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Edinburgh has 20-35 breeding pairs of Sparrowhawks. Their ecology is similar to those living in rural areas (See: Newton 1986). House Sparows were the most important Sparrowhawk prey: 27% of prey items, and 22% of biomass. Sparrowhawks fed on whatever prey, within a certain size range, was available. The mean nearest-neighbour distance was 1.3 ± 0.08 km. There was no indication that the composition of the population differed from that found in the rural areas. Adult female survival was 53%, yearling survival 41%. Pollutants were not particularly high. The average residency for a breeding female Sparrowhawk was 1.4 yrs, and 1.5 yrs for the male. 54% of all trapped females were new recruits to the breeding population. Range sizes varied with season, age and sex of individuals. The mean range size for breeding, adult males was about 400 ha. Range size could be affected by roosting behaviour. Some birds breeders roosted up to 2 km away from their nesting place. Range size of yearlings was directly related to the number of roost sites used, which increased as egg-date approaches. This was interpreted as prospecting for openings in the breeding population. 51 potential nesting places were identified, 39 were occupied in the 4 years. Some nesting places were preferred. On average, 24 nests produced eggs/yr, 3.94 eggs/nest were laid, 2.47 chicks hatched/nest, and 2.3 fledged/nest. Wet, cold weather in spring and summer decreased production. Production was affected by the turnover of breeding females. Other causes of variation, including human disturbance, could not be proven. The breeding behaviours of Sparrowhawks were observed and interpreted in terms of the possible reproductive strategies of the individuals. Breeding male and female Sparrowhawks spent more time at the nesting place as egg-date approached, and more time together in the morning and late afternoon. Mate guarding could not be proven. Displays increased as egg-date approached, and were more common in the morning. Courtship feeding increased as egg-date approached. Food presentations by the male were mostly made in the morning. Copulations showed similar seasonal and diurnal variation to the other behaviours. Copulation rates were high (150-0250/clutch). There was no concrete evidence that the male was buying copulations with food presentations. All behavioural rates were affected by breeding birds roosting at the nesting place together later in the season. 13% of all copulations were extra-pair, and occurred when an intruding female (which was paired with another male) solicited a territory holding male. Sperm storage tubules were identified in the reproductive tract of female Sparrowhawks. Chicks were produced which were not the offspring of the male with which the female was 'paired'.

A survey was carried out on the overall langur population size in Bapen Reserve. Data showed that local extinction has been occurring for a long time, due to habitat destruction and hunting. However, a drastic population decline has taken place over the past ten years. Most langurs were found in a hill-group in which the Reserve staff members often patrol. This hill-group was defined as the main langur population pool of the Reserve. Further detailed sampling in this area showed a much higher population density compared to other hill-groups. Langurs preferred large areas of continuous habitat. A similar survey was carried out in Longgang Reserve, Ningming County, which indicated a high population density in the central area of that reserve where the habitat has been much less disturbed by humans. In the main population pool, data were collected on climate, distribution of vegetation patches, plant species richness, phenology of food plant species, feeding ecology, range use and group dynamics. Habitat quality was classified according to the extent of human disturbance. Results showed that a large amount of mature leaves was available year round. Young leaves maintained a low level of availability, but disappeared almost completely in the winter of 1997. Rainfall was seasonal and was linked to the production of fruits and young leaves. Vegetation was mainly distributed on the lowest 40% of the hills. Behavioural data showed that the activity of white-headed langurs was restricted on the hills by the distribution of vegetation. Langurs fed mostly on rare plant species. These were more likely to occur in higher quality habitat, for which different langur groups competed. As a consequence, only the langur groups living in 50% of the higher quality habitat area produced offspring. Langurs fed intensively on young leaves. Compared to other colobine species, white-headed langurs were extremely folivorous. This seemed to be related to their smaller area of range use.

