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1.
Rev. biol. trop ; 72(1): e55265, ene.-dic. 2024. tab, graf
Artículo en Inglés | SaludCR, LILACS | ID: biblio-1559322

RESUMEN

Abstract Introduction: The Wood Thrush is a migratory bird that has experienced dramatic declines in its populations in recent decades. This species overwinters in forest fragments with intermediate levels of habitat modification in Central America. However, more studies detailing the use of remnant forests through time are needed to elucidate the threats this species faces in the wintering grounds. Objective: To understand the effects of environmental and forest structure variables on the occupancy of Wood Thrush in Northern Costa Rica. Methods: The study area was the Área de Conservación Guanacaste (ACG), located in Northern Costa Rica, in December 2016, and during the 2018-2019 migration season. We estimated Wood Thrush occupancy and detection probability in four locations of ACG (dry forest, cloud forest, and two locations in the wet forest) using single-season occupancy models. We also estimated Wood Thrush occupancy and probability of persistence in different months in three vegetation types (open area, secondary forest, and old-growth forest) in the wet forest of ACG using a multi-season occupancy model approach. Results: Wood Thrush occupancy was best described by precipitation in the four locations of the ACG; the probability of occupancy increased with precipitation. The average occupancy of Wood Thrushes varied with vegetation type: open area with shrubs and forest edge (0.69 ± 0.09), secondary forest (0.46 ± 0.1), and old-growth forest (0.61 ± 0.1). Wood Thrush probability of persistence responded partially to changes in precipitation, with an unexpected increase in persistence when the rainfall continued decreasing in the season. Conclusion: Wood Thrush occupancy was best predicted by changes in precipitation considering a larger spatial scale. Its probability of persistence partially varied with precipitation. An increase in persistence closer to Spring migration might be explained by the start of the breeding season of resident birds, potentially reducing territorial conflicts and conserving energy before migration. The long-term protection of wet forests in Northern Costa Rica is of paramount importance for the conservation of Wood Thrushes in their wintering grounds.


Resumen Introducción: El Zorzal del Bosque es un ave migratoria que ha experimentado caídas dramáticas en sus poblaciones en las últimas décadas. Esta especie pasa el invierno en fragmentos de bosque con niveles intermedios de modificación de hábitat en Centroamérica. Sin embargo, se necesitan más estudios que detallen el uso de los bosques remanentes a lo largo del tiempo para dilucidar las amenazas que enfrenta esta especie en las zonas de invernada. Objetivo: Comprender los efectos de variables ambientales y de estructura del bosque en la ocurrencia del Zorzal del Bosque en el Norte de Costa Rica. Métodos: El área de estudio fue el Área de Conservación Guanacaste (ACG), ubicada en el Norte de Costa Rica, en diciembre de 2016, y en la temporada migratoria 2018-2019. Estimamos la ocurrencia y la probabilidad de detección del Zorzal del Bosque en cuatro ubicaciones de ACG (bosque seco, bosque nuboso y dos ubicaciones en el bosque húmedo) utilizando modelos de ocurrencia de una sola temporada. También estimamos la ocurrencia del Zorzal del Bosque y la probabilidad de persistencia en diferentes meses en tres tipos de vegetación (área abierta, bosque secundario y bosque primario) en el bosque húmedo de ACG utilizando un enfoque de modelo de ocurrencia multi-estacional. Resultados: La ocurrencia del Zorzal del Bosque estuvo mejor descrita por la precipitación en las cuatro localidades del ACG; la probabilidad de ocurrencia aumentó con las precipitaciones. La ocurrencia media de zorzales varió con el tipo de vegetación: área abierta con arbustos y borde de bosque (0.69 ± 0.09), bosque secundario (0.46 ± 0.1) y bosque primario (0.61 ± 0.1). La probabilidad de persistencia del zorzal respondió parcialmente a cambios en la precipitación, con un aumento inesperado en la persistencia cuando las precipitaciones continuaron disminuyendo en la temporada. Conclusión: La ocurrecia del Zorzal del Bosque varió con la precipitación considerando una escala espacial mayor. Su probabilidad de persistencia varió parcialmente con la precipitación. Un aumento en la persistencia más cerca de la migración de primavera podría explicarse por el inicio de la temporada de reproducción de las aves residentes, lo que podría reducir los conflictos territoriales y conservar energía antes de la migración. La protección a largo plazo de los bosques húmedos en el norte de Costa Rica es de suma importancia para la conservación de los Zorzales del Bosque en sus zonas de invernada.


