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The article presents a commentary to the paper "Old Growth (OG) and Secondary Forest (SF) Site Occupancy by Nocturnal Birds in a Neotropical Landscape," by M. Sberze, M. Cohn-Haft and G. Ferraz. According to the author, the perceived conservation value of SF is due to the fact that most old growth forests will be lost and the rapid increase in SF area throughout the tropics. The study investigated the occurrence of three pairs of nocturnal bird species within OG and SF sites near Manuas, Brazil and examined assumptions about habitat preference.

Shipwrecks have been accidentally and deliberately deployed worldwide, becoming artificial reefs for tourist attractions and habitats for marine species. Recreational divers often visit wrecks and post images on Instagram – a popular social network for image circulation. Here we evaluated if such images could be used as a data source for surveying sea turtles in shipwrecks and assessing diver–sea turtle interactions. We targeted the coast of Pernambuco in Brazil, which has over 100 shipwrecks. We inspected public videos and photos posted on Instagram from October 2010 to April 2020. We used 20 tags in our search, which led to 2353 images (210 videos; 2143 photos). A total of 220 posts depicted sea turtles (189 photos and 31 videos; 41 sea turtles in videos and 199 in photos) and their enhanced quality‐facilitated species identification. We detected Caretta caretta (loggerhead sea turtle), Chelonia mydas (green sea turtle) and Eretmochelys imbricata (hawksbill sea turtle). Turtles were found in 13 shipwrecks, all with bathymetry up to 30 m. Photos and videos provided the same proportion of images of each turtle species. Nevertheless, from a temporal perspective, this scenario changed. All three species were observed in photo posts in 4 of the 9 full years considered, whereas all three species were only observed in 1 year in the video posts. We registered four types of diver–turtle interactions from videos: 'abrupt approach, chase, touch and pose'. We classified 'abrupt approach, chasing and touching' behaviours as major disturbances as they altered the turtles' behaviours. We classified 'pose' as a minor disturbance as it caused no apparent change in turtle behaviour. Chasing was the most frequently observed interaction. Instagram is a useful complementary tool that can aid in the surveillance of sea turtles in shipwrecks. However, the limitations of this type of data and adequate data filtering criteria must be considered. [ABSTRACT FROM AUTHOR]

How species persist in fragmented habitats is essential to understanding species resilience in response to increasing anthropogenic pressures. It has been suggested that expansion in dietary niche allows populations to persist in human‐modified landscapes, yet this hypothesis has been poorly tested in highly diverse ecosystems such as tropical forests where frugivory is ubiquitous. Here, we measured dietary niche expansion of a large forest‐dwelling mammal, the white‐lipped peccary (Tayassu pecari), in the Atlantic Forest, Brazil, by comparing its diet using stable carbon (δ13C) and nitrogen (δ15N) isotopes. We collected hair of white‐lipped peccaries in three continuous and three fragmented forests and compared δ13C and δ15N values, resource use and isotopic niches among populations and between forest types. We also tested the relationship between isotopic values of the populations and the forest cover percentage. White‐lipped peccaries fed mainly on forest sources (C3 resources), especially in continuous forests, but 28% of the individuals in fragmented sites also incorporated C4 resources to some extent. In fragmented forests, the populations had isotopic niches from 3‐ to 3.6‐fold the size of those in continuous forests. This niche expansion was due to the consumption of food items with higher δ15N values and C4 crops. Differences among populations were larger among fragmented forests, suggesting variable site‐specific strategies to cope with habitat loss. The mean isotopic values of white‐lipped peccary populations were negatively correlated with the loss of forest cover. Some small forest fragments might still retain relatively high habitat quality, and white‐lipped peccaries might be able to capitalize on such variety of resources, shifting their diets from those observed in continuous forests. We suggest that high dietary flexibility and dietary expansion toward consumption of non‐forest resources might facilitate the persistence of large frugivores in fragmented habitats. [ABSTRACT FROM AUTHOR]

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Retaliatory killing, motivated by depredation of domestic animals by large carnivores, has had a significant impact on wild predators' populations. In Brazil, pumas and jaguars are the most persecuted species, so it is important to analyse the spatial patterns of depredation risk of livestock. We aimed to identify the hotspots of depredation risk by these two felids in Brazil, as well as the most important variables that determine the risk at the biome scale. We generated spatial models of livestock depredation using a database of depredation records, anthropogenic, topographic and vegetation variables, and ecological niche models. We used six algorithms to generate spatial risk models of depredation and selected those with the best performance, for inclusion in a consensus model, for each biome. Finally, we overlapped the areas of high depredation risk by both felids, so that areas considered as hotspots are those in which there is a high risk that livestock will be preyed by pumas or jaguars. Approximately 17% of the area of the biomes analysed for puma had high depredation risk, and 18% in the case of jaguar. The hotspots encompassed 6.5% of the included biomes' area. The variables associated with the high depredation risk were different between species and biomes. Depredation risk by pumas was primarily associated with anthropogenic variables, whereas a combination of anthropogenic variables and vegetation types increased depredation risk by jaguar. Biome‐scale analysis, coupled with the availability of reliable data and the implementation of statistically robust methods, provides information specifically on the areas of highest risk and the conditions that contribute to it. [ABSTRACT FROM AUTHOR]

