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Made available in DSpace on 2021-06-25T10:18:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Comunidad de Madrid Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Ministerio de Economía, Industria y Competitividad, Gobierno de España Temporal scale in animal communities is often associated with seasonality, despite the large variation in species activity during a diel cycle. A gap thus remains in understanding the dynamics of short-term activity in animal communities. Here we assessed calling activity of tropical anurans and addressed how species composition varied during night activity in assemblages along gradients of local and landscape environmental heterogeneity. We investigated 39 anuran assemblages in the Pantanal wetlands (Brazil) with passive acoustic monitoring during the peak of one breeding season, and first determined changes in species composition between night periods (early, mid and late) using two temporal resolutions (1- and 3-hr intervals). Then, we addressed the role of habitat structure (local and landscape heterogeneity variables from field-based and remote sensing metrics) and ecological context (species richness and phylogenetic relatedness) in determining changes in species composition (a) between night periods and (b) across days. Nocturnal calling activity of anuran assemblages varied more within the 1-hr resolution than the 3-hr resolution. Differences in species composition between early- and late-night periods were related to local habitat structure and phylogenetic relatedness, while a low variation in compositional changes across days was associated with low-heterogeneous landscapes. None of these relationships were observed using the coarser temporal resolution (3 hr). Our findings on the variation of calling activity in tropical anuran assemblages suggest potential trade-offs mediated by fine-temporal partitioning. Local and landscape heterogeneity may provide conditions for spatial partitioning, while the relatedness among co-signalling species provides cues on the ecological overlap of species with similar requirements. These relationships suggest a role of niche dimensional complementarity on the structuring of these anuran assemblages over fine-temporal scales. We argue that fine-temporal differences between species in breeding activity can influence the outcome of species interaction and thus, addressing temporal scaling issues can improve our understanding of the dynamics of animal communities. Instituto de Biociências Universidade Estadual Paulista (Unesp) Terrestrial Ecology Group Departamento de Ecología Universidad Autónoma de Madrid Ciudad Universitaria de Cantoblanco Facultad de Ciencias Biología Centro de Investigación en Biodiversidad y Cambio Global Universidad Autónoma de Madrid Ciudad Universitaria de Cantoblanco Biological and Environmental Sciences Faculty of Natural Sciences University of Stirling Laboratório de Herpetologia e Comportamento Animal Departamento de Ecologia Instituto de Ciências Biológicas Universidade Federal de Goiás Instituto de Biociências Universidade Estadual Paulista (Unesp) FAPESP: 2013/50421-2 FAPESP: 2015/25316-6 Comunidad de Madrid: 2016-T2/AMB-1722 FAPESP: 2017/15772-0 FAPESP: 2019/04033-7 CNPq: 310144/2015-9 CAPES: 817737/2015 CAPES: 88881.068425/2014-01 Ministerio de Economía, Industria y Competitividad, Gobierno de España: CGL2017-88764-R Ministerio de Economía, Industria y Competitividad, Gobierno de España: PEJ2018-004603-A

The reproduction is one of the main events in the life of an organism, and anurans stand out among vertebrates because of the diversity of their reproductive strategies. We studied the reproduction of two syntopic species, Physalaemus aff. albonotatus and P. santafecinus, and comparatively described their reproductive activity pattern, advertisement calls, calling sites, daily calling activity, amplexus behavior, foam nests, and microhabitats in foam nests. In regards to the reproductive activity pattern, both species were defined as prolonged breeders. However, P. santafecinus exhibited a behavior like explosive breeders: it had a faster reproductive response against rains than P. aff. albonotatus. The calling activity was restricted exclusively to night hours in P. santafecinus, whereas P. aff. albonotatus called during both night and day. The advertisement calls of both species showed a rich harmonic structure, and were characterized by a bimodal harmonic dominance. The species differed significantly in microhabitat calling sites, foam nests, and microhabitats in foam nests. Namely, P. santafecinus frequently called and constructed its nests in sites more exposed than those of P. aff. albonotatus. The general differences in reproductive behaviors observed between the species principally agree with their different reproductive activity patterns., Facultad de Ciencias Naturales y Museo

