Bruno Sant'Anna - Academia.edu (original) (raw)

Papers by Bruno Sant'Anna

The number of investigations has increased worldwide about the abundance and distribution of micr... more The number of investigations has increased worldwide about the abundance and distribution of microplastics in different water bodies and biota. This study investigated microplastic contamination in bathhouses in the Middle Amazon, in Itacoatiara, AM, Brazil. A total of 202 microplastic particles were recorded in the five investigated areas used for recreation. These results indicate no significant difference in the number of microplastic particles between bathhouses (KW = 7.4805; P = 0.1126). The size of the microplastic particles differed significantly between the bathhouses (KW = 40.9582; P = 0.0001). Both blue and red microplastic particles were recorded, with blue particles being the most abundant. The microplastic particles were in the form of fibers and fragments. The number of microplastic particles (U = 7.4686; P = 0.0001) was significantly different between the areas within and adjacent to the bathhouses; however, the size of microplastic particles were not significantly di...

Acta Amazonica

Few studies in the Amazon region have evaluated anuran diversity in urban forest fragments or in ... more Few studies in the Amazon region have evaluated anuran diversity in urban forest fragments or in areas with differing degrees of anthropogenic impact. We determined the composition and abundance of the anurofauna in urban and rural sites within the municipality of Itacoatiara in central Amazonia, Brazil. Specimens were sampled from January 2012 to May 2013 in 10 urban sites and five rural sites. A total of 1,538 anurans (930 in rural sites and 608 in urban sites) were recorded, belonging to 29 species in five families. Species richness was higher in rural sites, with 10 exclusive species. All species found in urban sites were also found in rural sites, however, species abundance varied considerably between the habitats. Sampling- and individual-based rarefaction curves showed a tendency toward stabilization of species richness only in the urban sites. We concluded that the anuran assemblages in the urban sites are depauperate due to the absence of many species associated to pristine...

The species of the genus Pennella are highly modified copepods that have been found parasitizing ... more The species of the genus Pennella are highly modified copepods that have been found parasitizing several species of fishes in Atlantic waters. Although these parasites have been recorded several times in the Atlantic Ocean, little is known about them in South Atlantic waters, except for one report published 20 years ago. The present contribution reports the occurrence of Pennella instructa Wilson, 1917 parasitizing the swordfish Xiphias gladius Linnaeus, 1758 in the South Atlantic. The prevalence of infestation was 15.6% and the mean intensity of infestation was 1.6, ranging from 1 to 3.

Latin American Journal of Aquatic Research

Crabs use burrows to prevent predation, environmental interference and shelter. The present study... more Crabs use burrows to prevent predation, environmental interference and shelter. The present study investigated the excavation behavior of the trichodactylid crab Dilocarcinus pagei, considering the biometric aspects of the burrows, the excavation time, the amount of bioturbation and the excavation behavior of the two sexes. The burrows of males had a mean diameter larger than the females, although the depth was similar for both sexes. Females had higher bioturbation than males, and showed enlargement in a camera format at the bottom, even closing the entrance of the burrows with a "plug" after their construction. Both the camera and the presence of the "plug" in the burrows of the females may be associated with reproduction. The presence of pellets observed at the entrance of burrows is associated with the cleaning of the pereiopods by crabs after the excavation. The sequence of behaviors for the construction of the burrows is described in detail, contributing to...

Marine and Freshwater Research

This study investigated the predation of eggs of the apple snail Pomacea dolioides in Itacoatiara... more This study investigated the predation of eggs of the apple snail Pomacea dolioides in Itacoatiara, Amazonas, Brazil. Predation was compared between rural and urban areas, period of day, shaded and unshaded clutches. In addition, we evaluated clutch height and the behaviour of predators. Between April 2017 and July 2018, 962 egg clutches were observed at different times of the day: 492 in rural areas with predation of 68 egg clutches and 470 in urban areas with predation of only 9 egg clutches. Significant differences were recorded for predation rate and differences were recorded for egg clutch height in the areas. In the rural areas, the most frequent predators during the day were ants Solenopsis invicta, Crematogaster cf. carinata and the most abundant were S. invicta, Wasmannia aff. iheringi and C. cf. carinata. During the night, S. invicta was the most frequent and abundant predator. In urban areas, the frequency of predation and abundance of S. invicta were higher during the day...

Revista Brasileira de Zootecnia

Scientific reports, Jan 11, 2018

Obtaining accurate and reproducible estimates of internal shell volume is a vital requirement for... more Obtaining accurate and reproducible estimates of internal shell volume is a vital requirement for studies into the ecology of a range of shell-occupying organisms, including hermit crabs. Shell internal volume is usually estimated by filling the shell cavity with water or sand, however, there has been no systematic assessment of the reliability of these methods and moreover no comparison with modern alternatives, e.g., computed tomography (CT). This study undertakes the first assessment of the measurement reproducibility of three contrasting approaches across a spectrum of shell architectures and sizes. While our results suggested a certain level of variability inherent for all methods, we conclude that a single measure using sand/water is likely to be sufficient for the majority of studies. However, care must be taken as precision may decline with increasing shell size and structural complexity. CT provided less variation between repeat measures but volume estimates were consistent...

