Do helminths increase the vulnerability of released pheasants to fox predation?

The success of ring-necked pheasant (Phasianus colchicus) restocking in Asturias, northern Spain was assessed, and the role of parasites and predators in the mortality of released birds was studied. The experimental release of 56 radio-tagged pheasants showed that 98% of birds died within 12 days. As soon as 72 h after release, 67.5% of males and 55.0% of females were found dead. Foxes (Vulpes vulpes) killed 63% of the birds. The survival of those birds killed by foxes was lower than for birds which died due to other causes, and pheasants depositing eggs of the nematode Eucoleus contortus (Creplin, 1839) survived less than those apparently non-parasitized. No impact of the parasite on the pheasants' condition was found, but foxes preyed upon parasitized birds more than expected by random. The results suggest that: (i) the current pheasant releases in this area are unsuccessful and need to be improved; (ii) this is mainly due to intense predation by red foxes; and (iii) parasites could have some influence on the predation of released birds by foxes. However, the way parasites affect pheasant vulnerability remains unclear.This is a contribution to the joint project CSIC/Principado de Asturias.Peer reviewe

Effects of a fiber-rich diet on physiology and survival of farm-reared red-legged partridges (Alectoris rufa)

The sudden shift from a commercial energy-rich, fiber-poor diet to natural food is assumed as one of the causes of the low success of gamebird restocking. We fed farmed red-legged partridge (Alectoris rufa) chicks with a diet rich in fiber from their first month of life to the time of their release to assess the possible effects on morphometric characteristics and plasma biochemistry and whether those effects enhance survival after release into the wild. At the time of release, treated partridges showed heavier gizzards and bursas of Fabricius and longer small intestines than control birds fed commercial feed. Treated birds had also smaller pectoral muscles, lighter spleens and lower plasma levels of proteins, glucose, cholesterol and triglycerides. After release and radiotracking in a hunting area, we found no differences in the survival between both groups. Survival at the end of the study (day 39) was 58.3±14.2% for the control group and 24.2±13.8% for the treated group. The fiber-rich diet seems to have important effects on the physiology of the red-legged partridge, not always taken into account in previous studies.This is a contribution to FEDER-UE IF 1FD1997-2299 and a project by CSIC-Junta de Andalucı́a.Peer reviewe

Self-injury and capture myopathy in net-captured juvenile red-legged partridge with necklace radiotags

Adverse effects of radiotransmitters and handling are major concerns during radiotracking studies, especially in avian species. Fourteen out of 46 (30.4%) juvenile red-legged partridge (Alectoris rufa) trapped using hand-held nets and marked with necklace radiotags during a study in southern Spain died within a few hours after capture. We studied the affected birds and compared data from postmortem examination, blood chemistry, biometry, and meteorology on capture days to identify risk factors related to the deaths. The affected partridge had high creatine kinase plasma levels. Postmortem examination confirmed that the deaths had been due to self-injury, capture myopathy (CM), or both. Distribution of lesions indicated that struggling with the transmitter could have exacerbated CM caused by trapping and handling. There was no effect due to bird size or weight, but deaths were related to capture days with lower mean temperatures and higher humidity. The consideration of combined risk factors such as climate, capture method, and radiotag type may deserve more attention regarding capture and radiotagging techniques, especially in juvenile partridge.This study was supported by project 1FD1997-2299 and the Junta de Andalucía. M. Castillo, M. Muñoz, and many colleagues helped with the fieldwork. Comments from the referees helped to greatly improve the manuscript.Peer Reviewe

