Morphological abnormalities in a blue shark Prionace glauca (Chondrichthyes : Carcharhinidae) foetus from southern Brazil

This study records the occurrence of a blue shark Prionace glauca foetus, with morphological abnormalities in the trunk and cephalic region, from a female caught by a pelagic longline in October 2003, in southern Brazil. (c) 2006 the Authors.

Geochemical Assessment of a Subtropical Reservoir: A Case Study in Curitiba, Southern Brazil

Suspended particles and dissolved substances in water provide reactive surfaces, influence metabolic activity and contribute to the net sediment deposition. It therefore plays an important part in the ecology and quality of the water mass. The water quality in reservoirs is crucial and it is naturally maintained by flushing and sedimentation, which continuously remove phosphorus from the water. In some reservoirs, however, these removal processes are countered by recycling of ions which could play a key role to start and/or maintain the eutrophic state. The combination of macro-, trace- and microanalysis techniques can be useful to trace pollution sources through a chemical fingerprint, whether be during an acute environmental disaster or a long-term release of pollutants. The water quality and total metal content of reservoir sediments were assessed in a reservoir, situated in the capital of the Parana State, in the South-Eastern part of Brazil. The goal of this paper was to determine the metal presence in the sediment and metal and ionic speciation in the Green River reservoir water. Water and bed sediment samples, collected from various sites during 2008 and 2009, were investigated using XRF, ICP-OES, ICP-MS, XRD and zeta potential measurements. Based on the results, the heavy metal concentration and chemical composition of the suspended matter in the water samples, as well as the sediment's chemical composition will be discussed.

The role of spatial and temporal descriptors for neotropical tadpole communities in southern Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fidelity of molluscan assemblages from the touro passo formation (pleistocene-holocene), southern brazil: taphonomy as a tool for discovering natural baselines for freshwater communities

This study is the first assessment of mollusk fossil assemblages relative to the compositional fidelity of modern mollusk living and death assemblages. It also shows that the sedimentary record can provide information on the original, non-human-impacted, freshwater malacofauna biodiversity, based on Late Pleistocene shells. The fossil mollusk assemblage from the Touro Passo Formation (Pleistocene-Holocene) was compared to living and death assemblages of the Touro Passo River, southern Brazil, revealing little resemblance between fossil and live-dead species composition. Although the living and death assemblages agree closely in richness, species composition, and species relative abundances (both proportional and rank), the fossil assemblage differs significantly from both modern assemblages in most of these measures. The fossil assemblage is dominated by the native endemic corbiculid bivalve Cyanocyclas limosa and the gastropod Heleobia aff. bertoniana. These are absent in the living assemblages, and both living and death assemblages are dominated by the alien Asiatic corbiculid C. fluminea, which is absent in the fossil assemblage. The fossil assemblage also contains, overall, a higher proportional abundance of relatively thick-shelled species, suggesting a genuine bias against the thinner- and smaller-shelled species. Our results suggest that contemporary environmental changes, such as the introduction of some alien freshwater mollusk species, together with post-burial taphonomic processes, are the main factors leading to the poor fidelity of the fossil assemblage studied. Hence, the taxonomic composition of the Late Pleistocene mollusks from the Touro Passo Formation probably would show greater similarity to present-day assemblages wherever the mollusk biodiversity is not disturbed by human activities.

Predation on spawn and adults of Chaunus dorbignyi (Dumeril & Bibron, 1841) (Amphibia, Anura) by leeches (Hirudinea) in southern Brazil.

Two species of leeches (Hirudinea) are reported as frequently associated with amphibians in Rio Grande do Sul state, southern Brazil. We observed the predation of eggs of the bufonid Chaunus dorbignyi; remarkably, the remaining eggs of this clutch did not complete their embryologic development, probably due to a negative effect caused by the leeches. We report on additional observations of leeches feeding on other anuran species.

