Use Of Food Resources Research Articles

Report on mandibular remains of Notiomastodon platensis (Mammalia, Proboscidea) and review of its fossil record in the paleoecological context of Valle del Cauca, Colombia

The Proboscidea were very prominent in South American ecosystems during the Pleistocene and part of the Holocene. Specifically, in Valle del Cauca (Colombia), fossils of these large mammals have been found, reflecting an abundant presence in the region. In this work, a mandibular fragment with a complete last molar (m3) is reported, found near the bed of the Cauca River, in the Juanchito municipality of Santiago de Cali. According to the morphological features of the specimen, it is proposed that the remains belong to the proboscidean Notiomastodon platensis. This study emphasizes the large geographical distribution of this proboscidean in South America, including the Valle del Cauca, and provides new information on its presence in Colombia. In a paleoecological context, this work supports a generalist condition based on the use of food resources associated with the tropical dry forest during the processes of glacial and interglacial fluctuation that this type of ecosystem experienced during the Pleistocene epoch and that led to various changes in habitat aridity, fragmentation, and heterogeneity. Keywords: Notiomastodon, Quaternary, paleoecology, megafauna, South America.

The relative importance of suspended versus benthic food resources to freshwater mussels in central Texas, U.S.A.

Abstract As unionid mussels continue to decline in North America much remains unknown regarding their primary food resources and feeding relationships. Our objective was to investigate spatial, temporal, intra‐ and interspecific variation in food resource use. In this study, we quantified stable C (δ13C) and stable N (δ15N) isotopic signatures for five mussel species and their potential food resources across four catchments and three seasons in central Texas, U.S.A. Across all species and sites, Bayesian mixing models suggest C derived from coarse particulate organic matter (CPOM; bulk detrital leaf packs) contributed on average 51% to the mussel diet and C derived from suspended particulate organic matter contributed 41% on average to the mussel diet. Mussel stable isotope signatures exhibited minimal variation across species within a site, but significant differences across sites and seasons. Although significant differences in food source contributions were observed between sites and species, differences were relatively small and either CPOM or suspended particulate organic matter were consistently the primary food resource. Mussels were potentially consuming microbial biofilms associated with CPOM pools, but preferential assimilation of detrital biofilms remains to be quantified. Carbon:nitrogen ratios of mussel soft tissue varied seasonally with summer ratios approximately 3 times higher on average than spring and autumn ratios, which is suggestive of poor food quality and thermal stress during the summer. Some species had significant positive relationships between isotopic ratios and shell length, which indicates changes in food resource incorporation with increasing mussel size. Together these data suggest the C in mussel tissues was of benthic and suspended origin. These findings provide further evidence that mussels effectively exploit benthic in addition to planktonic food resources which emphasises the need to maintain riparian habitats and allochthonous inputs.

Seasonal variations in the composition and functional profiles of gut microbiota reflect dietary changes in plateau pikas.

Seasonal variations in gut microbiota of small mammals and how they are influenced by environmental variables are relatively poorly understood. We sampled 162 wild plateau pikas (Ochotona curzoniae) in 4 seasons over 2 and a half years and recorded the air temperature, precipitation, and nutrient content in edible vegetation at the sampling site. After conducting 16S rRNA and shotgun metagenomic sequencing, we found that the highest alpha diversity, the relative abundance of Firmicutes, and the simplest co‐occurrence network occurred in winter, whereas the highest relative abundance of Proteobacteria and the most complex network structure were observed in spring. The highest relative abundance of Verrucomicrobiota and Spirochaetota was seen in summer and autumn, respectively. Air temperature, precipitation, and the contents of crude protein, crude fiber, and polysaccharide in vegetation had significant effects on the seasonal changes in gut microbiota. Diet contributed more to microbial variation than climatic factors. Metagenomic analysis revealed that the amino acid metabolism pathway and axillary activity enzymes were most abundant in summer, while abundance of carbohydrate‐binding modules and carbohydrate esterases was highest in spring. These microbial variations were related to the changes in dietary nutrition, indicating that gut microbiota of plateau pika contribute to the efficient use of food resources. This study provides new evidence of how external environmental factors affect the intestinal environment of small mammals.