Large‐scale climatic processes such as the El Niño‐Southern Oscillation (ENSO) can have severe effects on the survival of seabirds in their breeding regions. However, there is a fundamental lack of understanding about how environmental factors are related to the mortality of these organisms in non‐breeding areas of the tropics. We investigate here the direct and indirect effects of ENSO and oceanographic variables on the mortality of three migratory seabird species targeted by conservation programmes focused on human impacts: the Atlantic yellow‐nosed albatross Thalassarche chlororhynchos, the Magellanic penguin Spheniscus magellanicus and the Manx shearwater Puffinus puffinus in a non‐breeding area in Brazil, tropical Atlantic. We find that the intensification of ENSO increases the mortality of Manx shearwaters by enhancing the local storm activity. The mortality of Atlantic yellow‐nosed albatrosses and Magellanic penguins is also related to a local increase in storm activity but regardless of the ENSO signature. Increased mortality of Magellanic penguins is observed when biological productivity falls below the annual average (1.7 mg m−3). Adverse climatic conditions are highly deleterious for migratory seabirds and single storm episodes can cause massive deaths, thus exacerbating population declines. We argue that conservation and management strategies for migratory seabirds studied here should not only focus on direct human impacts but should also consider mitigating the effects of climate variability. [ABSTRACT FROM AUTHOR]

Post-release monitoring data of reintroduced captive-bred birds can be utilized to help optimize future avian reintroduction programs. We present a case study of broad interest to reintroduction and conservation biologists interested in investigating movements and habitat use by reintroduced captive-bred birds. We used radio telemetry to monitor reintroduced captive-bred red-billed curassow Crax blumenbachii at a private reserve, Rio de Janeiro state, Brazil. During August 2006 and October 2008, 25 radio-tagged individuals (15 females and 10 males, all <30 months old) were monitored over a 25-month period. Evaluation of home-range size and habitat use revealed that captive-bred curassows should be released only into forest areas with adequate riverine habitat that are larger than the minimum home-range movements of the proposed population. Curassows also utilized pastureland, cultivated areas and secondary forests, suggesting that the proximity of release sites to such habitats may not be entirely detrimental for future reintroductions. Site fidelity for reintroduced birds was low, and there was a tendency for resident curassows to move away when new cohorts were released into the area. Determining how habitat characteristics, displacement by newly released cohorts, adjustments to their new surroundings or cohort social interactions influence post-release movements of resident birds at release sites over prolonged time frames would improve our knowledge on the impacts of releasing further captive-bred individuals into habitats with extant populations. Critically, the movement patterns of reintroduced curassows identified in this study demonstrate that avian post-release monitoring must be considered over an appropriate time frame and we highlight how different conclusions may be generated depending on the duration of post-release monitoring. It may take more than 2 years for reintroduced captive-bred sub-adults to become established following release and that post-release monitoring of similar duration may not be adequate for large avian species such as Cracids. [ABSTRACT FROM AUTHOR]

The golden-headed lion tamarin Leontopithecus chrysomelas occurs in the Atlantic forest of southern Bahia, Brazil, where shade-cocoa agroforestry (known as cabruca) predominates. The economic decline of the cocoa industry has caused many landowners to convert cabruca into cattle pasture or diversify their plantations with other crops. These and prior anthropogenic disturbances such as habitat fragmentation are threatening lion tamarin persistence. For some lion tamarin groups, cabruca comprises a large part of their home range. Considering these factors, the maintenance of the biological diversity in cabruca favorable to golden-headed lion tamarins is of considerable interest to their long-term survival. Here we identify plant species that provide food and sleeping sites for the lion tamarins and examine their occurrence in cabruca plantations, in order to investigate alternatives for conservation management practices that benefit both lion tamarins and cabruca. We determined the total number of trees and the frequency of individuals and species used for food and sleeping sites by lion tamarins in Una Biological Reserve, Bahia, from 1998 to 2006. We used this information to compare the richness and frequency of use across habitats ( cabruca, mature and secondary) and to create a ranking index considering various components of a tree species' utility to the lion tamarins. Lion tamarins used 155 tree species, 93 for food and 93 for sleeping sites. Fifty-five species were ranked as ‘Extremely Valuable,’ eight as ‘Valuable’ and 92 as ‘Of Interest.’ Of 48 families, Myrtaceae and Sapotaceae were used the most. Cabruca contained fewer individual trees used by lion tamarins, but the highest frequency of use per tree compared with other habitats, indicating the large influence of single trees in these plantations. Using the key tree species identified in our study in the management of cabruca would be of considerable benefit to the long-term survival of lion tamarins [ABSTRACT FROM AUTHOR]

