Food Webs最新文献

{"title":"Ecological gatekeeping: Black-backed jackals are left to crave carrion in absence of large facultative scavengers","authors":"Haemish Melville,&nbsp;Maxine Gaines,&nbsp;Kerry Slater,&nbsp;W. Maartin Strauss","doi":"10.1016/j.fooweb.2023.e00310","DOIUrl":"https://doi.org/10.1016/j.fooweb.2023.e00310","url":null,"abstract":"<div><p>Carrion removal is a key ecological function of scavengers, and they promptly dispose of carcasses in those large African conservation areas where predator assemblages remain intact. Despite its species richness, the grassland biome is critically threatened in southern Africa, and the predator assemblage is no longer intact in most of the biome. We used camera traps to monitor scavenger activity at five blue wildebeest (<em>Connochaetes taurinus</em>) carcasses on the Telperion Nature Reserve, characterized by rocky highveld grassland. We found that, in absence of larger vertebrate scavengers, black-backed jackals (<em>Canis mesomelas</em>) were unable to access fresh blue wildebeest carcasses, gaining access only once invertebrate action opened the skin. We also observed black-backed jackals eating flies accumulating on grass near to carcasses. These observations show that the avenues of resource provisioning by carcasses are not limited to direct carrion consumption. Moreover, they raise questions about potentially important cascading effects of not having intact predator assemblages, in smaller conservation areas.</p></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"37 ","pages":"Article e00310"},"PeriodicalIF":1.7,"publicationDate":"2023-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49863471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectral radius is a better metric than weighted NODF to detect network nestedness: Linking species coexistence to network structure using a plant – larval sawfly bipartite","authors":"Bin Lan ,&nbsp;Xingyu Zhou ,&nbsp;Nan Yang ,&nbsp;Shucun Sun","doi":"10.1016/j.fooweb.2023.e00303","DOIUrl":"10.1016/j.fooweb.2023.e00303","url":null,"abstract":"<div><p></p><ul><li><span>1.</span><span><p>Network nestedness<span> describes an interaction pattern, wherein specialist species interact with a subset of partner species. Antagonistic networks are predicted to not be nested, because nestedness indicates a high intensity of interspecific competition, which compromises species coexistence. However, network nestedness is commonly observed in antagonistic networks, and the discrepancy between prediction and observation has not been fully resolved.</span></p></span></li><li><span>2.</span><span><p>One of underlying factors explaining this discrepancy is the imperfection of metrics to detect network nestedness. However, studies comparing network metrics often fail to resolve which metric works best, presumably because they lack specific criteria.</p></span></li><li><span>3.</span><span><p>We compared the results of the most commonly used metrics (weighted NODF) and a later proposed metric (spectral radius) to measure the nestedness of a quantitative plant - larval sawfly bipartite (including 8 sawfly species and 66 plant species, identified by gut DNA metabacoding of larvae). We also determined whether the sawfly species can coexist in terms of their dietary differences. Because nested structure is not likely to be compatible with species coexistence, we assumed that the metric identifying a non-nested structure is superior to the other.</p></span></li><li><span>4.</span><span><p>The two metrics led to contrasting nestedness levels. Both observational and preference networks were found to be nested using weighted NODF, but was not nested using the spectral radius approach.</p></span></li><li><span>5.</span><span><p>The dietary differences were significant among each sawfly species pair for both observational and preference networks, indicating low interspecific competitiveness and a high potential for species coexistence.</p></span></li><li><span>6.</span><span><p>These results indicate that the spectral radius metric is superior to weighted NODF to detecting network nestedness and should be used in future network studies.</p></span></li></ul></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"36 ","pages":"Article e00303"},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48036834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineral licks as a potential nidus for parasite transmission","authors":"William J. Severud ,&nbsp;Todd M. Kautz ,&nbsp;Jerrold L. Belant ,&nbsp;Seth A. Moore","doi":"10.1016/j.fooweb.2023.e00299","DOIUrl":"10.1016/j.fooweb.2023.e00299","url":null,"abstract":"<div><p>Discrete landscape features can concentrate animals in time and space, leading to non-random interspecific encounters. These encounters have implications for predator-prey interactions, habitat selection, intraspecific competition, and transmission of parasites and other pathogens. The lifecycle of the parasitic nematode <em>Parelaphostrongylus tenuis</em> requires an intermediate host of a terrestrial gastropod. Natural hosts of <em>P. tenuis</em> are white-tailed deer, and an aberrant host of conservation concern is moose, which are susceptible to high levels of mortality as a naive host to the parasite. Intermediate hosts become infected when <em>P. tenuis</em> larvae are