Asunto(s)
Animales , Migración Animal , Passeriformes , Estaciones del Año , Costa Rica
2.
J Environ Manage ; 370: 122360, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39243644

RESUMEN

The availability of high-quality food resources is a critical determinant of wildlife fitness. Over the past two decades, phenological mismatch - the temporal misalignment between animals' peak nutrient demand and optimal resource availability - has emerged as a significant conservation challenge. This issue is particularly worrisome for migratory birds, which must accumulate energy reserves to meet the elevated metabolic demands of migration between breeding and wintering grounds. In Poyang Lake, a crucial wintering ground along the East Asian-Australasian flyway, increasing asynchrony between vegetation growth and the migration of herbivorous waterbirds significantly impedes conservation efforts and presents a major management challenge for this Ramsar wetland. This study evaluates the efficacy of mowing, a grassland management measure, in regulating plant growth processes and restoring food resources for geese. In-situ mowing experiments were conducted with varying timings in Carex wet meadows, the primary foraging habitats of geese. Optimal mowing times were identified, and the maximum goose carrying capacity was assessed by comparing Carex growth and nutritional dynamics with goose dietary requirements. The results reveal that mowing effectively slows down the aging process of Carex, and protein content is identified as a critical limiting factor for geese foraging. Different mowing timings extend the suitable foraging period by 11-25 days. Estimates suggest varying carrying capacities with different mowing timings, supporting goose populations ranging from 133 to 2,046 in Changhuchi Lake during wintering. The optimal mowing window is early October, avoiding dates before late September and after late November. Moreover, multiple-stage mowing is recommended to accommodate different wintering stages. The study highlights mowing as a potential habitat restoration approach for goose conservation, effectively mitigating the challenges imposed by phenological mismatch directly and indirectly caused by anthropogenic activities.

3.
Curr Zool ; 70(4): 505-512, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39176067

RESUMEN

Migratory connectivity describes the linkage between breeding and nonbreeding sites, having major ecological implications in birds: 1 season influence the success of an individual or a population in the following season. Most studies on migratory connectivity have used large-scale approaches, often considering regional populations, but fine-scale studies are also necessary to understand colony connectivity. The lesser kestrel Falco naumanni, an insectivorous migratory raptor which form colonies during the breeding period, was considered to have strong connectivity based on regional populations. However, no small-scale studies on migratory connectivity have been conducted. Therefore, we GPS (Global Positioning System)-tracked 40 adult lesser kestrels from 15 different Spanish breeding colonies, estimating the overlap index between home ranges and the distance between their centroids. It was found that lesser kestrels from the same breeding colony placed their nonbreeding areas at 347 ± 281 km (mean ± standard deviation) away from each other (range = 23-990), and their home ranges overlapped by 38.4 ± 23.6%. No differences between intra-colony and inter-colony metrics were found, which suggests that lesser kestrels from the same breeding cluster do not overwinter together, but they spread out and mixed independently of the colony belonging throughout the nonbreeding range of the species. Ultimately, this study highlights the importance of performing connectivity studies using fine-scale approaches.

4.
Environ Res ; 261: 119641, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39053757

RESUMEN

Mercury (Hg), especially methylmercury (MeHg), is a pervasive contaminant that poses significant risks to birds occupying high trophic levels. However, we have little knowledge about the mercury exposure and its risks for birds in Poyang Lake basin, China. Therefore, during 2020-2021, we investigated MeHg concentrations in breast feathers of wintering migratory birds (n = 430 from 43 species belonging to 9 orders) in Poyang Lake Nanji Wetland and Jiangxi Nanfengmian National Nature Reserve, China. MeHg concentrations in breast feathers varied greatly by species, foraging guilds and taxonomic orders, among which the highest concentration was detected in great egret (8849 ± 5975 ng g-1 dw). Comparing with studies worldwide, high MeHg concentrations in feathers of Ardeidae from Pelecaniformes were found in this area. Moreover, herons migrating between northern and southern China had lower MeHg concentration than residents in southern China related to habitat Hg. Considering the applicability and sensitivity of the equations for the transformation of MeHg concentrations in feathers to blood-equivalent total Hg (THg) values, method CJ that the equation based on songbirds was used for the transformation of the songbirds and the equation based on seabirds for the others performed better than other three for risk assessment of bird Hg in this study. 23.1% of birds from Poyang Lake were at risk of Hg exposure based on the method CJ. Carnivorous birds from Pelecaniformes had the highest risk levels, with 37.2% categorized as no risk (≤200 ng g-1 ww), 48.9% as low risk (200-1000 ng g-1 ww), 11.1% as moderate risk (1000-3000 ng g-1 ww), 1.1% as high risk (3000-4000 ng g-1 ww), and 1.7% as severe risk (>4000 ng g-1 ww). These risks suggest long-term monitoring and further advanced studies about freshwater waterbirds Hg exposure is necessary.


