Aspectos ecológicos de la anidación de Caiman crocodilus chiapasius (Bocourt, 1876) en la reserva de la biosfera La Encrucijada, México

Existen pocos estudios sobre el caimán de anteojos, Caiman crocodilus chiapasius, realizados en México. En el presente estudio evaluamos las características clave de la ecología reproductiva del caimán en México. Se realizó una búsqueda de nidos entre abril y septiembre de 2014, y se observó que la construcción de los mismos tiene lugar en junio y las eclosiones, en septiembre y octubre. La fase lunar influye en la anidación. Asimismo, la altura del nido, la distancia al árbol más cercano y la distancia desde el borde superior del nido al primer huevo están relacionadas con el éxito de eclosión y la temperatura de incubación.Ecological aspects of nesting in Caiman crocodilus chiapasius (Bocourt 1876) in La Encrucijada Biosphere Reserve, Mexico Studies on caiman, Caiman crocodilus chiapasius, in Mexico are scarce. The present study was conducted to evaluate the key characteristics regarding the reproductive ecology of caiman in Mexico. We conducted nest searches from April to September 2014. We observed that nests were built in June and that hatching occurred in September and October. The phase of the moon had an effect on nesting events. The height of the nest, the distance to the nearest tree, and the distance from the top of the nest to the first egg were related to hatching success and incubation temperature.Existen pocos estudios sobre el caimán de anteojos, Caiman crocodilus chiapasius, realizados en México. En el presente estudio evaluamos las características clave de la ecología reproductiva del caimán en México. Se realizó una búsqueda de nidos entre abril y septiembre de 2014, y se observó que la construcción de los mismos tiene lugar en junio y las eclosiones, en septiembre y octubre. La fase lunar influye en la anidación. Asimismo, la altura del nido, la distancia al árbol más cercano y la distancia desde el borde superior del nido al primer huevo están relacionadas con el éxito de eclosión y la temperatura de incubación

Status of the light ion source developments at CEA/Saclay

ACC NIMInternational audienceSILHI (High Intensity Light Ion Source) is an ECR ion source producing high intensity proton ordeuteron beams at 95 keV. It is now installed in the IPHI site building, on the CEA/Saclay center. IPHI is a frontend demonstrator of high power accelerator. The source regularly delivers more than 130 mA protons in CWmode and already produced more than 170 mA deuterons in pulsed mode at nominal energy. The last beamcharacterisations, including emittance measurements, space charge compensation analysis and diagnosticimprovements, will be reported. Taking into account the SILHI experience, new developments are in progress tobuild and test a 5 mA deuteron source working in CW mode. This new source will also operate at 2.45 GHz andpermanent magnets will provide the magnetic configuration. This source, of which the design will be discussed,will have to fit in with the SPIRAL 2 accelerator developed at GANIL to produce Radioactive Ion Beams. TheH- test stand status is briefly presented here and detailed in companion papers.This work is partly supported by the European Commission under contract n°: HPRI-CT-2001-50021

Temporal variation in black-caiman-nest predation in varzea of central Brazilian amazonia

On the Amazon floodplain, the main predators of black caiman (Melanosuchus niger) eggs are jaguars (Panthera onca), tegu lizards (Tupinambis teguixim), capuchin monkeys (Sapajus macrocephalus) and humans (Homo sapiens). In this study, we investigated the relationship between predator attacks on nests and incubation period, and evaluated the influence of initial predation on subsequent predation in the Mamirauá Sustainable Development Reserve. We also evaluated the influence of presence of females near the nests and manipulation of nests on the occurrence of attacks. We compared results from data obtained with camera traps and vestiges left by predators on estimates of rates of predation by different predators. Egg predation was recorded in 32% of the 658 black caiman nests monitored during two years. Our results suggest that the probability of predation on black caiman eggs is relatively constant throughout the incubation period and that predation on eggs was lower when adults, presumably females, were present. Careful opening of nests and handling of eggs did not increase the number of attacks on black caiman nests. Nest opening by a predator appeared to increase the chances of a subsequent attack because most of the attacks on nests occurred soon after a predator first opened the nest. However, attacks by another species of predator do not appear to be necessary to initiate attacks by any other species of predator. Results based on camera traps and vestiges differed, but use of vestiges was adequate for identifying the principal predators on eggs in black caiman nests and, in many circumstances, the vestiges may be better for estimating predation by humans. In this study, opening nests and handling eggs did not increase the number of attacks on black caiman nests. © 2017 Torralvo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Validating local knowledge on camels: Colour phenotypes and genetic variation of dromedaries in the Nigeria-Niger corridor