Patterns in pottery use reveal different adaptive strategies between lower and higher altitude regions on the Tibetan Plateau: Chemical evidence from pottery residues

It has long been recognised that the frigid and hypoxic environment on the high-altitude Tibetan Plateau influences the choices of cooking methods and food compositions. Although commonly used for cooking in the plain areas during the Neolithic Age, the functions of pottery in the high-altitude regions have rarely been examined from archaeological studies. In the present study, lipid residues of pottery fragments from Klu lding (ca. 2900 m a.s.l.) and Khog Gzung (ca. 3900 m a.s.l.) were analysed to present the insight of pottery use and subsistence strategies at different elevations around 3600-3000 BP in the southern Tibetan Plateau. The lipid molecular and isotopic data indicate that vessels were mainly used, though less intensively compared with the plain areas, for the processing of animal fats. At Klu lding, pig adipose fats contribute large proportions of the lipid residues, and leafy plants were used as regular complements to the diets. At Khog Gzung, the broad range of carbon isotopic values points to the wide vertical migrations of the ruminants, implying the hunting of wild ungulates or seasonal transhumance. The first lipid residue analysis performed on high-altitude pottery offers supplementary information about human subsistence strategies for altitudinal adaptations. In the low-altitude regions, the use of local food resources including leafy plants and porcine fats was consistent with the more sedentary lifestyle, providing complements to the early agricultural system. In the high-altitude regions, higher mobility was associated with long-distance hunting or early pastoralism.

Distinct gut microbiomes in two polar bear subpopulations inhabiting different sea ice ecoregions

Gut microbiomes were analyzed by 16S rRNA gene metabarcoding for polar bears (Ursus maritimus) from the southern Beaufort Sea (SB), where sea ice loss has led to increased use of land-based food resources by bears, and from East Greenland (EG), where persistent sea ice has allowed hunting of ice-associated prey nearly year-round. SB polar bears showed a higher number of total (940 vs. 742) and unique (387 vs. 189) amplicon sequence variants and higher inter-individual variation compared to EG polar bears. Gut microbiome composition differed significantly between the two subpopulations and among sex/age classes, likely driven by diet variation and ontogenetic shifts in the gut microbiome. Dietary tracer analysis using fatty acid signatures for SB polar bears showed that diet explained more intrapopulation variation in gut microbiome composition and diversity than other tested variables, i.e., sex/age class, body condition, and capture year. Substantial differences in the SB gut microbiome relative to EG polar bears, and associations between SB gut microbiome and diet, suggest that the shifting foraging habits of SB polar bears tied to sea ice loss may be altering their gut microbiome, with potential consequences for nutrition and physiology.

Coexistence of endemic peacock basses (Cichla) in a Neotropical reservoir (Cichlidae: Cichliformes)

Abstract Peacock basses (genus Cichla) are predatory fish widely distributed across the Amazon, where two or more species normally coexist in a same drainage. The mechanisms that allow coexistence remain poorly understood, although these species share a number of functional traits and behavioral aspects. To advance on this question, the present study compared population and functional traits of Cichla kelberi and C. piquiti, based on data collected between 2010 and 2020 in the upper section of the Lajeado Reservoir, Tocantins River. Both species were captured in all sampling sites, frequently in a same sample, but C. piquiti was far more frequent and abundant. The species used the same habitats, and co-occurred more often than expected by chance. Species had a similar diet (small-sized fish), reproductive effort, fecundity and fat accumulation, but C. piquiti showed larger body sizes, shoaling behavior, a longer reproductive period, and morphology associated with greater swimming potential. Overall, results revealed that these species coexist in the impoundment, with significant overlap in the use of habitats and food resources. Differences in other functional traits may favor their coexistence, possibly involving niche partitioning, which seem to explain the dominance of C. piquiti in the impoundment.

Traditional nutrition as a mechanism for adaptation to the natural and socio-economic environment

The paper deals with the phenomenon of traditional nutrition of Romanians from the Prut-Dniester region as an important mechanism of ethno-ecological adaptation serving as regulation of energy exchange between the human body and the environment. It will also reflect the interdependent relations between nutrition and food products obtained in the households and determined by the natural conditions of living. It should be mentioned that the principal occupations of the population: agriculture, cattle breeding, fishery, beekeeping etc., develop in line with the natural conditions. Therefore, we will elucidate some representative elements for the system of values, ethnic history and culture of our people: specific characteristics of the traditional dietary regime, daily and seasonal food, ritual dishes, technical processes of preparation and consumption, etiquette. The overall evaluation of daily nutritional ration, with the exceptions caused by climatic (drought etc.), economic and social factors, proves that it provides a complete range of essential vitamins and minerals, and the traditional nutritional system is the result of biological, historical and cultural processes fusion. The impact of the ecosystem on food resources and on the formation of metabolism in the local population is also analysed. It identifies some specific features of nutrition of Romanians from the studied area related to the aspect of rational use and processing of food resources, as well as maintaining the balance with the environment.