High rates of old growth (OG) forest destruction and difficult farming conditions result in increasing cover of secondary forests (SF) in the Amazon. In this setting, it is opportune to ask which animals use newly available SF and which stay restricted to OG. This study presents a comparison of SF and OG site occupancy by nocturnal birds in terra firme forests of the Amazon Guianan shield, north of Manaus, Brazil. We tested species-specific occupancy predictions for two owls ( Lophostrix cristata/Glaucidium hardyi), two potoos ( Nyctibius leucopterus/Nyctibius griseus) and two nightjars ( Caprimulgus nigrescens/Nyctidromus albicollis). For each pair, we predicted that one species would have higher occupancy in OG while the other would either be indifferent to forest type or favor SF sites. Data were collected in 30 OG and 24 SF sites with monthly samples from December 2007 to December 2008. Our analytic approach accounts for the possibility of detection failure and for spatial autocorrelation in occupancy, thus leading to strong inferences about changes in occupancy between forest types and between species. Nocturnal bird richness and community composition were indistinguishable between OG and SF sites. Owls were relatively indifferent to forest type. Potoos followed the a priori predictions, and one of the nightjars ( C. nigrescens) favored SF instead of OG as predicted. Only one species, Nyctib. leucopterus, clearly favored OG. The landscape context of our SF study sites, surrounded by a vast expanse of continuous OG forest, partially explains the resemblance between SF and OG fauna but leaves unexplained the higher occupancy for SF than OG sites for several study species. The causal explanation of high SF occupancy remains an open question, but the result itself motivates further comparisons for other groups, as well as recognition of the conservation potential of SF. [ABSTRACT FROM AUTHOR]

Edge effects are a well-known result of habitat fragmentation. However, little has been published on fragmentation, isolation and the intrusive influence from the surrounding matrix at the landscape level. The objectives of the present study are to evaluate the presence of dogs in the Brasília National Park (BNP) in relation to habitat type and the influence from the surrounding matrix. In addition, this study examines the response of the native mammal fauna to the presence of dogs. Track stations were built along dirt roads in the BNP and subsequently examined for the presence or absence of tracks. We used a stepwise logistic regression to model the occurrence of five mammal species relative to habitat variables, with an α=0.05 to determine whether to enter and retain a variable in the model. A simulation of each species occurrence probability was conducted using a combination of selected habitat variables in a resource selection probability function. Results indicate a negative relationship between distance from the BNP edge and the probability of dog occurrences. From an ecological perspective, the presence of dogs inside the BNP indicates an edge effect. The occurrence of the maned wolf was positively associated with distance from a garbage dump site and negatively associated with the presence of dog tracks. The maned wolf and giant anteater seem to avoid areas near the garbage dump as well as areas with dog tracks. There is no support for the possible existence of a feral dog population inside the BNP, but the effects of free-ranging dogs on the wildlife population in such an isolated protected area must not be neglected. Domestic dog Canis familiaris populations and disease control programs should be established in the urban, sub-urban and rural areas surrounding the BNP, along with the complete removal of the garbage dump from the BNP surroundings. [ABSTRACT FROM AUTHOR]

The fact that species vary in their vulnerability to extinction is well documented, but the reasons for these differences remain poorly understood. Why should some species/families/guilds decline rapidly with increasing anthropogenic disturbance, while others either tolerate or proliferate in disturbed habitats? We investigated the bird species composition in 31 primary forest patches of varying size in a region of the Amazonian ‘Arc of Deforestation’ and assessed which species life-history traits predisposed individual species to extinction. Medium-sized non-flocking canopy frugivores/ominvores of low primary forest dependence were least likely to go extinct in small patches, while small-bodied flock-following primary-forest-dependent terrestrial insectivores were most fragmentation sensitive. We found highly idiosyncratic relationships between the minimum size of forest patches occupied by different species and their territory size requirements estimated based on other Amazonian studies. This suggests that avian assemblages in forest fragments primarily comprise species that either have good dispersal abilities or are highly tolerant to the non-forest matrix, rather than those whose minimum spatial requirements can be met by the size of available forest fragments. [ABSTRACT FROM AUTHOR]