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AbstractThe adaptive value of routinely laying more eggs than can be successfully fledged has intrigued evolutionary biologists for decades. Extra eggs could, for instance, be adaptive as insurance against hatching failures. Moreover, because recent literature demonstrates that sibling cannibalism is frequent in the Eurasian hoopoe (Upupa epops), producing extra offspring that may be cannibalized by older siblings might also be adaptive in birds. Here, directed to explore this possibility in hoopoes, we performed a food supplementation experiment during the laying period and a clutch size manipulation during the hatching stage. We found that females with the food supplement laid on average one more egg than control females and that the addition of a close-to-hatch egg at the end of the hatching period increased the intensity of sibling cannibalism and enhanced fledging success in hoopoe nests. Because none of the extra nestlings from the experimental extra eggs survived until fledging, these results strongly suggest that hoopoes obtain fitness advantages by using temporarily abundant resources to produce additional nestlings that will be cannibalized. These results therefore suppose the first experimental demonstration of the nutritive adaptive function of laying extra eggs in vertebrates with parental care.
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Aves , Reprodução , Animais , Feminino , Humanos , Tamanho da Ninhada , Canibalismo , IrmãosRESUMO
Food insecurity affects an estimated 691-783 million people globally and is disproportionately high in Africa and Asia. It arises from poverty, armed conflict, and climate change, among other demographic and globalization forces. This review summarizes evidence for policies and practices across five elements of the agrifood system framework and identifies gaps that inform an agenda for future research. Under availability, imbalanced agriculture policies protect primarily staple food producers, and there is limited evidence on food security impacts for smallholder and women food producers. Evidence supports the use of cash transfers and food aid for affordability and school feeding for multiple benefits. Food-based dietary guidelines can improve the nutritional quality of dietary patterns, yet they may not reflect the latest evidence or food supplies. Evidence from the newer food environment elements, promotion and sustainability, while relatively minimal, provides insight into achieving long-term impacts. To eliminate hunger, our global community should embrace integrated approaches and bring evidence-based policies and practices to scale.
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Insegurança Alimentar , Humanos , Saúde Global , Abastecimento de Alimentos/normas , Política Nutricional , Agricultura , Assistência Alimentar/organização & administraçãoRESUMO
Recent evidence suggests that individuals differ in foraging tactics and this variation is often linked to an individual's behavioural type (BT). Yet, while foraging typically comprises a series of search and handling steps, empirical investigations have rarely considered BT-dependent effects across multiple stages of the foraging process, particularly in natural settings. In our long-term sleepy lizard (Tiliqua rugosa) study system, individuals exhibit behavioural consistency in boldness (measured as an individual's willingness to approach a novel food item in the presence of a threat) and aggressiveness (measured as an individual's response to an 'attack' by a conspecific dummy). These BTs are only weakly correlated and have previously been shown to have interactive effects on lizard space use and movement, suggesting that they could also affect lizard foraging performance, particularly in their search behaviour for food. To investigate how lizards' BTs affect their foraging process in the wild, we supplemented food in 123 patches across a 120-ha study site with three food abundance treatments (high, low and no-food controls). Patches were replenished twice a week over the species' entire spring activity season and feeding behaviours were quantified with camera traps at these patches. We tracked lizards using GPS to determine their home range (HR) size and repeatedly assayed their aggressiveness and boldness in designated assays. We hypothesised that bolder lizards would be more efficient foragers while aggressive ones would be less attentive to the quality of foraging patches. We found an interactive BT effect on overall foraging performance. Individuals that were both bold and aggressive ate the highest number of food items from the foraging array. Further dissection of the foraging process showed that aggressive lizards in general ate the fewest food items in part because they visited foraging patches less regularly, and because they discriminated less between high and low-quality patches when revisiting them. Bolder lizards, in contrast, ate more tomatoes because they visited foraging patches more regularly, and ate a higher proportion of the available tomatoes at patches during visits. Our study demonstrates that BTs can interact to affect different search and handling components of the foraging process, leading to within-population variation in foraging success. Given that individual differences in foraging and movement will influence social and ecological interactions, our results highlight the potential role of BT's in shaping individual fitness strategies and population dynamics.
