In this Issue

Abstract

i IN THIS ISSUE Bruce Osborne Solution hollows in the Burren The Burren has, perhaps not surprisingly, figured significantly in Biology and Environment,given its status as one of the more botanically important areas nationally as well as globally (See volume 103B, no.3, for our special issue on the Burren). Whilst previous research has focussed on its botanical diversity and how best to manage the competing interests of farmers and conservationists, less work has been directed at the microbial communities and their significance . It is well known, however, that solution hollows—small depressions in the open limestone pavement that can be filled with rain water—are the sites of a rich microbial community. Cyanobacteria , mainly of the genus Nostoc, often dominate these communities, forming a melange of assorted colonies of various shapes, sizes and colours. However ,there may be a consortium of microbes present including the red chlorophyte Haematococcus pluvialis ; Doddy and Roden, in this issue, show that the solution hollows are the sites of significant primary productivity, presumably aided by the ability of Nostoc to both assimilate atmospheric nitrogen and carbon dioxide. Remarkably too, the Nostoc is extremely resilient and able to survive extended periods of desiccation, as the solution hollows often dry out, with rapid restoration of metabolic activity on re-wetting.Although often surmised,the authors show through in situ experiments that the microbes in the solution hollows are responsible for significant erosion and facilitate the colonization of the limestone pavement by vascular plants. Parental-pup interactions in Harbour Seals The Harbour or Common Seal has a predominantly western distribution in Ireland with few populations on the east coast. Seals when emergent generally occupy rocky ledges and sandbanks or beaches in intertidal coastal habitats.They are often regarded as solitary animals with only a rudimentary social structure but, like so many aquatic animals that spend most of their time in water, this is still open to debate. Adult males do come together during mating and there is a close bonding between mothers and juveniles after birth and early maturation, although mother-pup behaviour has often been poorly documented. Wilson and Jones, in this issue, report on a study of mother-pup interactions in intertidal habitats at Dundrum Bay, in the north east of Ireland. Using visual counts and video footage Wilson and Jones assessed interactions between mothers and their offspring in the water, at the­ water’s edge and at a dry ledge or beach.The majority of mothers gave birth at the beginning of July and pups always remained close to their mothers, although the ratio of pups to mothers varied with habitat. The attachment of young to their parents appeared to be strongest in water, perhaps reflecting the importance of less known social interactions that occur in water that are not routinely observed. Importantly, Wilson and Jones argue that a better understanding of social interactions between pup and mother will be important for the rehabilitation of orphan seals in captivity, prior to their release. Harbour seal pups can become separated from their mothers after birth and the care of these stranded pups needs to account for the social behaviour that they would normally experience in nature through, for instance, the use of companion pups and access to shallow water pools.Together with information obtained from comparisons of the behaviour of orphans in captivity with that observed in the field this could significantly improve the success of rehabilitation and re-introduction programmes. Are they there or are they not? An ability to accurately document changes in species numbers or abundance has become a crucial factor in ascribing any alterations to climate change or other anthropogenic factors.This is,however,not as easy as it seems. Often our assessments of change are dependent on historical data of uncertain quality in regard to their temporal and spatial coverage, or because of the failure to identify species correctly , or because of inter-annual climate variations. A further complication in aquatic habitats is that the presence or absence of a species may also depend on recruitment patterns. Even well-studied areas cannot escape these issues it seems.The Lough Hyne Marine Reserve in Co. Cork is an intensively studied...