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SummaryTourism can be a powerful tool for wildlife conservation if well controlled and responsibly managed. Apex predators constitute particularly attractive subjects for tourism, but simultaneously they may generate conflict with local communities. Harpy Eagles Harpia harpyja are the largest eagle species and are highly sought-after by ecotourists. The last stronghold of the Harpy Eagle is the Amazon Forest, which is being deforested for cattle ranching. We tested methods for developing Harpy Eagle ecotourism as a potential tool to harmonize these issues. Using camera traps, we collected data on timing of Harpy Eagle visits to their nests, as well as on probabilities of viewing an eagle. Harpy Eagles can only be seen predictably during the first 12 of the 30–36 month nest cycle. In nests with nestlings (up to 5–7 months), adults are visible on a daily basis, and this period lasts 16.6% of the nesting cycle, demanding a minimum of 13, 17, and 26 nests to have at least one nest with a nestling on 90%, 95% and 99% of the days. After this 5–7 month window, we found that two and 4.16 days spent at nests afforded high probabilities of sighting a fledgling or adult eagle, respectively. Harpy Eagles were mainly active at the beginning and the end of the day. Activity core lasted 6.5 decimal hours for adults, peaking at 10h00, and 7.45 decimal hours for fledged eagles, peaking at 15h00. Our results demonstrate that Harpy Eagles fit several criteria for a viable wildlife attraction: predictable in activity and location, viewable, and diurnal, even though at the same time they are considered a rarity. In a broader perspective, Harpy Eagle tourism shows every indication of being a significant tool for more robust rainforest conservation.

Background Climate plays a key role in the life histories of tropical vertebrates. However, tropical forests are only weakly seasonal compared with temperate and boreal regions. For species with limited ability to control core body temperature, even mild climatic variation can determine major behavioural outcomes, such as foraging and predator avoidance. In tropical forests, sloths are the arboreal vertebrate attaining the greatest biomass density, but their capacity to regulate body temperature is limited, relying on behavioural adaptations to thermoregulate. Sloths are largely or strictly nocturnal, and depend on crypsis to avoid predation. The harpy eagle (Harpia harpyja) is a sloth-specialist and exerts strong top-down control over its prey species. Yet the role of environmental variables on the regulation of predator–prey interactions between sloths and harpy eagles are unknown. The harpy eagle is considered Near Threatened. This motivated a comprehensive effort to reintroduce this species into parts of Mesoamerica. This effort incidentally enabled us to understand the prey profile of harpy eagles over multiple seasons. Methods Our study was conducted between 2003 and 2009 at Soberanía National Park, Panamá. Telemetered harpy eagles were seen hunting and feeding on individual prey species. For each predation event, field assistants systematically recorded the species killed. We analysed the effects of climatic conditions and vegetation phenology on the prey species profile of harpy eagles using generalised linear mixed models. Results Here we show that sloth predation by harpy eagles was negatively affected by nocturnal ambient light (i.e. bright moonshine) and positively affected by seasonally cool temperatures. We suggest that the first ensured low detectability conditions for sloths foraging at night and the second posed a thermally unsuitable climate that forced sloths to forage under riskier daylight. We showed that even moderate seasonal variation in temperature can influence the relationship between a keystone tropical forest predator and a dominant prey item. Therefore, predator–prey ecology in the tropics can be modulated by subtle changes in environmental conditions. The seasonal effects shown here suggest important demographic consequences for sloths, which are under top-down regulation from harpy eagle predation, perhaps limiting their geographic distribution at higher latitudes.

Domestic dogs (Canis lupus familiaris) are one of the most common exotic species in protected areas, and their impact is an important conservation concern. This study evaluated the occurrence of domestic dogs in one of the world's largest urban forests, the Tijuca National Park (TNP; 3953 ha), the most visited Park in Brazil. From April to September 2016, 42 camera-trap stations, spaced 0.5 km among them, were set in TNP, covering an area of 1050 ha. Population size and density of dogs were estimated, and the spatial distribution of dogs evaluated in relation to the distance to the Park's boundaries and to paved roads. Dogs’ circadian activity pattern and its overlap with those of the five most recorded native mammal species were also studied. The estimated population size of dogs was 29 ± 4.86 (mean ± SE) individuals, and the estimated density was between 0.74 ind./km2 and 1.37 ind./km2. Domestic dogs were widely distributed in the Park, and the number of independent dog records was not related to proximity to paved roads or the boundaries of the Park. The domestic dog was mainly diurnal in TNP, overlapping its activity mostly with the red humped agouti Dasyprocta leporina and the coati Nasua nasua. The absence of pups indicates that dogs come from surrounding areas rather than being a feral population within TNP. Therefore, managing strategies must consider the engagement of local people.