The abstract is available here: https://uscholar.univie.ac.at/o:1005828

Acoustic segregation is a way to reduce competition and allows for species coexistence within anuran communities. Thus, separation in at least one acoustic niche dimension is expected, which also contributes to achieving effective communication among frogs. Here we studied an assemblage of five terrestrial egg-laying anuran species, all in the genus Eleutherodactylus, in a montane rainforest in eastern Cuba. Our aim was to determine if partitioning exists between these species in any dimension (time, signal frequency or space) of the acoustic niche. The studied assemblage had the following characteristics: (1) there was one diurnal species, two species with calling activity throughout the day and two species that call at night; (2) only two species overlapped in call frequencies and most had different calls, both in terms of dominant frequencies and in temporal characteristics; and (3) males of the species that overlapped in vocalizing time or signal frequency used different calling microhabitats or heights. This study provides evidence for the acoustic niche hypothesis in anurans, showing low probabilities of interference in sound communication among these frogs. The five species were separated in at least one of the three acoustic dimensions (calling time, frequency and site) as it occurs in mainland communities with more sympatric species of several genera. Conversely, species in single-genus communities studied in Puerto Rico overlapped completely in calling times. This seems to be due to the higher number of sympatric species at our site. The fieldwork was partially supported by a Seed Grant from the Declining Amphibian Population Task Force (DAPTF) to AFG.

Temporary pools are important resources for animals that have aquatic stages during their life history, and particularly for those living in dry climate regions. We investigated the breeding activity of an anuran assemblage in a small temporary pond in the Ampijoroa dry forest of Ankarafantsika National Park, northwestern Madagascar, during the first half of the rainy season from 2000 to 2001 and during the entire rainy season and the beginning of the dry season from 2003 to 2004. We also surveyed the anuran fauna of Ampijoroa throughout the long-term research conducted from 1999 to 2014. We estimated the breeding activity based on the calling intensity of male frogs. A total of 12 species of frogs was recorded, and eight out of them were confirmed to breed in the temporary pond. These eight species consisted of five families, including one introduced species. The initiation of calling activity seemed to be affected by rainfall in several species. Five of the eight species (Ptychadena mascareniensis, Boophis doulioti, Blommersia wittei, Heterixalus luteostriatus and H. tricolor) were considered prolonged breeders, and the other three (Laliostoma labrosum, Hoplobatrachus tigerinus, and Dyscophus insularis) were considered explosive breeders. Two species (Mantidactylus ulcerosus and Stumpffia sp.) were not observed to use the temporary pond for their breeding sites. Neither calls nor breeding sites of the remaining two species (Scaphiophryne calcarata and Mantella ebenaui) were confirmed, although they have been described to breed in stagnant water. This study indicates that temporary ponds in the Ampijoroa forest, which are quite limited in number, provide important habitat for reproduction of frogs, which are living in a harsh environment.

Um levantamento da anurofauna foi realizado na Fazenda Jaburi (11° 35’-11° 38’ S e 60° 41-60° 45’ W), Município de Espigão do Oeste, Estado de Rondônia, Brasil, analisando a distribuição espacial e período da atividade de vocalização das espécies registradas em áreas de floresta primária e de pastagem. O trabalho de campo na Fazenda Jaburi foi realizado entre fevereiro de 2001 e março de 2002. Para amostragem das espécies, diferentes ambientes foram investigados intensivamente por procura ativa e também por armadilhas de interceptação e queda. Um total de 47 espécies, pertencentes a dez famílias foi registrado: Aromobatidae (1), Brachycephalidae (2), Bufonidae (4), Centrolenidae (1), Cycloramphidae (1), Dendrobatidae (1), Hylidae (23), Leiuperidae (1), Leptodactylidae (8) e Microhylidae (5). Novos registros para o Estado de Rondônia são as seguintes espécies: Dendropsophus acreanus, Trachycephalus resinifictrix, Chiasmocleis bassleri e C. ventrimaculata. A maioria das espécies apresentou atividade de vocalização durante o período chuvoso (outubro a março), e houve correlação significativa entre a atividade de vocalização e a pluviosidade. Foi encontrada a maior riqueza de espécies nas áreas de floresta do que nas de pastagem, podendo ser um indicativo de que o desmatamento pode provocar a diminuição da riqueza de espécies. A survey of the anuran fauna was carried out in the Jaburi farm (11° 35’-11° 38’ S and 60° 41-60° 45’ W), Municipality of Espigão do Oeste, Rondônia State, Brazil, analysing spatial distribution and calling activity period of the species in primary forest and pasture areas. Field work at Jaburi farm was carried out from February 2001 until March 2002. For sampling of the species, different environments were investigated extensively throughout searching frogs in breeding sites and catching by pitfalls traps. A total of 47 species out of ten families were recorded: Aromobatidae (1), Brachycephalidae (2), Bufonidae (4), Centrolenidae (1), Cycloramphidae (1), Dendrobatidae (1), Hylidae (23), Leiuperidae (1), Leptodactylidae (8) and Microhylidae (5). New registers for Rondônia State were the following species: Dendropsophus acreanus, Trachycephalus resinifictrix, Chiasmocleis bassleri e C. ventrimaculata. The majority of species called during rainy period (October to March), and there was a significant correlation between calling activity and rainfall. More anuran species were found within the forest than on pasture areas, showing that deforestment may decrease number of species.

