Intensity of Territorial Marking Predicts Wolf Reproduction: Implications for Wolf Monitoring

BACKGROUND: The implementation of intensive and complex approaches to monitor large carnivores is resource demanding, restricted to endangered species, small populations, or small distribution ranges. Wolf monitoring over large spatial scales is difficult, but the management of such contentious species requires regular estimations of abundance to guide decision-makers. The integration of wolf marking behaviour with simple sign counts may offer a cost-effective alternative to monitor the status of wolf populations over large spatial scales. METHODOLOGY/PRINCIPAL FINDINGS: We used a multi-sampling approach, based on the collection of visual and scent wolf marks (faeces and ground scratching) and the assessment of wolf reproduction using howling and observation points, to test whether the intensity of marking behaviour around the pup-rearing period (summer-autumn) could reflect wolf reproduction. Between 1994 and 2007 we collected 1,964 wolf marks in a total of 1,877 km surveyed and we searched for the pups' presence (1,497 howling and 307 observations points) in 42 sampling sites with a regular presence of wolves (120 sampling sites/year). The number of wolf marks was ca. 3 times higher in sites with a confirmed presence of pups (20.3 vs. 7.2 marks). We found a significant relationship between the number of wolf marks (mean and maximum relative abundance index) and the probability of wolf reproduction. CONCLUSIONS/SIGNIFICANCE: This research establishes a real-time relationship between the intensity of wolf marking behaviour and wolf reproduction. We suggest a conservative cutting point of 0.60 for the probability of wolf reproduction to monitor wolves on a regional scale combined with the use of the mean relative abundance index of wolf marks in a given area. We show how the integration of wolf behaviour with simple sampling procedures permit rapid, real-time, and cost-effective assessments of the breeding status of wolf packs with substantial implications to monitor wolves at large spatial scales

Informe Optoel 2021

[No abstract available

Periodic Radio and H-alpha Emission from the L Dwarf Binary 2MASSW J0746425+200032: Exploring the Magnetic Field Topology and Radius of an L Dwarf

[Abridged] We present an 8.5-hour simultaneous radio, X-ray, UV, and optical observation of the L dwarf binary 2MASSW J0746+20. We detect strong radio emission, dominated by short-duration periodic pulses at 4.86 GHz with P=124.32+/-0.11 min. The stability of the pulse profiles and arrival times demonstrates that they are due to the rotational modulation of a B~1.7 kG magnetic field. A quiescent non-variable component is also detected, likely due to emission from a uniform large-scale field. The H-alpha emission exhibits identical periodicity, but unlike the radio pulses it varies sinusoidally and is offset by exactly 1/4 of a phase. The sinusoidal variations require chromospheric emission from a large-scale field structure, with the radio pulses likely emanating from the magnetic poles. While both light curves can be explained by a rotating mis-aligned magnetic field, the 1/4 phase lag rules out a symmetric dipole topology since it would result in a phase lag of 1/2 (poloidal field) or zero (toroidal field). We therefore conclude that either (i) the field is dominated by a quadrupole configuration, which can naturally explain the 1/4 phase lag; or (ii) the H-alpha and/or radio emission regions are not trivially aligned with the field. Regardless of the field topology, we use the measured period along with the known rotation velocity (vsini=27 km/s), and the binary orbital inclination (i=142 deg), to derive a radius for the primary star of 0.078+/-0.010 R_sun. This is the first measurement of the radius of an L dwarf, and along with a mass of 0.085+/-0.010 M_sun it provides a constraint on the mass-radius relation below 0.1 M_sun. We find that the radius is about 30% smaller than expected from theoretical models, even for an age of a few Gyr.Comment: Submitted to Ap