Strong and weak sustainability in Nordic aquaculture policies

In this paper, we critically analyze how sustainability is considered in aquaculture policies and strategies using the Nordic countries as a case. The strong versus weak sustainability concepts are used to define and clarify what sustainability aspects are central to each state. To illustrate these concepts further, we draw on and modify four mainstream environmental discourses defined by John Dryzek and apply them to the strong and weak sustainability dichotomy to help categorize how environmental sustainability is portrayed in Nordic aquaculture policies and strategies. Subsequently we apply the characteristics of the concepts to aquaculture and sustainability in the Nordic countries. This allows us to identify each state's depiction of sustainable aquaculture, compare these to one another and assess where the Nordic states position themselves regarding sustainability and aquaculture. Our findings show that the policies emphasize technological advancements, intensification, and economic growth, which correlates with weak sustainability. Environmental sustainability receives a significant role in the documents too but does not seem to trump increased intensification or profitability. All policies are heavily focused on fed aquaculture and in order to reduce negative impacts from aquaculture there is a need to incorporate key elements of strong sustainability in policies, including measures to reduce impacts from pollution and the spread of pathogens, use of high-grade food resources and energy consumption. This to transform the industry to sustainability rather than just making it less unsustainable.

Cluster-cooperative project-the basis of rational use of forest food resources in the Amur region

The Amur region has a significant potential for non-wood plant resources: food, medicine, feed, and technology. The northern regions have a territorial advantage in the potential of forest production, where there is a low and average level of agricultural production against the background of a fairly high level of unemployment among the working-age population. Taking into account the cluster policy of the region in the implementation of the designed portfolio of pilot cluster projects, a cluster-cooperative project for the development of an agricultural consumer cooperative for the production, processing and marketing of berries, aimed at the production and production of a wide range of products using wild plants, the formation of a competitive level of price and quality that meets the demand and requirements of customers of export (international) markets, was developed. Through cooperation and integration of personal subsidiary farms within the framework of the project, it is planned to create a single logistics center of the cluster for managing commodity flows of products, ensuring product quality, and organizing certification of products for export. The project is fully integrated into the structure of the organizational and functional mechanism of the agro-industrial cluster of the Amur region, providing support for the project at all stages from the initial stage of project formation to the release of products for export. It is assumed that the implementation of the developed cluster-cooperative project will form the basis for the rational use of non-wood forest resources in the region and will serve not only as a source of income for the local population, the consolidation of permanent personnel in forestry, the development of small and medium-sized businesses, and will also contribute to increasing the productivity of forest plantations.

Ontogenetic niche specialization of the spider crab Libinia ferreirae associated with the medusa Lychnorhiza lucerna.

Symbiotic relationships in marine environments are not fixed and can change throughout the animal's life. This study investigated the ontogeny of symbiosis of the spider crab Libinia ferreirae with the host medusa Lychnorhiza lucerna. We described the type of relationship, the temporal correlation among species, and food habits. More than 50% of the sampled crabs were symbionts, most in early life stages. The highest number of crabs found in a single medusa was 11. Symbiosis was observed throughout most of the year but was more evident in warm periods. The crab has many benefits in this relationship with a medusa. One is the use of food resources captured by the medusa, primarily copepods. Because the crab steals the medusa's food, it is a kleptoparasitic relationship. There is a niche partition between symbiont and the free-living crabs as they occupy different habitats and use nonoverlapping food resources. Previous research reported that symbiosis first developed during the crab's last larval phase (megalopa) when crab and medusa are in the same habitat. Observation of the crab's behavior shows that symbiosis occurs when the crab can grab to the medusa when the host touches the sea bottom. The crab also took advantage of water currents, releasing itself from the substrate and then drifting toward the medusa. The symbiotic relationship that crabs have with the medusa provides then with a nursery, food resources, shelter, dispersion, and decreased competition with free-living adult crabs, all essential for the crab's survival.

