There is increasing interest in the restoration/regeneration of degraded tropical habitats yet the potential role of natural regenerators remains unclear. We test the hypothesis that the richness and functional diversity of terrestrial mammals differs between forest regrowth stages. We quantified the richness and functional diversity of eight terrestrial mammal seed-disperser species across a forest regrowth gradient in the eastern Brazilian Amazon. We installed camera-traps in 15 sites within small-holder properties with forest regrowth stage classified into three groups, with five sites each of: late second-regrowth forest, early second-regrowth forest and abandoned pasture. Species richness and functional dispersion from the regrowth sites were compared with 15 paired forest control sites. Multi model selection showed that regrowth class was more important for explaining patterns in richness and functional diversity than other variables from three non-mutually exclusive hypotheses: hunting (distance to house, distance to river, distance to town, small holder residence), land cover (% forest cover within 50 meters, 1 kilometer and 5 kilometers) and land use (regrowth class, time since last use). Differences in functional diversity were most strongly explained by a loss of body mass. We found that diversity in regrowth sites could be similar to control sites even in some early-second regrowth areas. This finding suggests that when surrounded by large intact forest areas the richness and functional diversity close to human small-holdings can return to pre-degradation values. Yet we also found a significant reduction in richness and functional diversity in more intensely degraded pasture sites. This reduction in richness and functional diversity may limit the potential for regeneration and increase costs for ecological regeneration and restoration actions around more intense regrowth areas.

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Highlights The occurrence, density and biomass of adult arborescent palms were measured in a National Forest in the eastern Brazilian Amazon. Commercially important arborescent palms were rare. Density and biomass were related to hydrographic and topographic variables. Subsidised agroforestry practices are required to facilitate the commercialization of palm NTFPs. Published as:Norris, D., Chuma, V.J.U.R., Arevalo-Sandi, A.R., Paredes, O.S.L. and Peres, C.A., 2016. Too rare for non-timber resource harvest? Meso-scale composition and distribution of arborescent palms in an Amazonian sustainable-use forest. Forest Ecology and Management, 377,. oleracea, an economically important species. The presence, biomass, and density of palms were uncorrelated with geographic distances among plots. The hydrographic model significantly explained variation in palm presence and biomass, whereas density was only explained by the topographic model. Our findings indicate that arborescent palms are currently too rare to be efficiently harvested as NTFPs in the study area. Yet, comparisons with published estimates suggest that there is significant potential for agroforestry to facilitate the commercialization of palm NTFPs for community based extractive activities.

Trichechus inunguis is an endemic species of the Amazon, which inhabits mainly in lakes and calm rivers. The objective of this study case was to describe the social behaviour of two female-orphaned calves, of T. inunguis in captivity. They were kept in the same pool at the facilities of the Amazon Rescue Center (ARC, Iquitos, Peruvian Amazon). Between February and October 2011, the individuals were observed during day and night times, completing 352 hours of observation. Through ad libitum observation of the individuals, we developed a catalogue of social behaviors that includes descriptions of 93 behaviours, classified in eight behavioural categories.. The frequency of behaviours was assessed by instantaneous sampling (for states) and continuous recording (for events). Manatees displayed mainly social behaviours, and the most frequent interaction was the simultaneous starting of the same behaviour by both individuals. Most of social behaviours occurred during the day, but 'group resting' was recorded mostly at night. 'synchronized breathing' and 'group feeding' did not have temporary variation between days or between daytimes. Regarding the use of the space, the majority of interactions occurred in shaded places. This study revealed strong interactions between confined calves, suggesting that social activity may play an important role in their learning process.Keywords: endangered species, ethology, social behaviour, Trichechus inunguis. RESUMENTrichechus inunguis es una especie endémica del Amazonas que vive principalmente en lagos y ríos de aguas tranquilas. El objetivo de este estudio de caso fue describir el comportamiento social de dos crías hembras huérfanas de T. inunguis en cautiverio, mantenidas en el mismo estanque en el Centro de Rescate Amazónico (CREA, Iquitos, Amazonía peruana). Entre febrero y octubre de 2011, las crías fueron observadas durante el día y la noche, para un total de 352 horas de observación. Desarrollamos un catálogo de comportamientos social para los individuos mediante observación ad libitum. La frecuencia de comportamientos fue evaluada por muestreo instantáneo (para estados) y registro continúo (para eventos). Los manatíes exhibieron principalmente comportamientos sociales, y la interacción más frecuente fue el inicio simultáneo del mismo comportamiento por ambos individuos. La mayoría de los comportamientos sociales ocurrieron durante el día, pero 'descanso grupal' fue registrado mayormente en la noche. 'respiración sincronizada' y 'alimentación grupal' no tuvieron variación diaria entre días o entre horas del día. En lo que respecta al uso de espacio, la mayoría de interacciones ocurrió en lugares sombreados. Este estudio reveló fuertes interacciones entre crías en cautiverio, sugiriendo que la actividad social cumple un rol importante en los procesos de aprendizaje de los manatíes.Palabras clave: comportamiento social, especie amenazada, etología, Trichechus inunguis.

