scholarly journals Consequences of shortened hunting seasons by the Birds Directive on late winter teal Anas crecca abundance in France

2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
Matthieu Guillemain ◽  
David Vallecillo ◽  
Emilienne Grzegorczyk ◽  
Jean-Baptiste Mouronval ◽  
Michel Gauthier-Clerc ◽  
...  
Author(s):  
Вагид Шарапудинович Пашаев ◽  
Анатолий Мурашевич Биттиров ◽  
Црай Бесланович Кагермазов

В статье приведены сведения о видовом составе эндопаразитофауны у семи видов птиц отряда Пластинчатоклювые (Anseriformes) в регионе Северного Кавказа. У видов Anser anser L., Anser erythropus, Anas platyrhynehos L., Anas strepera L., Anas crecca L., Tadorna tadorna L., Mergus merganser L. определено 13 видов рода эймерия, 116 видов био- и геогельминтов, в том числе: Trematoda — 87 видов, Cestoda — 14 видов, Nematoda — 10 видов, Acantocephala — 5 видов с тенденцией формирования в организме птиц простых и сложных многокомпонентных паразитокомплексов. Исследования проводили в 2006 – 2014 гг. на базах ФГУ «Эльбрусский национальный парк», ФГУ «Кабардино-Балкарский государственный высокогорный заповедник», в 12 охотничьих хозяйствах и участках Кабардино-Балкарской Республики и Республики Дагестан на диких и синантропных птицах разного возраста. Паразитологическим исследованиям подвергнуты семь видов диких птиц отряда Пластинчатоклювые (всего 660 особей): серый гусь Anser anser L. — 110 особей, малый белолобый гусь Anser erythropus — 95 особей, обыкновенная кряква Anas platyrhynehos L. — 216 особей, серая утка Anas strepera L. — 100 особей, чирок-свистунок Anas crecca L. — 45 особей, пеганка Tadorna tadorna L. — 76 особей, большой крохаль Mergus merganser L. — 18 особей. Для изучения видовой структуры эндопаразитов применяли методы полного и неполного гельминтологического вскрытия. Использованы статистические методы дисперсионного анализа; вычисления выполнены с помощью программы Statistica 6.0.


1990 ◽  
Vol 82 (2) ◽  
pp. 255-261 ◽  
Author(s):  
M. E. Zarnstorff ◽  
D. S. Chamblee ◽  
J. P. Mueller ◽  
W. V. Campbell
Keyword(s):  

2021 ◽  
Author(s):  
Hyung-Ju Park ◽  
Kwang-Yul Kim

AbstractEffect of global warming on the sub-seasonal variability of the Northern Hemispheric winter (NDJFM) Pacific storm-track (PST) activity has been investigated. Previous studies showed that the winter-averaged PST has shifted northward and intensified, which was explained in terms of energy exchange with the mean field. Effect of global warming exhibits spatio-temporal heterogeneity with predominance over the Arctic region and in the winter season. Therefore, seasonal averaging may hide important features on sub-seasonal scales. In this study, distinct sub-seasonal response in storm track activities to winter Northern Hemispheric warming is analyzed applying cyclostationary empirical orthogonal function analysis to ERA5 data. The key findings are as follows. Change in the PST is not uniform throughout the winter; the PST shifts northward in early winter (NDJ) and intensifies in late winter (FM). In early winter, the combined effect of weakened baroclinic process to the south of the climatological PST and weakened barotropic damping to the north is responsible for the northward shift. In late winter, both processes contribute to the amplification of the PST. Further, change in baroclinic energy conversion is quantitatively dominated by eddy heat flux, whereas axial tilting of eddies is primarily responsible for change in barotropic energy conversion. A close relationship between anomalous eddy heat flux and anomalous boundary heating, which is largely determined by surface turbulent heat flux, is also demonstrated.


