Diet In Season Research Articles

Supplementation of seasonal natural resources with year‐round anthropogenic resources by coyotes in natural fragments within a high‐density urban area

Coyotes Canis latrans in urban landscapes provide important food web functions and ecological services but can also trigger human‐wildlife conflict when their diet includes anthropogenic resources or domestic pets. As adaptable omnivores, coyotes adjust their diet to their environment, routinely switching among food items to accommodate spatial and seasonal differences in availability. To evaluate the coyote's potential impacts within the food web of urban Long Beach, California where human‐wildlife conflict involving coyotes may occur, we analyzed 115 scat samples collected once every two weeks from four open space fragments inside the urban matrix. We hypothesized that differences in scat composition would correlate with seasonal and site differences, with greater use of anthropogenic resources during the dry season supplementing lower prey availability, and with greater consumption of wild mammal prey during the wet season when fruiting plants are less abundant. We found coyote diet was predominately composed of natural prey and vegetation year‐round, with seasonal variation. Mammals made up more of coyote diet in the wet season than the dry, while invertebrates and vegetation were more prevalent in dry season scats. Coyotes relied on rabbits as their main prey year‐round across all sites. Domestic cats Felis catus were the third most common individual prey species found in coyote scats, occurring in 14% of scat samples in both seasons. Coyotes also supplemented seasonally available natural food sources with anthropogenic resources, which occurred in 13% of coyote scats overall with no significant seasonal variation. While rabbits appeared in scat from all sites, the occurrence of invertebrates, small mammals, and vegetation in scats varied between sites. While there is a potential for human‐wildlife conflict in coyote's consumption of feral or domestic cats, coyotes may also be providing an ecological service by reducing cats in natural habitat fragments.

Feeding Features of the Nine-Spined Stickleback Pungitius pungitius (Gasterosteidae) In Water Bodies of the North-West of Russia

The diet of the nine-spined stickleback Pungitius pungitius has been studied in two water bodies in the north-west of Russia: in the subarctic lake Krivoe (Karelia) and the estuary of the Neva River (Leningrad Oblast). Diptera larvae (Chironomidae, Ceratopogonidae, Simuliidae, and Limoniidae) and planktonic crustaceans formed the basis of the food bolus of fish; however, their abundance and weight ratios differed in the studied water bodies. The seasonal changes of the dominant groups of food objects of the stickleback of Lake Krivoe have been revealed. Additionally to invertebrates and fish eggs, which form the basis of the stickleback diet in winter season, aquatic mosses as well as filamentous and diatom algae present in the fish diet in summer. The comparison of the nitrogen isotope composition of the muscles of stickleback, perch, and invertebrates shows that the stickleback of Lake Krivoe occupies the third trophic level, approaching predatory fish in δ15N values (5.2–8.6‰). A specific feature of the diet patterns of P. pungitius is the transition from a diverse diet of the summer–autumn period to a monotrophic animal diet (chironomid larvae and fish eggs) of the under-ice winter–spring period.

Effects of Different Dietary Protein Level on Growth Performance, Rumen Fermentation Characteristics and Plasma Metabolomics Profile of Growing Yak in the Cold Season.

This experiment was aimed to compare the effects of two diets with different protein content on the growth performance, immune indexes, rumen fermentation characteristics and plasma metabolomics of growing yak in the cold season. A total of 24, 2-year-old healthy yaks with similar body weight (142.9 ± 3.56 kg) were randomly allocated to two isoenergetic diets with different protein content (10 vs 14%) according to a non-paired experimental design, and the protein of the diets was increased by increasing soybean meal, rapeseed meal and cottonseed meal. The growth performance experiment lasted 56 days. Four days before the end of the growth experiment, the digestion trial was conducted, and the rumen fluid and plasma was collected for measurement. The results showed that the average daily feed intake (p < 0.001) and average daily gain (p = 0.006) of yak fed a high-protein diet was significantly greater, while the feed conversion ratio was lower (p = 0.021) than that of yaks fed a low-protein diet. Plasma aspartate aminotransferase (p = 0.002), alanine aminotransferase (p < 0.001), malondialdehyde (p = 0.001), tumor necrosis factor-α (p = 0.032) and interferon-γ (p = 0.017) of the high-protein group were significantly lesser, whereas superoxide dismutase (p = 0.004) and interleukin-2 (p = 0.007) was significantly greater than that of the low-protein group. The rumen microbial crude protein (p < 0.047) and crude protein digestibility (p = 0.015) of yak fed a high-protein diet was significantly greater than that of the low-protein group. The metabolomics results showed that yaks fed a high-protein diet were elevated in protein digestion and absorption, arginine and proline metabolism, tryptophan metabolism, purine metabolism, butanoate metabolism, taste transduction, pyrimidine metabolism, pantothenate and CoA biosynthesis, glutathione metabolism and renin secretion pathways. It is concluded that a high-protein diet in the cold season can promote rumen microbial crude protein synthesis, enhance antioxidant and immune function and promote growth performance of yaks.