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Grasshoppers and bush-crickets, collectively known as Orthoptera, are a critical invertebrate prey group for a number of declining farmland birds, including the cirl bunting (Emberiza cirlus). This study focuses on one species of Orthoptera, the meadow grasshopper (Chorthippus parallelus). The key objective was to provide an evidence base in order to identify the agri-environment scheme prescriptions and management practices of greatest value to C. parallelus. This information will help formulate management recommendations that will enhance C. parallelus abundance in agro-ecosystems, which in turn will contribute to the conservation of farmland birds. Comparisons between agri-environment pasture, 2m and 6m arable margins, longterm set-aside and intensively grazed pasture revealed that 6m margins and longterm set-aside tended to support significantly higher densities of adult C. paralle/us. The abundance of nymphs, however, did not appear to differ between the habitats surveyed. The abundance of C. parallelus adults and nymphs was influenced by a combination of sward architecture and botanical composition. Sward height was particularly important. Early stage nymphs preferred short swards, and as individuals matured sward height preferences shifted towards taller swards. Sward heights on agrienvironment pastures appear to be too short to benefit adult C. parallelus, whilst swards on arable margins are too tall to benefit nymphs. Mowing in July significantly reduced the abundance of C. parallelus adults and late stage nymphs, whereas mowing in May appeared to benefit early stage nymphs. The most critical and simplest improvement on current management practices would be to delay the mowing of grasslands and arable margins, which commonly occurs in July or August, until later in the season. It is proposed here that mowing should not be undertaken before September. Furthermore, results suggest that grazing on agrienvironment pastures should be lighter if higher abundances of C. parallelus are required to benefit farmland bird populations.

The black-kneed capsid bug, Blepharidopterus angulatus(Fallen) is an important colonizer of orchards in late summer. Capsids develop on alder windbreaks feeding on the aphid Pterocallis alni(Degeer). When the aphid population declines adult bugs move to nearby orchards where they feed on pest species. The biology and ecology of P. alni has been examined in order that predator populations may be manipulated. Aphid populations increase rapidly to a peak, then suddenly decline. A high initial population results in a peak in mid July, low initial numbers result in a peak in early August. Pruning of the windbreaks can alter the population cycles of the aphid. P. alni is polymorphic and crowding results in the production of winged individuals. The crowding stimulus acts pre and post natally. Flight is stimulated by crowding and emigrating alatae colonize other alder trees. Sexual forms of the aphid are produced as a response to a shortening of the daylength in autumn. In field conditions adult aphids produce a reproductive sequence of virginoparae, males and finally oviparae. Egg laying and distribution were examined and winter mortality monitored. Arthropod predators are the main cause of egg loss and greatest mortality occurs in early winter. The food quality of alder leaves for the aphids deteriorates in early summer. Poorer food, rising temperatures and increased crowding result in smaller aphids which are less fecund. Recruitment to the population falls and numbers collapse when emigration exceeds recruitment. The emigration of B. angulatus from alder is closely synchronized with the abundance of P. alni. The key mortality factor in bug populations is theloss of reproductive females. However, female capsids tend to remain on the windbreak unless their prey disappears completely. If this occurs, both sexes will migrate to the orchard. Capsid numbers and movements are indirectly affected by cultural practices of the alder resulting-in changes in aphid abundance