shed in deer feces, then consumed or enter the gastropod through the foot. Incidental (or perhaps intentional) ingestion of infected gastropod intermediate hosts by aberrant or dead-end hosts often results in mortality of that animal. We present photographic evidence depicting a potential mechanism for transmission from infected white-tailed deer to moose, heretofore not examined in the literature. We deployed remote cameras at mineral licks around Grand Portage Indian Reservation in northeastern Minnesota, USA. We observed white-tailed deer defecating at mineral lick sites and geophagous moose at the same sites. We hypothesize that mineral licks may act as a nidus for <em>P. tenuis</em> transmission between deer and moose in this system and call for further research into the potential role of mineral licks in parasite transmission.</p><p>The Grand Portage Band of Lake Superior Chippewa is a federally recognized Indian tribe in extreme northeastern Minnesota, USA, and proudly exercises its rights to food sovereignty through subsistence hunting and fishing. Mooz (Moose) are a primary subsistence food used by the Anishinaabeg (people) of Grand Portage Band historically and presently. Management for and research on maintaining this moose population as a vital subsistence species thus sets the context for this paper examining potential for disease transmission between white-tailed deer and moose through shared use of mineral licks.</p></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"36 ","pages":"Article e00299"},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48445556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Specialist shorebird respond to prey and habitat availability through trophic plasticity","authors":"Lais Gliesch ,&nbsp;Bruno de Andrade Linhares ,&nbsp;Carla Penna Ozorio ,&nbsp;Paulo Henrique Ott ,&nbsp;Júlia Jacoby ,&nbsp;Leandro Bugoni ,&nbsp;Guilherme Tavares Nunes","doi":"10.1016/j.fooweb.2023.e00300","DOIUrl":"10.1016/j.fooweb.2023.e00300","url":null,"abstract":"<div><p><span>Spatiotemporal variations in food availability represent a challenge to the persistence of specialist species. The American oystercatcher (</span><em>Haematopus palliatus</em><span>) is a shorebird regarded as a bivalve specialist, although foraging habitats and prey species may vary along its distribution. Here, we studied American oystercatcher breeding in sites with variable landscapes to test the effect of temporal and spatial variations in food availability and dietary aspects. Between 2017 and 2021, we sampled oystercatchers (</span><em>n</em><span> = 100) and macroinvertebrates at the mesolitoral zone in five foraging areas in southern Brazil, three composed by sand and rock substrates (mixed), and two by sandy beach only. We obtained biological samples from oystercatchers and macroinvertebrates for carbon (</span><em>δ</em>¹³C) and nitrogen (<em>δ</em>¹⁵N) stable isotope analysis. In addition, we carried out systematic sampling of macroinvertebrates in sandy beaches at foraging areas to assess prey availability. Main findings showed the oystercatcher diet to be influenced both by the heterogeneity of foraging habitats and temporal fluctuations in availability of food resources. Bivalves contributed ∼60% to the diet of oystercatchers, but differences in the preferred bivalve species were detected among areas. In sites with mixed substrates, oystercatchers had a wider isotopic niche, suggesting habitat heterogeneity induced a more varied diet. Finally, we also observed interannual variation in the diet that may be associated with variation in macroinvertebrate availability on sandy beaches, especially for non-bivalve prey. Therefore, both temporal variations in food availability and foraging habitat heterogeneity seem to shape the foraging ecology of oystercatchers in the coastal zone, evidencing trophic plasticity in this specialist shorebird.</p></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"36 ","pages":"Article e00300"},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43813405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Video observations of wolves hunting ungulates on linear features","authors":"Thomas D. Gable ,&nbsp;Sean M. Johnson-Bice ,&nbsp;Austin T. Homkes ,&nbsp;Joseph K. Bump","doi":"10.1016/j.fooweb.2023.e00297","DOIUrl":"10.1016/j.fooweb.2023.e00297","url":null,"abstract":"<div><p>Anthropogenic linear features allow wolves to travel faster and more efficiently, which is thought to increase wolf hunting efficiency of ungulates. Most previous studies have evaluated the role of linear features in wolf-ungulate dynamics by relying on indirect observations (e.g., GPS location data). Thus, there remains little direct observational data showing how wolves use linear features to hunt ungulates. Here, we present observational data (29 hunting sequences) of wolves using linear features to hunt ungulates. Linear features have largely been considered travel corridors that facilitate wolf movement and allow wolves to detect prey <em>near</em> (but not necessarily <em>on</em>) linear features. However, we clearly demonstrate wolves also use linear features as active hunting arenas where they detect, pursue, and kill prey that are also traveling <em>directly on</em><span> linear features. Our observations further suggest one of, if not the, primary way wolves detect ungulates on linear features is via olfactory cues.