Richness, abundance, and mass in snake assemblages from two Atlantic Rainforest sites (Ilha do Cardoso, São Paulo) with differences in environmental productivity

Birds of Parque Estadual Ilha do Cardoso: ecology, conservation and natural history

Abstract: The Parque Estadual Ilha do Cardoso (PEIC), located on extreme South of São Paulo’s cost, in Brazil, holds an important Atlantic Forest remnant which still in a good state of conservation, but lack a deepen study about the avian community that habits the island. This study aimed to elaborate a census of avian species that occur in the park approaching richness, occurrence frequency, occurrence status and the structure of trophic guilds. A total of 25 field expedictions occurred between September 2015 and September 2017 during five days each, the field work included different ecosystems as mangrove, restinga, forest, sandbank, beach and marine. The census was made combine three different techniques used in ornithological studies: visual identification, auditory identification and catch by mist-nets (with five fixed sites in mangrove, restinga and forest). Were recorded 335 avian species, with 28 of them endemic from Brazil and 33 being threatened with extinction. Seventy-three species were recorded in all sampled months (FO 100%), while 46 were recorded in just one month (FO = 4%). About occurrence status, 55% of species are residents, 20% occasional visitors, 13% unusual residents, 6% migratory and 6% visitors. According the recorded species were recognized 25 trophic guilds based on food items, corporal size and strata that commonly forage, which of most representative in the community, the guild of “of insectivorous of medium-strata” (N = 55), “canopy omnivorous” (N = 33), “aquatic invertebrates consummers” and “piscivorous” (N = 31). Finally, with the current study, we aimed through a significative field effort bring a better knowledge about avifauna of PEIC, which could be a good base when is necessary take actions that aim to park management and the Conservation Unities around it.

Integrating human behavior and snake ecology with agent-based models to predict snakebite in high risk landscapes

Snakebite causes more than 1.8 million envenoming cases annually and is a major cause of death in the tropics especially for poor farmers. While both social and ecological factors influence the chance encounter between snakes and people, the spatio-temporal processes underlying snakebites remain poorly explored. Previous research has focused on statistical correlates between snakebites and ecological, sociological, or environmental factors, but the human and snake behavioral patterns that drive the spatio-temporal process have not yet been integrated into a single model. Here we use a bottom-up simulation approach using agent-based modelling (ABM) parameterized with datasets from Sri Lanka, a snakebite hotspot, to characterise the mechanisms of snakebite and identify risk factors. Spatio-temporal dynamics of snakebite risks are examined through the model incorporating six snake species and three farmer types (rice, tea, and rubber). We find that snakebites are mainly climatically driven, but the risks also depend on farmer types due to working schedules as well as species present in landscapes. Snake species are differentiated by both distribution and by habitat preference, and farmers are differentiated by working patterns that are climatically driven, and the combination of these factors leads to unique encounter rates for different landcover types as well as locations. Validation using epidemiological studies demonstrated that our model can explain observed patterns, including temporal patterns of snakebite incidence, and relative contribution of bites by each snake species. Our predictions can be used to generate hypotheses and inform future studies and decision makers. Additionally, our model is transferable to other locations with high snakebite burden as well.

Reptiles of the Serra das Torres Natural Monument: using the Rapid Assessment method to fill a knowledge gap in the Atlantic Forest of southeastern Brazil

Abstract: Data on the composition of local reptile assemblages in several Brazilian ecosystems can still be considered relatively restricted in scope in most cases. In this study, we conducted surveys in the Serra das Torres Natural Monument, located in the municipalities of Atílio Vivacqua, Muqui, and Mimoso do Sul, using the Rapid Assessments method (RAP) during 30 days in the rainy season of 2018. We sampled actively for approximately 1320 hours with a 6-10 person crew, supplemented by 720 hours of passive sampling (30 bucket-days) using pitfall traps with drift fences. We recorded 34 reptile species during our sampling method (2 amphisbaenid, 11 lizards, and 21 snakes) and an occasional encounter, after the end of sampling, that added a chelonian species to the list, Hydromedusa maximiliani, totaling 35 reptile species. The Dipsadidae was the family with the greatest snake species richness and, the Gymnophtalmidae had the greatest lizard species richness. The species richness recorded in the Serra das Torres Natural Monument (Ntotal = 35) represents ca. 27% of all reptile species found in the state of Espírito Santo (N = 130). The most abundant lizard species was Leposoma scincoides followed by Ecpleopus gaudichaudii and, the most abundant snake species was Bothrops jararaca being markedly higher than that recorded in similar studies. Twenty-seven percent of the reptile species recorded in our study are endemic to the Atlantic Forest and 30% (N = 10) have been recorded less than five times previously in the Brazilian state of Espírito Santo. Our study reinforces the need for the conservation of the Serra das Torres Natural Monument because of its importance as a reservoir of a considerable portion of the reptile biodiversity of Espírito Santo state, and of the Atlantic Forest biome as a whole.