AbstractThe traditional camel breeding concept of pastoralists in the Nigeria-Niger corridor favours certain dromedary colour phenotypes, which are associated with distinct economic and behavioural traits. With the increasing requirement of sustainable food sources in desert environments the economic interest in Nigerian dromedaries has also been growing. In this study we used mitochondrial and microsatellite data to understand if the observed colour phenotypes correspond to genetically distinct groups and whether these groups reflect the breeding concept of camel pastoralists in the Nigeria-Niger corridor. Our results showed that Nigerian dromedaries are composed of a homogenous gene pool with no specific clustering according to coat colour. Significant but low nuclear and mitochondrial differentiation was detected only between dark-brown and black-brown camels. In addition to little evidence for population structure, Nigerian dromedaries exhibited a high genetic diversity, which could be explained by continuous gene flow with other populations during the annual transhumant voyage embarked upon by pastoralists on both sides of the Nigeria-Niger corridor. In comparison to local pastoralists' knowledge, the molecular genetic data do not support a clear distinction into breeds (Ja, Kurri, and Kala) based on coat colour differences

Between introgression events and fragmentation, islands are the last refuge for the American crocodile in Caribbean Mexico.

International audienc

High mitochondrial differentiation levels between wild and domestic Bactrian camels: a basis for rapid detection of maternal hybridization

Hybridization between wild species and their domestic congeners often threatens the gene pool of the wild species. The last wild Bactrian camel (Camelus ferus) populations in Mongolia and China are examples of populations facing such a hybridization threat. To address this key issue in the conservation of wild camels, we analysed wild, hybrid and domestic Bactrian camels (Camelus bactrianus) originating from Mongolia, China and Austria. Through screening of an 804-base-pair mitochondrial fragment, we identified eight mitochondrial haplotypes and found high sequence divergence (1.9%) between C. ferus and C. bactrianus. On the basis of a mitochondrial DNA sequence fixed difference, we developed a diagnostic PCR restriction fragment length polymorphism (PCR-RFLP) assay to differentiate between wild and domestic camel samples. We applied the assay to 81 individuals and confirmed the origin of all samples including five hybrids with known maternal ancestry. The PCR-RFLP system was effective for both traditional (blood, skin) and non-invasive samples (faeces, hair), as well as for museum specimens. Our results demonstrate high levels of mitochondrial differentiation between wild and domestic Bactrian camels and that maternal hybridization can be detected by a rapid and reliable PCR-RFLP system

Development of a permanent magnet light ion source at CEA/Saclay

International audienceIn France, the Spiral 2 project dedicated to radioactive beam production is based on a 40 MeV continuous wave (cw) deuteron Linac. This installation will allow extending the variety of accelerated particles to very heavy elements. Such beams will open research domains for the GANIL facility. To inject the requested 5 mA deuteron beam into the Spiral 2 Linac, the performance of the high intensity light ion source (SILHI) allowed us to propose such an electron cyclotron resonance source. SILHI, developed at CEA/Saclay, regularly produces high intensity (over 100 mA) proton or deuteron beams through a $\Phi$ 9 mm aperture. So for this project, the main modifications of the source design concern the permanent magnets which provide the axial magnetic configuration and the $\Phi$ 3 mm aperture. The source produced its first beam (proton) in 2004. This article will report the beam characterization while the source produced $D^+$ beam with intensity as high as 7.0 mA. Recently, this permanent magnet source has been equipped with the $\Phi$ 9 mm plasma electrode. So high intensity proton beams reaching more than 100 mA are now extracted from this source