Asunto(s)
Migración Animal , Aves , Monitoreo del Ambiente , Plumas , Lagos , Compuestos de Metilmercurio , Animales , Compuestos de Metilmercurio/análisis , China , Lagos/química , Plumas/química , Contaminantes Químicos del Agua/análisis , Estaciones del Año , Exposición a Riesgos Ambientales/análisis , Medición de Riesgo
5.
Sci Rep ; 14(1): 17527, 2024 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080395

RESUMEN

The equilibrium theorem provided a fundamental framework for understanding species' distributions and movement in fragmented ecosystems. Wetland-dependent avian species are model organisms to test insular predictions within protected area networks because their mobility allows surveillance of isolated patches without landscape barriers. We hypothesized size and isolation would influence functional connectivity of sanctuaries by GPS-marked wintering mallards (Anas platyrhynchos) within a mesocosm protected sanctuary area network. We evaluated functional connectivity and sanctuary use, measured by movements between sanctuaries, using a multistate modeling framework. Proximity drove connectivity, underscoring that patch isolation-not size-influenced connectivity, even for an avian species with no ascertainable landscape resistance or barriers. We also found that sanctuary use increased overwintering survival by reducing harvest mortality. Our test of equilibrium theory predictions demonstrated that isolation of protected sanctuary areas supersedes their size in determining functional connectivity for mallards and access to these areas may have direct fitness consequences. Our findings could refine land acquisition, restoration, and management practices with equal or greater emphasis on adjacency in protected area network design, especially for wetland-dependent migratory gamebirds.


Asunto(s)
Migración Animal , Conservación de los Recursos Naturales , Patos , Ecosistema , Estaciones del Año , Humedales , Animales , Patos/fisiología , Conservación de los Recursos Naturales/métodos , Migración Animal/fisiología , Anseriformes/fisiología
6.
BMC Microbiol ; 24(1): 232, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38951807

RESUMEN

BACKGROUND: Migratory birds exhibit heterogeneity in foraging strategies during wintering to cope with environmental and migratory pressures, and gut bacteria respond to changes in host diet. However, less is known about the dynamics of diet and gut fungi during the wintering period in black-necked cranes (Grus nigricollis). RESULTS: In this work, we performed amplicon sequencing of the trnL-P6 loop and ITS1 regions to characterize the dietary composition and gut fungal composition of black-necked cranes during wintering. Results indicated that during the wintering period, the plant-based diet of black-necked cranes mainly consisted of families Poaceae, Solanaceae, and Polygonaceae. Among them, the abundance of Solanaceae, Polygonaceae, Fabaceae, and Caryophyllaceae was significantly higher in the late wintering period, which also led to a more even consumption of various food types by black-necked cranes during this period. The diversity of gut fungal communities and the abundance of core fungi were more conserved during the wintering period, primarily dominated by Ascomycota and Basidiomycota. LEfSe analysis (P < 0.05, LDA > 2) found that Pyxidiophora, Pseudopeziza, Sporormiella, Geotrichum, and Papiliotrema were significantly enriched in early winter, Ramularia and Dendryphion were significantly enriched in mid-winter, Barnettozyma was significantly abundant in late winter, and Pleuroascus was significantly abundant in late winter. Finally, mantel test revealed a significant correlation between winter diet and gut fungal. CONCLUSIONS: This study revealed the dynamic changes in the food composition and gut fungal community of black-necked cranes during wintering in Dashanbao. In the late wintering period, their response to environmental and migratory pressures was to broaden their diet, increase the intake of non-preferred foods, and promote a more balanced consumption ratio of various foods. Balanced food composition played an important role in stabilizing the structure of the gut fungal community. While gut fungal effectively enhanced the host's food utilization rate, they may also faced potential risks of introducing pathogenic fungi. Additionally, we recongnized the limitations of fecal testing in studying the composition of animal gut fungal, as it cannot effectively distinguished between fungal taxa from food or soil inadvertently ingested and intestines. Future research on functions such as cultivation and metagenomics may further elucidate the role of fungi in the gut ecosystem.


