Aircraft Applications of Insecticides in East Africa. VIII.—An Experiment against the Tsetse Fly, Glossina swynnertoni Aust., in an isolated Area of Thronbush and Thicket

1954 ◽  
Vol 45 (3) ◽  
pp. 613-622 ◽  
Author(s):  
K. S. Hocking ◽  
G. F. Burnett ◽  
R. C. Sell
Keyword(s):  
East Africa ◽  
Apparent Density ◽  
Significant Degree ◽  
Tsetse Fly ◽  
Central Province ◽  
The North ◽  
Insecticidal Treatment ◽  
Bad Weather ◽  
Glossina Swynnertoni ◽  
Better Than

An isolated area of 2,200 acres of thicket and thronbush in the Central Province, Tanganyika, was treated from the air with a DDT-in-oil aerosol in an attempt to eliminate the tsetse fly, Glossina swynnertoni Aust. Eight applications of 0·25 lb. technical DDT per acre were planned to be done at fortnightly intervals.Delays due to unseasonal bad weather reduced this to seven at a slightly higher rate and over a longer-period.G. swynnertoni was reduced from an apparent density of about 7 to zero at the end of the second application. No flies were caught after the fifth application for a period of six months.It is not possible to say whether the few caught since then have been brought in or are the offspring of survivors of the insecticidal treatment.This experiment was more successful than that on the Galapo Block in the same ares, to a highly significant degree, and this is attributed to the vulnerability of the smaller population present. It was doubtfully better than the first treatment of the North Block, also in this area, because the increase in population in the latter block may have been assisted by immigration.

A Note on the Fly Areas of North Nyasa District

1939 ◽  
Vol 30 (2) ◽  
pp. 255-258
Author(s):  
S. G. Wilson
Keyword(s):  
East Africa ◽  
Present Article ◽  
Present State ◽  
Human Population ◽  
Tsetse Fly ◽  
Single Factor ◽  
The North ◽  
Factor Governing

In Nyasaland, as indeed in most territories in East Africa, the greatest single factor governing the distribution of both human population and stock is the presence of tsetse fly. Exact records, therefore, of the distribution of this fly are of importance. In the present article an attempt is made to summarise the present state of our knowledge regarding the prevalence of Glossina in the North Nyasa district.

Long-term fluctuations in numbers of the tsetse fly Glossina swynnertoni Austen

1962 ◽  
Vol 53 (1) ◽  
pp. 129-137 ◽  
Author(s):  
J. P. Glasgow ◽  
J. R. Welch
Keyword(s):  
Apparent Density ◽  
Seasonal Variations ◽  
Geometric Mean ◽  
Tsetse Fly ◽  
Wild Animals ◽  
Animal Populations ◽  
History Of ◽  
The Mean ◽  
Glossina Swynnertoni

The tsetse fly population of Block 9 at Shinyanga, Tanganyika, consisting of 40–50 square miles of thorn bush, was studied from 1935 to 1957 by means of fly-rounds with a total length of 30 miles. The mean annual apparent density (A.D.) of Glossina swynnertoni Aust., taken as the geometric mean of the 12 monthly figures, is plotted on a graph covering 23 years, together with data for 1930–36 from another block which, however, is only doubtfully comparable. Four peaks and five troughs occur on the graph of Block 9, the highest value being 18 times the lowest. The history of the natural and artificial events which have occurred in the block are detailed as far as they are known. The minimum A.D. was that of 1938, after a number of wild animals had died of rinderpest; thereafter, the A.D. rose for several years, in spite of certain anti-tsetse measures, and none of the fluctuations subsequent to 1938 can be associated with any natural or artificial event. The amplitude of the fluctuations is small compared with records in the literature for other animal populations, and their occurrence is irregular; the last peak observed was in 1954, but limited observations in 1959 gave catches little, if at all, below those of 1954.The data were also analysed for seasonal variations. The least monthly mean catch was that of November, the greatest, differing from the least by a factor of only 1·34, that of April. Earlier published accounts of G. morsitans Westw. (based, however, on relatively short periods) give later maxima and greater amplitudes. Annual and seasonal records of the percentage of teneral individuals among male flies and the percentage of females among non-teneral flies are also given, but these data cannot be interpreted at present.