Seasonal Variation in Terrestrial Invertebrate Subsidies to Tropical Streams and Implications for the Feeding Ecology of Hart’s Rivulus (Anablepsoides hartii)

Terrestrial invertebrates are important subsidies to fish diets, though their seasonal dynamics and importance to tropical stream consumers are particularly understudied. In this year-round study of terrestrial invertebrate input to two Trinidadian headwater streams with different forest canopy densities, we sought to (a) measure the mass and composition of terrestrial inputs with fall-in traps to evaluate the influences of seasonality, canopy cover, and rainfall intensity, and; (b) compare terrestrial and benthic prey importance to Anablepsoides hartii (Hart’s Rivulus), the dominant invertivorous fish in these streams, by concurrently measuring benthic and drifting invertebrate standing stocks and the volume and composition of invertebrates in Rivulus guts throughout the year. The biomass of terrestrial invertebrate fall-in was 53% higher in the wet versus dry season; in particular, ant input was 320% higher. Ant biomass fall-in also increased with the density of canopy cover among sampling locations within both streams. Greater precipitation correlated with increased ant inputs to the more open-canopied stream and increased inputs of winged insects in the more closed canopy stream. Concurrently, the biomass of benthic invertebrates was reduced by more than half in the wet season in both streams. We detected no differences in the total volume of terrestrial prey in Rivulus diets between seasons, though ants were a greater proportion of their diet in the wet season. In contrast, benthic prey were nearly absent from Rivulus diets in the wet season in both streams. We conclude that terrestrial invertebrates are a substantial year-round prey subsidy for invertivores in tropical stream ecosystems like those we studied, which may contrast to most temperate streams where such terrestrial inputs are significantly reduced in the cold season. Interestingly, the strongest seasonal pattern in these tropical streams was observed in benthic invertebrate biomass which was greatly reduced and almost absent from Rivulus diets during the wet season. This pattern is essentially the inverse of the pattern observed in many temperate streams and highlights the need for additional studies in tropical ecosystems to better understand how spatial and temporal variation in terrestrial subsidies and benthic prey populations combine to influence consumer diets and the structure of tropical stream food webs.

Effect of grass-diet and grass-legume-diet manure applied to planting holes on smallholder maize production in Rwanda

• 5 t ha −1 of micro-dosed manure approx. doubled the yields compared to the control. • Micro-dosed NPK (70 kg N ha −1 ) meanwhile increased yields 3–4 times. • Legume supplemented diet increased manure quality, and also yield season 4. Animal manure provides plant nutrients and also affects soil nutrient availability, pH buffering and soil physical properties through its contribution to soil organic matter pools. However, the quality and quantity of manure are often low on smallholder farms in sub-Saharan Africa and the initial effect of manuring on crop yield may be small or even negative. In a two-factorial experiment over four seasons in southern Rwanda, the fertiliser value to a maize crop of manures produced by cattle fed a basal diet of only Chloris gayana grass or a mixed C. gayana-Acacia angustissima diet was compared with that of NPK 17−17−17 and no fertiliser. The potential liming effect of the manures was also evaluated through inclusion (or not) of travertine as the second factor. All amendments were applied only to maize planting holes. The crop failed in season 1 due to drought, but manure application (5 t ha −1 ) approximately doubled maize yield compared with the unfertilised control during seasons 2–4, while NPK (70 kg N ha −1 ) increased yield by 3- to 4-fold, with corresponding improvements in crop performance indicators. The mixed diet increased manure quality and maize yield compared with the grass diet in season 4. Liming showed a consistent tendency to improve crop performance indicators and yield, but significant differences were only identified in some cases, possibly because the pH increase was small. The results suggest that in regions where manure availability is limiting, application of reduced rates only to planting holes may be an efficient technology. Enhanced animal feed can result in higher quality manure, and ultimately increase crop yield, if nutrient losses during manure handling and storage can be limited.