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Comportamento Alimentar , Lagartos , Animais , Lagartos/fisiologia , Fenótipo , Masculino , Feminino , Comportamento de Retorno ao Território Vital , AgressãoRESUMO
In birds, patterns of development of the adrenocortical response to stressors vary among individuals, types of stressors, and species. Since there are benefits and costs of exposure to elevated glucocorticoids, this variation is presumably a product of selection such that animals modulate glucocorticoid secretion in contexts where doing so increases their fitness. In this study, we evaluated hypothalamo-pituitary-adrenal (HPA) activity in first-hatched free-living seabird nestlings that engage in intense sibling competition and facultative siblicide (black-legged kittiwakes, Rissa tridactyla). We sampled 5 day old chicks (of the â¼45 day nestling period), a critical early age when food availability drives establishment of important parent-offspring and intra-brood dynamics. We experimentally supplemented parents with food ("supplemented") and measured chick baseline corticosterone secretion and capacity to rapidly increase corticosterone in response to an acute challenge (handling and 15 min of restraint in a bag). We also used topical administration of corticosterone to evaluate the ability of chicks to downregulate physiologically relevant corticosterone levels on a short time scale (minutes). We found that 5 day old chicks are not hypo-responsive but release corticosterone in proportion to the magnitude of the challenge, showing differences in baseline between parental feeding treatments (supplemented vs non-supplemented), moderate increases in response to handling, and a larger response to restraint (comparable to adults) that also differed between chicks from supplemented and control nests. Topical application of exogenous corticosterone increased circulating levels nearly to restraint-induced levels and induced downregulation of HPA responsiveness to the acute challenge of handling. Parental supplemental feeding did not affect absorbance/clearance or negative feedback. Thus, while endogenous secretion of corticosterone in young chicks is sensitive to environmental context, other aspects of the HPA function, such as rapid negative feedback and/or the ability to clear acute elevations in corticosterone, are not. We conclude that 5 day old kittiwake chicks are capable of robust adrenocortical responses to novel challenges, and are sensitive to parental food availability, which may be transduced behaviorally, nutritionally, or via maternal effects. Questions remain about the function of such rapid, large acute stress-induced increases in corticosterone in very young chicks.
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Charadriiformes , Corticosterona , Animais , Corticosterona/metabolismo , Corticosterona/sangue , Charadriiformes/fisiologia , Charadriiformes/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Estresse Fisiológico , Sistema Hipófise-Suprarrenal/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Feminino , MasculinoRESUMO
OBJECTIVES: To describe changes in home food availability during early childhood, including modified, developmentally sensitive obesogenic scores, and to determine whether home food availability is associated with food and nutrient intakes of children concurrently, over time. DESIGN: Data were drawn from the STRONG Kids 2 longitudinal, birth cohort to achieve the study objectives. Home food availability was assessed with the Home Food Inventory (HFI) and included fifteen food groups (e.g. fruit and vegetables) and three obesogenic scores (one original and two modified). Food and nutrient intakes were measured using the Block FFQ and included twenty-seven food groups and eighteen nutrients (e.g. vitamins A and C, protein). HFI and FFQ were completed by trained researchers or mothers, respectively, at 24, 36 and 48 months. Repeated-measures ANOVA and Spearman's correlations were used to achieve the study objectives. SETTING: Central Illinois, USA. PARTICIPANTS: Participants were 468 children at 24, 36 and 48 months of age. RESULTS: Availability of less nutritious foods and obesogenic foods and beverages increased as children aged, and availability of both nutritious and less nutritious foods were associated with child food and nutrient intake. The three obesogenic scores demonstrated similar, positive associations with the intake of energy, saturated fat, added sugars and kilocalories from sweets. CONCLUSION: These findings offer novel insight into changes in home food availability and associations with food and nutrient intake during early childhood. Additional attention is needed examining antecedents (e.g. built environments, purchasing behaviours) and consequences (e.g. child diet quality and weight) of home food availability.
