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Eastern wild turkeys (Meleagris gallopavo silvestris) 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 (Procyon lotor), 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.

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 Quercus benthamii and Q. sapotifolia by the threatened Baird's tapir (Tapirus bairdii). 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 (T. bairdii and Sciurus deppei) were documented exhibiting acorn consumption. We obtained 82 videos showing the consumption of Q. benthamii acorns by tapirs (sampling effort = 133 camera trap days, n = 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 Q. sapotifolia acorns (sampling effort = 264 camera trap days, n = 5 trees) during 35 s. Consumption of these Quercus 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 Quercus trees. Due to tapirs' large body size, the consumption of acorns might be an important source of mortality for some Quercus species (e.g., Q. benthamii).

Rapid urbanization will increase the number of novel stream ecosystems in the Southeastern United States. The green sunfish (Lepomis cyanellus) is a globally widespread, invasive species 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 goldfish. The population size structure indicated potential overcrowding in our study ecosystem. 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.

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 (Bassaricyon alleni) in the wild, confirming that insects are part of their diet. We also report Orthoptera and Lepidoptera as part of the diet of brown-eared wooly opossums (Caluromys lanatus) and mouse opossums (Marmosa 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 diet of arboreal opossums and possible niche differences with sympatric species like the kinkajou (Potos flavus). 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.

The diet of an organism is related to its intrinsic characteristics, such as morphology, physiology, and behavior, and those of the prey it consumes. For species occurring in sympatry, the knowledge of the mechanisms that favor the co-occurrence of morphologically and ecologically similar species may be important to understand the resource partition in the assemblage. In this study, we analyze the diet of small to large hylids (i.e., Scinax fuscomarginatus, Dendropsophus anataliasiasi, Boana caiapo, and B. raniceps) in an Amazonia-Cerrado transitional zone, verifying if the diet of species with different body sizes is similar and if species diet is explained by the availability of prey in the environment. We found that the dietary patterns of the studied hylids were not driven by prey availability in the environment, with species feeding preys in an opportunistic way. In addition, the diet composition was similar among species, however, the volume of consumed prey varied according to the body size, with large species feeding more prey volume than the small ones. This pattern is predicted by the optimal foraging theory, in which larger predators tend to maximize their energy intake by consuming large prey. Altogether, the segregation depending on the body size can play a key role in trophic resource partitioning, with small species feeding small prey and larger species consuming small to large prey, but preferring the larger ones when there is an option, avoiding interspecific competition.

Understanding complete ecological roles of species requires insight into various predator-prey relationships. Bald eagles (Haliaeetus leucocephalus) have been documented to consume a variety of species, including turtles. The ground beneath eight bald eagle nests located in Alabama and Tennessee were searched during the 2016, 2017, and 2018 nesting seasons for discarded turtle remains. Six turtle genera were documented, but the most abundant turtle genera observed were Graptemys and Sternotherus. Most remains were juveniles or adult males; however, the Sternotherus remains could have been adult males or females. The distance of the eagle nest to the nearest major waterway appeared to influence whether Graptemys or Sternotherus was the major turtle prey observed. The presence of different contaminants in these turtle species should be examined to determine if they potentially contribute to biomagnification in bald eagles.

Two-toed sloths (genus Choloepus) are almost exclusively arboreal. However, they often descend to the ground in places known as mineral licks or “saladeros” and feed from soil, which presumably enhances their digestion of toxins and helps them obtain minerals not readily available in their diet. Mineral licks are risky areas which may increase their visitors' vulnerability to predators. Here, we report a predation attempt on an adult Linnaeus two-toed sloth (Choloepus didactylus) by an adult ocelot (Leopardus pardalis) at a mineral lick at the Tiputini Biodiversity Station in the Ecuadorian Amazon. Predation events are rarely recorded in camera traps, and this particular predation event can be considered unusual, given that sloths usually come down to mineral licks during the night. Also, it is not clear how ocelots are able to capture sloths, and other arboreal animals and this record evidence that predation of arboreal vertebrates by ocelots may also take place in the ground. Finally, the anti-predatory behavior displayed by the two-toed sloth demonstrates that there are intrinsic risks for predators while attempting to capture prey.

