Semideciduous Atlantic Forest Research Articles

Lestrimelitta chacoana Roig-Alsina, 2010 (Meliponini, Apidae) in a Semideciduous Atlantic Forest, Southern Brazil

The species of the cleptobiotic bee genus Lestrimelitta Friese, 1903 (Hymenoptera: Apidae) are generally known as a menace to Meliponiculture and Apiculture, that is why it is common to observe recommendations to beekeepers to avoid the proximity of their meliponaries with any Lestrimelitta hives. So, besides other anthropic pressures, the growth of beekeeping may represent a particular threat to its species. In this note we address the distribution of three species recorded in the triple border region of Argentina, Paraguay, and Brazil. One of these species, Lestrimelitta chacoana Roig-Alsina, 2010 (Hymenoptera: Apidae), previously described from the Argentinian Dry Chaco, is recorded for the Semideciduous Atlantic Forest in Southern Brazil where it was already expected to be found due to its previous record in a contiguous forest type in Northeastern Argentina. A discussion about the characters to differentiate it from two other species is made.

Pitfall trap efficiency in sampling small vertebrates (Anura, Squamata, and Mammalia) in fragments of the Southeastern Atlantic Forest, Brazil

Pitfall traps are a sampling method broadly used in studies with small terrestrial vertebrates. In this paper, we compared the efficiency of modified pitfall traps in sampling anurans, squamates, and mammals. In two forest fragments of the Seasonal Semi-deciduous Atlantic Forest, we set up 26 arrays of drift fences and pitfall traps, composed of four 30-liter buckets, each set up arranged in a ‘Y’ shape linked by a fence of 4 m in length and 0.5 m in height. We tested for the effect of an internal rim on the border of the buckets by comparing buckets with and without a rim on capture efficiency. In general, we did not observe any effect of the rims in capture efficiency, independently of the bucket position where the rim was present. Still, terminal buckets with rims were less efficient in capturing rodents. We hypothesized that the use of buckets with rims did not increase the capture of small vertebrates due to the animal’s ability to perceive the rim due to substrate instability. However, the pitfall trap efficiently captures small vertebrates, and we do not recommend using the internal rims.

Small forest fragments and their importance for conservation of tree communities in Atlantic Semideciduous Forest

Small forest fragments and their importance for conservation of tree communities in Atlantic Semideciduous Forest

Genetic Diversity of Paryphthimoides poltys (Nymphalidae: Satyrinae: Euptychiina) in a Fragmented Agricultural Landscape in the Brazilian Atlantic Forest

The species-level response of organisms to habitat loss and fragmentation relies on their dispersal ability, as well as trophic level, degree of habitat specialization and landscape structure. For butterflies, community composition is affected by the landscape configuration, by the surrounding habitat and by the matrix composition scattered around forest fragments, whereas higher dispersal ability is a significant advantage for persistence in highly fragmented landscapes. However, species of butterflies are highly variable in their dispersion capabilities, which affects their genetic variability as a whole and in how it is distributed within and between subpopulations in remaining fragments. In the present study, the genetic variability in subpopulations of Paryphthimoides poltys distributed through forest fragments was evaluated. Low diversity and the absence of genetic structure was found through eight fragments of semideciduous Atlantic Forest, surrounded by agricultural matrices, in Southeastern Brazil. Although P. poltys was the most common species found in the area in a previous study, its high abundance was not accompanied by high genetic variability. The species is usually found flying in forest edges and open environments and, although low, its genetic variability is expected to be preserved even if some of the investigated forest fragments are lost in the near future.

Mixed Sampling Methods Reveal Elevated Bat Richness in a Semideciduous Atlantic Forest Remnant

Richness is a key variable for understanding biodiversity, and estimates of species occurrence should be as comprehensive as possible and based on reliable records. The employment of diversified methods to be able to detect species, and of adequate sampling efforts is crucial for estimating the richness of bats occurring in highly complex tropical forests. We herein analyzed the richness of bats from one of the largest remnants of the semideciduous Atlantic Forest from Southeastern Brazil, the state conservation park called Parque Estadual do Rio Doce (PERD), based on data from the 1990s and from 2012 to 2016. Based on mixed sampling techniques, including ground-level and canopy nets, acoustic surveys, and roost searching we have revealed that this single state reserve of PERD has the highest bat richness recorded to date among semideciduous Atlantic Forest locations. A total of 54 bat species have been recorded for PERD, including two recently described species from the genera Thyroptera (Thyropteridae) and Eumops (Molossidae). Our data reinforce the value of diversifying sampling methods and the role of PERD as key area for the conservation of the Atlantic Forest biome.