Aircraft applications of insecticides in East Africa. Xvii. Airspray experiment with fenthion against Glossina morsitans Westw., G. swynnertoni Aust. And G. pallidipes Aust

1969 ◽  
Vol 58 (3) ◽  
pp. 431-438 ◽  
Author(s):  
N. S. Irving ◽  
J. S. S. Beesley
Keyword(s):  
East Africa ◽  
Active Ingredient ◽  
Tsetse Fly ◽  
Glossina Morsitans ◽  
Total Cost ◽  
Numerous Species ◽  
Glossina Swynnertoni ◽  
Made In

In an attempt made in 1966 to reduce the tsetse fly population in an experiment area of eight square miles in northern Tanganyika to a density low enough to permit safe settlement, undiluted technical fenthion (95% active ingredient) was applied three times at three-week intervals at 0.0041 gal. per acre from a Cassna 185 aircraft fitted with rotary atomisers. The total cost was £95 per sq. mile. Catches in the four weeks immediately following treatment on a flyround of 23,500 yd. sampling the area showed a reduction of over 90 per cent. when compared with those in the four weeks preceding treatment in the case of Glossina swynnertoni Aust. and G. pallidipes Aust. Five months after spraying, the reduction of the former species still exceeded 80 per cent, and that of the latter, 90 per cent. The reduction was smaller in G. morsitans Westw., the most numerous species; a fourth application would probably have improved the kill. The results are compared with those of an earlier experiment in the same area using endosulfan. Some settlement took place in the part of the area where G. swynnertoni predominated.

Aircraft Applications of Insecticides in East Africa. VII.—An Experiment against the Tsetse Flies, Glossina morsitans, Westw. and G. swynnertoni Aust., in the Rainy Season

1954 ◽  
Vol 45 (3) ◽  
pp. 605-612 ◽  
Author(s):  
K. S. Hocking ◽  
G. F. Burnett ◽  
R. C. Sell
Keyword(s):  
East Africa ◽  
Rainy Season ◽  
Diesel Oil ◽  
Tsetse Fly ◽  
Tsetse Flies ◽  
Glossina Morsitans ◽  
The North ◽  
Aerosol Mass ◽  
Number Of Factors ◽  
Coarse Aerosol

The “ North Block ” at Kikore, Central Province, Tanganyika, was treated with insecticide dispersed from an Anson 1 aircraft during the period 23rd January to 4th May 1951. The area consisted of some 4,000 acres of mixed bush, including about 230 acres of miombo, infested by two species of tsetse fly, Glossina morsitans Westw. and swynnertoni Aust.The insecticide used was equivalent to a 19·4 per cent. solution of technical BHC (equal to 2·45 per cent. γ isomer) in 50 per cent. diesel oil, 50 per cent. power kerosene. The solution was dispensed through a boom and nozzles under pressure as a coarse aerosol (mass median diam. 70 microns), at a nominal mean dose of 0·25 lb. technical BHC per acre per application. Eight applications were planned and seven completed.The first application was relatively ineffective, and for the second and subsequent cycles the emission rate was increased and over part of the block the swathe width was reduced. The result was a much improved kill but neither species of tsetse was exterminated.Owing to the number of factors involved, it is not possible to give any principal reason why this experiment was less successful than previous ones, but many of the difficulties encountered are inherent in rainy-season operations in East Africa.

Ketilidian structure and the rapakivi suite between Lindenow Fjord and Kap Farvel, South-East Greenland

2000 ◽  
pp. 50-59
Author(s):  
Brian Chadwick ◽  
Adam A. Garde ◽  
John Grocott ◽  
Ken J.W. McCaffrey ◽  
Mike A. Hamilton
Keyword(s):  
Coastal Region ◽  
Field Work ◽  
Natural Environment Research Council ◽  
East Greenland ◽  
The North ◽  
Tectonic Processes ◽  
Field Investigations ◽  
North Eastern ◽  
Bad Weather ◽  
North Eastern Part