Marine Biology Research, 2016

El objetivo de este estudio fue definir la distribución de tres especies de cangrejo ermitaño y l... more El objetivo de este estudio fue definir la distribución de tres especies de cangrejo ermitaño y la utilización de conchas en el sublitoral no consolidado del complejo bahía-estuario de São Vicente, Provincia de São Paulo, en Brasil. Las muestras fueron retiradas mensualmente durante dos años consecutivos. Factores ambientales como temperatura, salinidad y profundidad, también fueron registrados todos los meses. Las tres especies de ermitaños Clibanarius vittatus, Loxopagurus loxochelis e Isocheles sawayai fueron capturadas con la utilización de la concha de seis especies de gasterópodos; 92,7% de los individuos utilizaron conchas de Stramonita haemastoma. Los resultados indicaron una fuerte asociación entre la distribución espacial de los ermitaños y la salinidad, que mostró ser el principal factor límite de su distribución en ese estuario. I. sawayai fue la única especie presente en todos los lugares muestreados en este estudio; C. vittatus fue capturado solamente en los lugares de...

Marine Biology Research, 2015

The Biological bulletin, 2014

To understand sperm plug dissolution and spermatophore dehiscence in Portunidae, histological and... more To understand sperm plug dissolution and spermatophore dehiscence in Portunidae, histological and ultrastructural changes in the seminal receptacle (SR) of Arenaeus cribrarius were investigated during ovarian development. In juvenile females the SR was filled with acid polysaccharides and the dorsal epithelium was stratified. Mated females with rudimentary ovaries showed a large SR filled by a glycoprotein sperm plug. This plug was present until the developing-ovary stage, when spermatophore dehiscence and intense holocrine secretions in the dorsal dense layer occurred. The plug was absent after the intermediate stage, and the SR became flaccid. The secretion produced moved the spermatophores into the ventral region. The modified dorsal epithelium in the transition between the dorsal and ventral regions released acid polysaccharides, which were found among the sperm, by exocytosis. The morphological changes of the SR in A. cribrarius, including the presence of the sperm plug, follow...

Anais da Academia Brasileira de Ciências, 2015

A marine biological invasion is a natural process accelerated by human activities, and the crab C... more A marine biological invasion is a natural process accelerated by human activities, and the crab Charybdis hellerii is an example of a globally widespread invasive species. This study evaluated color variation in C. hellerii and its relationship to the sex, size and sexual maturity of these crabs, and compared the efficiency of a freeware digital image-editing program with a commercially available program. The color of the individuals was analyzed using standardized digital images. The color pattern varied significantly with size; smaller and immature individuals were darker than larger and mature ones. The female abdomen changed in morphology and color with sexual maturity, becoming wider and orange-colored. There was no statistical difference in the color values between males and females and immature males did not show morphological or color differences in their abdomen. This study highlights the possible relationships of the color and physiological state of the reproductive system...

Marine and Freshwater Research, 2015

This study investigated the behaviour of Pomacea bridgesii, describing the daily activity, substr... more This study investigated the behaviour of Pomacea bridgesii, describing the daily activity, substrate selection and the influence of the flood regime in the Amazon, the species’ native habitat. The present study described the daily activity and substrate selection, and evaluated the activity adaptations of the gastropods in a simulated flood-pulse regime. Gastropods were collected in Amazonas, Brazil, in June 2013. Assessments of the daily behaviour, substrate selection, and flood-pulse simulation were made in experimental water tanks. The snails were observed hourly for 48h, and their behaviour recorded on an ethogram. The snails were more active during the night, when up to 80% of them moved about. In general, during both day and night, the gastropods used the pebble substrate most often. Comparing the day periods, a significant proportion of the individuals that were using the pebbles moved to other substrates (t=5; d.f.=2; P=0.03). The interaction of the behaviour of P. bridgesii...

Zoologia (Curitiba), 2014

Investigaciones marinas, 2005

Anais da Academia Brasileira de Ciências, 2014

The mangrove crab Ucides cordatus is one of the most exploited crustaceans in Brazil. The present... more The mangrove crab Ucides cordatus is one of the most exploited crustaceans in Brazil. The present study investigated the breeding season of this species and the period of the "andada" phenomenon, when the crabs are active outside their burrows and perform agonistic behaviors. Furthermore related them to environmental factors, in a mangrove on the coast of Brazil, with inferences about management of this crab. The crabs reproduced from October through February. The "andada" occurred from November through February, with typical characteristics in the first two months, during the full and new moon periods, and was influenced positively by the air and soil temperature, luminosity, and tidal amplitude, and negatively by salinity. Based on the results of the present study, the period when the "andada" occurs in other parts of Brazil could be defined, which will aid in managing this fishery. For Iguape, state of São Paulo, Brazil, we suggest a legal off-season...

Open Journal of Ecology, 2013