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Dieta , Ingestão de Energia , Criança , Feminino , Humanos , Pré-Escolar , Ingestão de Alimentos , Verduras , FrutasRESUMO
Young adults (18-24 years) in universities are frequently exposed to an environment that promotes unhealthy eating behaviors. Using a validated tool, the Chinese Nutrition Environment Measurement Survey for Stores (C-NEMS-S), we assess the food availability and healthier options in a large, urban Chinese university. We employed C-NEMS-S for scoring criteria and weighting. A total of 52 on-campus canteen outlets were audited in an urban university located in Shijiazhuang City, China. General food outlets (n 43) and self-served food outlets (n 7) were further categorized into eight subtypes. Beverage outlets (n 2) were discussed separately from food outlets. C-NEMS-S scores were significantly different across food outlet types (P = 0.0024), especially between noodle and rice outlets (P = 0.0415). Food availability scores for starchy tubers (P < 0.001), dry beans (P < 0.001), vegetables (P = 0.0225), and fruits (P < 0.001) were significantly different across food outlet subtypes. Healthier options were scarce and only appeared in "grains" (n 2) and "meat and poultry" (n 2) categories. Further research on improving the accustomed audit tool and assessing university student diet quality is warranted.
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Dieta , Nível de Saúde , Adulto Jovem , Humanos , Universidades , Inquéritos Nutricionais , Verduras , Abastecimento de Alimentos , ComércioRESUMO
BACKGROUND: In Africa, approx. 675 million people were at risk of food insecurity. COVID-19 pandemic is likely to have exacerbated this situation, by damaging populations' access to and affordability of foods. This study is aimed at estimating the impacts of the COVID-19 pandemic on availability and prices of essential food commodities at 20 large markets in Ghana. METHODS: Data on food availability and food retail prices collected through weekly market-level data during the period from July 2017 to September 2020 were used in this study. We performed interrupted time-series analyses and estimated the percentage increases between the observed and predicted food prices by food group and by region to assess the impact of COVID-19 pandemic on food prices. RESULTS: As a result, the impact of COVID-19 on food availability was limited. However, the results of interrupted time-series analyses indicate a significant increase in overall mean food prices in Greater Accra, Eastern and Upper East regions. It was also found that mean price of starchy roots, tubers and plantains significantly increased across regions. DISCUSSION: The impact of COVID-19 pandemic on food availability and prices was significant but varied by food type and regions in Ghana. Continuous monitoring and responses are critical to maintain food availability and affordability.
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COVID-19 , Comércio , Abastecimento de Alimentos , Análise de Séries Temporais Interrompida , Gana/epidemiologia , Humanos , COVID-19/epidemiologia , Abastecimento de Alimentos/estatística & dados numéricos , Abastecimento de Alimentos/economia , Comércio/estatística & dados numéricos , Comércio/economia , Insegurança Alimentar/economia , Pandemias/economiaRESUMO
BACKGROUND: In 2016, a voluntary National Healthy Food and Drink Policy (hereafter, "the Policy") was released to encourage public hospitals in New Zealand to provide food and drink options in line with national dietary guidelines. Five years later, eight (of 20) organisations had adopted it, with several preferring to retain or update their own institutional-level version. This study assessed staff and visitors' awareness and support for and against the Policy, and collected feedback on perceived food environment changes since implementation of the Policy. METHODS: Cross-sectional electronic and paper-based survey conducted from June 2021 to August 2022. Descriptive statistics were used to present quantitative findings. Free-text responses were analysed following a general inductive approach. Qualitative and quantitative findings were compared by level of implementation of the Policy, and by ethnicity and financial security of participants. RESULTS: Data were collected from 2,526 staff and 261 visitors in 19 healthcare organisations. 80% of staff and 56% of visitors were aware of the Policy. Both staff and visitors generally supported the Policy, irrespective of whether they were aware of it or not, with most agreeing that "Hospitals should be good role models." Among staff who opposed the Policy, the most common reason for doing so was freedom of choice. The Policy had a greater impact, positive and negative, on Maori and Pacific staff, due to more frequent purchasing onsite. Most staff noticed differences in the food and drinks available since Policy implementation. There was positive feedback about the variety of options available in some hospitals, but overall 40% of free text comments mentioned limited choice. 74% of staff reported that food and drinks were more expensive. Low-income staff/visitors and shift workers were particularly impacted by reduced choice and higher prices for healthy options. CONCLUSIONS: The Policy led to notable changes in the healthiness of foods and drinks available in NZ hospitals but this was accompanied by a perception of reduced value and choice. While generally well supported, the findings indicate opportunities to improve implementation of food and drink policies (e.g. providing more healthy food choices, better engagement with staff, and keeping prices of healthy options low) and confirm that the Policy could be expanded to other public workplaces.