</span></p></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"36 ","pages":"Article e00297"},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44270593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trophic chain of the pelagic thresher, Alopias pelagicus, in the Southeastern Pacific Ocean: An approach through stable isotopes of carbon and nitrogen","authors":"Marcos D. Calle-Morán ,&nbsp;Peggy J. Loor-Andrade ,&nbsp;Felipe Galván-Magaña","doi":"10.1016/j.fooweb.2023.e00294","DOIUrl":"10.1016/j.fooweb.2023.e00294","url":null,"abstract":"<div><p>The pelagic thresher, <span><em>Alopias</em><em> pelagicus</em></span><span>, plays a vital role in coastal and marine ecosystems<span> as a top predator that feeds on species from low trophic levels. It is a commercial species relevant in Ecuador. The feeding chain of </span></span><em>A. pelagicus</em><span> was analyzed through carbon and nitrogen stable isotopes in the Southeast Pacific Ocean. Considering the lack of studies regarding this topic, this would elucidate the flow of nutrients and energy from the base up to this predator. Its diet composition included 19 prey species, out of which 10 were cephalopods and nine Osteichthyes<span>. The most relevant species were the squid </span></span><span><em>Ommastrephes bartramii, </em><em>Dosidicus gigas</em><em>, Stenoteuthis oualaniensis</em></span>, and the fish <em>Merluccius gayi peruanus</em>. The pelagic thresher is a carnivore predator, and its prey species belong to tertiary and quaternary trophic levels. The carbon and nitrogen male isotopic ratios were similar to those of females, as were immature and mature organisms. This suggests that this species feeds in oceanic regions of low depths and could be exploiting and sharing an area with similar feeding resources. According to the mixing models, squids were the most important prey group, in which the squid <em>Ommastrephes bartramii</em> contributed most to its diet. Furthermore, this shark was characterized as a specialist predator with a trophic overlap by sex and maturity stages.</p></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"36 ","pages":"Article e00294"},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42405709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fight or flight: Eastern wild Turkey repeatedly defends nest against raccoon","authors":"Wesley W. Boone ,&nbsp;Reese Johnson","doi":"10.1016/j.fooweb.2023.e00289","DOIUrl":"10.1016/j.fooweb.2023.e00289","url":null,"abstract":"<div><p>Eastern wild turkeys (<span><em>Meleagris gallopavo</em><em> silvestris</em></span>) are an economically and culturally important species throughout eastern and central North America. Eastern wild turkey nests are predated by a suite of predators, providing sustenance for those predators but also potentially adding to recent turkey population declines. While studies of wild turkey nest success and nest predation rates are common, many rely on artificial nests which fail to account for the defensive capabilities of nesting hens. Direct observation of attempted and successful predation events are largely absent from the literature, but needed to understand these interspecific interactions. Following the chance discovery of an eastern wild turkey nest we placed two camera traps overlooking the nest. The camera traps recorded six attempted nest raids by a raccoon (<span><em>Procyon lotor</em></span>), of which only once did the raccoon appear to steal an egg. The remaining five attempts were fended off by the hen, which puffed her feathers and defended the nest. We conclude that hens may be capable of defending their nests against attempted predation events by raccoons, but additional research is needed to determine if this hen's defensive capacity is typical and whether other predators are more successful at raiding nests.</p></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"36 ","pages":"Article e00289"},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41496174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predation of oak acorns by Baird's tapir in one of the last remnants of mountain cloud forest in Southern Mexico","authors":"Josué Israel Puc-Sánchez ,&nbsp;Angela A. Camargo-Sanabria ,&nbsp;Eduardo Mendoza","doi":"10.1016/j.fooweb.2023.e00312","DOIUrl":"10.1016/j.fooweb.2023.e00312","url":null,"abstract":"<div><p><span>The consumption of fruits and seeds by mammals can have a strong impact on the regeneration of tropical forests. Our knowledge of this biotic interaction has steadily increased recently but it remains fragmentary. This is largely due to most of the studies focusing on a small proportion of the diverse mammals and plants involved in these interactions and to the fact most commonly used methods provide just partial information about the whole seed dispersal/predation process. The use of camera traps has opened the opportunity to greatly improve our knowledge of the intricacies of frugivory and seed predation by increasing the likelihood to record very secretive animal species and providing detailed accounts of their behavior. Based on camera trap data we report acorn consumption of </span><span><em>Quercus</em><em> benthamii</em></span> and <em>Q. sapotifolia</em> by the