Nitrogen losses from food production in the North China Plain: A case study for Quzhou

Nitrogen (N) management is essential for food security. The North China Plain is an important food producing region, but also a hotspot of N losses to the environment. This results in water, soil, and air pollution. In this study, we aim to quantify the relative contribution of different crops and animals to N losses, by taking the Quzhou county as a typical example in the North China Plain. We developed and applied a new version of the NUtrient flows in Food chains, Environment, and Resource use (NUFER) model. Our model is based on updated information for N losses in Quzhou. Our results show that N losses to the environment from crop and animal production in Quzhou were approximately 9 kton in 2017. These high N losses can be explained by the low N use efficiency in food production because of poor N management. For crop production, wheat, maize, and vegetables contributed 80% to N losses. Ammonia emissions and N leaching have dominant shares in these N losses. Pigs and laying hens were responsible for 74% of N losses from animal production. Ammonia emissions to air and direct discharges of manure to water were the main contributors to these N losses. Effective reduction of N losses requires improving the nutrient management in crop (wheat, maize, vegetables) and animal (pigs, laying hens) production. Our work could support the Agricultural Green Development in the North China Plain.

Значение рыбы для населения русского сибирского города Тары в конце XVI — XIX веках

The foundation of the first Russian cities in Western Siberia at the end of the 16 th century was fraught with many difficulties, a key one being a food security system that had to be created in the shortest possible time. Food supplied from the European part of Russia came with long delays and was not enough to provide for the entire population. In the conditions of the impossibility of rapid development of arable land and the formation of its own bread base, the use of local food resources on the basis of hunting and fishing came to the fore. For the city of Tara, the local water bodies — the IrtyshRiver and its tributaries and oxbow lakes — became a source of food. The materials obtained in the course of many years of archaeological research in the historical center of the city have provided data on the species and age composition of the fish caught. Archaeological collections contain ample evidence of the use of various fishing tackles, from collective nets and dragnets to individual fishing rods and spears. All this allowed to get a general idea of the importance of fish for the population of the city during the three centuries of its history, to show the main methods and labor costs of fishing, and the role of fish in the formation of the Siberian market.

‘Taking Fishers’ Knowledge to the Lab’: An Interdisciplinary Approach to Understand Fish Trophic Relationships in the Brazilian Amazon

Trophic levels can be applied to describe the ecological role of organisms in food webs and assess changes in ecosystems. Stable isotopes analysis can assist in the understanding of trophic interactions and use of food resources by aquatic organisms. The local ecological knowledge (LEK) of fishers can be an alternative to advance understanding about fish trophic interactions and to construct aquatic food webs, especially in regions lacking research capacity. The objectives of this study are: to calculate the trophic levels of six fish species important to fishing by combining data from stable isotopes analysis and fishers’ LEK in two clear water rivers (Tapajós and Tocantins) in the Brazilian Amazon; to compare the trophic levels of these fish between the two methods (stable isotopes analysis and LEK) and the two rivers; and to develop diagrams representing the trophic webs of the main fish prey and predators based on fisher’s LEK. The fish species studied were Pescada (Plagioscion squamosissimus), Tucunaré (Cichla pinima), Piranha (Serrasalmus rhombeus), Aracu (Leporinus fasciatus), Charuto (Hemiodus unimaculatus), and Jaraqui (Semaprochilodus spp.). A total of 98 interviews and 63 samples for stable isotopes analysis were carried out in both rivers. The average fish trophic levels did not differ between the stable isotopes analysis and the LEK in the Tapajós, nor in the Tocantins Rivers. The overall trophic level of the studied fish species obtained through the LEK did not differ from data obtained through the stable isotopes analysis in both rivers, except for the Aracu in the Tapajós River. The main food items consumed by the fish according to fishers’ LEK did agree with fish diets as described in the biological literature. Fishers provided useful information on fish predators and feeding habits of endangered species, such as river dolphin and river otter. Collaboration with fishers through LEK studies can be a viable approach to produce reliable data on fish trophic ecology to improve fisheries management and species conservation in tropical freshwater environments and other regions with data limitations.