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Política Nutricional , Humanos , Nova Zelândia , Estudos Transversais , Masculino , Feminino , Adulto , Inquéritos e Questionários , Pessoa de Meia-Idade , Dieta Saudável , Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em SaúdeRESUMO
Primates are adept at dealing with fluctuating availability of resources and display a range of responses to minimize the effects of food scarcity. An important component of primate conservation is to understand how primates adapt their foraging and ranging patterns in response to fluctuating food resources. Animals optimize resource acquisition within the home range through the selection of resource-bearing patches and choose between contrasting foraging strategies (resource-maximizing vs. area-minimizing). Our study aimed to characterize the foraging strategy of a folivorous primate, Verreaux's sifaka (Propithecus verreauxi), by evaluating whether group home range size varied between peak and lean leaf seasons within a seasonally dry tropical forest in Madagascar. We hypothesized that Verreaux's sifaka used the resource maximization strategy to select high-value resource patches so that during periods of resource depression, the home range area did not significantly change in size. We characterized resource availability (i.e., primary productivity) by season at Kirindy Mitea National Park using remotely-sensed Enhanced Vegetation Index data. We calculated group home ranges using 10 years of focal animal sampling data collected on eight groups using both 95% and 50% kernel density estimation. We used area accumulation curves to ensure each group had an adequate number of locations to reach seasonal home range asymptotes. Neither 95% home ranges nor 50% core areas differed across peak and lean leaf resource seasons, supporting the hypothesis that Verreaux's sifaka use a resource maximization strategy. With a better understanding of animal space use strategies, managers can model anticipated changes under environmental and/or anthropogenic resource depression scenarios. These findings demonstrate the value of long-term data for characterizing and understanding foraging and ranging patterns. We also illustrate the benefits of using satellite data for characterizing food resources for folivorous primates.
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Comportamento de Retorno ao Território Vital , Estações do Ano , Strepsirhini , Animais , Strepsirhini/fisiologia , Madagáscar , Florestas , Comportamento Alimentar , EcossistemaRESUMO
The availability of resources varies across a species distributional range, and a low-productivity area can make a species more vulnerable. We investigated the invertebrate composition and prey choice of juvenile Atlantic salmon (Salmo salar L.) in low-productivity rivers in northeast Iceland, which is one of the species' most northerly distributions. By sampling benthic and drift invertebrate populations, we found that prey availability was similar within and between rivers. Gut content samples showed that the main prey choice for juvenile S. salar was the Chironomidae. The type of food items consumed varied across different weight groups of S. salar, with smaller juveniles having more diverse diet. S. salar did not have a selection preference for chironomids, which indicates that they were eating the highly available prey in their environment, rather than hunting high biomass items such as terrestrial invertebrates and large Dipterans. Estimates of dietary niche showed that S. salar in these low-productivity rivers relied on consuming what was most readily available, the chironomids, and that they must share resources with other salmonid species. This may be due to the low diversity of freshwater invertebrates (fewer prey options), whereas S. salar in nutrient-rich rivers could rely more on terrestrial invertebrates as an additional subsidy in their diet. In conclusion, with limited prey choices, juvenile S. salar in nutrient-poor rivers, especially in a biogeographically isolated region with low species diversity, may increase in vulnerability and decrease in adaptability to environmental change. Management methods that increase benthic prey abundance and diversity are recommended for conserving the S. salar population in a nutrient-poor river.