Anuran communication is dominated by acoustic signals; consequently, most species have well-developed vocal systems that can produce a variety of sounds in different situations (Duellman and Trueb 1986). The advertisement call is the most commonly emitted sound in this repertoire; males produce this vocalization in both reproductive and territorial contexts (Gerhardt 1994, Wells 2007), and it usually is accompanied by the inflation of a vocal sac with pulmonary air (Pauly et al. 2006). Vocal sacs occur widely in anurans and are thought to be involved in both acoustic and visual communication (Narins et al. 2003, Rosenthal et al. 2004).

We describe the breeding biology and the advertisement call of the horned leaf-frog, Proceratophrys appendiculata (Günther, 1873) in the Parque Nacional da Serra dos Órgãos, municipality of Teresópolis. The reproductive period of P. appendiculata is short and is associated with the end of the winter and the beginning of the spring, when males call night and day under large rocks in sandy bottom rock streams. The amplexus is axillary and one female laid about 656 viscous eggs. The advertisement call of P. appendiculata is unique among congeners. The call lasts approximately two seconds, with about 85 pulses/call at a rate of 45 pulses/s and frequency around 0.620 kHz. It is one of the longest calls and lowest in dominant frequency. Moreover, the call of P. appendiculata is characterized by the greatest number of pulses so far registered, reaching 129 pulses in a single call.

Global climate change has been implicated in phenological shifts for a variety of taxa. Amphibian species in particular are sensitive to changes in their environment due to their biphasic life history and restricted reproductive requirements. Previous research has shown that not all temperate amphibian species respond similarly to the same suite of climatic or environmental cues, nor are individual species necessarily uniform in their responses across their range. We examined both the timing of spring emergence and calling phenology of eight anuran species in southeastern Ontario, Canada, using an approximately 40-year dataset of historical records of amphibian activity. Rana pipiens was the only species out of eight considered to emerge significantly earlier, by an estimated 22 days over four decades. Both R. pipiens and Bufo americanus have advanced initiation of calling over a four-decade span significantly earlier by an estimated 37.2 and 19.2 days, respectively. Rana sylvatica showed a trend toward earlier emergence by 19 days, whereas we did not detect changes in emergence phenology for the remaining five species. This significant shift in breeding behavior for two species correlates to significant regional increases in spring temperatures of an estimated 2.7-2.8°C overall over four decades. Our study suggests that local temperature increases have affected the timing of emergence and the onset of calling activity in some Ontario anuran species. Global decline or range shifts ultimately may be related to changes in reproductive behavior and timing mediated by shifting climate.

We examined the effects of predator-prey distance (PPD) and trajectory of the predator on the body patterns that the pharaoh cuttlefish, Sepia pharaonis, shows in response to a predator. A model predator moving in three different trajectories was presented to the cuttlefish: T1, approached the cuttlefish but bypassed above; T2, approached directly toward the cuttlefish; T3, bypassed the cuttlefish both vertically and horizontally. We divided the body patterns that the cuttlefish expressed into seven categories, i.e., "uniform light", "disruptive", "center circle", "dark square", "vertical stripe", "all dark" and "eyespots". In T1, the number of individuals that showed "dark square" increased as the model approached the cuttlefish, whereas the number of individuals that showed "disruptive" decreased. In T2, the number of individuals that showed "all dark" and "eyespots" increased as the model approached the cuttlefish. In T3, the number of individuals that showed "dark square" and "vertical stripe" increased as the model approached the cuttlefish, and it tended to decrease as the model receded from the cuttlefish. These results demonstrate that S. pharaonis changes its body patterns according to PPD and the trajectory of the predator, which would affect predation risk and/or predator perception.