Interactions of structural and functional characteristics of trees and bamboo in an Atlantic semideciduous forest in Southeast Brazil

Interactions of structural and functional characteristics of trees and bamboo in an Atlantic semideciduous forest in Southeast Brazil

The defense repertoire of males of Leptodactylus vastus Lutz 1930 in a fragment of the Atlantic Forest in northeastern Brazil

Anurans present different defence mechanisms against predator attacks. There are more than 30 defence strategies that these animals can display in the different environments where they can be preyed upon. We analysed the defence repertoire of the species Leptodactylus vastus Lutz 1930, including the male distress call and its intra and interindividual coefficients of variation. We carried out this study in a fragment of Semideciduous Atlantic Forest at the Camocim Conservation Unit in the metropolitan region of Recife, Pernambuco, northeastern Brazil. The defensive displays of 30 males to different stimuli simulating a predator were analysed. We observed five types of strategies which were used by these animals separately or concomitantly: puffing up the body (100%), push movement (83.3%), distress call (33.3%), hiding (23.3%), cloacal discharge (16.6%) and spine aggression (6.6%). The analysis of intra and interindividual coefficient of variation showed that there was no acoustic variation in the distress call of this species. Understanding the defensive mechanisms of a species is important to identify the antipredatory strategies used by animals, especially in face of emerging threats, and to help to produce proposals for the conservation of neotropical species.

Modeling canopy interception under drought conditions: The relevance of evaporation and extra sources of energy

Modeling canopy interception is fundamental for understanding the forests’ role in local and regional hydrology. In this study, canopy interception (CI), throughfall (TF), and stemflow (SF) were evaluated for a semi-deciduous Atlantic Forest (AFR) from 2013 to 2019, where a prolonged dry period occurred. The Gash and Liu models were analyzed in detail to determine the most appropriate for modeling CI throughout drought conditions. Thus, the climatic parameters were retrieved annually by a modified TF-based method (EI%), whereas the structural parameters represented the entire period. The contribution of the energy stored in the forest (i.e. air and biomass; Q) to CI was also assessed in the AFR stand. Both models performed well when using EI%, as the Gash model overestimated CI by 71 mm (4.6%), whereas the Liu model underestimated it by only 13 mm (0.85%). This performance is due to an increased Q and turbulent mechanisms (such as advection and strong updrafts) that occur in drought conditions and are indirectly accounted for in EI%. However, the Liu model stood out for modeling CI under a prolonged dry period, as the exponential wetting approach better represents the complex canopies of the semi-deciduous forests. Thus, we recommend the Liu model and additional energy sources when dealing with prolonged droughts, as in the case of climate change scenarios projected to the studied region.

Disturbance as a driver of trait assembly in liana communities in a semi-deciduous Atlantic Forest

Disturbance as a driver of trait assembly in liana communities in a semi-deciduous Atlantic Forest

Water balance of an Atlantic forest remnant under a prolonged drought period

ABSTRACT Since prolonged droughts have impacted Atlantic forests in Southeastern Brazil, further investigations to understand the effects of such stressful conditions in their hydrological behavior are required. This study aimed to assess the changes in the water balance of a semi-deciduous Atlantic forest remnant and how the forest responds to droughts. The Standardized Precipitation-Evapotranspiration Index was applied to identify droughts (from 1961 to 2019) and their severity in both the hydrological year and summer scales. Drought impacts on actual evapotranspiration, potential percolation, and soil water storage were assessed using Hydrus-1D, having net precipitation and potential evapotranspiration as inputs. Error analyses (< 10%) confirmed Hydrus-1D suitability for simulating soil moisture. Uncertainties regarding the soil saturated hydraulic conductivity are due to preferential flows, which are not accounted for in Richards’ equation. Drought intensification changed forest hydrology and triggered physiological responses to deal with it. Semi-deciduous Atlantic forests are adapted to dry conditions because of the existence of dry-affiliated species and the activation of physiological mechanisms. However, such adaptations responded differently regarding the drought scales. The intensification of summer droughts increased evapotranspiration and decreased the potential percolation. Leaf shedding changed the canopy structure in a two-year time lag as a response to the intensification of hydrological year droughts. Changes in forest hydrology are sudden and trigger physiological responses, such as leaf shedding, in a delayed process after droughts take place.