Asunto(s)
Aves , Dieta , Hongos , Microbioma Gastrointestinal , Estaciones del Año , Animales , Hongos/clasificación , Hongos/genética , Hongos/aislamiento & purificación , Aves/microbiología , Tracto Gastrointestinal/microbiología , ADN de Hongos/genética , Filogenia
7.
Microorganisms ; 12(6)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38930537

RESUMEN

Against a backdrop of declining bee colony health, this study aims to gain a better understanding of the impact of an antimicrobial (Fumidil B®, Can-Vet Animal Health Supplies Ltd., Guelph, ON, Canada) and a probiotic (Bactocell®, Lallemand Inc., Montreal, QC, Canada) on bees' microbiota and the health of their colonies after wintering. Therefore, colonies were orally exposed to these products and their combination before wintering in an environmental room. The results show that the probiotic significantly improved the strength of the colonies in spring by increasing the total number of bees and the number of capped brood cells. This improvement translated into a more resilient structure of the gut microbiota, highlighted by a more connected network of interactions between bacteria. Contrastingly, the antimicrobial treatment led to a breakdown in this network and a significant increase in negative interactions, both being hallmarks of microbiota dysbiosis. Although this treatment did not translate into a measurable colony strength reduction, it may impact the health of individual bees. The combination of these products restored the microbiota close to control, but with mixed results for colony performance. More tests will be needed to validate these results, but the probiotic Bactocell® could be administrated as a food supplement before wintering to improve colony recovery in spring.

8.
Sci Rep ; 14(1): 14204, 2024 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902276

RESUMEN

The reaction of birds to the nest parasite, the European cuckoo Cuculus canorus, has been the subject of extensive testing in various aspects. However, while the cuckoo is a long-distance migrant, some of its hosts are sedentary species. In this study, we aimed to investigate whether species, primarily hosts, react to the presence of the cuckoo also in the winter season. This behaviour may involve an attempt to drive the parasite away from locations that will subsequently become their breeding sites. During playback experiments conducted in the winter of 2021/2022 in Poland, we demonstrated that numerous bird species react to the male cuckoo calls in winter. These calls may be perceived as a source of danger, particularly by cuckoo hosts, who responded to this call more frequently than non-hosts and the control species (pigeon). Nonetheless, the birds' reactions were not strong, as they did not approach the source of the call. However, our results are constrained by the limited number of cuckoo host species wintering in Poland. To better evaluate the intensity of bird responses to the male cuckoo's call during the non-breeding season, further studies should be conducted in regions where a greater variety of species, especially those most susceptible to parasitism, overwinter.


Asunto(s)
Passeriformes , Estaciones del Año , Animales , Masculino , Passeriformes/fisiología , Passeriformes/parasitología , Polonia , Vocalización Animal/fisiología , Comportamiento de Nidificación/fisiología , Migración Animal/fisiología
9.
Ecol Lett ; 27(5): e14430, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38714364

RESUMEN

Wintering birds serve as vital climate sentinels, yet they are often overlooked in studies of avian diversity change. Here, we provide a continental-scale characterization of change in multifaceted wintering avifauna and examine the effects of climate change on these dynamics. We reveal a strong functional reorganization of wintering bird communities marked by a north-south gradient in functional diversity change, along with a superimposed mild east-west gradient in trait composition change. Assemblages in the northern United States saw contractions of the functional space and increases in functional evenness and originality, while the southern United States saw smaller contractions of the functional space and stasis in evenness and originality. Shifts in functional diversity were underlined by significant reshuffling in trait composition, particularly pronounced in the western and northern United States. Finally, we find strong contributions of climate change to this functional reorganization, underscoring the importance of wintering birds in tracking climate change impacts on biodiversity.


Asunto(s)
Biodiversidad , Aves , Cambio Climático , Estaciones del Año , Animales , Aves/fisiología , Estados Unidos
10.
Animals (Basel) ; 14(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38731356

RESUMEN

Moroccan wetlands host up to half a million wintering birds and provide a stopover for tens of thousands of migrants, while they are inhabited by few nesting species. Most of this avifauna prefers to use the large coastal wetlands or reservoirs, while many species are dispersed across hundreds of small inland wetlands of various types. In this study, we monitored the wintering avifauna of 11 wetlands of the Saïss plain and its adjacent Atlas Mountains (north-center of Morocco), during six wintering seasons (2017-2018 to 2022-2023), with the objective of assessing the importance of this region as a waterbird wintering area. Using the richness of the species, we determine the bird population changes during this pentad and between the different types of wetlands (natural, human-made, and natural wetlands). During this study, we recorded 51 species, belonging to 17 families, among which exist four remarkable birds: the endangered Oxyura leucocephala, the vulnerable Aythya ferina and the near-threatened Aythya nyroca and Limosa limosa. Bird diversity is higher in human-made ecosystems than in peri-urban and natural ecosystems, while the populations' size is similar in urban and non-urban wetlands. With regard to bird conservation, these inland wetlands, mainly the small ones, are threatened by recurrent droughts and various anthropic stressors, which we describe using our observations of the two last decades (2003-2023). The loss of habitat is significant, reaching 348.5 hectares, while the impacts of reduced precipitation and temperature increase are particularly evident in the mountainous natural lakes.

