Patrick Colombo

Composição e ameaças à conservação dos anfíbios anuros do Parque Estadual de Itapeva, município de Torres, Rio Grande do Sul, Brasil

A species inventory is the first step to develop conservation strategies. The Itapeva State Park (PEVA) is a protected area located in a narrow zone between RS-389 (Estrada do Mar) and the Itapeva beach, near Torres city, extreme north of the coastal plain of the Rio Grande do Sul State (29° 21 S and 49° 45 W). The Park is covered by mobile dunes, fixed dunes, marshy forest, grasslands, dry forests, wetlands and streams. The aim of this study is to list the anuran species of PEVA, to describe their habitats, and to identify possible impact on these anurans inside the Park. The anuran fauna survey occurred from March 2000 to March 2003. The field trips were monthly from May de 2000 to March 2001 after this period, eigth adicional field trips were done. The surveys comprised two nights and two days. The sampling methods included periodic visits to all environments with potential anuran incidence, wet areas, pools, temporary pools, streams and wetlands. During the day we looked for animals under logs, stones, tiles, and near houses. Nocturnal collections were from 8:00 to 11:00 PM. Eight environments were sampled: primary sand dunes (DP), wetlands (BD), movel dunes (DM), fixed dunes (DF), wet grasslands (CA), capoeira (regenerating forest), (CP), marshy forest (MP) and dry grasslands (CS). Twenty-nine anuran species from eight families were recorded: Hylidae (11 spp.), Leiuperidae (6 spp.), Bufonidae (4 spp.), Leptodactylidae (3 spp.), Brachycephalidae (2 spp.), Cycloramphidae (1 sp.), Microhylidae (1 sp.) e Ranidae (1 sp.). To date the PEVA is the area with the third highest number of species in Rio Grande do Sul State.Two species are threatened in Rio Grande do Sul: Haddadus binotatus and Melanophryniscus dorsalis. The main observed threats were: forest drainage, forest fragmentation, presence of invasive species and wetland degradation.

Assessment of the freshwater annual fish Cynopoecilus melanotaenia as a toxicity test organism using three reference substances.

This study presents a preliminary evaluation of the use of the Brazilian fish Cynopoecilus melanotaenia as a test organism in toxicity tests. The cryptobiotic stage presented by the eggs of fish C. melanotaenia can overcome the difficulty of continuously keeping cultures and recruiting healthy animals in sufficient numbers to be used in toxicity tests. In order to determine the applicability of this species as a test organism, three different reference substances were evaluated in 96-h acute toxicity tests: Copper sulfate (CuSO4 x 5H2O), sodium dodecil sulfate (C12H25NaO4S), and sodium chloride (NaCl). Sensitivity ranged as follows: copper sulfate (0.05-0.13 mg/L), sodium dodecil sulfate (10.7-19.0 mg/L), and sodium chloride (1.44-1.96 g/L). We conclude that C. melanotaenia shows potential as a test organism in toxicity tests; however, further research should be conducted with other substances and should be compared with the research on other species before we can reach more conclusive results.

Anura, Bufonidae, Melanophryniscus simplex: Distribution extension.

The genus Melanophryniscus currently includes 20 species distributed in southern Brazil, southern Bolivia, Paraguay, Uruguay, and central and northern Argentina (Di-Bernardo et al. 2006). To date, nine species of Melanophryniscus are known to occur in the state of Rio Grande do Sul, Brazil. Following Caramaschi and Cruz (2002), three species, M. atroluteus, M. dorsalis, and M. montevidensis (see Braun and Braun 1980; Tedros et al. 2001), are included in the Melanophryniscus stelzneri species group; five, M. macrogranulosus, M. cambaraensis, M. tumifrons M. pachyrhynus, and M. devincenzii (see Braun and Braun, 1973; 1979; 1980; Caramaschi and Cruz 2002; Zanella et al. 2007), are in the Melanophryniscus tumifrons group; and M. admirabilis is unassigned to any group (Di-Bernardo et al. 2006).