Regulation of Peroxisome Proliferator-Activated Receptor Pathway During Torpor in the Garden Dormouse, Eliomys quercinus.

Differential levels of n-6 and n-3 essential polyunsaturated fatty acids (PUFAs) are incorporated into the hibernator’s diet in the fall season preceding prolonged, multi-days bouts of torpor, known as hibernation. Peroxisome proliferator-activated receptor (PPAR) transcriptional activators bind lipids and regulate genes involved in fatty acid transport, beta-oxidation, ketogenesis, and insulin sensitivity; essential processes for survival during torpor. Thus, the DNA-binding activity of PPARα, PPARδ, PPARγ, as well as the levels of PPARγ coactivator 1α (PGC-1α) and L-fatty acid binding protein (L-FABP) were investigated in the hibernating garden dormouse (Eliomys quercinus). We found that dormice were hibernating in a similar way regardless of the n-6/n-3 PUFA diets fed to the animals during the fattening phase prior to hibernation. Further, metabolic rates and body mass loss during hibernation did not differ between dietary groups, despite marked differences in fatty acid profiles observed in white adipose tissue prior and at mid-hibernation. Overall, maintenance of PPAR DNA-binding activity was observed during torpor, and across three n-6/n-3 ratios, suggesting alternate mechanisms for the prioritization of lipid catabolism during torpor. Additionally, while no change was seen in L-FABP, significantly altered levels of PGC-1α were observed within the white adipose tissue and likely contributes to enhanced lipid metabolism when the diet favors n-6 PUFAs, i.e., high n-6/n-3 ratio, in both the torpid and euthermic state. Altogether, the maintenance of lipid metabolism during torpor makes it likely that consistent activity or levels of the investigated proteins are in aid of this metabolic profile.

Seasonal variation in the gut microbiota of rhesus macaques inhabiting limestone forests of southwest Guangxi, China.

Data on the gut microbiota of animals can provide new insights into dietary ecology of hosts, consequently assisting in understanding their adaptation strategy and evolutionary potential. We studied the gut microbiota composition and function of the wild rhesus macaques (Macaca mulatta) using 16S rRNA sequencing method. Our results revealed that the gut microbiota of the wild rhesus macaques was dominated by Firmicutes, Bacteroidetes, and Spirochaetes. Diversity and richness of gut microbiota were higher during the dry season than the rainy season. Specifically, higher proportions of Firmicutes, Tenericutes, Cyanobacteria, and unclassified bacteria at the phylum level and more Coprococcus at the genus level were detected in the dry season. Predictive functional analysis showed that pathways associated with carbohydrate metabolism and drug resistance (antimicrobial and antineoplastic) were richer in the dry season. These seasonal differences in microbiota could be due to their heavier dependence on leaf-based diet in the dry season. Additionally, macaques in limestone forests had a higher percentage of Spirochaetes, probably suggesting that the proportion of fruits in dietary composition also play an important role in the gut microbiota. We concluded that diet was strongly linked to the diversity, composition, and function of the gut microbiota in the wild groups of rhesus macaques living in the limestone forest, highlighting the importance of diet in the gut microbiota of macaques and the need to conduct further study on the adaptation strategy in response of environmental changes in the ground of gut microbiota.

The diet of a forest-dependent frog species, Odorrana morafkai (Anura: Ranidae), in relation to habitat disturbance