threatened Baird's tapir (<span><em>Tapirus</em><em> bairdii</em></span>). This study was conducted in the largest remnant of Mountain cloud forest in Mexico, located in El Triunfo Biosphere Reserve (ETBR) in the state of Chiapas. Despite the fact that ten mammal species were recorded in the focal trees, only two of them (<em>T. bairdii</em> and <em>Sciurus deppei</em>) were documented exhibiting acorn consumption. We obtained 82 videos showing the consumption of <em>Q. benthamii</em> acorns by tapirs (sampling effort = 133 camera trap days, <em>n</em> = 8 trees) with an average of 6.04 ± 3.56 (± sd) minutes spent on this activity. In comparison, we only obtained one video of a tapir consuming <em>Q. sapotifolia</em> acorns (sampling effort = 264 camera trap days, <em>n</em> = 5 trees) during 35 s. Consumption of these <em>Quercus</em> species by tapir was not previously reported. Moreover, our study is the first (to our knowledge) to show video-recorded evidence of the interaction between tapirs and <em>Quercus</em> trees. Due to tapirs' large body size, the consumption of acorns might be an important source of mortality for some <em>Quercus</em> species (e.g., <em>Q. benthamii</em>).</p></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"37 ","pages":"Article e00312"},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45579702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The trophic ecology of an invasive predator in a novel ecosystem: Green sunfish Lepomis cyanellus in a restored urban stream","authors":"Brittany A. Babbington ,&nbsp;Augustin C. Engman ,&nbsp;Z. Winston Clark ,&nbsp;Alonso Ramírez","doi":"10.1016/j.fooweb.2023.e00292","DOIUrl":"10.1016/j.fooweb.2023.e00292","url":null,"abstract":"<div><p><span>Rapid urbanization will increase the number of novel stream ecosystems in the Southeastern United States. The green sunfish (</span><span><em>Lepomis cyanellus</em></span><span><span><span>) is a globally widespread, invasive species<span> that is particularly well-adapted to urban stream conditions. The trophic ecology of green sunfish is understudied, especially in the novel ecosystems where they appear to thrive. We assessed predation by green sunfish in the food web of a heavily engineered and restored urban stream in Raleigh, North Carolina. We sampled fish species composition, size structure, abundance, the benthic macroinvertebrate assemblage, and fish diets during two seasons. Green sunfish was the sole species inhabiting the study stream, with the exception of a single </span></span>goldfish. The population size structure indicated potential overcrowding in our study ecosystem. </span>Chironomidae was the most common taxa in both the benthic macroinvertebrate assemblage and in fish diets during the summer. We observed a seasonal shift in diets to lesser prey-specific abundance of Chironomidae and a greater overall abundance of terrestrial prey from summer to winter. Green sunfish can persist in small restored urban streams of the Southeast US where virtually no other fish occur, and they utilize benthic invertebrates and terrestrial prey as resources.</span></p></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"36 ","pages":"Article e00292"},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41291451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Olingos do eat insects: Records of nocturnal mammals preying on arthropods in arboreal live-capture traps","authors":"Diego Balbuena ,&nbsp;Giancarlo Inga ,&nbsp;Lourdes Ponce ,&nbsp;Roselvira Zuniga ,&nbsp;Roland Kays","doi":"10.1016/j.fooweb.2023.e00298","DOIUrl":"10.1016/j.fooweb.2023.e00298","url":null,"abstract":"<div><p><span>The natural history of arboreal tropical mammals is poorly known, especially nocturnal species, because they are difficult to find. Most observations in the wild come from congregations at fruiting trees, but the extent to which they eat items other than fruit is not known. Here we report the first recorded insectivore behavior of eastern lowland olingos (</span><em>Bassaricyon alleni</em><span>) in the wild, confirming that insects are part of their diet. We also report Orthoptera<span> and Lepidoptera as part of the diet of brown-eared wooly opossums (</span></span><em>Caluromys lanatus</em>) and mouse opossums (<em>Marmosa</em><span> sp.). We used camera traps to record the behavior of animals attracted to different baits as part of a program of pre-baiting arboreal live-capture traps in Amazonian Peru. We recorded 4 predatory events of olingos, 11 of wooly opossums, and 3 of mouse opossums catching and eating Orthoptera, Lepidoptera, and possibly other arthropods. These observations confirm that olingos eat insects, as well as fruits, and add information to the known omnivore<span> diet of arboreal opossums and possible niche differences with sympatric species like the kinkajou (</span></span><em>Potos flavus</em>). We suggest more detailed diet studies through collection of feces or isotopic analysis should be used to determine the relative importance of these food items, and thus the ecological roles they play in neotropical forests.</p></div>","PeriodicalId":38084,"journal":{"name":"Food Webs","volume":"36 ","pages":"Article e00298"},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46081053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}