Assessment of effective doses from radon levels for tour guides at several galleries of Santana Cave, Southern Brazil, with CR-39 detectors: preliminary results

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Population biology and reproduction of the hermit crab Clibanarius vittatus (Decapoda: Anomura) in an estuarine region of southern Brazil

The population dynamics and reproduction of the hermit crab Clibanarius vittatus were evaluated on Pescadores Beach, located on the estuarine channel of Sao Vicente (São Paulo), Brazil. The hermit crabs were captured by hand during low tide,from May 2001 to April 2003. A total of 2554 hermit crabs were captured, of which 701 were males, 1741 non-ovigerous females, 48 ovigerous females and 64 intersex individuals. The size-frequency distribution of the males was represented by a platykurtic bell-shaped curve, which differed from the leptokurtic bell-shaped curve of the females. The smaller and intermediate classes were composed mainly of females (modal size 6.5-7.5 mm carapace shield length (CSL)), and the larger classes only by males (modal size 9.5-10.5 mm CSL). The overall sex-ratio was skewed toward females (0.39:1/M:F), differing significantly from the expected 1:1. A seasonal reproductive pattern was recorded for C. vittatus in this location, with more intensive reproductive activity in the warmer months. The absence of juveniles suggests that their recruitment area is different than the area inhabited by adults, possibly another area with more protection and specialized or different resources for young.

Palaeomagnetism of the Mesozoic Serra Geral Formation, southern Brazil

Palaeomagnetic results from 20 volcanic sequences and 11 intrusive bodies (sills and dykes) of the Serra Geral Formation (Paraná Basin) are reported in this paper. The sequences are widespread all over the basin, while sills and dykes (Ponta Grossa arch) come from the northeastern portion. Three mean palaeomagnetic poles were computed for the Serra Geral Formation, which account for a time interval of ∼ 15 Ma. Pole SG1 is located at 85°S,108°E (α95 = 1.1°, N = 18) and represents the main phase of the magmatic activity in the basin, with a mean age of ∼ 135 Ma. Pole SG2 is located at 82°S,38°E (α95 = 7.8°, N = 2) and represents a younger magmatic phase, with an associated age of ∼ 130 Ma. Pole SG3 (72°S,37°E; α95 = 6.8°, N = 10) is the youngest pole. It is computed from the intrusive rocks and its age is assumed to be not younger than 118 Ma, the lower limit of the 'Cretaceous normal magnetic interval'. These three poles describe a shifting path, which suggest that the South American platform moved ∼ 5° southwards and rotated ∼ 10° clockwise during the Lower Cretaceous, preceding the South Atlantic opening. © 1990.

Effects of stocking density on growth of channel catfish, Ictalurus punctatus, fingerlings in Southern Brazil

Channel catfish, Ictalurus punctatus, fingerlings (mean length: 4.0±0.5 cm) were stocked into sixteen 16-m2 tanks with cement walls and earth bottoms. Four stocking densities were used: 10, 15, 20, and 25 fish/m2. Fish were fed a prepared diet containing 36% protein according to a fish size/water temperature-dependant chart for 120 days. Fish were stocked on January 20, 1992. Average water temperature varied from 19.7°C to 28.5°C. Final mean values of individual fish length and weight were significantly higher (P < 0.05) for the density of 10 fish/m2 and averaged 19.4±2.6 cm and 70.0±16.9 g, respectively. Food conversion ratio was significantly higher (P < 0.05) for fish stocked at rate of 25 fish/m2. Survival rates averaged 91.4%, with no significant differences (P > 0.05) found among treatments. These results demonstrate the viability of channel catfish fingerling growth in southern Brazil.

Growth of Channel Catfish, Ictalurus punctatus, in Southern Brazil

Despite successful introduction of channel catfish into Brazil in 1980, no studies have been conducted to assess the performance of channel catfish, Ictalurus punctatus, farming in southern Brazil. Fingerlings (27.0 ± 2.2 g) were stocked in sixteen 16-m2 tanks with cement walls and earthen bottoms. Four stocking densities were used: 0.5, 0.75, 1.0, and 1.25 fish/m2. Fish were fed a diet containing 32% protein according to a feeding chart for 257 days (from April to December). Water temperature ranged from 16.4°C to 30°C during the study. Final average weight (727.1 ± 70.6 g) was significantly higher (P < 0.05) for fish raised at 0.5 fish/m2. Food conversion ratio (FCR) was significantly higher (P < 0.05) for fish stocked at 1.25 fish/ m2. Survival averaged 95.4%, and no significant differences (P > 0.05) were found among treatments. There was no significant difference (P > 0.05) in tank production among the densities of 0.75, 1.0, and 1.25 fish/m2, but they were higher (P < 0.05) than the density of 0.5 fish/ m2. These results demonstrate the viability of channel catfish growth in southern Brazil.

