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1.
Ecology ; 99(7): 1692, 2018 07.
Article in English | MEDLINE | ID: mdl-29953585

ABSTRACT

Amphibians are among the most threatened vertebrates in the world and this is also true for those inhabiting the Atlantic Forest hotspot, living in ecosystems that are highly degraded and threatened by anthropogenic activities. We present a data set containing information about amphibian communities sampled throughout the Atlantic Forest Biome in South America. The data were extracted from 389 bibliographic references (articles, books, theses, and dissertations) representing inventories of amphibian communities from 1940 to 2017. The data set includes 17,619 records of 528 species with taxonomic certainty, from 1,163 study sites. Of all the records, 14,450 (82%) were classified using the criterion of endemism; of those, 7,787 (44%) were considered endemic and 6,663 (38%) were not. Historically, multiple sampling methods were used to survey amphibians, the most representative methods being active surveys (82.1%), surveys at breeding sites (20%), pitfall traps (15.3%), and occasional encounters (14.5%). Species richness averaged 15.2 ± 11.3 (mean ± SD), ranging from 1 to 80 species per site. We found a low dominance in the communities, with 10 species occurring in about 26% of communities: Physalaemus cuvieri (4.1%), Dendropsophus minutus (3.8%), Boana faber (3.1%), Scinax fuscovarius (2.8%), Leptodactylus latrans (2.7%), Leptodactylus fuscus (2.6%), Boana albopunctata (2.3%), Dendropsophus nanus (1.6%), Rhinella ornata (1.6%), and Leptodactylus mystacinus (1.6%). This data set represents a major effort to compile inventories of amphibian communities for the Neotropical region, filling a large gap in the data on the Atlantic Forest hotspot. We hope this data set can be used as a credible tool in the proposal of new studies on amphibian sampling and even in the development of conservation planning for these taxa. This information also has great relevance for macroecological studies, being foundational for both conservation and restoration strategies in this biodiversity hotspot. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or teaching events.


Subject(s)
Ecosystem , Forests , Amphibians , Animals , Anura , Biodiversity , Brazil , South America
2.
J Therm Biol ; 74: 77-83, 2018 May.
Article in English | MEDLINE | ID: mdl-29801654

ABSTRACT

As ectotherms, amphibians may exhibit changes in their thermal biology associated with spatial and temporal environmental contingencies. However, our knowledge on how amphibian´s thermal biology responds to seasonal changes in the environment is restricted to a few species, mostly from temperate regions, in a marked contrast with the high species diversity found in the Neotropics. We investigated whether or not the seasonal variation in climatic parameters from a high-montane ombrophilous forest in the Brazilian Atlantic Forest could lead to concurrent adjustments in the thermal biology of the terrestrial toad Rhinella icterica. We measured active body temperature (Tb) in the field, and preferred body temperature (Tpref) and thermal tolerance (critical thermal minimum, CTmin, and maximum, CTmax) in the laboratory, for toads collected at two distinct seasons: warm/wet and cold/dry. We also measured operative environmental temperatures (Te) using agar toad models coupled with dataloggers distributed in different microhabitats in the field to estimate accuracy (db) and effectiveness (E) of thermoregulation of the toads for both seasons. Toads had higher Tpref in the warm/wet season compared to the cold/dry season, even though no seasonal change occurred in field Tb's. In the warm/wet season, toads decreased the accuracy of thermoregulation and avoided thermally favorable microhabitats, while in the cold/dry season they increased the accuracy of thermoregulation and exhibited high degree of thermoconformity. This result may encompass thermoregulatory adjustments to seasonal changes in Te's, but may also reflect seasonal differences in compromises between Tb regulation and other ecologically relevant activities (reproduction, foraging). Toads did not exhibit changes in CTmin or CTmax, which indicates a low risk of exposure to extreme temperatures in this particular habitat, at both seasons, possibly combined with a low flexibility of this trait. Overall, our study shows seasonal acclimatization in some aspects of the thermal biology of the toad, R. icterica.


Subject(s)
Acclimatization , Body Temperature Regulation , Bufonidae/physiology , Animals , Brazil , Female , Forests , Male , Seasons , Temperature , Thermotolerance
3.
Biota neotrop. (Online, Ed. port.) ; 10(4): 257-274, Oct.-Dec. 2010. ilus, mapas, tab
Article in English | LILACS-Express | LILACS, Sec. Est. Saúde SP | ID: lil-578505

ABSTRACT

The herpetofauna of São Paulo State, Brazil, can be characterized as the most well-known in the country. However, despite the large number of studies in this area, there are still many sampling gaps within biomes such as the Atlantic Forest that are considered global conservation priorities due to the high rate of endemism and human disturbance. As a result of political and historical pressure, this biome has been reduced to less than 12 percent of its original extent and, despite its importance for global biodiversity conservation, only a small percentage of its original vegetation cover (1 percent) has some form of legal protection. This is the case of the Parque Estadual Turístico do Alto Ribeira (PETAR) which, together with the Parque Estadual de Intervales, Parque Estadual Carlos Botelho and Mosaico de Unidades de Conservação de Jacupiranga, forms of an ombrophilous forest continuum of 360 thousand ha in the south of São Paulo State. This study presents a list of amphibians and reptiles from the PETAR, with information on the local distribution and habitat use of the species. The survey was conducted from October to December 2009, completing a total of 15 sampling days using four complementary methods of active sampling: visual encounters, auditory encounters, searches by car and incidental encounters. We recorded a total of 91 species belonging to 53 genera and 24 families. This high diversity can be attributed to the existence of a wide variety of habitats and microhabitats in this region, such as the various aquatic sites used by many species of anuran amphibians. Moreover, the PETAR features a large altitudinal gradient (80 - 1,160 m elevation) that gives a large climatic, geological and hydrological heterogeneity to the area. This inventory is an important contribution to the expansion of knowledge about these assemblages in the Atlantic Forest to the south of Serra de Paranapiacaba mountain range, and provides support for the conservation of these groups in São Paulo State.