Isotopic niches of tropical birds reduced by anthropogenic impacts: a 100‐year perspective

The intensification of land‐use changes in tropical forests during the 20th century, mainly caused by deforestation for agricultural uses, had an overwhelming influence on bird assemblages. However, how these historical anthropogenic changes have impacted the habitat use and diet of tropical birds is poorly known. Stable isotope analysis (δ13C and δ15N) can be useful in this regard since it provides information not only on the habitat and food resource use but also insights on the dietary niche of species. Here, we aimed to evaluate whether centenary anthropogenic impacts, mainly caused by changes in landscape composition, have affected the resource and habitat use and isotopic niche width of Neotropical birds in a region that comprises two biodiversity hotspots – the Atlantic Forest and Cerrado in southeastern Brazil. We found that the niche width of all bird guilds (frugivore, granivore, insectivore, nectarivore and omnivore) was largely reduced (28–70%) from the 20th century until recently. This niche width reduction was likely associated with historical anthropogenic impacts (e.g. fragmentation, forest loss and change in agricultural practices), which are responsible for the decrease in the availability of habitat and food resources. Moreover, the mean values of δ15N decreased over the years in all bird guilds, which might be attributed to the expansion of agricultural areas and the increase in the use of synthetic nitrogen‐based fertilizers. All the analyzed species, even though some of them are diet and habitat generalists, were strongly influenced by centenary anthropogenic actions. Our results show the consequences of human‐induced changes in land use on the diet and habitat use of tropical birds that persist in fragmented landscapes, which might compromise their long‐term survival and provide useful information to the conservation strategies of bird assemblages in modern landscapes.

Harnessing Indigenous Technologies for Sustainable Management of Land, Water, and Food Resources Amidst Climate Change

Through advancements in technology humans have cultivated more food, used more fossil fuel reserves, polluted the environment, and caused climate change. This was not the case some few decades ago where indigenous technologies were used in exploiting natural resources. Unfortunately, the effects of climate change on the planet are no more distant reality. The melting of glaciers, rising sea levels, extreme rainfall, and prolonged drought are already being experienced. These have affected water resources, land, and food security across the world. The limits of conventional climate change adaptation and mitigation strategies call for the integration of indigenous knowledge and technologies for tackling climate change issues. This is because of the importance that indigenous knowledge and technologies have for identifying the impacts and as well providing effective adaption and mitigation strategies to climate change. Thus, this chapter explores the potential of indigenous knowledge and technologies for the sustainable management of water, land, and food security amidst climate change. The applications of indigenous technologies and knowledge such as agroforestry, the use of sacred groves to conserve water, land, and biodiversity resources, and the practising of conservation-agriculture are discussed as solutions for reducing greenhouse gas emissions, water shortages, land degradation, and pollution. However, these indigenous technologies will be less useful in today's world if not harnessed. Thus also in this chapter, the scientific know-how available to improve the effectiveness of indigenous technologies for the sustainable use of water, land, and food resources have been identified (Robotics, sensors/detectors, internet of things) and discussed.

Differential use of trophic resources between an exotic and a coexisting native snail

Knowing the interactions between exotic and native species is essential to establish possible threats to the local fauna. In this study, we assessed the use of food resources and diet overlap between a recently introduced snail, Sinotaia quadrata, and a native species, Pomacea canaliculata. We analyzed the gut content and stable isotope of snails and resources in a lowland stream where both species coexist. Both Schoener’s and isotope dietary overlap indexes supported dietary overlap. Conversely, gut content analysis showed differences in consumption: S. quadrata consumed more detritus and diatoms than P. canaliculata, whose diet was characterized by detritus and macrophyte remains. Macrophytes were the resource that most contributed to the diet of both species, as shown by stable isotope mixing models. The combination of both techniques, gut content and stable isotope analysis, indicated that S. quadrata consumed macrophyte detritus while P. canaliculata ate fresh macrophytes. This difference indicates differential use of food resources between the studied species coexisting in a lowland stream. Although no negative trophic interaction was found, we highlight the importance of continuing to monitor interactions for other resources and studying possible risks to the local fauna.

