Testudo graeca is an endangered species of tortoise that inhabits Mediterranean areas of Africa, Asia, and Europe. Western populations are found on both sides of the Straits of Gibraltar. The effects of geographical isolation on genetic divergence were assessed by the sequence analysis of two mitochondrial DNA regions of the 12S rRNA and cytochrome b genes. Four different haplotypes were identified. A single haplotype was shared by all Spanish and some east Moroccan specimens. Two haplotypes were unique to the west Moroccan T. graeca populations and allowed the clear discrimination between individual specimens found west of the Moulouya River. Phylogenetic analysis based on the estimation of nucleotide sequence distances of the haplotypes suggests an African origin for the Spanish populations and a subspecies status for the west Moroccan pool.

The occurrence of classical (polybrominated diphenyl ethers, PBDEs) and emerging FRs (dechloranes, hexabromobenzene (HBB), pentabromoethyl benzene (PBEB) and decabromodiphenyl ethane (DBDPE)) in unborn eggs of 14 different species from Doñana Natural Space and surrounding areas was studied. PBDEs, Dec-602, Dec-603 and DP were detected in all the species, whereas HBB, PBEB, DBDPE and Dec-604 were not detected in any sample. ΣPBDE and ΣDechlorane levels ranged from 1.40 to 90.7, and from 0.77 to 260 ng/g lw, respectively. BDE-209 was the most abundant BDE congener in almost all the species, whereas Dec-602 was the predominant among dechloranes. In general, levels of PBDEs and dechloranes were similar and even higher for dechloranes, probably indicating the increasing use of dechloranes as a result of legal restrictions on PBDEs. In both cases, the most contaminated specie was the white stork. Using stable isotope characterization, differences among species and possible biomagnification processes were also evaluated. PBDE levels increased as the trophic position increased, showing biomagnification capacity. The same behavior was observed for Dec-602 and Dec-603; however, DP levels were not linearly correlated with trophic level. These results show that more attention should be given to emerging FRs such as dechloranes since they show similar environmental behavior as PBDEs.

Reproduction in female spur-thighed tortoises (Testudo graeca) in a population from southwestern Spain was studied by X-radiography of thread-trailed and radio-tagged individuals. Most females reproduce every year, laying one to four clutches from April to June with internesting intervals ranging from 21 to 29 days. Clutch size varied from 1 to 7 eggs and averaged 3.5 eggs. Carapace length and mass of females were positively correlated with the starting date and duration of the nesting season, while age was not correlated with any reproductive variable. Eggs averaged 33.87 × 27.97 mm in dimensions and 14.4 g in mass. Female mobility increased shortly before or after nesting, which resulted in wide dispersal of the various nests laid by an individual female.

The spur-thighed tortoise (Testudo graeca) is a terrestrial species in which multiple mating is frequently observed. We assessed the probability of multiple paternity in clutches (n = 15) laid by eight females, including successive clutches. Paternity was determined by microsatellite analyses at three loci. A large number of alleles per locus (n = 15–22) provided high probabilities of detecting multiple paternity, particularly at all loci combined (P = 0.989). Multiple paternity was found in 20% of the clutches in which offspring displayed more than two paternal alleles. However, this frequency may have been underestimated, given the small clutch sizes and the few loci used. Also, T. graeca is able to store sperm from single or multiple matings and can use it to fertilize subsequent clutches of eggs, as indicated by the fact that the second clutch of a captive female was sired by a different male and that clutches of another female were multiply sired by the same males. These results confirm that multiple paternity exists in T. graeca and that sperm storage in this species may be an important reproductive strategy to fertilize multiple clutches per year.

We assessed the dynamics of a population of spur-lhighcd tortoises, Testudo graeea. placed under long-term protection from human interference. We estimated demographic parameters and constructed vertical lite tables based on age structures for two different study periods separated by a 12-yr interval. Average age at maturity was 6.9 yr for males and 8.5 yr for females. Clutch size varied with female size, but tended to be constant among years. Average annual female fecundity over 9 yr was 8.4 eggs and decreased significantly in years of high rainfall. Females seemed to reproduce yearly, but with a constantly low output, probabiy maximising both their long-term reproductive potential and Ihc probability of producing offspring during favourable years for hatchling survival. Adult survival was high and constant between periods. Juvenile survivorship from egg to 6 yr and recruitment into the 5-8-yr-old cohorts were significantly higher in the second period. Life tables indicated a predominantly negative demographic trend for the first period, with an average population increase rate of 0.977. and an overall positive tendency for the second period, with an average increase rate of 1,091, These figures suggest that the population experienced a variation that was closer to the maximum estimates for the tirst period, mediated mainly by an increase in juvenile recruitment. The data indicate that, besides high adult survival rates, occasional high juvenile recruitment bouts may have an important regulatory effect on the population dynamics of Testudo graeea.

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Activity, mobility, growth rates, and space use of 48 hatchling spur-thighed tortoises, Testudo graeca, were monitored over a period of 8 months, from emergence from the nest in September until May. Individuals were followed by means of thread trailing and radio tracking. Overall average distance moved was 4.42 m/day and average home-range size was 13.7 m2. Hatchlings were active from emergence until mid-December, exhibited discontinuous hibernation until mid-February, and reached highest activity and mobility values in April–May. Overall, mobility varied significantly with daily solar radiation values and maximum temperature, and was significantly dependent on body condition in winter. Body size and mass had no influence on individual performance, and a significant proportion of variance among individuals remained unexplained. Little growth occurred in autumn and body condition decreased steadily, increasing only from February onwards. Growth rates increased in March–April. No individual differences in growth rates were detected, initial body size being the main determinant of body size after 8 months.