11.
Molecules ; 29(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38731424

RESUMEN

Climate change, which causes periods with relatively high temperatures in winter in Poland, can lead to a shortening or interruption of the cold hardening of crops. Previous research indicates that cold acclimation is of key importance in the process of acquiring cereal tolerance to stress factors. The objective of this work was to verify the hypothesis that both natural temperature fluctuations and the plant genotype influence the content of metabolites as well as proteins, including antioxidant enzymes and photosystem proteins. The research material involved four winter triticale genotypes, differing in their tolerance to stress under controlled conditions. The values of chlorophyll a fluorescence parameters and antioxidant activity were measured in their seedlings. Subsequently, the contribution of selected proteins was verified using specific antibodies. In parallel, the profiling of the contents of chlorophylls, carotenoids, phenolic compounds, and proteins was carried out by Raman spectroscopy. The obtained results indicate that a better PSII performance along with a higher photosystem II proteins content and thioredoxin reductase abundance were accompanied by a higher antioxidant activity in the field-grown triticale seedlings. The Raman studies showed that the cold hardening led to a variation in photosynthetic dyes and an increase in the phenolic to carotenoids ratio in all DH lines.


Asunto(s)
Proteínas de Plantas , Plantones , Espectrometría Raman , Triticale , Plantones/metabolismo , Plantones/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Triticale/genética , Triticale/metabolismo , Espectrometría Raman/métodos , Clorofila/metabolismo , Temperatura , Carotenoides/metabolismo , Antioxidantes/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Complejo de Proteína del Fotosistema II/genética , Estaciones del Año , Clorofila A/metabolismo
12.
Pathogens ; 13(5)2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38787232

RESUMEN

Surveillance of avian influenza virus (AIV) was conducted in the 2021-2022 winter season at a wintering site of migratory Anatidae in Japan. An H5N8 subtype high pathogenicity AIV (HPAIV) with a unique gene constellation and four low pathogenicity AIVs (LPAIVs) were isolated from environmental samples. The genetic origin of the HPAIV (NK1201) was determined with whole-genome sequencing and phylogenetic analyses. Six of NK1201's eight genes were closely related to HA clade 2.3.4.4b H5N8 subtype HPAIVs, belonging to the G2a group, which was responsible for outbreaks in poultry farms in November 2021 in Japan. However, the remaining two genes, PB1 and NP, most closely matched those of the LPAIVs H7N7 and H1N8, which were isolated at the same place in the same 2021-2022 winter. No virus of the NK1201 genotype had been detected prior to the 2021-2022 winter, indicating that it emerged via genetic reassortment among HPAIV and LPAIVs, which were prevalent at the same wintering site. In addition, experimental infection in chickens indicated that NK1201 had slightly different infectivity compared to the reported infectivity of the representative G2a group H5N8 HPAIV, suggesting that the PB1 and NP genes derived from LPAIVs might have affected the pathogenicity of the virus in chickens. Our results directly demonstrate the emergence of a novel genotype of H5N8 HPAIV through gene reassortment at a wintering site. Analyses of AIVs at wintering sites can help to identify the emergence of novel HPAIVs, which pose risks to poultry, livestock, and humans.