Birds at Eucalyptus and other flowers in Southern Brazil: A review

In southern Brazil, I recorded 14 species of hummingbirds, one woodpecker, three Psittacidae, four Tyrannidae, one mockingbird, and 31 tanagers and relatives at eucalyptus flowers. Others have registered 3 different hummingbirds, another parrotlet, four more tyrannids, a peppershrike, a thrush, and 5 tanagers and related birds, for a total of 69 species. However, commercial plantations rarely flower, so use is local or undependable. Understory Phaethorninae are not recorded at eucalyptus, rarely at other tall and hence multiflowered trees. Bromelias and other flowers are noted in various studies, which add 89 species of flower feeders, including 14 Psittacidae, 17 Trochilidae, and 37 tanagers and relatives. Isolated low flowers and epiphytes are mostly visited by hummingbirds (some by Coereba), but some tall trees (Chorisia) also. As two times as many tanager species visit flowers as hummingbirds, researchers will have to get up early and patiently study treetop and nonpatchy habitats. However, tree plantations can attract artificially, like feeders. Bunch-flowering extrafloral nectar (Mabea, Combretum) is preferred by wandering mixed-flock treetop or edge tanagers and relatives, which often crawl over bunched flowers like parrots or woodpeckers (or marsupials and other mammals) rather than hover at separate flowers like nonflocking Trochilidae or peck from nearby like Nectariniidae and Coereba. Clamberers and petal-pullers, even nectar robbers, can cause evolution of umbels and other bunched flowers, for the bird, mammal or insect receives pollen from nearby flowers. Psittacidae, saltators and others mostly eat flowers, but can pollinate if they touch nearby flowers. Multiflowered trees can also attract hawks, causing waves of tanagers, parrots and others that move on to pollinate trees via fear and nectarivory. Certain groups, notably thrushes and tyrannids, seem to use nectar little, the latter often catching insects.

Holocene paleoclimatic reconstruction based on the Lagoa Dourada deposits, southern Brazil

The Lagoa Dourada is a circular-shaped pond formed on the Furnas Formation (Devonian of the Paraná Basin), filled by late Pleistocene - Holocene sediments. It lies in the hydrographic basin of the Guabiroba River, a tributary of the Tibagi River situated in the Campos Gerais region of the State of Paraná, southern Brazil. The pond is about 200 m in diameter and the maximum water depth is 5.4 m. Geological, chemical, textural and mineralogical studies on a core sample of the sediments collected from the Lagoa Dourada, 12.2 m thick, was obtained for investigations of paleoenvironmental changes as well as to provide additional data to support previous reconstructions based on palynomorphs and diatoms. Within the period recorded in the core, the pond has been filled by sandy material introduced by springs at the northern edge of the pond as well as by muddy material brought in by floodwaters of the Guabiroba River. Thus, the sandy layers could be interpreted as evidence of drier climates with consequent diminution of fluvial overflow, but with maintenance of the sandy deposits coming from springs. The occurrence of euhedral pyrite in the sediments, locally associated with gypsum, may indicate periods of increase in the organic matter content or an increase in the water salinity, what could be related to greater evaporation under drier paleoclimate regimes. Three cycles defined by an increase in the total carbon content of the sediments of the pond were observed. These cycles seem to correspond to an increase in the isotope ratio 13C/12C (δ13C). Several hypotheses can be suggested to explain the presence of these cycles, including the alternation of wetter or drier climatic phases. The convergence of the sedimentological data obtained during this study with previous microfossil paleoclimatic (pollens and diatoms) indicators and radiocarbon dating suggests that a drier paleoclimatic phase occurred around 8720±150 years B.P. The evidence for a second drier phase in more recent times is less consistent. This subsequent phase could correspond to the drier phase in southern and southeastern Brazil between 5000 and 3000 years B.P. as suggested by other paleoclimatic studies.