Abstract While deforestation is one of the greatest drivers of biodiversity loss, our understanding of the effects of habitat modification on species is limited. We investigated the diet of a forest-dwelling frog species, Morafka’s frog (Odorrana morafkai), in a highland forest in Vietnam in relation to habitat disturbance, sex and season. We surveyed the species at 45 sites in forest of varying disturbance and examined its diet using stomach flushing, estimating prey availability via trapping. We detected significantly fewer O. morafkai in highly disturbed habitats compared to moderately disturbed or non-disturbed habitats. We revealed that O. morafkai is a dietary generalist, identifying 28 prey types, primarily invertebrates. Prey composition, the number of prey items per stomach and prey volume per stomach did not vary between disturbance levels. Diet did not vary significantly between sexes, except that females had a higher prey volume. Prey composition in the species varied between seasons, with Coleoptera and Orthoptera dominating the diet in the rainy season and Lepidoptera in the dry season. The number of prey items per stomach and prey volume were significantly higher in the rainy season. There was a significant correlation between prey availability and diet composition. The low number of O. morafkai detected in highly disturbed habitats suggests that this habitat may not be optimal for the species, despite having a generalist feeding strategy and presumed high mobility. This study provides a window into the impact of an increasing threat, habitat disturbance, on forest-dependent amphibian species.

Production Diversity Is Not Associated with Women’s Dietary Diversity After Controlling for Wealth and Participation in an Agriculture Intervention in Tanzania (P10-031-19)

ObjectivesFarm production diversity has long thought to be a primary driver of dietary diversity. Few studies have explored the drivers of dietary diversity among women, who are often vulnerable to sub-optimal diets. We therefore investigated how production diversity affects women’s dietary diversity in smallholder farming communities in rural Tanzania. Specifically, we hypothesized that women in households with greater farm production diversity would have higher dietary diversity. MethodsFemale farmers (n = 462) were surveyed on agricultural practices in 2018 and their diet in the subsequent harvest season as a part of the Singida Nutrition and Agroecology Project (SNAP-Tz). SNAP-Tz is a cluster randomized effectiveness trial of a participatory agroecology and nutrition intervention. We estimated the impact of production diversity (crop species richness, range: 1–10) on women’s dietary diversity (Minimum Dietary Diversity for Women, range: 1–10) using linear regression analysis with Stata15, controlling for geographic clustering and other known covariates of women’s dietary diversity. ResultsFarm production diversity was positively associated with women’s dietary diversity after controlling for household size, age, and women’s occupation (b = 0.15, P < 0.01). However, this association was not significant (b = 0.068, P = 0.18) after additionally controlling for household wealth and participation in the intervention. ConclusionsContrary to our hypothesis, women living in households with higher production diversity did not have more diverse diets when controlling for other covariates of dietary diversity, i.e., household wealth and participation in the participatory agroecology intervention. Modifiable determinants of women’s dietary diversity are an important area for future exploration. Comparing and contrasting the role of production diversity here to that in other settings will be fruitful. Funding SourcesThis study is funded by the McKnight Foundation. Sera L. Young was supported by the National Institutes of Health (K01 MH098902).

Seasonal shifts in habitat use and diet by eland confined in a small fenced reserve

AbstractLarge‐scale environmental changes create challenges for conservation of wildlife, particularly in fenced, insular protected areas where many wildlife populations persist. Moreover, large mammalian herbivores inhabiting spatially and temporally heterogeneous environments face the challenge of securing highly variable forage resources. Mixed feeders like the eland (Taurotragus oryx) can switch between browse and grass, but the cues that elicit that switch are not well understood. We investigated the seasonal diet shift of eland confined to a small fenced reserve and the role of greenness to elicit that shift. Eland changed from a diet in the wet season, consisting of grasses and browse found in woodland and grassland vegetation types, to a diet in the dry season dominated by the greenest browse species still available in woodland vegetation types, as greenness of dry season forage decreased. Our results suggest that eland switch from browsing to grazing in response to phenophase of the grass sward, which could explain the varying selection of grasses versus browse observed across the species range.

Seasonal changes in diet and chemical defense in the Climbing Mantella frog (Mantella laevigata).

