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The yellow spotted mountain newt (Neurergus derjugini) is a critically endangered species restricted to fragmented habitats in highland streams of the middle Zagros Mountain in Iran and Iraq. We examined the species phylogeography by investigating sequences of a mitochondrial fragment of the ND2 gene for 77 individuals from 15 locations throughout the species known distribution. We found relatively high haplotype diversity (0.82 ± 0.025) but low nucleotide diversity (0.0038 ± 0.00022) across all populations. Phylogenetic trees supported monophyly, and the segregation of haplotypes was concordant with the haplotype network. We found a significant correlation between geographical and genetic distances among populations (r = 0.54, P ˂ 0.01), suggesting restricted gene flow. Molecular dating suggested that haplogroups diverged during the early or middle Pleistocene. Bayesian skyline plot provided evidence for an expansion of populations during the Pleistocene-Holocene transition period. Taken together, isolation by distance due to low dispersal capability, habitat fragmentation, and historical factors have shaped the current population structure of N. derjugini.

Captive breeding and reintroduction programs are important conservation tools and are used for increasing the number of plant and animal species worldwide.  The endemic Kaiser’s Mountain Newt Neurergus kaiseri is listed as Vulnerable on the Red List by the International Union for Conservation of Nature (IUCN) and is amended to Appendix I of the Convention of International Trade on Endangered Species (CITES).  In the present study, in order to learn about the survival ability of captive-born newts of N. kaiseri, we conducted a trial translocation of 15 two-year-old captive-born N. kaiseri into the highland stream in Sartakht Village, western Iran.  The survival rate of these newts were determined in two stages, involving early acclimatization in mesh bags and direct release in a highland brook.  In 12 surveys to the translocation site, a total of 86 individuals were identified during spring and summer.  The average survival rate during the acclimatizing phase was 98 ± 0.04 %, while an average survival rate of 12 ± 0.04 % was obtained when the newts were released in the brook.  Applying an average diurnal detection probability obtained for the Yellow Spotted Mountain Newt Neurergus derjugini, the overall survival rate in September when newts began the autumn withdrawal was 13%.  These findings demonstrate that captive-born N. kaiseri released into the wild in controlled conditions can survive during spring and summer and provide information for future reintroduction plan of this species.

Comparing the predatory impact of captive-bred and free-living yellow spotted mountain newt (Neurergus microspilotus) on the larval green toad (Bufotes variabilis). Captive breeding of endangered species is an important conservation tool, but it is not clear how long-term captive breeding can influence fitness attributes such as predatory ability. We experimentally investigated the predatory impact of adult captive-bred newts (CBN) and adult free-living newts (FLN) on the survival and growth of larval green toad (B. variabilis) in four predator density treatments containing none, one, two, or three newts. FLNs performed a rapid density-dependent predation, yielding average survival rates of tadpoles in no, low, medium, and high densities to 81 %, 74 %, 60 % and 17 %, respectively. CBNs had an average lower predation rate on B. variabilis tadpoles with a decrease in survival rate of tadpoles to 83 %, 81 %, 82 % and 77 % for 0, 1, 2 and 3 predator treatments, respectively. However, contrary to FLNs, they exhibited a significant increase in predation rate with time from 0.37 to 0.60 tadpoles per day. In addition, the growth rate of tadpoles reared with predators for the FLN group was significantly higher than the growth rate of tadpoles reared in control containers without the predator. In conclusion, our findings suggest that exposing captive-born adult yellow spotted mountain newts to their potential prey enriches the environment, and may be a useful approach in the development of more efficient captive breeding and reintroduction programs for this highly endangered amphibian. ResumenUna comparación de la capacidad de depredación de los individuos nacidos en cautividad y en libertad del tritón del Kurdistán (Neurergus micropillotus) sobre larvas de sapo verde (Bufotes variabilis). La cría en cautividad de especies amenazadas es un práctica importante en la conservación, pero no está claro si los programas de cría en cautividad a largo plazo pueden afectar a determinados atributos fundamentales de la eficacia biológica de las especies como la capacidad de depredación. En el presente estudio se estudian experimentalmente los efectos de la capacidad de depredación de tritones del Kurdistán adultos nacidos en cautividad (CBN) y de individuos obtenidos directamente de la naturaleza (FLN) en la supervivencia y el crecimiento de renacuajos de sapo verde mantenidos en cuatro tratamientos de densidad de depredadores, que contenían cero, uno, dos y tres tritones. El grupo de tritones FLN mostró una tasa de depredación rápida dependiente de la densidad de depredadores que conllevó que las tasas de supervivencia de los renacuajos en las densidades de control, baja, media y alta fueran, respectivamente, del 81 %, el 74 %, el 60 % y el 17 %. El grupo CBN tuvo una menor tasa media de depredación sobre los renacuajos de B. variabilis, cuya tasa de supervivencia disminuyó hasta el 83 %, el 81 %, el 82 % y el 77 % para los tratamientos con cero, uno, dos y tres tritones, respectivamente. Sin embargo, a diferencia del grupo FLN, est...