Optimal plot size for carbon-diversity sampling in tropical vegetation

Obtaining high-quality information on vegetation attributes directly linked to ecosystem services in tropical forests, such as carbon stock and biodiversity, is essential to develop ecological information to be used in planning conservation strategies. Defining the optimum vegetation sample plots size is an important part of the process of obtaining information, since is crucial for its quality, and also for its financial costs and time required. In this context, we evaluated whether: (i) the optimum plot size selected in two approaches (basal area/carbon stock vs biodiversity) are different since they are associated with different ecological drivers; (ii) different tropical forests vegetation types present different optimum sample plot size due to their ecological specific attributes, such as species composition, structure and functioning. For this we evaluated the vegetation sample plots optimum size of different vegetation types of tropical savanna and forest of broad occurrence in the tropics (Atlantic Semideciduous Forest – ASF; Cerrado Woodland – CW; Cerrado Forest – CF; and Seasonally Dry Tropical Forest - SDTF), in two approaches: forest basal area and carbon stock, since they are related variables; and biodiversity variables by species composition similarity and heterogeneity in communities. We used 4 forest fragments in Brazil that were sampled in a way that allowed the arrange of subplots to form different plot sizes. In order to evaluate the optimum sample plot size in the basal area/carbon stock approach we used four methodologies, in which the obtained variability was compared to a reference size (1000 m2). For the biodiversity approach we used the floristic similarity and composition heterogeneity between units as metric, evaluating differences in the similarity patterns and possible reductions or increases in variability compared to the reference size. We found there are no significant differences for biodiversity variables between sample plot sizes for all vegetation types, thus the optimum size may be selected using just the basal area/carbon stock approach. In the basal area/carbon stock approach, most of the evaluated methods generally presented lower plot size values compared to the reference size (1000 m2) in all vegetation types, except for the ASF. There are differences between vegetation types that may be grouped in two groups related to the optimum size selected, that are related to their ecological restriction patterns: CW, CF and SDTF with optimum size between 600 and 1000 m2; and the second with ASF, with optimum sample plot size between 1000 m2 and 1400 m2.

Carbon stock densities of semi-deciduous Atlantic forest and pine plantations in Argentina

Recent studies have shown the importance of subtropical forests as terrestrial carbon sinks and also their vulnerability to human disturbances and climate change. The Semi-deciduous Atlantic Forest presents large extensions replaced by productive uses, such as tree plantations, and forest remnants showing high levels of structural heterogeneity. No studies have performed carbon stock densities estimations in different pools in the region. We wonder how changes in forest structure and forest replacement by pine plantations affect ecosystem carbon stock densities in different pools and fluxes. We performed carbon estimates based on field data and compared closed (CF) and open (OF) canopy natural forest patches and Pinus taeda plantations at harvest age (PP). Structural changes in the natural forest had a profound effect on the ecosystem by halving the forest carbon stock while pulp-intended pine plantations reached the carbon stock of closed forest at harvest age. Main changes from CF to OF were a 55% decrease in the carbon of biomass and a 42% decrease in SOC. Instead, carbon stock density in biomass of PP was similar to CF but the carbon in fallen deadwood was 78% lower while in the litter layer was double; the SOC at 0–5 cm depth was 31% lower in PP than CF. Our study shows that structural changes in the natural forest halve the forest carbon stock while pulp-intended pine plantations can reach the closed forest carbon stock at harvest age. However, PP do not seem to be effective for carbon storage in the long term because of regular harvesting and clearing and their short-life products. Therefore, to effectively store the forest carbon, arresting deforestation, replacement and degradation of the original forest is crucial.

Assisted phoresy of invertebrates by anurans in tank bromeliads: interspecific relationship

Phytotelmata are habitats that house several species. Oftentimes invertebrate species need to disperse themselves sometimes carried by other animals, an interaction called phoresy. Phoresy can be influenced by different factors, therefore, we aim to investigate which factors influence the phoretic potential between anurans and invertebrates from bromeliads in semideciduous Atlantic Forest, as well as whether there is specificity of invertebrates with any anuran species. We tested if (a) phoresy is more common under conditions with higher rainfall; (b) there are some species of anurans that influence the phoresy of invertebrates more than others; (c) size is an important factor to phoresy. The study was developed during six campaigns in two sites containing the bromeliad Aechmea leptantha. In each campaign, water of bromeliads was collected and all anurans found in bromeliads were processed by washing the skin to collect adhered invertebrates. We recorded the prevalence, average intensity and average abundance of invertebrates between anuran species. We verified the similarity of invertebrates between anuran taxa and we tested the hypothesis of independence between them. In order to identify which factors affect phoresy, we performed a GAMLSS analysis. Invertebrates were present on 54.4% of anurans distributed in five species: Dendropsophus decipiens, Scinax pachycrus, S. x-signatus, S. auratus and Pristimantis ramagii. The estimated densities for prevalence, average intensity and average abundance of invertebrates showed distinct shapes among the anuran species, of which not all participate in the same way in invertebrate transport. The mean phoretic potential showed a significant relationship with anuran length and rainfall.