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Dieta , Rios , Salmo salar , Animais , Salmo salar/fisiologia , Dieta/veterinária , Islândia , Comportamento Predatório , Conteúdo Gastrointestinal , Cadeia Alimentar , Invertebrados , Chironomidae/fisiologiaRESUMO
Maintenance metabolism as the minimum energy expenditure needed to maintain homeothermy (a high and stable body temperature, T b), reflects the magnitude of metabolic machinery and the associated costs of self-maintenance in endotherms (organisms able to produce heat endogenously). Therefore, it can interact with most, if not all, organismal functions, including the behavior-fitness linkage. Many endothermic animals can avoid the costs of maintaining homeothermy and temporally reduce T b and metabolism by entering heterothermic states like torpor, the most effective energy-saving strategy. Variations in BMR, behavior, and torpor use are considered to be shaped by food resources, but those conclusions are based on research studying these traits in isolation. We tested the effect of ecological contexts (food availability and predation risk) on the interplay between the maintenance costs of homeothermy, heterothermy, and exploration in a wild mammal-the yellow-necked mouse. We measured maintenance metabolism as basal metabolic rate (BMR) using respirometry, distance moved (exploration) in the open-field test, and variation in T b (heterothermy) during short-term fasting in animals captured at different locations of known natural food availability and predator presence, and with or without supplementary food resources. We found that in winter, heterothermy and exploration (but not BMR) negatively correlated with natural food availability (determined in autumn). Supplementary feeding increased mouse density, predation risk and finally had a positive effect on heterothermy (but not on BMR or exploration). The path analysis testing plausible causal relationships between the studied traits indicated that elevated predation risk increased heterothermy, which in turn negatively affected exploration, which positively correlated with BMR. Our study indicates that adaptive heterothermy is a compensation strategy for balancing the energy budget in endothermic animals experiencing low natural food availability. This study also suggests that under environmental challenges like increased predation risk, the use of an effective energy-saving strategy predicts behavioral expression better than self-maintenance costs under homeothermy.
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The aim of the present study was to critically analyze operational definitions of food deserts and food swamps included in empirical studies published in peer-reviewed journals. A scoping review was conducted following the recommendations of the Joanna Briggs Institute and PRISMA Extension for Scoping Reviews. A search of the scientific literature was performed on August 2023 to identify empirical studies including operational definitions of food deserts and/or food swamps in three databases: Scopus, PubMed, and Scielo. A total of 932 scientific articles were identified in the three databases, from which 157 articles, published between 2002 and 2023, were included in the review. The included studies were mainly conducted in WEIRD (Western, Educated, Industrilaized, Rich and Democractic) countries. They presented a total of 107 operational definitions of food deserts and 30 operational definitions of food swamps. Large heterogeneity in the operational definitions of food deserts and food swamps was found. Published studies differed in all the elements of the operational definitions analyzed in the present work. Results stress the need for standardization and the development of more objective and multivariate continuous measures of physical food accessibility that reflect the complexity of modern food environments globally. A series of recommendations to advance food environment research are derived.