Area and distance from mainland affect in different ways richness and phylogenetic diversity of snakes in Atlantic Forest coastal islands

AIM

The Theory of Island Biogeography posits that ecological and evolutionary processes regulate species richness of isolated areas. We assessed the influences of an island area and distance from the mainland on species richness, phylogenetic diversity, and phylogenetic composition of snakes on coastal islands.

LOCATION

Coastal islands of the megadiverse Atlantic Forest in southeastern Brazil.

METHODS

We compiled the species composition of 17 coastal islands in southeastern Brazil. Species richness and phylogenetic diversity were calculated for each island. Phylogenetic composition was measured using principal coordinates of phylogenetic structure. We then employed generalized linear models to test the influence of area and distance from the mainland on the diversity metrics.

RESULTS

We found a prominent influence of area on species richness, whereas phylogenetic diversity was more affected by distance from the mainland. Snake clades were distinctly associated with area and distance. The Boidae family was associated with nearer and larger islands, whereas Elapidae was broadly distributed. Distance from the mainland was associated with the distribution of Dipsadidae, whereas Colubridae was influenced by both the area and distance. The Viperidae family attained higher values of phylogenetic diversity in smaller and more remote islands.

MAIN CONCLUSIONS

This island system conserved a considerable piece of snake richness from southeastern Brazil, including island endemic species. Area and distance from the mainland were important drivers of snake diversity in the Atlantic Forest coastal islands. However, these predictors affected the different components of diversity in different ways. Phylogenetic composition analysis enables us to understand how basal nodes contributed to high levels of phylogenetic diversity on smaller and farther islands regardless of the decrease in species richness.

Composition and natural history of the snakes from the Parque Estadual da Serra do Papagaio, southern Minas Gerais, Serra da Mantiqueira, Brazil

The Serra da Mantiqueira is one of the least inventoried physiographic areas of southeastern Brazil. There is great potential for detection of endemic species for which little or nothing is known about basic aspects of natural history. The Parque Estadual da Serra do Papagaio (PESP) within the Serra da Mantiqueira is an area of extreme biological importance because it houses mixed formations of grasslands, ombrophilous forests, and enclaves of Araucaria forests (mixed ombrophilous forest). Currently, the mixed ombrophilous forest covers less than 5% of its original range and areas occupied by this forest type, and associated ecosystems constitute refuges, housing several endemic, high altitude species. Between September 2015 and April 2016, field samplings were performed in the PESP using four distinct methods. The objective was to determine the composition and natural history of snakes from an isolated, high altitude area of the Serra da Mantiqueira. In PESP and surrounding areas, 80 individuals representing 24 species, 19 genera, and three families were recorded. Data are presented on abundance, habitat, daily activity, diet, reproduction, and defense. Comparison of the PESP snake assemblage with 30 other Atlantic Forest areas in southeastern Brazil indicate the Serra da Mantiqueira presents particular characteristics regarding snake composition.

Snake assemblage of Estação Ecológica de Santa Bárbara, SP: a Cerrado remnant in Southeastern Brazil

Despite the great extension of the Cerrado and its importance for biodiversity conservation, there are still sampling gaps in this region that has shown conspicuous changes over the years due to the conversion of natural areas into pastures and plantations. Around 88.5% of the Cerrado areas in the State of the São Paulo were cleared in the last four decades and less than 0.81% of the original Cerrado vegetation remains as pristine habitats, although these areas once covered 14% of the state. We present the list of snakes that occur in the Estação Ecológica de Santa Bárbara, a remnant of Cerrado in the State of São Paulo, in addition to information on the abundance and distribution of species in the various habitats found at this location. The survey was conducted between October 2008 and March 2009 during six monthly field trips of five days each, totaling 30 sampling days. Surveys were conducted using incidental encounters (IE) and pitfall traps (PT). We recorded a total of 21 species belonging to 15 genera and six families. All species and individuals captured (18 species; 49 individuals) were found in open Cerrado formations. No individual was observed in the sampled forest habitats (cerradão and dry forest). Forested habitats occupy a relatively small portion of this protected area (12.6%). However, the higher species richness in open habitats may not be a result of limited local coverage of forests. The higher richness in interfluvial open habitats has also been recorded in other Cerrado areas. This survey is an important contribution towards enhancing our knowledge about the snake assemblage in the highly threatened Cerrado of São Paulo State. Hence, these last protected remnants in the state that still house significant areas of open Cerrado formations, such as the Estação Ecológica de Santa Bárbara, although reduced, are extremely important for the conservation of reptiles in the State of São Paulo, in Southeastern Brazil, and in the Cerrado region.