City sloths and marmosets in Atlantic forest fragments with contrasting levels of anthropogenic disturbance

Urbanization is a major threat to wildlife with its cohort of environmental stressors. Urban remnant vegetation can help mitigate these impacts, but such remnants are subject to stressors that might be detrimental for some species. Habitat generalists have flexible diets and broader habitat tolerances that could favour their persistence in these remnants. Marmosets (Callithrix jacchus) and sloths (Bradypus variegatus) differ in their ecological and behavioural plasticity and both occur in urban areas. We predict marmosets to be less affected than sloths, a specialist species, by anthropogenic disturbance. We estimated their densities in urban forest fragments of semi-deciduous Atlantic forest in Paraiba, NE Brazil, with contrasting levels of urbanization. Using the distance sampling methodology, we surveyed 12 trails in a larger and less impacted fragment (515 ha) and 13 trails across nine smaller forest patches (2.1–8.0 ha) with a greater level of anthropogenic disturbance. Density of marmoset’s groups was higher in the area with lower anthropogenic disturbance, whereas sloths’ density was significantly higher in the more urbanized fragments. Marmosets seemed to be more impacted by noise than sloths. The density of both species in forest patches with higher level of anthropogenic disturbance was similar or even higher than densities from non-urban and less disturbed areas. Despite the negative impacts on wildlife, urbanization seems to cause a reduction of predators and an increase in availability of food resources that favour some species. Our results show the importance of small urban forest fragment for the persistence of marmosets and sloths in Neotropical cities.

Aliens in the backyard: Did the American bullfrog conquer the habitat of native frogs in the semi-deciduous Atlantic Forest?

The American bullfrog Lithobates catesbeianus has a natural distribution in North America, but was spread by human activities in different regions around the world. It is listed as the most invasive amphibian species, affecting terrestrial and aquatic ecosystems and the community of native species. In addition, the American bullfrog is extensively associated with lethal pathogens, with high correlation of the presence of this species with population declines and extinctions. Here we test if this alien species has spread through the landscape, establishing populations at new locations. We used diverse methods including georeferencing of satellite images, ethnobiological interviews and field data to evaluate the dispersion and effects of L. catesbeianus introduction on amphibian composition, species number, and density of individuals in forest fragments in an Atlantic Forest landscape. We did not find any relationship between density of individuals, number of species or composition of the native anuran assemblages in forest fragments in relation to the presence or proximity of American bullfrog introduction points. Additionally, we found that the dispersion potential of this species in the studied landscape is zero, as it was only found in those fragments where it was specifically introduced 15 years ago. The species has not established new populations in the landscape. Although exotic, L. catesbeianus thrives in lentic habitats and has no apparent effect on the structural metrics of the native anuran assemblage. Despite this alien species exhibiting a capacity to adapt and survive at the point of introduction, its potential for propagation is limited probably by the fragmented terrestrial landscape and regional stream network.

Spiders (Arachnida: Araneae) in the semideciduous Atlantic Forest: An ecological and morphological trait dataset for functional studies.

BackgroundThe semideciduous Atlantic Forest is one of the most diverse ecosystems in the world with a great diversity of spiders. Most spider-related studies in this ecosystem focused on species richness and composition; however, little is known about their trait diversity (including morphological, ecological and/or physiological traits). Two main datasets were compiled to generate a complete record of spider traits for this ecosystem.New informationHere, we present two datasets about 259 species of spiders from the semideciduous Atlantic Forest of Argentina. The trait data set compiled information of morphological and ecological traits such as body size, femur length, ocular distance, foraging strategy, prey range, circadian activity and stratum preference; traits were assessed by species considering sexual dimorphism. The second dataset included information about phenology (season when spiders were collected), number of individuals assessed by species and presence/absence of spiders in the different sample sites. This dataset has high potential to help researchers in recording the state of a component of biodiversity (functional) and contributes with the study of ecosystem services and species conservation.

