Population Monitoring of the Coelacanth (Latimeria chalumnae)

In 1991 the population size of the coelacanth (   Latimeria chalumnae ) on Grande Comore Island, Western Indian Ocean, was estimated at 230–650 individuals, based on counts of individually recognized fish in an 8-km stretch of coastline. This census area represents about 9% of the total suitable habitat at the island. Counts in the same area in 1994 indicated a reduction of sighted coelacanths of about 30%. Additional surveys in 1995 suggested a total coelacanth population of less than 300 individuals. The local artisanal fishery is probably responsible for the observed decline. The survival of the coelacanth seems to be severely threatened if fishing pressure is not reduced. Conservation measures should focus on providing local fishermen with fishing alternatives.

Monitoreo Poblacional del Celacanto ( Latimeria chalumnae )

En 1991 el tamaño poblacional del celacanto, Latimeria chalumnae en Grande Comore, al Oeste del Oceano Indico, fue estimada de 230 a 650 individuos, en base a conteos de individuos reconocidos en un estrecho costero de 8 km de longitud. Esta área de censo representa cerca de un 9% del total de hábitat adecuado en la isla. Los conteos en la zona en 1994 indicaron una reducción de celacantos de aproximadamnete un 30%. Estudios adicionales en 1995 sugirieron una población total de menos de 300 individuos. Probablemente la pesqueria artesanal local es responsable de la declinación observada. La sobrevivencia del celacanto aparenta estar amenazada si la presion por pesca no disminuye. Las medidas de conservación se deberan enfocar en proveer a los pescadores locales de alternataivas de pesca.     

Storm surges: perspectives and options

This review paper attempts to summarize the scattered and fragmented knowledge about past and possible future changing storm-surge statistics using the particularly well-studied case of the North Sea as an example. For this region, a complete and robust analysis methodology has been developed in recent years. This methodology is based on dynamical and statistical models. Using the concept of dynamical downscaling, development during recent decades, when sufficiently good and homogeneous weather data exist, has been “reconstructed,” and scenarios of possible future change are described. “Localization” allows estimation of changes at specific sites, e.g., harbors. As local water-level statistics depend not only on climate variations but also on local modifications of the local bathymetry, new options for adaptation emerge. For the case of Hamburg, an option for such future adaptations is discussed.     

Environmental education for engineers: An Australian viewpoint

Summary Australian engineering undergraduate courses of 1987 are described as being devoid of any real environmental content. It is suggested that this is an important omission, for engineers should have a duty to consider the environmental impact of their works. Possible ways in which an environmental component could be added to existing engineering courses are outlined.Prepared by the Environmental Education Subcommittee of the Environmental Engineering Panel of the Sydney Division of the Institution of Engineers, AustraliaHans Bandler is a member of the Environmental Engineering Panel of the Sydney Division of the Institution of Engineers, Australia and its Environmental Education Subcommittee. This paper was prepared and distributed as a Discussion Paper on Environmental Education for Engineering Undergraduates in April, 1987. Preparation of the paper was assisted by a draft document from the Institution of Engineers, Australia's National Committee on Environmental Engineering.     

Feeding frequency and parental division of labour in the double-brooded great tit Parus major

Summary We studied the relative contribution of each sex and total effort expended in feeding nestlings in the great tit Parus major in relation to artificially altered brood size. A recent model suggests that feeding frequency should reflect the optimal trade-off between parental and fledgling survival, the former being negatively, the latter positively, influenced by high feeding frequencies. In both sexes weight loss was linearly related to feeding frequency. Since fledgling survival increases with nestling weight, the conditions of this model are fulfilled. However, in contrast to the predictions of the model, the total feeding frequency for both sexes combined did not differ between control and enlarged broods, but was lower for reduced ones. This outcome was not the result of a physiologically related inability of the parents to increase their delivery rate. Instead, we suggest that parents with enlarged broods could not find sufficient amounts of prey large enough to be economically worth transporting to the nest. Differences in brood-provisioning rates between the sexes may arise because costs and benefits of feeding nestlings may differ. Females lost more weight than males during the nesting period, but maintained a relatively higher weight during the incubation period. The relationship between weight loss and feeding frequency was similar for both sexes. Male and female brood-feeding frequency was related to brood size in a similar way. This is discussed in light of the great tit's mating system and the fact that the great tit is facultatively double-brooded.