Poison frogs acquire chemical defenses from the environment for protection against potential predators. These defensive chemicals are lipophilic alkaloids that are sequestered by poison frogs from dietary arthropods and stored in skin glands. Despite decades of research focusing on identifying poison frog alkaloids, we know relatively little about how environmental variation and subsequent arthropod availability impacts alkaloid loads in poison frogs. We investigated how seasonal environmental variation influences poison frog chemical profiles through changes in the diet of the Climbing Mantella (Mantella laevigata). We collected M. laevigata females on the Nosy Mangabe island reserve in Madagascar during the wet and dry seasons and tested the hypothesis that seasonal differences in rainfall is associated with changes in diet composition and skin alkaloid profiles of M. laevigata. The arthropod diet of each frog was characterized into five groups (i.e. ants, termites, mites, insect larvae, or ‘other’) using visual identification and cytochrome oxidase 1 DNA barcoding. We found that frog diet differed between the wet and dry seasons, where frogs had a more diverse diet in the wet season and consumed a higher percentage of ants in the dry season. To determine if seasonality was associated with variation in frog defensive chemical composition, we used gas chromatography / mass spectrometry to quantify alkaloids from individual skin samples. Although the assortment of identified alkaloids was similar across seasons, we detected significant differences in the abundance of certain alkaloids, which we hypothesize reflects seasonal variation in the diet of M. laevigata. We suggest that these variations could originate from seasonal changes in either arthropod leaf litter composition or changes in frog behavioral patterns. Although additional studies are needed to understand the consequences of long-term environmental shifts, this work suggests that alkaloid profiles are relatively robust against short-term environmental perturbations.

Food tree species consumed during periods of food shortage in Burkina Faso and their threats

Aim of study: Edible products from tree species were identified in Burkina Faso and their contribution to the diet in the lean season was assessed. The main threats affecting most consumed food tree species were also documented.Area of study: Six villages across two phytogeographic regions of Burkina FasoMaterial and methods: Focus group discussions and semi-structured interviews, including a 7-day dietary intake recall targeting women; semi-structured interviews targeting key male informants.Main results: The number of edible tree products consumed was found to vary according to phytogeographic region and ethnic group. A few tree species played a disproportionally greater role in the diet and were characterized by very high frequency of consumption by the majority of households in both phytogeographic regions and across ethnicities: Adansonia digitata, Parkia biglobosa and Vitellaria paradoxa. These species are not critically endangered at country level but they are perceived as scarcely available at local level. Considering that the main threats on priority tree species (fires, drought, pest and diseases) vary across regions, to maintain sustainable sources of nutrients in the landscape, mitigation measures should be diversified and adapted to local pressures.Research highlights: Priorities for conservation are emerging clearly, but research efforts should also target underutilized tree species for their potential to diversify nutrient-poor diets.

Growth and wool production of sheep reared at highland of Nepal

Sheep farmers lived in high altitude of Nepal have limited options of supplying roughages in winter season which is resulting severe feed deficit in these periods. Quality roughages like hay and other dried cereal stalks are not sufficiently available in the areas to mitigate the feed deficit in dry harsh winter. Therefore, the study was conducted to evaluate the effects of commonly practiced feeding system on growth and wool production of sheep in winter season. The research was performed at Sheep and Goat Research farm, Jumla, Nepal which is located at 2700 meters above sea level. The animals were supplied with three different rations viz (i) adlibitum oat hay with concentrate feed @ 1% of body weight;(ii) adlibitum conventional hay with concentrate feed @1% of body weight, and (iii) grazing in moderate pasture with concentrate feed @ 1% of body weight. The differences among the treatments were found significant ((p&lt;0.05) changes in terms of average daily weight gain and total weight gain, while wool length and wool production were not significantly different (p&gt;0.05) among the treatments. The treatment of feeding oat hay with concentrate @ 1% of body weight had yielded highest body weight gain. The result of the study revealed that feeding oat hay was more profitable in comparison to conventional system of grazing and feeding conventional hay. Inclusion of oat hay on the sheep diet in dry harsh winter season could make substantial improvement in the body weight gain of the sheep in the high altitude of Nepal.Bang. J. Anim. Sci. 2017. 46 (3): 159-163

Feeding behavior and activity budget of the southern yellow-cheeked crested gibbons (Nomascus gabriellae) in a lowland tropical forest.