Apesar do grande número de estudos realizados com a herpetofauna do Estado de São Paulo, que a caracteriza como a mais conhecida no país, ainda existem vazios amostrais dentro de biomas considerados mundialmente como prioritários para a conservação pelo elevado grau de endemismo e pressão antrópica, como é o caso da Mata Atlântica. Como resultado de pressões políticas e históricas, o bioma foi reduzido a menos de 12 por cento de sua extensão original e apesar de sua importância para a conservação da biodiversidade mundial, apenas uma porcentagem mínima de sua cobertura vegetal original (1 por cento) encontra-se protegida sob alguma forma legal de proteção. Este é o caso do Parque Estadual Turístico do Alto Ribeira (PETAR) que juntamente com o Parque Estadual de Intervales, Parque Estadual Carlos Botelho e Mosaico de Unidades de Conservação de Jacupiranga formam um extenso contínuo ecológico de 360 mil ha de floresta ombrófila no sul do estado. O presente estudo apresenta a lista de anfíbios e répteis do PETAR, com informações sobre a distribuição local e uso de hábitat destas espécies. O inventário foi realizado de outubro a dezembro 2009, totalizando 15 dias de amostragens que foram realizadas por meio de quatro métodos complementares de amostragem ativa: procura visual, procura auditiva, procura de carro e encontro ocasional. Foram registradas no total 91 espécies pertencentes a 53 gêneros e 24 famílias. Esta alta diversidade pode ser atribuída à existência de uma grande variedade de hábitats e microhábitats nesta localidade, como os diversos sítios aquáticos utilizados por várias das espécies de anfíbios anuros amostradas. Além disso, o PETAR apresenta um amplo gradiente altitudinal (80 - 1.160 m) que confere uma grande heterogeneidade climática, geológica e hidrológica a área. Neste sentido, este inventário é uma importante contribuição para a ampliação do conhecimento destas taxocenoses de floresta ombrófila presentes na porção mais ao sul da Serra de Paranapiacaba, fornecendo subsídios para a adoção de medidas visando à conservação dessas taxocenoses no Estado de São Paulo.

4.
São José do Rio Preto; s.n; Jul. 2009. 128 p.
Thesis in Portuguese | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1079160

ABSTRACT

Dada a importância da temperatura na maior parte dos processos biológicos, estudos sobre a termorregulação têm desempenhado importante papel no entendimento sobre a ecologia dosvertebrados ectotérmicos. Em serpentes, como em outros ectotérmicos, o controle da temperaturacorpórea (Tc) é dependente da utilização de fontes externas de calor e principalmente de ajustescomportamentais, embora ajustes fisiológicos e morfológicos também ocorram. Em geral, esse controle é alcançado por meio da escolha de ambientes quentes ou frios, cuja disponibilidade pode variar ao longo do dia e das estações do ano. A termorregulação, portanto, constitui aspecto central da biologia das serpentes, as quais dedicam porção considerável de seu tempo e energia a essa atividade. Os objetivos do presente estudo foram documentar a variação sazonal e circadiana da temperatura corpórea da jararaca-ilhoa, Bothrops insularis, em seu ambiente natural, a Ilha da Queimada Grande (IQG), a fim de prover análise descritiva da Tc e do comportamento termorregulatório destes animais à luz dos custos e benefícios da regulação da Tc na região tropical; e entender como estes parâmetros são ditados/influenciados por fatores ambientais (temperatura local e de microhábitats, umidade relativa, precipitação, radiação solar, vento, características do substrato) e bióticos (tamanho dos indivíduos, sexo, estágio reprodutivo, estadodigestivo)...


Given the pervasive effects of temperature on most biological processes, studies focusing onthermoregulation are pivotal to the understanding of ectotherm’s vertebrate ecology. In snakes, like other ectotherms, body temperature (Tb) control is dependent of external heat sources and based mainly on behavioral adjustments, although physiological and/or morphological adjustments can also occur. In general, such control is achieved through the choice of warm or cold environments, whose availability may vary along the days and/or seasons. Thus, thermoregulation can be regarded as a central aspect of snake biology, and these animals invest considerable time and energy into this activity. The aims of the present study were to document the seasonal and circadian variation in the Tb’s of the golden lancehead, Bothrops insularis, in its natural habitat, the Queimada Grande Island (QGI). We then used such database to provide a descriptive analysis of Tb variation and thermoregulatory behavior for this species in the light of the costs-benefitstheory applied to a tropical region. Our second goal was to understand how body temperature is dictated/influenced by environmental (local and microhabitat temperatures, relative humidity, precipitation, solar radiation, wind, substrate characteristics) and biotic factors (individual size, sex, reproductive stage, digestive state)...


Subject(s)
Animals , Bothrops/classification , Bothrops/metabolism , Snakes/classification , Temperature , Body Temperature , Ecology , Viperidae
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