Susceptibility to acidification of groundwater-dependent wetlands affected by water level declines, and potential risk to an early-breeding amphibian species.

Eggs of the Western spadefoot toad (Pelobates cultripes) reached a 100% mortality in all 29 clutches deposited at a pH below 5.0 in a temporary pond of the Doñana National Park (SW Spain) throughout the wet season of 2006-2007. A similar trend was detected in a neighbouring pond. The proximity of these two ponds to a groundwater pumping area (<1.5km), prompted us to elucidate the possible links between the reduction in pond hydroperiod over past decades (1989-2008) and the decrease of groundwater pH-buffering capacity. The average hydroperiod had decreased by 4months since 1998-99 in the pond where the extensive egg mortality had occurred. The total alkalinity, and the Mg(2+)concentration had also significantly declined in the shallow water-table since 1998-99, from an average of 8.56 to 0.32meql(-1), and of 3.57 to 1.15meql(-1), respectively. This decline of the shallow groundwater buffering capacity could turn this pond more susceptible to the inorganic acidity associated with pyrite oxidation as the sediment S content was often above 0.03%. The initial ratio of S/Ca+Mg in the summer dry sediment was a good predictor of pore-water pH on re-wetting after desiccation (r(2)=0.802, p<0.01). Therefore, this ratio can give some anticipation to mitigate the impact of acidity on toad hatching before these temporary ponds are reflooded on the next wet season. Our results suggest that the long-term damage to pond water levels can trigger a potential risk of soil acidification in the presence of iron-sulphide minerals.

Helminth communities of the exotic introduced turtle, Trachemys scripta elegans in southwestern Spain: Transmission from native turtles.

We report the prevalence and diversity of helminth parasites found in native turtles Mauremys leprosa and Emys orbicularis from three localities in southwestern Spain and we describe the helminth communities of exotic turtles Trachemys scripta elegans coexisting in the wild with both native turtle species. Five nematodes species were identified, of which Serpinema microcephalus was the only species common between two localities, although infection parameters were different between them. This is the first report of cross transmission of S. microcephalus and Falcaustra donanaensis from native to exotic turtles and the first report of genus Physaloptera in turtles of the Palearctic Region. Continuous releasing of exotic pet turtles in wildlife ecosystems increases the risk of parasite introductions and, consequently, potential transmission to native species, and highlights the impending need for regulation of pet turtle trade in Europe.

Salmonella in free-living exotic and native turtles and in pet exotic turtles from SW Spain.

We screened 78 native and 94 exotic turtles from natural ponds and 39 exotic pet turtles for presence of Salmonella, resulting with infection rates of 6.61%, 6.4%, and 5.1%, respectively. Concurrent shedding of multiple serotypes of the bacteria was only detected in one pet turtle. Eleven isolates were obtained in free-living turtles, including serotypes commonly found in reptiles and also the serotype Typhimurium, which is commonly related to human infections. In pet turtles, the five serotypes isolated were different to those isolated in free-living turtles and had been reported to cause reptile-associated salmonellosis in humans. These results confirm the risk of transmission of Salmonella from free-living and pet turtles to humans, demanding the necessity of regulation of pet turtle trade in Europe.

PCB, DDT, arsenic, and heavy metal (Cd, Cu, Pb, and Zn) concentrations in chameleon (Chamaeleo chamaeleon) eggs from Southwest Spain.

This work presents the concentrations of twenty PCB congeners, p,p'-DDT, and its two main metabolites, p,p'-DDE, p,p'-TDE, As, Cd, Cu, Pb, and Zn found in common chameleon eggs from nine different nests located in Southwest Spain. Of the heavy metals and arsenic, Zn and Cu exhibited the highest concentrations in egg contents (ranging from 10100 to 12950 and from 567 to 706 ng g(-1) wet weight basis [w.w.], respectively) and eggshells (ranging from 5605 to 13290 ng g(-1)w.w. for Zn and from 1487 to 4361 ng g(-1)w.w. for Cu). Total PCB concentrations in egg contents ranged from 32 to 52 ng g(-1)w.w. and were higher than total dichlorodiphenylethanes concentrations (ranging from 0.67 to 1.9 ng g(-1)w.w., calculated as the sum of p,p'-DDT plus p,p'-DDE and p,p'-TDE). Comparison of the data from the present study with the data from a study conducted in 1997 revealed a large decrease in Pb concentration and a twofold increase in PCB concentrations. Taking into account all the pollutants investigated, the contamination level found in common chameleon eggs from Southwest Spain was generally lower than has been reported in the literature for eggs of different reptile species. However, it should be borne in mind that most of the data found in the literature refer to highly polluted areas.

Salmonella in free living terrestrial and aquatic turtles.

Detection of Salmonella in pet turtles has been the focus of extensive research, but its incidence in free living turtles is not well known. The aim of this study was to evaluate the incidence of Salmonella in terrestrial and aquatic species of chelonians inhabiting a National Park in southwestern Spain. Individuals of the terrestrial tortoise Testudo graeca (n = 16) and the aquatic turtles Emys orbicularis (n = 26) and Mauremys leprosa (n = 50) were investigated. Maximum incidence of Salmonella was recorded in the terrestrial species (100%). In contrast, the incidence of infected animals was low in the aquatic species, 12% in M. leprosa and 15.4% in E. orbicularis. Five serotypes of Salmonella belonging to subspecies enterica (I) and salamae (II) were identified. All serotypes were found in the terrestrial species, and three in the aquatic ones, suggesting that wild terrestrial chelonians are important reservoirs of Salmonella in our study area. Cloacal transmission during mating is the most probable mode of transmission among individuals.

Hematology and clinical chemistry in dystocic and healthy post-reproductive female chameleons.

Prevalence of egg-laying disorders and hematology and blood chemical parameters were analyzed in free-ranging common chameleons (Chamaeleo chamaeleon) from southern Spain. During four reproductive seasons oviposition failures occurred only during dry years. Egg binding appeared to be an important cause of mortality. Oviductal eggs of dystocic females were longer and wider than those of females with normal oviposition. Blood cell counts, white blood cell differentials, hematocrit, and concentration of hemoglobin, total plasma protein, glucose, uric acid, aspartate aminotransferase, and creatinine phosphokinase in blood were determined for eight apparently healthy post-reproductive females and considered as reference values. These chameleons differed from other reptiles in high concentrations of glucose in blood, averaging 362 mg/dl, and in high numbers of heterophils. Females with dystocia differed from reference values in an increase in monocytes and in the high concentrations of aspartate aminotransferase probably associated with tissue trauma.

Mitochondrial DNA haplotyping of Testudo graeca on both continental sides of the Straits of Gibraltar.

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.