The southern yellow-cheeked crested gibbon (Nomascus gabriellae), an endangered species native to Vietnam and Cambodia, lives exclusively in undisturbed tropical forests and depends primarily on ripe fruit for food. Although this species is highly threatened, its ecology and conservation status remain relatively unknown. In order to understand how this heavily frugivorous primate adapts to the seasonal fluctuation of fruit resources in the forest, we collected feeding behavior and ranging activity data on one group of southern yellow-cheeked crested gibbons in Cat Tien National Park, Vietnam, over 1-year period. We compared these data to information on phenological patterns at the site gleaned during a prior study. We found that the gibbons gathered most of their food from 69 different plant species and also consumed insects and bird eggs. Fruits were the main dietary item (43.3%), followed by leaves (38.4%), flowers (11.6%), and other plant parts (6.0%). A significant seasonal shift in diet was observed; fruit generally dominated the diet in the rainy season and leaves in the dry season. The gibbons often started daily activities very early (05:10 am) in the morning and also ended quite early (16:45 pm) in the afternoon. Socializing was concentrated in the early morning, feeding had a bimodal pattern of high activity levels in mid-morning and mid-afternoon, and resting was most intense at the earliest and latest hours of the day and at midday, with proportionally less time used for traveling at these times. Averaged over the annual cycle, the gibbons spent 45% of their time feeding, 31.9% resting, 14.1% traveling, and 9.0% socializing. The percentage of time allocated to different activities varied significantly across months and between the dry and rainy seasons. Monthly variation in the activity budget was strongly related to changes in diet. In the rainy season, when the gibbons ate a higher percentage of fruit, they decreased their feeding time, while increasing traveling time in search of food; conversely, in the dry season, when they fed on a higher percentage of leaves, they decreased traveling time. Overall, our results show that the activity budget and diet of the southern yellow-cheeked crested gibbon are associated with seasonal shifts in climate. This study provides information relevant to the conservation and management of this endangered species by identifying important habitat conditions for reintroducing captive animals into the wild and providing insight into dietary needs, which may be relevant to the maintenance of animals in rescue centers.

Diet of &lt;i&gt;Agonostomus monticola&lt;/i&gt; (Pisces: MugHidae) in the Río Ayuquila, Sierra de Manantlán Biosphel'c Reserve, México

Se cuantificó la dieta del pez Agonostomus montícola en 1990 en México. La dieta es oportunista e incluyó 32 familias de animales y nueve de plantas, pero dominó el alimento de origen animal, especialmente en individuos de 151-300 mm de longitud.

Aspects of the ecology of the tortoiseKinixys nogueyi(Lataste, 1886) in Togo and Nigeria (West Africa)

In this study, the sex ratio, habitat use, and diet of free-ranging Kinixys nogueyi are examined. Sex ratio and habitat use were examined in Togo and Nigeria (West Africa), and food habits only in Nigeria. Sex ratios were equal in both populations. Tortoises had clear habitat preferences in both countries, and the Nigerian population exhibited seasonal but not inter-sexual differences in habitat selection. The present study demonstrated that this species inhabits not only Guinea savannahs and relatively wet savannahs, as already reported in the literature, but also rainforest patches and hilly forests, especially in Togo. Food remains in the feces of Nigerian specimens belonged to plants and fungi as well as to animals, with inter-seasonal but not inter-sexual differences in dietary composition. In particular, there was a significant shift from a diet based mostly on animal food in the dry season towards a mainly vegetarian diet in the wet season.

Food Habits of Indian Grey Hornbill Ocyceros birostris in Sathyamangalam forest Division, Eastern Ghats, India

The foraging ecology of Indian Grey Hornbill Ocyceros birostris was studied in Sathyamangalam Forest Division, Eastern Ghats, from 2006 to 2008. Its diet in the breeding season was assessed by 720 hours of direct observations of food deliveries to 10 different nest inmates and by nest midden analysis. Observations at nest holes revealed that males visited nests an average of 16 times per day, and the food items delivered to the nest inmates (female and chicks) included both plant (63.7%) and animal matter (36.3%). Fleshy fruits of 14 species were delivered, and the animal matter was mainly insects (99%). Seeds collected from the nest middens on analysis showed the presence of 26 fruit species of 16 plant families. Food habits of this hornbill during the non-breeding season were assessed by walking along transects and observing foraging activities. Of the 3,086 feeding observations obtained, 83% were on fruits and the rest were on leaves (8.8%), insects (7.7%), and flowers (0.5%). Of the 38 fruit species eaten, Ficus spp. constituted 25.3% of the non-breeding season fruit diet. In all, fruits of 41 species of 21 families were recorded in the diet. The study revealed that both fig and non-fig species are important for the survival of the Indian Grey Hornbill in the Eastern Ghats.