The consumption of carrion is a key process in food web ecology and a common foraging strategy for facultative scavengers in the carnivore guild. As carrion represents a high-quality trophic resource, carcasses may be visited by multiple carnivore species and have the potential to act as hotspots for intraguild interactions. Mesocarnivores frequently consume carrion, yet the mechanisms used by these species to access carcasses and coexist with larger carnivores have been poorly studied. Here, we investigate the factors influencing carcass use by two understudied African mesocarnivores, the side-striped jackal (Canis adustus) and the African civet (Civettictis civetta). Using camera traps to monitor ungulate carcasses in Liwonde National Park (LNP), Malawi, we assess the influence of competing carnivores (spotted hyena; Crocuta crocuta), carcass size and carcass age on mesocarnivore detection rates. Jackals frequently consumed carrion and their detection at a carcass was positively associated with civet presence, increasing the potential for competitive interactions. Co-occurrence of jackals and civets, where both species were detected simultaneously, were mainly recorded at large (>200 kg) carcasses, suggesting competitive interactions were reduced when more abundant resources were available. Jackal and civet detection at a carcass was not influenced by the presence of spotted hyena, although we found evidence that civets use temporal partitioning to access carcasses at times of reduced spotted hyena activity. Continued monitoring of carcasses will be important to further understand carnivore coexistence dynamics, particularly as large carnivore populations recover in LNP.

Stream ecosystems are reliant on the reciprocal exchange of terrestrial and aquatic energy subsides to maintain a productive and stable food web. Land use around streams can have strong effects on the size and availability of resource subsidies for stream and riparian predators such as fish and spiders. A common forestry technique around streams is the establishment of forested buffers to protect aquatic and riparian ecosystems from upland disturbances. Buffer size may determine prey abundance, richness, and spatial extent of prey reach into both the aquatic and terrestrial systems. To test the effects of forested buffers subsidy direction, we explored the carbon and nitrogen stable isotope signatures of brown trout (Salmo trutta), Tetragnathidae and Lycosidae spiders, and their aquatic and terrestrial prey sources around twelve streams in southern Sweden. For both predator groups, buffer presence showed no effect on resource subsidy source. We found that both brown trout and spiders are significantly reliant on terrestrial sources of prey for their diets in the fall. To support the terrestrial subsidy into small streams it is vital to maintain ecologically functional riparian zones by conserving complex surrounding habitats that optimize habitat and both terrestrial and aquatic prey diversity.

Understanding species (co)-occurrence patterns and how these are affected and mediated by humans is essential for the development of management plans to guide coexistence between humans and wildlife. Here, we evaluated two opposing hypotheses regarding the effects of humans on species occurrence: “humans as super-predators” and “humans as shield”, using an existing camera-trap dataset of mammal species occurrence collected in the coffee forests of southwestern of Ethiopia. We applied a multispecies occupancy modelling framework to explicitly examine co-occurrence patterns between humans, top-predators, prey, and crop-raiders, along a gradient of forest integrity (characterized by forest cover and fragmentation). We examined co-occurrence patterns during both coffee and non-coffee harvest seasons. Our results show partial support for the “humans as shield” hypothesis. We found (i) signs of co-occurrence between humans and prey in areas of low forest integrity during both survey seasons, and between humans and raiders during the coffee-season, (ii) signs of co-occurrence between prey and raiders during both seasons, (iii) no signs of negative or positive co-occurrence between humans and top-predators. Our findings indicate that a possible “shield effect” between humans and prey within a predator space, might be undergoing at the edges of coffee forests. Our findings suggest that incorporating humans as one more species in the ecological system can contribute to shed light into the effects of humans on species occurrence and ultimately contribute to inform management for coexistence.