I examine the niche partitioning between native ring-tailed lemurs, Lemur catta, and an introduced hybrid brown lemur population of Eulemur rufus x E. collaris in Malaza gallery forest of Berenty reserve, in comparison with the natural sympatric population of ring-tailed lemurs and red collared brown lemurs, Eulemur collaris, in Ambatotsirongorongo forest and with allopatric ring-tailed lemurs at Bealoka forest, in order to determine the impact of the introduced brown lemur population at Berenty reserve on the behaviour and distribution of native ring-tailed lemurs. Behavioural observations were conducted from September 2008 to December 2009; lemur population survey was conducted from 2005 to 2009. Behavioural sampling methods include scan group sampling, focal animal sampling and ad libitum of social behaviour and feeding behaviour. Two groups of each lemur species were followed in Malaza Berenty forest, one group of ring-tailed lemurs in Bealoka forest and one group of each lemur species was followed in Ambatotsirongorongo forest. Vegetation study was conducted in Bealoka and Berenty forests, whereas preliminary data on vegetation structure was already available for Ambatotsirongorongo. At Berenty reserve, the dynamic of the native ring-tailed lemur population was conditioned by food availability and habitat quality. The brown lemur growth and distribution appear to be affected by the water availability. Individual energy demands for various activity rhythms play a big role in brown lemurs' ecology. Food availability, hierarchy and territory are the main niche dimensions that shape ring-tailed lemurs' ecology. Niche partitioning between native population of ring-tailed and collared brown lemurs at Ambatotsirongorongo forest relies mainly on habitat use. Feeding ecology of ringtailed lemurs in Bealoka forest is dominated by fruits. Habitat utilization differs markedly from both Berenty and Ambatotsirongorongo forest. Changes in ring-tailed lemurs' behaviour and distribution at Berenty reserve are partly due to the competition with the introduced brown lemurs. This situation has resulted in a niche partitioning between both species by creating a bimodal niche for ring-tailed lemurs: the marginal habitat and the closed canopy forest. The comparisons with ecological mechanisms and evolution of Bealoka and Ambatotsirongorongo forests show that Berenty has shifted from a situation more like Bealoka's to a situation more like natural sympatry.

Selective timber harvesting in tropical rain forests is becoming increasingly common and plays an important role in integrating economic development needs and conservation goals. Understanding the effects of logging on forest ecosystems can contribute to the design of sustainable management techniques and minimise the negative effects of timber harvesting on wildlife. Despite this, few previous studies have attempted a detailed ecological investigation of the effects of logging on wildlife. Here I present the results of a comparative study carried out in logged and unlogged forest in the Budongo Forest Reserve (January 1993 - September 1994) investigating differences in blue monkey (Cercopithecus mitis stuhlmanni) ecology and habitat composition. The ecology of groups of blue monkeys in logged and unlogged forest was compared and attempts made to relate differences in ecology to differences in habitat composition and food availability. In Budongo, widespread selective felling of 'mahogany' (genus Khaya and Entandrophragma) over the last 60 years has had a considerable impact on the plant and animal communities, resulting in significant changes in vegetation communities and an increase in density of four primate species (Plumptre et al 1994). It is thought that unlogged forest tends towards a low species diversity (monodominant) forest type, with Cynometraa lexandria s the dominant tree species. In addition, logging in Budongo has typically been carried out at a relatively low intensity. These two factors have been important in determining the nature of the changes in vegetation composition and plant phenological patterns subsequent to logging. Noticeable among these differences are a higher tree species diversity and higher proportion of colonising tree species in logged forest relative to unlogged forest. As a result, blue monkeys in Budongo experience greater food availability, occupy smaller home ranges and attain a higher population density in logged forest. There are several considerations which are important when discussing the findings of this study in the context of forest management for timber production. Firstly, the unique nature of the vegetation in Budongo prior to logging, and the type of timber harvesting carried out, both play an important role in determining the response of the vegetation and wildlife communities. Secondly, although logging in Budongo may lead to an increase in the density of blue monkeys and other common generalist/frugivore species, it may have negative effects on other more ecologically specialised taxa. The findings of this study are discussed in the context of understanding the effects of management on the vegetation composition and blue monkey density in the Budongo Forest Reserve. The results support the observation that the effects of logging are complex and in some cases can even be beneficial to wildlife. Forest management should take into account prior knowledge of forest types and the likely response of wildlife communities. If tropical foresters are to satisfy economic development requirements and meet conservation goals then management must be applied with care and after some consideration of the potential effects on the ecosystem.

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