Vertical stratification on a small scale: the distribution of fruit-feeding butterflies in a semi-deciduous Atlantic forest in Brazil

ABSTRACT Recently, the availability of cheap and effective survey methods increased the number of forest canopy studies. Several studies have described butterfly communities in the upper forest stratum. However, these studies were all conducted in tall forests (20–60 m canopy height). Here we aim to assess the stratification of fruit-feeding butterfly species in two vertical strata of a semi-deciduous seasonal forest. In addition, we present a field guide to assist in future butterfly monitoring. This study was carried out in two areas of semi-deciduous seasonal forest in the Serra da Bodoquena National Park, Mato Grosso do Sul State, Brazil. Sampling monthly for a year both the, canopy and the understory, we recorded 4229 individuals of 65 species. The species community of fruit-feeding butterflies showed a clear vertical stratification. The composition differed significantly between the two vertical strata, with a higher species richness and abundance in the understory, but less diversity compared to the canopy. Species were distributed heterogeneously between the understory and the canopy in this forest of lower canopy height. Considering published literature of the Mato Grosso do Sul State, the Serra da Bodoquena is one of the most species rich areas with regard to fruit-feeding butterflies.

Trace element leaf accumulation in native trees from the remaining Semideciduous Atlantic Forest in Brazil

Remnants of Semideciduous Atlantic Forest surrounded by numerous industries, intense road traffic and agricultural lands in Southeast Brazil have been affected by trace elements. We implemented a passive biomonitoring with the three most abundant native tree species (Astronium graveolens, Croton floribundus and Piptadenia gonoacantha) to answer these questions: 1) which species has the greatest potential to accumulate trace elements?; 2) does the leaf accumulation level of trace elements vary between the edge and interior of the forest remnants, between dry and wet periods or due to the distance from the industrial area?; 3) which species, among the most abundant in the forest remnants, would better indicate the spatial variations in trace elements pollution and which elements would be the most relevant for such spatial discrimination? Leaf samples were collected during the dry and wet seasons, at the edge and interior of four forest remnants. Trace elements were determined using inductively coupled plasma mass spectrometry (ICP MS). Few edge effects were evidenced in the leaf concentrations in all species. Higher concentrations of most trace elements were measured during dry season. Although C. floribundus showed the most accumulating capacity, A. graveolens was the most appropriate species to discriminate spatial variations. The forest closer to the industrial area was distinguished from the others by Mn and Ni from oil burning, but the metal pollution from the industrial area did not interfere on the leaf concentrations in A. graveolens sampled in the urban and rural forests.

From dropping to dropping: The contribution of a small primate to seed dispersal in Atlantic Forest

The dynamic interaction between animals and plants through frugivory and seed dispersal is one of several ecological processes that modulates tropical biodiversity. Here we evaluated the potential role of a highly-frugivorous Neotropical primate, the black-fronted titi monkey (Callicebus nigrifrons), as seed disperser. We studied two titi monkey groups in semideciduous Atlantic Forest remnants. Each group fed on over 49 zoochorous plant species in about one year and ingested seeds from nearly a half of them, especially those with small seeds (<0.5 cm). The groups of titi monkeys defecated a large number of seeds, reaching over 300 seeds per day (1–305). More than half of the total deposited seeds and seed species germinated after gut passage, however gut passage reduced germination success in three of five evaluated species. Feces were deposited in small clumps distributed across groups’ home range. We suggest that the observed distribution pattern of feces may enhance plant reproductive fitness by increasing the probability of seeds being deposited far from parent plants, in novel and favorable sites. We concluded that the seed handling and deposition behavior of black-fronted titi monkey make this primate an important agent for Atlantic forest regeneration.

Urban forest fragments as unexpected sanctuaries for the rare endemic ghost butterfly from the Atlantic forest.

Anthropogenic land expansion, particularly urbanization, is pervasive, dramatically modifies the environment and is a major threat to wildlife with its associated environmental stressors. Urban remnant vegetation can help mitigate these impacts and could be vital for species unable to survive in harsh urban environments. Although resembling nonurban habitats, urban vegetation remnants are subject to additional environmental stresses. Here, we evaluate the occurrence and density of the endemic ghost butterfly (Morpho epistrophus nikolajewna) that was once common, in the highly fragmented Atlantic forest of NE Brazil. We tested whether this butterfly would be found at lower densities in urban forest fragments of contrasting sizes as opposed to rural ones, given the number of environmental stressors found in urban areas. We surveyed 14 forest fragments (range 2.8 to over 3,000 ha) of semideciduous Atlantic forest in rural and urban locations using transect based distance sampling. The ghost butterflies showed strong seasonality; flying only from April to June. They were only identified in an urban fragment (515 ha), with an estimate of 720 individuals and a density 1.4 ind/ha. All forest fragments had experienced some level of logging in the past, which might have had an effect in the butterfly population. Nevertheless, rural forest fragments were subject to increased particulate matter concentrations, associated to biomass burning that we suggest might have had a more influential role driving the collapse of rural populations. Our findings show the importance of urban forest remnants to sustain population of this endangered species.