Frugivoría y dispersión de semillas por mamíferos carnívoros: rasgos funcionales

Muchas especies de mamíferos carnívoros (Orden Carnivora) consumen frutos carnosos, transportan semillas en sus tractos digestivos y las defecan sin dañarlas en condiciones apropiadas para la germinación. En este artículo, revisamos el conocimiento adquirido sobre este mutualismo en las últimas tres décadas, desde que tres trabajos pioneros revelaron la importancia de los carnívoros como dispersores de semillas en ecosistemas templados. Nos centramos en los rasgos funcionales de los carnívoros consumiendo frutos y diseminando semillas, haciendo especial énfasis en sus diferencias con las aves, el principal grupo de vertebrados frugívoros en ecosistemas templados. Los carnívoros no están sujetos a las restricciones fenológicas o morfológicas que típicamente limitan el consumo de determinados frutos en muchas especies de aves. Consumen preferentemente frutos cuyos atributos son compartidos con muchas especies de frutos cultivados por el hombre, lo que explica el consumo frecuente de éstos en paisajes antrópicos. Sus amplios requerimientos espaciales favorecen la dispersión de semillas a larga distancia, mientras que su generalismo en relación al hábitat favorece el flujo de semillas entre hábitats contrastados. De este modo, los carnívoros promueven la conectividad entre poblaciones vegetales y la colonización. Estas funciones ecológicas son clave para las comunidades vegetales nativas, especialmente en escenarios de cambios de uso de suelo. Sin embargo, estos patrones de dispersión de semillas pueden contribuir a la invasión de plantas exóticas. Aún ignoramos en gran medida el papel de los carnívoros en términos cuantitativos de la dispersión de semillas y las diferencias funcionales entre especies dentro del gremio. La integración de muestreos clásicos e innovadoras técnicas moleculares y de análisis espacial promete aportar conocimiento inédito en estas cuestiones[EN ] Many species of carnivorous mammals (Order Carnivora) consume fleshy fruits, transport seeds in their digestive tracts, and defecate them without damage in conditions that are suitable for germination. In this article, we review the state of the art on this mutualism in the past three decades, since three pioneering studies revealed the importance of carnivores as seed dispersers in temperate ecosystems. We focus on the functional traits of carnivores consuming fruits and disseminating seeds, with particular emphasis on their differences with birds, the main group of vertebrate frugivores in temperate ecosystems. Carnivores are not subject to the phenological or morphological constraints that typically limit the consumption of certain fruit species in many bird species. They preferably consume fruits whose traits are shared with many fruit species cultivated by man, which explains the frequent consumption of cultivated fruits in anthropogenic landscapes. The large spatial requirements of carnivores promote long-distance seed dispersal, while their habitat generalism promotes seed flows between contrasting habitats. Thus, carnivores promote connectivity between plant populations and colonization. These are key ecological functions for native plant communities, especially in scenarios of land-use changes. However, these seed dispersal patterns can contribute to the invasion of exotic plants. We still largely ignore the role of carnivores in quantitative terms of seed dispersal and the functional differences between species within the guild. Integrating traditional fieldwork and innovative molecular techniques and spatial analysis promises to provide unprecedented knowledge on these issuesPeer reviewe

Toward reliable population estimates of wolves by combining spatial capture-recapture models and non-invasive DNA monitoring

Decision-makers in wildlife policy require reliable population size estimates to justify interventions, to build acceptance and support in their decisions and, ultimately, to build trust in managing authorities. Traditional capture-recapture approaches present two main shortcomings, namely, the uncertainty in defining the effective sampling area, and the spatially-induced heterogeneity in encounter probabilities. These limitations are overcome using spatially explicit capture-recapture approaches (SCR). Using wolves as case study, and non-invasive DNA monitoring (faeces), we implemented a SCR with a Poisson observation model in a single survey to estimate wolf density and population size, and identify the locations of individual activity centres, in NW Iberia over 4,378 km. During the breeding period, posterior mean wolf density was 2.55 wolves/100 km (95%BCI = 1.87-3.51), and the posterior mean population size was 111.6 ± 18.8 wolves (95%BCI = 81.8-153.6). From simulation studies, addressing different scenarios of non-independence and spatial aggregation of individuals, we only found a slight underestimation in population size estimates, supporting the reliability of SCR for social species. The strategy used here (DNA monitoring combined with SCR) may be a cost-effective way to generate reliable population estimates for large carnivores at regional scales, especially for endangered species or populations under game management.J.V.L.B. was supported by a Ramon & Cajal research contract (RYC-2015-18932) from the Spanish Ministry of Economy, Industry and Competitiveness. R.G. was supported by research contract (IF/00564/2012) from the Portuguese Foundation for Science and Technology (FCT). Tis work was partially supported by the project PTDC/BIA-EVF/2460/2014 (FCT).Peer Reviewe

Feline leukemia virus outbreak in the critically endangered Iberian lynx ( Lynx pardinus ): high-throughput sequencing of envelope variable region A and experimental transmission

The Iberian lynx is the most endangered felid species. During winter/spring 2006/7, a feline leukemia virus (FeLV) outbreak of unexpected virulence killed about 2/3 of the infected Iberian lynxes. All FeLV-positive animals were co-infected with feline hemoplasmas. To further characterize the Iberian lynx FeLV strain and evaluate its potential virulence, the FeLV envelope gene variable region A (VRA) mutant spectrum was analyzed using the Roche 454 sequencing technology, and an in vivo transmission study of lynx blood to specified-pathogen-free cats was performed. VRA mutations indicated weak apolipoprotein B mRNA editing enzyme and catalytic polypeptide-like cytidine deaminase (APOBEC) restriction of FeLV replication, and variants characteristic of aggressive FeLV strains, such as FeLV-C or FeLV-A/61C, were not detected. Cats exposed to FeLV/Candidatus Mycoplasma haemominutum-positive lynx blood did not show a particularly severe outcome of infection. The results underscore the special susceptibility of Iberian lynxes to infectious disease

X-ray Flares of EV Lac: Statistics, Spectra, Diagnostics

We study the spectral and temporal behavior of X-ray flares from the active M-dwarf EV Lac in 200 ks of exposure with the Chandra/HETGS. We derive flare parameters by fitting an empirical function which characterizes the amplitude, shape, and scale. The flares range from very short (<1 ks) to long (10 ks) duration events with a range of shapes and amplitudes for all durations. We extract spectra for composite flares to study their mean evolution and to compare flares of different lengths. Evolution of spectral features in the density-temperature plane shows probable sustained heating. The short flares are significantly hotter than the longer flares. We determined an upper limit to the Fe K fluorescent flux, the best fit value being close to what is expected for compact loops.Comment: 9 pages; 9 figures; latex/emulateapj style; Submitted to The Astrophysical Journa

Limited evidence on the effectiveness of interventions to reduce livestock predation by large carnivores

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