2014 ◽  
Vol 128 (3) ◽  
pp. 272 ◽  
Author(s):  
Gilbert Proulx

Late-winter habitat use by the Fisher, Pekania pennanti (Erxleben, 1777) in northwestern Saskatchewan was assessed in February 2009, 2011, and 2012. A total of 78 Fisher tracks were recorded over 60 300 m of snowshoe surveys. Fisher tracks were significantly less frequent than expected in Tamarack (Larix laricina [Du Roi] K. Koch) stands with > 40% crown closure and mainly 0–10 m trees (P < 0.05) and in open areas. Fishers used other habitat types equal to availability, including muskeg and coniferous, mixed, and deciduous forest stands. Maintaining mosaics of forest stands of different seral stages interspersed with muskeg would meet the late-winter habitat needs of Fishers in the Boreal Plains Ecozone of northwestern Saskatchewan.


Radiocarbon ◽  
2020 ◽  
pp. 1-6
Author(s):  
J H Park ◽  
J Southon ◽  
JW Seo ◽  
P P Creasman ◽  
W Hong ◽  
...  

ABSTRACT The AD 775 peak in Δ14C (henceforth, M12) was first measured by Miyake et al. and has since been confirmed globally. Here we present earlywood and latewood Δ14C values from tree rings of pinyon pine (Pinus edulis) from Mummy Cave, Canyon de Chelly National Monument, Chinle, Arizona, USA, for the period AD 770–780. These data reconfirm the timing of M12 and show a small rise in Δ14C in AD 774 latewood. Allowing for the delay in lateral transfer of radiocarbon produced at high latitude, this suggests that 14C peak production occurred in late winter or spring of AD 774. Additionally, Δ14C decreased slightly in the earlywood of AD 775 and increased in the latewood of AD 775 to a higher level than that observed in AD 774.


Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 174
Author(s):  
Günther Heinemann ◽  
Sascha Willmes ◽  
Lukas Schefczyk ◽  
Alexander Makshtas ◽  
Vasilii Kustov ◽  
...  

The parameterization of ocean/sea-ice/atmosphere interaction processes is a challenge for regional climate models (RCMs) of the Arctic, particularly for wintertime conditions, when small fractions of thin ice or open water cause strong modifications of the boundary layer. Thus, the treatment of sea ice and sub-grid flux parameterizations in RCMs is of crucial importance. However, verification data sets over sea ice for wintertime conditions are rare. In the present paper, data of the ship-based experiment Transarktika 2019 during the end of the Arctic winter for thick one-year ice conditions are presented. The data are used for the verification of the regional climate model COSMO-CLM (CCLM). In addition, Moderate Resolution Imaging Spectroradiometer (MODIS) data are used for the comparison of ice surface temperature (IST) simulations of the CCLM sea ice model. CCLM is used in a forecast mode (nested in ERA5) for the Norwegian and Barents Seas with 5 km resolution and is run with different configurations of the sea ice model and sub-grid flux parameterizations. The use of a new set of parameterizations yields improved results for the comparisons with in-situ data. Comparisons with MODIS IST allow for a verification over large areas and show also a good performance of CCLM. The comparison with twice-daily radiosonde ascents during Transarktika 2019, hourly microwave water vapor measurements of first 5 km in the atmosphere and hourly temperature profiler data show a very good representation of the temperature, humidity and wind structure of the whole troposphere for CCLM.


2006 ◽  
Vol 63 (1) ◽  
pp. 151-160 ◽  
Author(s):  
Stelios Katsanevakis ◽  
George Verriopoulos

Abstract The population density of Octopus vulgaris was measured by visual census with scuba diving in coastal areas in Greece (eastern Mediterranean). A time-variant, stage-classified, matrix population model was developed to interpret the seasonal variation of octopus stage densities and to estimate several life cycle parameters. An annual and a semi-annual periodic cycle were found in the stage densities. A main peak of benthic settlement was observed during summer and a secondary, irregular one during late autumn. Two spawning peaks were estimated, a main one during late winter–spring and a secondary one during late summer–early autumn. More than 50% of the just-settled individuals will eventually die after 3 months. Mortality rate declines, as individuals grow larger, reaches a minimum approximately 6 months after settlement, and then grows again probably because of terminal spawning. The life expectancy of recently settled individuals (<50 g) during their summer peak is approximately 5 months. The lifespan of the common octopus is estimated to be between 12 and 15 months. The octopuses' mean specific growth rates (±s.d.) in their natural environment were 1.61 ± 0.30 d−1 for 50–200 g individuals and 1.19 ± 0.31 d−1 for 200–500 g individuals.


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