The loss or reduction of animal populations and consequent extinction of ecological interactions in Neotropical forests demand urgent conservation initiatives to reverse these trends. One of the rainforests with the highest levels of mammal defaunation is the Brazilian Atlantic Forest. Local mammalian extinctions in the biome were evaluated to set out priorities. Researchers, reserve managers and ex situ animal keepers throughout the Atlantic Forest were connected through a reintroduction network. From 2010 to 2017, we reintroduced two important seed dispersers, the red-humped agouti and the brown howler monkey, in Tijuca National Park, Rio de Janeiro, with other species on their way. We monitored the reintroduced populations regarding demography, spatial patterns, diet and their effect on ecological interactions. They interacted with several plant species, including large-seeded ones. We found 25 dung beetles’ species interacting with howlers’ feces. As TNP lacked medium and large sized frugivores, the increased dispersal can have a disproportional effect on forest regeneration. Among the main constraints for refaunation programs we pointed out delays to obtain environmental licenses, scarcity of source populations and difficulties regarding quarantine, release and monitoring of the animals. Refaunation has shown promise as a low-cost, effective way to restore ecological processes in defaunated Neotropical forests. Fil: Fernandez, Fernando A.S.. Universidade Federal do Rio de Janeiro; Brasil Fil: Rheingantz, Marcelo L.. Universidade Federal do Rio de Janeiro; Brasil Fil: Genes, Luísa. Universidade Federal do Rio de Janeiro; Brasil Fil: Kenup, Caio F.. Universidade Federal do Rio de Janeiro; Brasil Fil: Galliez, Maron. Universidade Federal do Rio de Janeiro; Brasil Fil: Cezimbra, Tomaz. Universidade Federal do Rio de Janeiro; Brasil Fil: Cid, Bruno. Universidade Federal do Rio de Janeiro; Brasil Fil: Macedo, Leandro. Universidade Federal do Rio de Janeiro; Brasil Fil: Araujo, Bernardo B.A.. Universidade Federal do Rio de Janeiro; Brasil Fil: Moraes, Bruno S.. Universidade Federal do Rio de Janeiro; Brasil Fil: Monjeau, Jorge Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Fundación Bariloche; Argentina. Universidade Federal do Rio de Janeiro; Brasil Fil: Pires, Alexandra S.. Universidade Federal do Rio de Janeiro; Brasil

Reintroduction of locally extirpated species is an increasingly popular conservation tool. However, few initiatives focus on the restoration of ecological processes. In addition, many reintroductions fail to conduct post-release monitoring, hampering both assessment of their success and implementation of adaptive management actions. In 2009 a reintroduction effort was initiated to re-establish a population of the red-rumped agouti Dasyprocta leporina, a scatter-hoarding rodent known to be an important disperser of large seeds, with the aim of restoring ecological processes at Tijuca National Park, south-east Brazil. To assess whether this reintroduced population established successfully we monitored it using mark–resighting during November 2013–March 2015. Population size and survival were estimated using a robust design Poisson-log normal mixed-effects mark–resight model. By March 2015 the number of wild-born individuals fluctuated around 30 and overall growth of the population was positive. As the reintroduced population is capable of unassisted growth, we conclude that the reintroduction has been successful in the medium term. We recommend the cessation of releases, with efforts redirected to continued monitoring, investigation and management of possible threats to the species’ persistence, and to quantification of the re-establishment of ecological processes. Reintroduction of D. leporina populations can be a cost-effective tool to restore ecological processes, especially seed dispersal, in Neotropical forests.

Territory size is affected by distribution of resources, density of potential competitors, body size of the territory holder and its ability to detect intruders. During four consecutive years (2009–2013), we determined territory size of the serra antwren, a highly territorial bird, that occupies permanent territories in the restinga habitat. We studied seasonal variation and relationship between territory size, number of neighboring territories and floaters (mature individuals without fixed territories), and body size of the territory holders. We also estimated population density using a capture–recapture method. Territory size was smaller during the breeding season with its size affected by number of neighboring territory holders and year. Densities were estimated to be 1.6–5.8 indiv. ha–1, which were 2 to 6 times higher than the value previously estimated by fixed-radius point counts (0.93 indiv. ha–1). This may be due to the high number of floaters, potentially important but usually neglected in density estimates. Neighboring territory holders affected more than floaters territory size, possibly because of their similar individual qualities.