Dehydrogenation of formic acid using iridium-NSi species as catalyst precursors

Using a low loading of the iridium(III) complexes [Ir(CF3SO3)(κ2-NSiiPr)2] (1) (NSiiPr = (4-methylpyridin-2-yloxy)diisopropylsilyl) and [{Ir(κ2-NSiMe)2}2(μ-CF3SO3)2] (2) (NSiMe = (4-methylpyridin-2-yloxy)dimethylsilyl) in the presence of Et3N, it has been possible to achieve the solventless selective dehydrogenation of formic acid. The best catalytic performance (TOF5 min ≈ 2900 h−1) has been achieved with 2 (0.1 mol%) and Et3N (40 mol% to FA) at 373 K. Kinetic studies at variable temperatures show that the activation energy of the 2-catalyzed process at 353 K is 22.8 ± 0.8 kcal mol−1. KIE values of 1.33, 2.86, and 3.33 were obtained for the 2-catalyzed dehydrogenation of HCOOD, DCOOH, and DCOOD, respectively, in the presence of 10 mol% of Et3N at 353 K. These data show that the activation of the C–H bond of FA is the rate-determining step of the process. A DFT mechanistic study for the catalytic cycle involving hydride abstraction from the formate anion by the metal, assisted by a molecule of formic acid, and heterolytic H2 formation has been performed. Moreover, the presence of Ir-formate intermediates was identified by means of NMR studies of the catalytic reactions in thf-d8 at 323 K. In all the cases, the decomposition of the catalyst to give unactive crystalline iridium NPs was observed.The financial support from projects PGC2018-099383-B-I00 (MCIU/AEI/FEDER, UE), RTI2018-099136-A-I00 (MCIU/AEI/FEDER, UE), CSIC project 202080I024 and DGA/FSE project E42_20R is gratefully acknowledged. A. U. thankfully acknowledges the Spanish MECD for a FPU fellowship (FPU 2017/05417).Peer reviewe

IAA : Información y actualidad astronómica (43)

Sumario : CALIFA: una visión panorámica de las galaxias del universo local.-- REMS: la estación medioambiental española en Marte.-- CIENCIA EN HISTORIAS...Paris Pişmiş.-- DECONSTRUCCIÓN Y otros ENSAYOS. ¿Ondas gravitatorias primordiales?.-- EL “MOBY DICK” DE... Mayra Osorio (IAA-CSIC).-- ACTUALIDAD.-- SALA LIMPIA.-- CIENCIA: PILARES E INCERTIDUMBRES. Nebulosas planetarias.N

Improving decision-making for sustainable hunting: regulatory mechanisms of hunting pressure in red-legged partridge

Knowledge about how hunting pressure is determined, and the relative efficacy of different mechanisms to regulate harvest, can help to improve the managers’ decision-making process. We developed a general framework about the decision-making process that regulates red-legged partridge (Alectoris rufa) hunting pressure in central Spain based on information from a focus group and individual interviews with game managers. We also used available information to compare the efficiency of different tools thus improving some decision steps. We evaluated the cost-effectiveness of different population monitoring methods as a way to reduce uncertainty on partridge availability to hunters. Additionally, we investigated the relationship between annual harvest and various regulatory mechanisms of partridge hunting pressure used in the study area to identify the most potentially useful one to limit annual take-off. Game managers usually set hunting pressure after a qualitative assessment on population abundance prior to the hunting season, but this decision was frequently modified during the course of the hunting season according to variations in catch or perceived abundance at that time. Our results showed that kilometric abundance indices (counting partridges from cars along line transects) was a simple cost-efficient and reliable estimate of partridge density (estimated by Distance sampling). A variety of regulatory mechanisms were used by managers. The variables that most affected annual harvest (in addition to partridge abundance) were the number of driven-shooting days, and hunter density in walked-up hunting days, suggesting that their adjustment will be the most efficient regulatory mechanisms. We conclude that adequate monitoring on population abundance should be a critical step for managers’ decision-making, and that a better understanding of the relative value of regulatory mechanisms, combining social and ecological approaches, would help improving our understanding of any human-mediated system, thus leading to better management recommendations.Work was supported by the European Commission (7th Framework Programme for R&D through project HUNT, 212160, FP7-ENV-2007-1); Consejería de Agricultura of JCCM; by the Ministerio de Ciencia y Tecnología (CGL2008-04282/BOS), and by CSIC (PIE 201330E105).Peer reviewe