Predator abundance drives the association between exploratory personality and foraging habitat risk in a wild marine meso‐predator

Abstract In recent years, the incorporation of lower levels of organization to the understanding of population ecology, has led to an increase in interest for animal personality and individual foraging specialization. Despite these topics investigating comparable phenomena, that is, individual consistency in behaviour and in food resource use respectively, they have rarely been investigated together. Food resource use is thought to be at the interface between personality and life history. More explorative individuals in a population, for example, are thought to increase encounter rates with food resources and consequently have faster growth than less explorative conspecifics. Such hypotheses have so far only received partial support, and the link between personality and life history is increasingly speculated to be plastic and dependent on spatio‐temporal variation in ecological conditions. Intraspecific competition and/or predation risk, for example are known to influence foraging specialization. Here, we investigated the relationship between exploration personality of juvenile lemon sharks Negaprion brevirostris (measured in captivity) and foraging habitat use (high risk vs. low risk; measured via stable isotope analysis in the field) in relation to conspecific and predator abundance. We identified predator abundance as the main driver for the association between foraging habitat and exploration personality. When predators were less abundant, increased exploration was associated with foraging in riskier habitats. When predator abundance increased, an inverse relationship occurred, with less explorative individuals using more dangerous habitat. We conclude that the relationship between personality and resource use is plastic and context dependent, which could explain the inconclusive results of previous studies investigating links between personality and life history. A free Plain Language Summary can be found within the Supporting Information of this article.

Rapid response of the giant protist xenophyophores (Foraminifera, Rhizaria) to organic matter supply at abyssal depths revealed by an in situ dual stable isotope labeling experiment

The trophic ecology of xenophyophores (Foraminifera, Rhizaria) was examined during a 2-day in situ feeding experiment on the seafloor (water depths of 5370 m) off the east coast of Torishima Island, Japan. Both 13C-labeled glucose (as an example of labile dissolved organic matter) and 15N-labeled diatoms (as an example of labile particulate organic matter sinking from the ocean surface) were supplied to the specimens captured in in-situ incubation cores using the manned submersible Shinkai 6500. We found that xenophyophores took up both dissolved and particulate organic matter during the 2 days of incubation in situ. The higher concentrations of 15N-labeled diatoms in the xenophyophores than in the surrounding sediments suggest efficient collection and use of food resources by xenophyophores, and may support their rapid growth. It is likely that the agglutinated test of xenophyophores, which forms a contorted plate-like structure with upper open fan-like and funnel-like elements, also contributes to their ability to collect phytodetritus derived from the ocean surface.

The behavior of Gammarus aequicauda (crustacea, amphipoda) during predation on chironomid larvae: Sex differences and changes in precopulatory mate‐guarding state

The foraging behavior determines the diet size influencing the growth and reproduction of a predator and its prey populations. Amphipods play a key role in various aquatic ecosystems. Gammarus aequicauda is an abundant widespread omnivorous species and the only known amphipod species of hypersaline waters. Its predation can suppress the populations of planktonic and benthic invertebrates. Males of G. aequicauda actively eat chironomid larvae but there is no data on predatory females. Experiments were conducted to study sex-related differences in feeding behavior including during precopulatory mate guarding (PCMG). There were significant sex differences in feeding characteristics. For females, calculations showed that maximum consumption could be 3-4 chironomid larvae per day and for males about 9-10 larvae per day. During PCMG, males did not feed and females fed as efficiently as single females. Males transported females and alone carrying the energetic costs of swimming during PCMG. Less expenditure of energy on swimming means more energy for reproduction for females. This allows more energy-efficient use of food resources and increases the reproductive success of the population. There are currently two alternative views on PCMG among crustaceans. 1. It is a sexual conflict between males and females serving as a male adaptive strategy to achieve a female during strong male competition, while females bear many costs during the long guarding period. 2. There is also the opposite view that pairs get energetic benefits from long PCMG. Obtained data suggest that PCMG is likely to be intersexual cooperation and not intersexual conflict.

Interspecific competition affects resource use by three cryptic freshwater species ofHyalellaSmith, 1874 (Amphipoda: Hyalellidae)

AbstractSpecies that use the same resources present a paradox for understanding their coexistence. This is especially true for cryptic species because they are phenotypically similar. We examined how competition affects food-resource use in three cryptic species of Hyalella Smith, 1874, a freshwater-amphipod genus. We hypothesized that competitively inferior species would use high-quality algae patches when alone and competitively superior species would displace inferior species to low-quality patches. We compared use of foraging patches varying in algal content (i.e., quality) when species were alone or with another species. Our results showed that the competitively inferior species spent more time on the low-quality patch in the presence of the competitively superior species, but the behavior of the competitively superior species was independent of heterospecifics. This study provides insight into the role of interspecific competition in shaping resource use and patterns of coexistence in nature.