Mammal groups have a vast variety of habitats, which include aquatic, aerial, arboreal, and terrestrial. For terrestrial habitats, camera traps are used as a common technique to record mammals and other vertebrates and have been recently utilized to observe arboreal animals as well. Here, we compare the difference in mammal diversity between floor and canopy strata and evaluate the use of camera trapping in a lowland forest in central Amazon. We installed nine paired camera traps, one in the canopy stratum and other in the floor stratum, in the Alto Cuieiras Biological Reserve (Brazilian Amazon). With a sampling effort of 720 camera-days, we recorded 30 mammal species: nine in canopy strata, 14 in floor strata, and seven in scansorial strata (sharing both strata). On the forest floor, the species with the greatest abundance was Myoprocta acouchy; in the canopy, Isothrix paguros had the greatest abundance; and among the scansorial species, Proechymis sp. was the most abundant. Our results show the differences in mammal diversity between floor and canopy strata; canopy strata contained more small and frugivorous mammals. Although we obtained a relatively low sampling effort with the camera-trap method compared with other studies utilizing different techniques, our results were especially similar to those of previous studies that worked with canopy and floor strata. Thus, camera trap can be very effective for recording short periods of time, and this method is less physically exhaustive and expensive for researchers to study vertical strata.

Several forest types compose the apparently homogenous forest landscape of the lowland Amazon. The seasonally flooded forests (igapós) of the narrow floodplains of the blackwater rivers of the Amazon basin support their community of animals; however, these animals are required to adapt to survive in this environment. Furthermore, several taxa are an important source of seasonal resources for the animals in the adjacent unflooded forest (terra firme). During the low-water phase, the igapó becomes available to terrestrial species that make use of terra firme and igapó forests. Nonetheless, these lateral movements of terrestrial mammals between hydrologically distinct forest types remain poorly understood. This study tested the hypothesis that the attributes of the assemblages (abundance, richness, evenness, and functional groups) of the terrestrial mammals in both these forest types of the Cuieiras River basin, which is located in the Central Amazon, are distinct and arise from the ecological heterogeneity induced by seasonal floods. After a sampling effort of 10,743 camera trap days over four campaigns, two for the terra firme (6,013 trap days) and two for the igapó forests (4,730 trap days), a total of 31 mammal species (five were considered eventual) were recorded in both forest types. The species richness was similar in the igapó and terra firme forests, and the species abundance and biomass were greater in the terra firme forest, which were probably due to its higher primary productivity; whereas the evenness was increased in the igapós when compared to the terra firme forest. Although both forest types shared 84% of the species, generally a marked difference was observed in the composition of the terrestrial mammal species. These differences were associated with abundances of some specific functional groups, i.e., frugivores/granivores. Within-group variation was explained by balanced variation in abundance and turnover, which the individuals of a given species at one site were substituted by an equivalent number of individuals of a different species at another site. However, the occupancy was similar between both forest types for some groups such as carnivores. These findings indicate that seasonal flooding is a relevant factor in structuring the composition of terrestrial mammal assemblages between terra firme and floodplain forests, even in nutrient-poor habitats such as igapós. The results also highlight the importance of maintaining the mosaic of natural habitats on the scale of the entire landscape, with major drainage basins representing management units that provide sufficiently large areas to support a range of ecological processes (e.g., nutrient transport, lateral movements and the persistence of apex predators).

With continued forest loss in tropical regions, it is important to understand whether and how public policies influence deforestation rates. One potentially important policy is Brazil’s “Native Vegetation Protection Law” (NVPL), passed in 2012 and popularly known as the New Forest Code. The goal of the law is to prevent forest loss; however, its success at maintaining forest is unclear. We analyze the effectiveness of the law in the state of Amazonas, Brazil by measuring forest loss in 2009 and 2012, pre implementation of the new vegetation protection law (NVPL) and comparing this to loss that occurred in 2015 and 2018, post-NVPL, in Settlement Projects (SP) affected by NVPL and Indigenous Lands (IL) and State/National Forests which were not under the mandate of the NVPL. We used these last two categories as Control Areas. Forest loss was greatest in SP during both time periods relative to two other categories considered. Implementation of the NVPL did not reduce overall deforestation in SPs. However, it did keep deforestation within the 20% limit set by NVPL in 31 of 35 SPs surveyed. In addition, forest cover decreased in only a few SPs. The variable with the strongest influence on deforestation within SP and IL was intensity of human land use in surrounding areas. We also found that IL and CU categories play an important role in maintaining overall forest cover.