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Food availability determines the amount of energy animals can acquire and allocate to reproduction and other necessary functions. Female animals that are food limited thus experience reduced energy available for reproduction. When this occurs, females may reduce frequency of reproductive events or the number or size of offspring per reproductive bout. We assessed how maternal diet affects reproductive output in adult female Murray River short-necked turtles, Emydura macquarii, from four wetlands in Victoria. We previously found that turtle diets differ in the composition of plants and animals between our study wetlands. In this study, we tested whether differences in turtle diet composition (i.e. plants and animals) at these wetlands were associated with differences in clutch mass, individual egg mass, bulk egg composition and hatching success. We found total clutch mass increased with maternal body size at each site. At sites where filamentous green algae were scarce and E. macquarii were carnivorous, females produced smaller clutches relative to body size compared to females from sites where algae were abundant, and turtles were more herbivorous. Individual egg mass, bulk egg composition and hatching success did not differ across wetlands. Isotopic analysis revealed significant positive relationships between the carbon and nitrogen isotopes (δ13C, δ15N) of the eggs and those of the mothers, indicating that mothers allocated ratios of carbon and nitrogen isotopes to their eggs similar to those present in their tissues. Our study suggests that at sites where females are more carnivorous due to a relative absence of algae, females produce smaller clutches, but other aspects of their reproduction are not significantly impacted. The reduction in clutch size associated with differences in the availability of dietary plants and animals may have long-term consequences for E. macquarii and other freshwater turtle species that are experiencing population declines.
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Agricultural intensification and climate change are serious threats toward animal populations worldwide. Agricultural intensification reduces the heterogeneity of agricultural habitats by diminishing crop variation and destroying microhabitats, such as small woody features, whereas the effects of climate change range from the growing frequency of weather extremes to disrupted prey-predator dynamics. We collected long-term ringing data from a population of Eurasian kestrels (Falco tinnunculus) located amidst agricultural areas in western Finland during 1985-2021, which we combined with density indices of their main prey species (voles), spatial data consisting of land cover classification of kestrel territories, and weather data, to study the effects of different environmental drivers on breeding density and success. We found that the density of inhabited nests rose with vole abundance and springtime snow depth, with the overall trend of population growth being stronger in areas with more heterogeneous landscapes. Clutch size was influenced negatively by the age of male parent and landscape heterogeneity, and positively by vole abundance, with rainfall having a negative influence conditional to other variables. Likewise, the number of produced fledglings was affected by male age, but it was additionally positively associated with landscape heterogeneity and its interaction with rainfall, with greater fledgling output in heterogeneous landscapes during high precipitation. The discrepancy between factors predicting large clutches and high numbers of fledglings suggests that while kestrels do not prefer heterogeneous landscapes when prospecting for territories, heterogeneous habitats provide better circumstances for foraging during the nestling period, which ensures nestling survival, particularly during adverse environmental conditions. Therefore, breeding in areas under intense agricultural use is more suboptimal to kestrels than their territory preferences would indicate. As changing climate may reduce prey availability and heighten the probability of weather extremities, agricultural intensification may lead to weaker reproductive success in densely populated farmland habitats.
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In recent years, Hooded Vulture populations in West Africa have decreased substantially. However, in some areas within this region, the species is still relatively abundant. To find out more about the situation in West Africa, we assessed the status of Hooded Vultures in Benin, one of the countries where their status is not well known. We conducted road counts on paved and unpaved roads and along small trails over a total of 1451 km. We also conducted interviews with local abattoir watchmen, veterinarians, butchers and foresters to examine potential threats to this species. A total of 52 Hooded Vultures were counted mostly in the departments of Atacora (32) but also in Alibori (10) and Borgou (10). The relative abundance was four Hooded Vultures per 100 km, highlighting the near extirpation of this bird from Benin. A total of 49 interviews revealed that poaching for belief-based use (through shooting and traps) and decreasing food availability remain the most important threats for Hooded Vultures in northern Benin. If these threats are not mitigated, we predict the extirpation of the Hooded Vulture outside protected areas in Benin within the next two decades, possibly even sooner. Conservation measures, including awareness campaigns, and the improvement and enforcement of environmental legislation, must be urgently implemented to improve the protection of this Critically Endangered vulture species.
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This study examines patterns and trends in household food security in Bushbuckridge, Mpumalanga Province, South Africa, from 2010 to 2019. We use data from a household panel nested in the Agincourt Health and Socio- Demographic Surveillance System. Findings indicate that there have been improvements in household food security in this rural setting over the last decade. By polychoric principal component analysis, an aggregate food security index was constructed and we observed a small, yet important, proportion of households (7.8 %) that remained chronically food insecure. An ordered probit model was used to estimate the determinants of food security. Findings reveal that the observed differences in household food security status are as a result of differences in socioeconomic status. We therefore recommend that focus must be placed on identifying economic opportunities and empowering the chronically food insecure households if universal household food security is to be attained in rural South Africa and beyond.
