Temporal, diel and spatial variability of decapod larvae from St Paul`s Rocks, an equatorial oceanic island of Brazil

Temporal, spatial and diel variation in the distribution and abundance of organisms is an inherent property of ecological systems. The present study describes these variations and the composition of decapod larvae from the surface waters of St Paul`s Rocks. The expeditions to the archipelago were carried out in April, August and November 2003, March 2004 and May 2005. Surface plankton samples were collected during the morning and dusk periods, inside the inlet and in increasing distances around the archipelago (similar to 150, 700 and 1500 m). The identification resulted in 51 taxa. Seven species, six genera and larvae of the families Pandalidae and Portunidae were identified for the first time in the area. The mean larval density varied from zero to 150.2 +/- 69.6 individuals 100 m(-3) in the waters surrounding the archipelago and from 1.7 +/- 3.0 to 12,827 +/- 15,073 individuals 100 m(-3) inside the inlet. Significant differences on larval density were verified between months and period of the day, but not among the three sites around the archipelago. Cluster and non-metric multidimensional scaling analysis indicated that the decapod larvae community was divided into benthic and pelagic assemblages. Indicator species analysis (ISA) showed that six Brachyura taxa were good indicators for the inlet, while three sergestids were the main species from the waters around the archipelago. These results suggest that St Paul`s Rocks can be divided into two habitats, based on larval composition, density and diversity values: the inlet and the waters surrounding the archipelago.

JUVENILE RECRUITMENT, EARLY GROWTH, AND MORPHOLOGICAL VARIATION IN THE ENDANGERED SANTA CATALINA ISLAND RATTLESNAKE, CROTALUS CATALINENSIS

Life-history information constitutes the raw data for building population models used in species conservation. We provide life-history data for the endangered Santa Catalina Island Rattlesnake, Crotalus catalinensis. We use data from 277 observations of C. catalinensis made between 2002 and 2011 on the island. Mean snout-vent length (SVL) of adult C. catalinensis was 643 mm for males and 631 mm for females; the difference was not significant. The degree of sexual size dimorphism (SSD; using SVL) was -0.02. However, sexes were dimorphic in total length ( SVL + tail length), relative tail length, and stoutness. Juvenile recruitment occurs during late-summer. In their first year of life, juveniles seem to grow at a rate of about 1.7 cm/mo. Females seem to become mature around 570 mm SVL, probably in the year when they become 2 y old. Scattered literature data corroborates the time of juvenile recruitment described herein. Growth in C. catalinensis seems to be slower than that of C. ruber, its sister taxa, but similar to other rattlesnakes.

On the existence of G-equivariant maps

Let G be a compact Lie group. Let X, Y be free G-spaces. In this paper, by using the numerical index i (X; R), under cohomological conditions on the spaces X and Y, we consider the question of the existence of G-equivariant maps f: X -> Y.

Heat island simulations in Londrina city, Brazil

This work aims to study the urban heat island on North region of Parana state, Brazil and the influence of land use and urban settlements on the intensity and frequency of occurrence of these events. Through atmospheric modeling whith WRF/Chem model two simulations were made with different land and use files, one with the original land use another obtained from a composition of MODIS-Landsat imagery. The simulations showed good skills compared to observed data. Urban areas presented higher temperatures. Landsat land use has represented better urban heat islands (UHI), the gradient between urban and rural areas was well demonstrated and the correlation coefficient was above 0.92. The model underestimated the maximum values and overestimated the minimum compared with observed data in both simulations.