Faunistic studies

An update on the work undertaken by the authors, Macan and Hynes, over the past year. Macan provides details of additional work undertaken since his publication of faunistic work on adult animals, including details on additional field data, further developments of the conclusions intially drawn and further comparisons with fauna of the highlands of Scotland. Two histograms are provided showing succession of Corixidae in two separate waterbodies. Habitat conditions are also discussed for this species and a number of locations are mentioned including, Blelham Tarn, Derwentwater and Rusland Moss. An update on stonefly work undertaken by Hynes is provided, specifically stomach contents of nymphs and habitat preference. Details are also given of aquatic insects being breed by the staff for research.

The cost of quinine Cinchona pubescens control on Santa Cruz Island, Galapagos

We analyse the cost of controlling the invasive quinine tree Cinchona pubescens Vahl in the highlands of Santa Cruz Island, Galapagos. Control costs in ten 400 m2 plots formed the basis for estimating the cost of control over the whole island. In the plots, densities were 2100–24,000 stems/ha (stems >150 cm tall) and 55,000–138,000 stems/ha (all size classes combined). Control involved uprooting small plants, and applying of a mix of metsulfuron methyl and picloram to cut stumps or to machete cuts in the bark of larger trees. These methods are presently used by Galapagos National Park field crews to control quinine. Costs (in man hours, herbicide and US$) were related to stem density; the density of stems summed across four height classes was a better predictor of costs than density of any one size class. Regressions (on all size classes combined) formed the basis for predictive models of costs. Costs ranged from $14 to $2225 per ha depending on stem density. The amount of herbicide (active ingredient/ha) that must be applied to high density stands of quinine is higher than typical rates of application in an agricultural setting. The cost of treating all existing plants once across quinine’s known range on Santa Cruz Island (c. 11,000 ha) was estimated at c. US$1.65 million. CDF Contribution Number 1013.

Results of the Austrian-Ceylonese hydrobiological mission 1970 of the 1st Zoological Institute of the University of Vienna (Austria) and the Department of Zoology of the Vidyalankara University of Ceylon, Kelaniya. Pt. 3. Uber einige wassermilben aus Ceylon (Hydrachnellae, Acari)

In the study are described five species of watermites, collected by the Austrian-Ceylonese hydrobiological mission 1970 in torrents of the highlands of south-west Sri Lanka. The species are: Torrenticola (Monatractides) pusta Cook, 1967, T.(M.) Oxystoma hamata (Lundbald, 1941), T.(M.) ceylonensis nov. spec., Atractides schwoerbeli Lundbald, 1969 and Arrenurus (Micruracarus) madaraszi Daday, 1898.

The challenge of Lake Chilwa

Lake Chilwa and its environs present a unique challenge to science for two reasons: 1. The welfare of its people and the fish and crops on which they depend on incomes as well as subsistence are dominated by the vagaries of the periodic rise and fall of the lake. Inyears of high level the lake provides a relatively good living for the people of the plain and the fish is a major source of dietary protein for the densely populated Shire Highlands. Fish catches and fish consumption decline in years of low lake level. Could knowledge of the biology of the lake and the hydrology of the lake basin assist in stabilizing the fishing industry? 2. The area is underdeveloped, with the traditional matrilineal way of life, but it has considerable potential for a fishing industry, for agriculture, for livestock, for bird preservation and tourism and possibly, at some future date, for minerals. How can these interests be reconciled and in what order should developments take place?

Filariasis research annual report 1952

This 1952 report gives details of findings in the Southern and Southern Highlands Provinces. Accordingly in this publication a return is made to the more usual method of presentation, a summary being given of work done, with detailed sectional reports.