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Golden-winged Warblers (Vermivora chrysoptera) have become rare across much of their historic breeding range and response to conservation efforts is variable. Evidence from several recent studies suggests that breeding output is a primary driver explaining responses to conservation and it is hypothesized that differences in food availability may be driving breeding output disparity between two subpopulations of the warbler's Appalachian breeding range. Herein, we studied two subpopulations: central Pennsylvania ("central subpopulation"), where breeding productivity is relatively low, and eastern Pennsylvania ("eastern subpopulation"), where breeding productivity is relatively high. To test the food-availability hypothesis in this system, we measured density of caterpillars, plasma lipid metabolites (triglycerides [TRIG; fat deposition] and glycerol [GLYC; fat breakdown]), body mass of adults males, and acquired body mass data for fledglings at 38 sites managed for nesting habitat. Consistent with our prediction, leaf-roller caterpillar density, the group upon which Golden-winged Warblers specialize, was 45× lower in the central subpopulation than the eastern subpopulation. TRIG concentrations were highest within the eastern subpopulation during breeding grounds arrival. The change in TRIG concentrations from the breeding-grounds-arrival stage to the nestling-rearing stage was subpopulation dependent: TRIG decreased in the eastern subpopulation and was constant in the central subpopulation, resulting in similar concentrations during the nestling-rearing stage. Furthermore, GLYC concentrations were higher in the eastern subpopulation, which suggests greater energy demands in this region. Despite this, adult male warblers in the eastern subpopulation maintained a higher average body mass. Finally, fledgling body mass was 16% greater in the eastern subpopulation than the central subpopulation before and after fledging. Collectively, our results suggest that poor breeding success of Golden-winged Warblers in the central subpopulation could be driven by lower availability of primary prey during the breeding season (leaf-roller caterpillars), and this, in turn, limits their response to conservation efforts.
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BACKGROUND: The number of globally food-insecure people is increasing since 2017. Sub-Saharan Africa has the highest proportion of severely food-insecure people in the world. Tigray region of Ethiopia is one of the food-insecure regions, which, over the past many decades has been affected by recurrent food insecurities. In the drought-prone rural areas of Tigray, many people are living under the condition of chronic hunger. Proper food security studies are vital for proper intervention mechanisms. Yet, previous food security studies have rarely addressed the four pillars of food security: availability, access, utilization, and stability. In this study, all components are duly considered to assess the food insecurity status in the drought-prone rural areas of Tigray, Ethiopia. Of the 34 rural districts in Tigray, 363 households from three drought-prone rural districts were studied. RESULTS: Household Food Insecurity Access Scale and Food Insecurity Experience Scale were adapted to measure the food availability, access to food, and stability components of food security; and, Household Dietary Diversity Score (HDDS), Food Consumption Score (FCS), mid-upper arm circumference, and Bitot's spot were used to analyze the food utilization aspect. Findings show that 68% of the studied community frequently ate less food than they felt they needed and 82.1% of the households have experienced hunger because of lack of food. The study rural districts were unconnected to road networks; hence, 87.9% of the elderly and 20.4% of the women and girls had no access to food markets. Regarding the food utilization, 81.5% of the studied households had poor FCS; and the average HDDS and FCS for the study areas were 2.47 and 18.9, respectively. The prevalence of Global acute malnutrition, severe acute malnutrition (SAM), and moderate acute malnutrition (MAM) for 6-59 months of age children in the study areas were 50.3, 4.2, and 46.1%, respectively. More notably, the prevalence of SAM for children from the food-insecure households was 21.2%. The prevalence of MAM for pregnant and lactating women (PLW) in the study areas was 59.5. Further, the prevalence of Bitot's spot among 6-59 months of age children was 1.9%. On the other hand, all the rural households had anxiety about their future food demands. CONCLUSION: The rural households living in the studied areas were critically food-insecure. All the measurements implied that the food insecurity situation in the study areas was unacceptably worrisome and life-threatening. This calls for an instant action to avert the occurrence of famine and starvation in the drought-prone rural areas of Tigray region. Thus, interventions should primarily target the vulnerable rural people and need to be planned based on attaining food availability first rather than concurrently addressing all components of food security. Further, due emphasis should be given to diversifying livelihood strategies of the vulnerable villagers.