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Chadwick, B., Garde, A. A., Grocott, J., McCaffrey, K. J., & Hamilton, M. A. (2000). Ketilidian structure and the rapakivi suite between Lindenow Fjord and Kap Farvel, South-East Greenland. Geology of Greenland Survey Bulletin, 186, 50-59. https://doi.org/10.34194/ggub.v186.5215 _______________ The southern tip of Greenland is underlain by the Palaeoproterozoic Ketilidian orogen (e.g. Chadwick & Garde 1996; Garde et al. 1998a). Field investigations in the summer of 1999 were focused on the structure of migmatites (metatexites) and garnetiferous granites (diatexites) of the Pelite Zone in the coastal region of South-East Greenland between Lindenow Fjord and Kap Farvel (Figs 1, 2). Here, we first address the tectonic evolution in the Pelite Zone in that region and its correlation with that in the Psammite Zone further north. Then, the structure and intrusive relationships of the rapakivi suite in the Pelite Zone are discussed, including particular reference to the interpretation of the controversial outcrop on Qernertoq (Figs 2, 8). Studies of the structure of the north-eastern part of the Julianehåb batholith around Qulleq were continued briefly from 1998 but are not addressed here (Fig. 1; Garde et al. 1999). The field study was keyed to an interpretation of the Ketilidian orogen as a whole, including controls of rates of thermal and tectonic processes in convergent settings. Earlier Survey field work (project SUPRASYD, 1992–1996) had as its principal target an evaluation of the economic potential of the orogen (Nielsen et al. 1993). Ensuing plate-tectonic studies were mainly funded in 1997–1998 by Danish research foundations and in 1999 by the Natural Environment Research Council, UK. The five-week programme in 1999 was seriously disrupted by bad weather, common in this part of Greenland, and our objectives were only just achieved. Telestation Prins Christian Sund was the base for our operations (Fig. 2), which were flown with a small helicopter (Hughes MD-500).

scholarly journals Crustal variability along the rifted/sheared East African margin: a review

2021 ◽  
Vol 41 (2) ◽  
Author(s):  
Maren Vormann ◽  
Wilfried Jokat
Keyword(s):  
East Africa ◽  
Shear Zone ◽  
Structural Changes ◽  
The South ◽  
East African ◽  
The North ◽  
Rifted Margins ◽  
Continental Block ◽  
Seismic Lines ◽  
Southeastern Madagascar

AbstractThe East African margin between the Somali Basin in the north and the Natal Basin in the south formed as a result of the Jurassic/Cretaceous dispersal of Gondwana. While the initial movements between East and West Gondwana left (oblique) rifted margins behind, the subsequent southward drift of East Gondwana from 157 Ma onwards created a major shear zone, the Davie Fracture Zone (DFZ), along East Africa. To document the structural variability of the DFZ, several deep seismic lines were acquired off northern Mozambique. The profiles clearly indicate the structural changes along the shear zone from an elevated continental block in the south (14°–20°S) to non-elevated basement covered by up to 6-km-thick sediments in the north (9°–13°S). Here, we compile the geological/geophysical knowledge of five profiles along East Africa and interpret them in the context of one of the latest kinematic reconstructions. A pre-rift position of the detached continental sliver of the Davie Ridge between Tanzania/Kenya and southeastern Madagascar fits to this kinematic reconstruction without general changes of the rotation poles.

Aircraft Applications of Insecticides in East Africa. IV.—The Application of Coarse Aerosols in Savannah Woodland containing the Tsetse Flies Glossina morsitans and G. swynnertoni

1953 ◽  
Vol 44 (4) ◽  
pp. 627-640 ◽  
Author(s):  
K. S. Hocking ◽  
H. C. M. Parr ◽  
D. Yeo ◽  
D. Anstey
Keyword(s):  
East Africa ◽  
Meteorological Conditions ◽  
The Other ◽  
Tsetse Flies ◽  
Small Populations ◽  
Central Province ◽  
Glossina Morsitans ◽  
Short Period ◽  
Savannah Woodland ◽  
Mass Median

Attempts have been made to eradicate the tsetse flies G. morsitans and G. swynnertoni from two blocks of savannah woodland situated in the Central Province of Tanganyika.The insecticides were applied from aircraft. Coarse aerosols were used, with mass median diameters of approximately 90 microns; droplet diameters varied from 4 microns to 250 microns approximately.Eight applications of insecticides were made at intervals of two weeks. Each application was carried out at a nominal dosage of 0·25 gallons per acre, which was equivalent to 0·20 1b. per acre of the p, p'isomer of DDT or 0·03 lb. per acre of the γ isomer of BHC.In the area treated with DDT it is possible that both species of flies were eradicated for a short period, but small populations were re-established there by immigrant flies. In the other block the reduction was not so great, but it is not considered that this was due to a lesser effectiveness of the BHC, but to a combination of circumstances that led to less effective applications.Some general observations are made upon the use of aircraft for this sort of work, particularly in connection with the effect of meteorological conditions.