A desire for weight loss in season increases disordered eating behaviour risk and energy deficiency in athletes

Objective: The objective was to explore eating behaviour, body image and energy status in female university team sport athletes.Design: This was a cross-sectional, descriptive study design.Setting: The setting was North-West University, Potchefstroom, South Africa.Subjects: Subjects were top university female field hockey and netball player volunteers, aged 18-30 years (n = 22), and recruited during their sport season.Outcome measures: Athletes completed demographic, health and sport, and body weight questionnaires. The Eating Disorder Inventory and the Three-Factor Eating Questionnaire’s cognitive dietary restraint subscale were used to measure disordered eating behaviour. Body composition was measured with dual-energy X-ray absorptiometry. Estimated energy availability (estEA) was determined from a three-day diet and exercise record.Results: Fifteen (68%) athletes were identified with an increased risk of disordered eating. Sixteen (73%) were dieting. A low estEA (24 ± 12 kcal/kg fat-free mass/day) was found in 59% of the athletes, of whom 85% (11/13) had increased risk of disordered eating. A significantly positive (p-value < 0.05) association was found between cognitive dietary restraint and drive for thinness (r = 0.4) and body weight (r = 0.5). A negative association was found between desired weight loss (r = −0.5), energy intake (r = −0.5) and estEA (r = −0.7).Conclusion: Nonlean build athletes who diet in season are at increased risk of disordered eating behaviour and low energy availability.

Seasonal Diet of the Otter ( Lutra lutra ) On the Alazani River (Georgia)

The seasonal diet of the otter ( Lutra lutra ) was studied on Alazani river in eastern Georgia using scat analysis. The frequency of occurrence (FO) of prey items and, for fish species, biomass consumed (BC) were estimated. Fish and amphibians made the bulk of the otter diet in the study area (49.8-30.0% FO and 23.6-36.2% FO, respectively). Reptiles were also important in otter diet (11.5% and 13.4%). Mammals, birds, insects, mollusks and crayfish were of minor importance. Crucian carp (Carassius carassius) and common carp were the most important fish in the otter diet. Among amphibians, only Rana ridibunda were found; among reptiles, only dice snake and grass snake were found in otter spraints. All mammals preyed upon by otters were rodents; mice (69% of all mammals) and muskrat (31%). Water beetles ( Dytiscidae ) and grasshoppers ( Acridoidea ) were the main group of insects consumed by otters. Seasonal food niche breadth change was expressed strongly (B A = 0.260 in cold season vs. B A = 0.492 in the warm season). Crucian carp predominated in the diet in both warm (37.9% BC and 52.0% FO, respectively) and cold season (90.4% BC and 82.0% FO, respectively). C. idella and S. glanis were found during the warm season but almost disappeared from the otter diet in the cold season. Rutilus rutilus and Hypophthalmiehthys molitrix were of minor importance in both seasons. Download the complete issue.

Seasonal diet and prey preference of the African lion in a waterhole-driven semi-arid savanna.

Large carnivores inhabiting ecosystems with heterogeneously distributed environmental resources with strong seasonal variations frequently employ opportunistic foraging strategies, often typified by seasonal switches in diet. In semi-arid ecosystems, herbivore distribution is generally more homogeneous in the wet season, when surface water is abundant, than in the dry season when only permanent sources remain. Here, we investigate the seasonal contribution of the different herbivore species, prey preference and distribution of kills (i.e. feeding locations) of African lions in Hwange National Park, Zimbabwe, a semi-arid African savanna structured by artificial waterholes. We used data from 245 kills and 74 faecal samples. Buffalo consistently emerged as the most frequently utilised prey in all seasons by both male (56%) and female (33%) lions, contributing the most to lion dietary biomass. Jacobs’ index also revealed that buffalo was the most intensively selected species throughout the year. For female lions, kudu and to a lesser extent the group “medium Bovidae” are the most important secondary prey. This study revealed seasonal patterns in secondary prey consumption by female lions partly based on prey ecology with browsers, such as giraffe and kudu, mainly consumed in the early dry season, and grazers, such as zebra and suids, contributing more to female diet in the late dry season. Further, it revealed the opportunistic hunting behaviour of lions for prey as diverse as elephants and mice, with elephants taken mostly as juveniles at the end of the dry season during droughts. Jacobs’ index finally revealed a very strong preference for kills within 2 km from a waterhole for all prey species, except small antelopes, in all seasons. This suggested that surface-water resources form passive traps and contribute to the structuring of lion foraging behaviour.