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Benthic surveys of Borge Bay, Signy Island, South Orkney Islands indicated that the biomass of macrophytes per area, in shallow; antarctic waters, was less than in temperate seas. This decrease was mainly attributed to the shading and mechanical attrition of sea ice. The habitat provided by macroalgae was important as a source of food and shelter to a wide variety of benthic and demersal species. Feeding relationships within the habitat were complex. Many species relied heavily on phytoplankton or detritus (often phytoplankton 'fall-out') as the main source of food. The biology of two contrasting invertebrates, commonly associated with the fronds of the brown alga Desmarestia anceps was investigated. The species chosen were the amphipod Pontogeneia antarctica and the bivalve Lissarca miliaris. The mollusc remained in the benthos throughout the year, whilst the crustacean exhibited a major migration to the under surf ace of the fast ice during the winter. Despite such obvious ecological differences, some fundamental similarities were apparent in the reproductive biology of these animals. In addition, the growth rates of both species were relatively slow. Studies on metabolism and feeding of P.antarctica indicated that the rate of respiration was higher than expected for the constant low ambient temperature. It is considered that the phenomena of slow growth, increased parentalism and decreased fecundity present in these, and many polar species, can be partly attributed to such elevated metabolism and to the highly fluctuating primary production of antarctic waters which subsequently affects the overall amounts of energy which can be ingested during the year. Breeding in both animals was synchronised to the period of optimum food supply during early spring or summer.

The study concerned distribution, habitat use, diet and the age of roe deer (Capreolus capreolus) from Hamsterley Forest, Co. Durham. Observation and counts of pellet groups indicated that the most used habitats were rides and clearings. Within each habitat the distribution of pellet groups were random, and in general not correlated with indices of plant type and cover density. Over the study area as a whole, the distribution of pellet groups was clumped, and generally correlated with these indices. The mean territory size of territorial bucks was 11.2 ha, the same as mean home range size of non-territorial bucks. Mean home range size of does was 8.0 ha. In 1973 and 16.5 ha. In 1974. The diet was studied by rumen contents and faecal analysis and a comparison of the dried weights of vegetation clipped from inside and outside enclosures. The first two methods indicated that dwarf shrubs were the most used plant group with Calluna the most important food. The third of these methods suggested that grazing pressure was light and at the sampling intensity used was unreliable for indicating diet. Faecal analysis indicated that in winter sheep (Ovis Aries) ate significantly more grasses and grass like plants and less browse than the deer. The eruption and wear method of estimating age was generally accurate to within one year, given knowledge of the life span of the deer. The cementum layer method appeared to be completely reliable; layering was of greater clarity in histological than in gross sections of cementum. The dry weight of the eye lens increased rapidly up to 12 months of age and then slowly up to five years. Body weight increased up to about 18 months of age but not subsequently.

Theoretical studies of the resilience of ecological systems to environmental change predict that the size distributions of species in ecosystems should have discontinuities that reflect similar discontinuities in ecosystem processes. Body size distributions should have many peaks and troughs (modes) for natural, undisturbed ecosystems, but that as disturbances increases, so the number of modes declines. If so, this prediction has implications for assessing the quality of real ecological systems and has potential for environmental monitoring. This research was carried out to explore the relationship between water quality and body size patterns in benthic communities in order to establish the potential of size based indicators for assessing environmental condition, as well as testing Holling's (1992) proposition that lumpiness occurs in body size distributions across a broad range of spatial and temporal scales. The invertebrate samples were collected from both lentic and lotic habitats including rivers, ponds and canals in Yorkshire, UK, known to experience different degree of pollution. Five stations on the River Ure system and nine sites on the River Aire were sampled for moving water while eight stations were sampled for static (canals and ponds) habitats in the area South East of York. Community Abundance, BMWP score, water conductivity and ASPT analysis confirmed varying water quality among these sites. Visual observation of body mass pattern showed skewed distributions towards smaller size classes and most had two very obvious modes at medium and large size classes except for the most polluted habitats. Similarly, statistically rigorous estimates using Kernel Density Analysis (KDE) revealed highly significant relationships between the number of modes and water quality for running water. However, this study was unable to firmly relate discontinuities in body mass distributions to water quality in static water bodies and in fact the relationship appear to be the opposite of those found for moving water. Analysis of the number of gaps, using Holling's (1992) Body Mass Difference Index (BMDI), revealed wide variation in clean and intermediate water quality sites, though the most polluted site had the fewest gaps. However, other disturbed sites had more gaps and some clean sites had fewer gaps. It is clear that size distributions in benthic communities are lumpy, in the sense that most sites showed more than one mode or many gaps, but the number of gaps (discontinuities) is not always correlated with disturbance, at least for the water quality of freshwater systems.