scholarly journals The Geology of Portuguese Nyasaland

1922 ◽  
Vol 59 (5) ◽  
pp. 200-212
Author(s):  
Robert R. Walls
Keyword(s):  
Indian Ocean ◽  
East Africa ◽  
The South ◽  
The North ◽  
Dark Continent ◽  
The Indian Ocean

Portuguese Nyasaland is the name given to the most northern part of Portuguese East Africa, lying between Lake Nyasa and the Indian Ocean. It is separated from the Tanganyika territory in the north by the River Rovuma and from the Portuguese province of Mozambique in the south by the River Lurio. The territory measures about 400 miles from east to west and 200 miles from north to south and has an area of nearly 90,000 square miles. This territory is now perhaps the least known part of the once Dark Continent, but while the writer was actually engaged in the exploration of this country in 1920–1, the Naval Intelligence Division of the British Admiralty published two handbooks, the Manual of Portuguese East Africa and the Handbook of Portuguese Nyasaland, which with their extensive bibliographies contained practically everything that was known of that country up to that date (1920). These handbooks make it unnecessary in this paper to give detailed accounts of the work of previous explorers.

scholarly journals Social Condition of England during the Wars of the Roses

1902 ◽  
Vol 16 ◽  
pp. 159-200
Author(s):  
Vincent B. Redstone
Keyword(s):  
Social Life ◽  
English History ◽  
Class A ◽  
The North ◽  
The Arts ◽  
The Social ◽  
Wars Of The Roses ◽  
Social Habits ◽  
North And South ◽  
Better Than

The social life of the inhabitants of England during the years of strife which brought about the destruction of the feudal nobility, gave to the middle class a new position in the State, and freed the serf from the shackles of bondage, has been for some time past a subject of peculiar interest to the student of English history. If we desire to gain an accurate knowledge of the social habits and customs prevalent during this period of political disturbance, we cannot do better than direct our attention towards that part of the country which was the least affected by the contest between the Houses of York and Lancaster, the eastern district of England, which since the days of King John had enjoyed a remarkable immunity from civil war. Here the powerful lords of the North and South found little support; the vast estates of the old feudal barons were broken up into numerous independent manors. Moreover the arts of peace, in the shape of the mysteries of trade, manufactures, and commerce, widely flourished among the inhabitants of these regions.

scholarly journals History of Sleeping Sickness in East Africa

1999 ◽  
Vol 12 (1) ◽  
pp. 112-125 ◽  
Author(s):  
Geoff Hide
Keyword(s):  
East Africa ◽  
Molecular Data ◽  
Sleeping Sickness ◽  
Tsetse Fly ◽  
Tsetse Flies ◽  
Agricultural Practice ◽  
Molecular Approaches ◽  
History Of ◽  
The Stability ◽  
The Right

SUMMARY The history of human sleeping sickness in East Africa is characterized by the appearance of disease epidemics interspersed by long periods of endemicity. Despite the presence of the tsetse fly in large areas of East Africa, these epidemics tend to occur multiply in specific regions or foci rather than spreading over vast areas. Many theories have been proposed to explain this phenomenon, but recent molecular approaches and detailed analyses of epidemics have highlighted the stability of human-infective trypanosome strains within these foci. The new molecular data, taken alongside the history and biology of human sleeping sickness, are beginning to highlight the important factors involved in the generation of epidemics. Specific, human-infective trypanosome strains may be associated with each focus, which, in the presence of the right conditions, can be responsible for the generation of an epidemic. Changes in agricultural practice, favoring the presence of tsetse flies, and the important contribution of domestic animals as a reservoir for the parasite are key factors in the maintenance of such epidemics. This review examines the contribution of molecular and genetic data to our understanding of the epidemiology and history of human sleeping sickness in East Africa.

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