Nest-site selection by roseate terns breeding on aride island, Seychelles

Nest-site selection by tropical Roseate Terns (Sterna dougallii) was examined on Aride Island, Seychelles. Continuous variables reflecting concealment of the nest site, shelter, vegetation cover and intraspecific nest density were measured for nest-sites and random points. Seasonal variation in the initiation of nests with overhangs and their influence on hatching success and adult intraspecific aggression towards chicks were also examined. Roseate Terns selected nest-sites closer to taller vertical objects, and with a higher percentage of rocks, logs or branches overhanging the nest than occurred at random points. Nest-sites in small colonies differed more from the available habitat than did those in the main colony. Nesting density was positively correlated with the amount of rock cover. On Aride and other colonies in the tropics Roseate Terns breed at higher densities than their temperate counter-parts and spacing between neighbors may be a main factor in the selection of nest-sites, especially for birds nesting at the peak of the breeding season. Nest-site characteristics, notably overhangs, had no influence on hatching success. However, the proportion of chicks that died from adult pecking was significantly lower in nests with overhangs. Concealment is a main factor of Roseate Tern nest-site selection throughout its breeding range, in both tropical and temperate areas, but the factors selecting for concealment seem to vary amongst colonies. On Aride concealment appeared to be advantageous in defending territories and protecting young chicks from attacks of adults. Artificial overhangs could be provided to enhance chick survival

Seasonal variation in reproductive measures of tropical Roseate Terns Sterna dougallii: previously undescribed breeding patterns in a seabird

Seasonal variation in egg-laying, egg size, hatching success, hatchling mass, fledging success and chick growth of Roseate Terns Sterna dougallii breeding on Aride Island (Seychelles), Indian Ocean, were studied in 1997 and 1998. I investigated to what extent two patterns, common in a range of species, were followed by tropical Roseate Terns: (a) seasonal decrease in clutch size, egg size and breeding success and (b) an increase in breeding success with increasing egg weight. In 1997 (a poor year), the earliest nesting birds laid significantly smaller eggs, and chicks were lighter at hatching than those of peak nesting birds. The mean clutch size, of 1.04 eggs, showed no seasonal variation and no 'b'-eggs hatched. In 1998 (a good year) the earliest nesting birds laid eggs of similar size and their chicks were of similar weight to those of peak nesting birds. Mean clutch size, of 1.2 5 eggs, increased significantly through the season and about 60% of the 'b'-eggs hatched. In 1997, hatching success was 57% whereas in 1998 it was 80%. In both years, breeding success declined significantly through the season. The fact that the earliest breeding birds laid smaller eggs in a poor year and smaller clutches in a good year is in marked contrast to a range of other species, and to temperate-nesting Roseate Terns. Egg volume explained about half of the variance in hatchling mass in both years, but only 15% of the variation in linear growth rate. Hatching date was the only variable with a significant effect on fledging success. Roseate Terns on Aride seemed to sacrifice egg size and clutch size for earliness of laying. Presumably it is a strategy of older birds to lay as early as possible and may be regarded as a response of tropical Roseate Terns to breeding under relatively poor, and seasonally declining, food conditions

Estado crítico de la investigación en la psicología ecuatoriana: el abandono de la estadística como base de la producción científica

This article reports a study that analyzed the role of statistics in the scientific production of Ecuadorian psychology based on a mixed methodology study. The sample included 410 participants (students and professionals of different cities of Ecuador). The findings on the quantitative phase included that liking and mastering statistical processes increase the probability of publishing a scientific article. Moreover, when negative belief variables and anxiety related to statistics have a higher score, the mastery of statistical processes and its use for the job of the psychologist decrease. On the qualitative phase, a significance emerged that allowed to better understand quantitative data, and to develop categories on statistics erroneous' believes, procedures, a negative predisposition towards learning statistics and others. The paper concludes by analyzing the scientific reality of Ecuadorian psychology and the need to carry out longitudinal research where it will be possible to restructure subjective constructions on the role of statistics in psychology

Ciclo anual do Priôlo Açoreano Pyrrhula murina Goldman, 1866 (Aves: Passeriformes)

Descreve-se o ciclo anual do Priôlo, Pyrrhula murina. Esta ave nidifica de Junho a Agosto, quando a abundância de alimento é elevada, e começa a muda de penas em Setembro. O peso e o Índice de gordura apresentaram variações sazonais reduzidas. A mortalidade anual é provavelmente menos de 60%. O grupo de aves observadas em cada mês apresentou sempre uma mediana de um ou dois. De um modo geral, o Priôlo apresenta um padrão sazonal semelhante ao de outros Pyrrhula da Europa Ocidental, embora com ligeiras variações. Tal facto deverá estar relacionado com o clima temperado oceânico de S. Miguel.ABSTRACT: The annual cycle of the Azores bullfinch or Priôlo, Pyrrhula murina, is described. This bird breeds from June to August, when food abundance is high, and starts moulting in September. Seasonal variations in body weight and fat scores were small. The annual mortality is probably less than 60%. The median monthly group size was always one or two. Overall, it presents a strong seasonal pattern similar to that of western European Pyrrhula, but with slight variations. These should be an environmental correlate of the oceanic temperate climate of S. Miguel Island

Oliva, Salvador: La métrica i el ritme de la prosa.

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