13.
J Dairy Sci ; 107(9): 7079-7091, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38642653

RESUMEN

In countries with pasture-based dairy systems and relatively cold winters, such as New Zealand, it is common to manage pregnant, nonlactating cows on forage crop paddocks rather than pasture, due to slow pasture growth rates. Wintering dairy cattle on grazed crops can compromise welfare if wet and muddy underfoot conditions occur, which can reduce lying. This study investigated behavioral and physiological indicators of welfare of cows under 2 wintering practices: cows managed on and grazed kale crop (Brassica oleracea), and cows managed on pasture with baled hay. Following dry-off (d 0), 80 cows were randomly assigned to 1 of the 2 wintering practices (40 cows/practice) and monitored between d 4 and 32 (phase 1). During this period, lying and stepping behavior was continuously recorded using leg-based accelerometers. Blood samples were obtained at d 0 and 32 for measurements of thyroxine (T4), nonesterified fatty acids (NEFA), white blood cells (WBC), and red blood cells. All data for phase 1 were presented descriptively due to the lack of treatment replication. Daily mean air temperature during this period was 5.2°C (range: 0.0-10.7°C), and rainfall was 1.1 mm/d (range: 0-5.6mm/d). Between d 4 and 32, cows in both groups spent similar amounts of time lying (pasture with hay cows: 8.9 h/24 h ± 2.57, kale crop cows: 8.7 h/24 h ± 3.06, mean ± SEM). Both groups reduced their lying on wet and cold days, and there was evidence of rebound lying once unfavorable weather conditions stopped. Cows on kale crop had numerically higher NEFA and lower WBC compared with cows managed on pasture, although most physiological values were within normal ranges. In a second phase of the study (d 34 and 35), cows were managed under controlled, replicated conditions in the 2 wintering practices using typical on-farm stocking rates (2 or 4 cows per group in the pasture with hay and kale crop treatments, respectively; n = 10 groups/treatment). During this period, cow behavior, skin and surface temperatures, hygiene scores, feed intakes, and ground conditions were measured. Weather conditions during the 48-h exposure were mostly cold and dry (mean air temperature: 7.8°C, range: -2.2 to 20.5°C). Cows managed on pasture with hay spent more time lying down on the first day of exposure; however, this was likely due to less space being available to kale cows on this day. Cows managed on pasture with hay ruminated more than cows on kale crop on both days of observations (d 1: 37.9% vs. 30.9% of observations, d 2: 36.8% vs. 28.7% of observations for pasture with hay and kale crop groups, respectively) and were lying more often in postures indicative of greater thermal comfort. Cows managed on pasture with hay had higher skin and surface temperatures compared with cows on kale crop, whereas cows on kale crop had dirtier coats. Results suggest that opportunities for thermal comfort were greater for cows managed on pasture with hay bales, which may be due to increased rumination activities and more insulated lying areas.


Asunto(s)
Industria Lechera , Animales , Bovinos/fisiología , Femenino , Embarazo , Industria Lechera/métodos , Estaciones del Año , Lactancia , Bienestar del Animal , Nueva Zelanda , Conducta Animal
14.
Ecol Evol ; 14(4): e11252, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38601856

RESUMEN

The "pace-of-life" syndrome (POLS) framework can encompass multiple personality axes that drive important functional behaviors (e.g., foraging behavior) and that co-vary with multiple life history traits. Food hoarding is an adaptive behavior important for an animal's ability to adapt to seasonal fluctuations in food availability. However, the empirical evidence for the relationships between animal personality and hoarding behavior remains unclear, including its fitness consequences in the POLS framework. In this study, the Mongolian gerbil (Meriones unguiculatus), a social rodent, was used as a model system to investigate how boldness or shyness is associated with food hoarding strategies during the food hoarding season and their impact on over-winter survival and reproduction at both individual and group levels. The results of this study showed that, compared with shy gerbils, bold gerbils had a lower effort foraging strategy during the food hoarding season and exhibited lower over-winter survival rates. However, bold-shy personality differences had no effect on over-winter reproduction. These findings suggest that the personality is a crucial factor influencing the foraging strategy during the food hoarding season in Mongolian gerbils. Personality may be related to energy states or the reaction to environmental changes (e.g., predation risk and food availability) in bold or shy social animals. These results reflect animal life history trade-offs between current versus future reproduction and reproduction versus self-maintenance, thereby helping Mongolian gerbils in adapting to seasonal fluctuations in their habitat.

15.
Oecologia ; 204(3): 613-624, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38400948

RESUMEN

When wintering at different sites, individuals from the same breeding population can experience different conditions, with costs and benefits that may have implications throughout their lifetime. Using a dataset from a longitudinal study on Eurasian Spoonbills from southern France, we explored whether survival rate varied among individuals using different wintering sites. In the last 13 years, more than 3000 spoonbills have been ringed as chicks in Camargue. These birds winter in five main regions that vary in both migratory flyway (East Atlantic vs. Central European) and migration distance (long-distance vs. short-distance vs. resident). We applied Cormack-Jolly-Seber models and found evidence for apparent survival to correlate with migration distance, but not with flyway. During the interval between the first winter sighting and the next breeding period, long-distance migrants had the lowest survival, independently of the flyway taken. Additionally, as they age, spoonbills seem to better cope with migratory challenges and wintering conditions as no differences in apparent survival among wintering strategies were detected during subsequent years. As dispersal to other breeding colonies was rarely observed, the lower apparent survival during this period is likely to be partly driven by lower true survival. This supports the potential role of crossing of natural barriers and degradation of wintering sites in causing higher mortality rates as recorded for a variety of long-distance migrants. Our work confirms variation in demographic parameters across winter distribution ranges and reinforces the importance of longitudinal studies to better understand the complex demographics of migratory species.