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Secas , Características da Família , Insegurança Alimentar , População Rural , Humanos , Etiópia , Feminino , População Rural/estatística & dados numéricos , Adulto , Masculino , Adulto Jovem , Adolescente , Pessoa de Meia-Idade , Pré-Escolar , Abastecimento de Alimentos/estatística & dados numéricos , Lactente , Criança , Fome , Segurança Alimentar/estatística & dados numéricosRESUMO
The COVID-19 pandemic triggered a global crisis with unanticipated and diverse consequences. Moreover, the pandemic has considerably impacted food dynamics in low- and middle-income countries (LMICs), where food systems have already been challenged. These countries also have the highest share of the world's malnourished and food insecure. Therefore, this paper aims to analyze the pandemic's impact on food security dimensions (availability, accessibility, utilization, and stability), with a special emphasis on LMICs. According to the results, the pandemic immediately impacted food security by limiting food production and availability. It also had an indirect impact when lockdowns and other confinement measures (e.g., social distancing, movement restrictions) made it more difficult for individuals to access food and maintain a healthy, balanced diet (cf. food utilization). Indeed, with rising unemployment and poverty, access to food has been the most critically undermined aspect of food security. At the utilization level, COVID-19 adversely influences the nutritional state of both individuals and countries, leading to an increase in all forms of malnutrition. Finally, the impact of COVID-19 on the stability dimension is dependent on the length of the pandemic as well as the effectiveness with which recovery plans are followed to ensure universal vaccine availability, among other factors. As a result, including agricultural and food systems in recovery strategies is crucial to mitigating the pandemic's long-term effects on food security.
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An understanding of thermal limits and variation across geographic regions is central to predicting how any population may respond to global change. Latitudinal clines, in particular, have been used to demonstrate that populations can be locally adapted to their own thermal environment and, as a result, not all populations will be equally impacted by an increase in temperature. But how robust are these signals of thermal adaptation to the other ecological challenges that animals commonly face in the wild? Seasonal changes in population density, food availability, or photoperiod are common ecological challenges that could disrupt patterns of thermal tolerance along a cline if each population differentially used these signals to anticipate future temperatures and adjust their thermal tolerances accordingly. In this study, we aimed to test the robustness of a cline in thermal tolerance to simulated signals of seasonal heterogeneity. Experimental animals were derived from clones of the Australian water flea, Daphnia carinata, sampled from nine distinct populations along a latitudinal transect in Eastern Australia. We then factorially combined summer (18 h light, 6 h dark) and winter (6 h light, 18 h dark) photoperiods with high (5 million algal cells individual-1 day-1) and low (1 million algal cells individual-1 day-1) food availabilities, before performing static heat shock assays to measure thermal tolerance. We found that the thermal tolerances of the clonal populations were sensitive to both measures of seasonal change. In general, higher food availability led to an increase in thermal tolerances, with the magnitude of the increase varying by clone. In contrast, a switch in photoperiod led to rank-order changes in thermal tolerances, with heat resistance increasing for some clones, and decreasing for others. Heat resistance, however, still declined with increasing latitude, irrespective of the manipulation of seasonal signals, with clones from northern populations always showing greater thermal resistance, most likely driven by adaptation to winter thermal conditions. While photoperiod and food availability can clearly shape thermal tolerances for specific populations, they are unlikely to overwhelm overarching signals of thermal adaptation, and thus, observed clines in heat resistance will likely have remained robust to these forms of seasonal heterogeneity.