Vocalization of Hylodes meridionalis (Mertens 1927) (Anura, Hylodidae) in Rio Grande do Sul, Brazil, with comments on nocturnal calling in the family Hylodidae

We describe the advertisement and territorial calls of Hylodes meridionalis for the first time and provide observations on nocturnal calling activity for this species. The advertisement call has 36–82 harmonic notes, with duration of 2.71–5.69 s and dominant frequency on the third harmonic. Advertisement calls are separated by large intervals varying from 18.7 to 44.7 s. The territorial call has 1–3 notes, with duration of 0.039–0.567 seconds, and dominant frequency also on the third harmonic. Territorial calls are emitted at a much higher repetition rate than the advertisement call, with intervals of 1.1–1.6 s between each call. Frogs of the genus Hylodes are known to call mainly during the day, but for H. meridionalis nocturnal calling was observed on various occasions, and could occur regularly until two hours after sunset, or sporadically along the night. Descrevemos os cantos de anúncio e territorial de Hylodes meridionalis pela primeira vez e fornecemos observações sobre a atividade noturna de vocalização para esta espécie. O canto de anúncio tem 36–82 notas harmônicas, com duração de 2,71–5,69 segundos e frequência dominante no terceiro harmônico. Há grandes intervalos entre os cantos de anúncio, de 18,7–44,7 segundos. O canto territorial tem 1–3 notas, com duração de 0,039–0,567 segundos, e frequência dominante também no terceiro harmônico. Cantos territoriais são emitidos a uma taxa de repetição muito mais elevado do que o canto de anúncio, com intervalos de 1,1–1,6 segundos entre cada canto. As espécies do gênero Hylodes são conhecidas por vocalizar principalmente durante o dia, mas machos de H. meridionalis foram observados em atividade de vocalização noturna em várias ocasiões, sendo que podem vocalizar regularmente até duas horas após o pôr do sol, ou esporadicamente ao longo da noite.

Amphibia, Anura, Leptodactylidae, Leptodactylus furnarius : rediscovery and distribution extension in the state of Rio Grande do Sul, Brazil

Leptodactylus furnarius Sazima and Bokermann, 1978 (Figure 1) belongs to the Leptodactylus fuscus species group (Frost 2007), which contains species that build underground chambers to lay eggs in foam nests (Giaretta and Kokubum 2004). Males vocalize on wet ground and shallow water bodies where low and sparse vegetation grows or inside the chambers, near to their foam nests (Achaval and Olmos 2003; Eterovick and Sazima 2004).

Nest site selection by Hypsiboas faber(Anura, Hylidae) in Southern Brazil

Male gladiator frogs of Hypsiboas Wagler, 1830 build nests on available substrate surrounding ponds and streams where female spawn eggs during the breeding period. Although gladiator frogs seem to show plasticity in the way they construct their nests, there is no study reporting if these species present preferences about microhabitat conditions for nest-building (mainly under subtropical climate). Predation pressure and environmental conditions have been considered major processes shaping the great diversity of reproductive strategies performed by amphibians, but microhabitat conditions should explain where to build a nest as well as how nest looks. This study aimed to test nest site selection for nest-building by Hypsiboas faber(Wied-Neuwied, 1821), determining which factors are related to nest site selection and nest features. The survey was conducted at margins of two permanent ponds in Southern Brazil. Habitat factors were evaluated in 18 plots with nest and 18 plots in the surrounding without nest (control), describing vegetation structure and heterogeneity, and substrate characteristics. Water temperature was measured inside the nest and in its adjacency. Nest features assessed were area, depth and temperature. Habitat characteristics differed between plots with and without nest. Microhabitat selected for nest-building was characterized by great vegetation cover and height, as well as shallower water and lower cover of organic matter in suspension than in plots without nest. Differences between temperature inside nest and in its adjacency were not observed. No relationship between nest features and habitat descriptors was evidenced. Results revealed that Hypsiboas faber does not build nests anywhere. Males seem to prefer more protected habitats, probably avoiding predation, invasion of conspecific males and inclement weather. Lack of differences between temperature inside- and outside-nest suggest that nest do not improve this condition for eggs and tadpole development. Nest architecture was not related to habitat characteristics, which may be determined by other factors, as nest checking by females before amplexus. Nest site selection should increase offspring survival as well the breeding success of Hypsiboas faber.