Asunto(s)
Migración Animal , Aves , Humanos , Animales , Estudios Longitudinales , Francia , Estaciones del Año
16.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469385

RESUMEN

Abstract Variety assortment enhancement is a normal task that involves enhancing the assortment's quality and upgrading varieties. The findings of a research of imported grape varieties in the southeast of Kazakhstan, namely in the Almaty region's bottom-mountain zone, are presented in this article. The onset and conclusion of the main phenological phases of a grape plant throughout the vegetative period were directly influenced by the climatic and meteorological conditions of this district. In comparison to the recognized variety Almaty early-maturing, it has been proven that types Priusadebny, Iyulsky, and Kuibyshevsk early-maturing have a high degree of eyes wintering buds and may provide a high-quality crop in this location.


Resumo O aprimoramento da variedade é uma tarefa normal que envolve o aprimoramento da qualidade da variedade e o aprimoramento das variedades. As descobertas de uma pesquisa de variedades de uvas importadas no sudeste do Cazaquistão, ou seja, na zona de base da montanha da região de Almaty, são apresentadas neste artigo. O início e a conclusão das principais fases fenológicas de uma videira ao longo do período vegetativo foram diretamente influenciados pelas condições climáticas e meteorológicas deste distrito. Em comparação com a variedade reconhecida Almaty de maturação precoce, foi comprovado que os tipos Priusadebny, Iyulsky e Kuibyshevsk de maturação precoce têm um alto grau de gomos de inverno de olhos e podem fornecer uma safra de alta qualidade neste local.

17.
Braz. j. biol ; 84: e258275, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1364498

RESUMEN

Variety assortment enhancement is a normal task that involves enhancing the assortment's quality and upgrading varieties. The findings of a research of imported grape varieties in the southeast of Kazakhstan, namely in the Almaty region's bottom-mountain zone, are presented in this article. The onset and conclusion of the main phenological phases of a grape plant throughout the vegetative period were directly influenced by the climatic and meteorological conditions of this district. In comparison to the recognized variety Almaty early-maturing, it has been proven that types Priusadebny, Iyulsky, and Kuibyshevsk early-maturing have a high degree of eyes wintering buds and may provide a high-quality crop in this location.


O aprimoramento da variedade é uma tarefa normal que envolve o aprimoramento da qualidade da variedade e o aprimoramento das variedades. As descobertas de uma pesquisa de variedades de uvas importadas no sudeste do Cazaquistão, ou seja, na zona de base da montanha da região de Almaty, são apresentadas neste artigo. O início e a conclusão das principais fases fenológicas de uma videira ao longo do período vegetativo foram diretamente influenciados pelas condições climáticas e meteorológicas deste distrito. Em comparação com a variedade reconhecida Almaty de maturação precoce, foi comprovado que os tipos Priusadebny, Iyulsky e Kuibyshevsk de maturação precoce têm um alto grau de gomos de inverno de olhos e podem fornecer uma safra de alta qualidade neste local.


Asunto(s)
Cambio Climático , Producción de Cultivos , Vitis , Kazajstán
18.
Animals (Basel) ; 13(17)2023 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-37684990

RESUMEN

Species distribution models (SDMs) are effective tools for wildlife conservation and management, as they employ the quantification of habitat suitability and environmental niches to evaluate the patterns of species distribution. The utilization of SDMs at various scales in a hierarchical approach can provide additional and complementary information, significantly improving decision-making in local wildlife conservation initiatives. In this study, we considered the appropriate spatial scale and data resolution to execute species distribution modeling, as these factors greatly influence the modeling procedures. We developed SDMs for wintering black storks at both the regional and local scales. At the regional scale, we used climatic and climate-driven land use/land cover (LULC) variables, along with wintering occurrence points, to develop models for mainland China. At the local scale, we used local environmental variables and locally gathered wintering site data to develop models for Shaanxi province. The predictions from both the regional and local models were then combined at the provincial level by overlapping suitable areas based on climatic and local conditions. We compared and evaluated the resulting predictions using seven statistical metrics. The national models provide information on the appropriate climatic conditions for the black stork during the wintering period throughout China, while the provincial SDMs capture the important local ecological factors that influence the suitability of habitats at a finer scale. As anticipated, the national SDMs predict a larger extent of suitable areas compared to the provincial SDMs. The hierarchical prediction approach is considered trustworthy and, on average, yields better outcomes than non-hierarchical methods. Our findings indicate that human-driven LULC changes have a significant and immediate impact on the wintering habitat of the black stork. However, the effects of climate change seem to be reducing the severity of this impact. The majority of suitable wintering habitats lie outside the boundaries of protected areas, highlighting the need for future conservation and management efforts to prioritize addressing these conservation gaps and focusing on the protection of climate refuges.

