, using a Capture-Mark-Recapture (CMR) non-invasive digital photographic identification technique in Karagöl Lake and Soğan-harımı Pond in the western Aegean Region of Turkey, and used POLLOCK’s methodology to assess population parameters. Time specific capture probability, time specific survival rate and no temporary emigration were found to be the best appropriate models for our data. Population sizes were estimated as 245 adults in 2006, 301 in 2007, 67 in 2008 and 54 in 2009. Annual capture probabilities were estimated on average as 0.161, and annual survival rates across years were on average 0.301. Soğanharımı Pond was destroyed for recreational purposes after the first year of our study. To determine the size of the population, which was depleted during the construction of the recreational facilities, we used a closed population model, and concluded that in total 54 adults disappeared. In addition, we determined the possible negative factors that affect the population size and survival rates of the Levantine Frog including habitat destruction and the introduction of Siluris glanis and Astacus leptodactylus into the freshwater body.

Reproductive ecology and body size-fecundity relationships of the Green Toad,Pseudepidalea viridis(Laurenti, 1768), in the Kocaçay Stream, İzmir, Turkey: (Amphibia: Anura)

Abstract We studied the breeding biology of the Green Toad, Pseudepidalea viridis (Laurenti, 1768), in the 2007–2008 breeding seasons at Kocaçay Stream. The breeding period began in early February and lasted approximately two months. The median of the breeding seasons was calculated as 5tMarch for the entire study period 2007–2008. The average clutch size was 14,594 eggs and this value was higher than in other conspecific populations from Denmark, Israel and Italy. Clutch size and clutch mass were significantly correlated with female body size, but single egg mass and egg diameter were not. A negative significant correlation was seen between clutch size and egg diameter.