19.
Ecotoxicol Environ Saf ; 264: 115431, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37666202

RESUMEN

Heavy metal contamination poses a significant environmental threat to wildlife on global scale, making accurate assessment of exposure risk crucial for conservation efforts, particularly for vulnerable species. Existing risk assessment models have been widely used, but their construction process lacks comprehensive considerations. In this study, we constructed an optimized health risk assessment model based on the well-established "Liu's model" and "ADI model", and applied the pollution allocation factor (AF) to accurately assess the risk of heavy metal exposure to wildlife. Our model was applied to assess exposure risk of heavy metal for the black-necked crane(Grus nigricollis), a flagship species in the alpine wetland ecosystem of Caohai Wetland. Soil, plant and black-necked crane fecal samples were collected from the Caohai Wetland and surrounding areas in Guizhou, China. We revealed varying degrees of As, Cd, Cr, Ni, Pb, and Zn contamination in soil and plants from different habitats, exceeding the background or plant limit values. This indicated that the black-necked crane and other waterbirds living in Caohai Wetland are suffering with the multi-elemental heavy metal contamination, especially in the gutterway and grassland. The exposure dose of As, Cd, Cr, Ni, Cu, and Zn toward black-necked cranes differed significantly in soil and plant pathways (P < 0.05). As, Cd, Cu, and Zn were mainly derived from plants consumption, while Cr and Ni originated from soil. Considering the contribution of soil and plant pathways to heavy metal exposure in black-necked cranes, the exposure doses of each elements calculated via food intake accounted for over half of the exposure calculated via feces (AF>0.5). The risk assessment model identified Cr and Pb were the highest risk elements for black-necked cranes, with exposure risk simulated through feces exceeding those through food. These findings suggested that current Liu's model may underestimate the effects of other pathways and medium. Therefore, we proposed a more comprehensive and accurate model for evaluating the exposure risk of black-necked cranes, incorporating AF to quantify the contribution of risk sources to black-necked cranes and understand their overall health risk. This model can serve as a useful tool for the conservation and habitat quality improvement of the black-necked cranes and other waterbirds.


Asunto(s)
Metales Pesados , Humedales , Animales , Animales Salvajes , Aves , Cadmio , China , Ecosistema , Plomo , Suelo
20.
Ying Yong Sheng Tai Xue Bao ; 34(6): 1639-1648, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37694427

RESUMEN

To gain a more comprehensive understanding of habitat preferences, potential wintering area distribution and drivers of population expansion of Grus leucogeranus, we selected 70 geographical distribution points and 11 environmental variables in its wintering period from 2015-2022. We modeled suitable habitat patterns for G. leucogeranus in China using MaxEnt model, and analyzed the relationship between suitable habitat distribution and environmental factors. The results showed that the dominant factors affecting the overwintering distribution of G. leucogeranus were distance to mudflats, elevation, average precipitation in February, distance to water sources, minimum temperature in December, and land use type, with a cumulative contribution rate of 94.6%. The wintering ground of G. leucogeranus in China was mainly distributed in the middle and lower reaches of the Yangtze Plain and the Yellow River Delta of the North China Plain. In these regions, the area of high-, medium- and low-suitability habitat were 17685, 60787 and 60747 km2, respectively. A total of 40 protected areas had been established in the high-suitability wintering range of G. leucogeranus in China, whereas 12 high-suitability wetlands such as Qili Lake in Anhui, Liangzi Lake in Hubei and Chenjia Lake in Jiangxi were still unprotected. The wintering grounds had shown a trend of expansion to the northeast and southeast since 2015. Considering the large-scale habitat shifts of G. leucogeranus in recent years and the frequent new wintering records in various places, we suggested that the shortage of food resources in natural habitats was the main factor driving the expansion of G. leucogeranus' wintering range. To protect G. leucogeranus more effectively, we should strengthen the restoration of natural habitats and the management of farmland habitats.


Asunto(s)
Aves , Humedales , Animales , China , Simulación por Computador , Lagos
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