DOCSLIB.ORG

Onchocerciasis, and Other Simulium ~Cies in Southem Sudan

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Onchocerciasis, and Other Simulium ~Cies in Southem Sudan - .. ~ " ..... .J \, "'...!~ _t' .... ~ ....... lnsect predators of JarvaJ Simuilum damnosum Theobald, vector of onchocerciasis, and other Simulium ~cies in Southem Sudan . .' by -' Judith A. Schorscher Department of Entomology McGill University, Montref4, @ February 1985 A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfll1ment of the requirements for the degree of <9 Master of Science. f -1 - M.Sc. Judith A. Schorscher Dept. of Entomology , Insect predators of larval Simulium damnosum 5.1. Theobald, vector of oncho<:erciasis, and other Simulium spedes in Southem Sudan. ABSTRACT Over 800 aquatic jnsects associated ..vith the, larval stages of Simulium damnosum s.l. eollected' from Wau (Bahr-el-Ghazal Province), Southern Sudan, were disseèted and thek gut contents analysed to determine the importance of larval <:> 1 , black flies in their diet. , Rates of predation, numbers of different prey items in the diet, prey, preferences, variation of diet with age and seasonal distribution of the predaton were recorded. ln Southern Sudan the inseet exerting the greatest pressure on Jarval - Simuliidae is Cheumatopsyche digitata (Hydropsychidae: Trichoptera). It's j~portance may be attributed to it's high carnivory, it's preference for black fly larvae ôver other prey ite"ms and it's abundance. It is followed by 1 Ch. copiosa, a less carnivorous $pecies whose impact is due 'l'ainly to it's ~igh densities. Other insects with the potential to reduce blaek tly populations are Zygonyx Spa (t.ibellulidae: Odonata), Neoperla sp. (Perlidae: ~Iecoptera), and Cheumatopsyche Spa VlIJ. These three species, consumed the highest mean numt?er of black fly larvae pcr individual, and did not prey extensively on other important predators. Ali age :.---~ classes of Zygonyx were highly carnivorous and fed preferentially on Simulium Jarvae. However, Zygonyx, as weil as Neoperla and Cheumatopsyche Spa VIII , occurred in relatively low densities. ,----._-_ ........., _.._.- -_.-- -11- Les insectes pré dateur~ des larves de Simullum damnosum ,:tneobald, le vectetl( de l'onchocercose, et d'autres espèces de SjmuÎium, dans le Sud ~ Soudan. - . , RESUME Plus de 800 insectes aquatiques associé s aux stades pré imaglnaux de Slmultum damnosum 5.1. et collectlonés dans la région de Wau, province du Bahr~el-Ghazal (Sud Soudan), furent disèqués et leurs contenus stomacaux examtné!; pour détermtner l'importance des larves de Simulies dans leuf' régime alimentaire Les taux de prédation, le nombre de différentes protes dans l'estomac, les proies préferées, la variation du régime alimentaire avec l'age er la dlstnbutlon • '> saisonière des pré dateurs furent étudié s. L'espèce exerçant-la plus grande'- pression sur les populations pré imaglnales de Simulies est Cheumatopsyche digitata (Hydropsychldae: Trlchoptera). 50n_ importance . - stexplique par sa grande ,voracité, sa p~éterence pour les larves de Simulies et ses grands> nombres: Cette espèce est suivie par Cheumatopsyche copiosa, un I~secte moins vorace que son prOChe parent et dont l'impac~ peut surtout être attribué a sa haute densité. D'autes espèces q~,i ont te potentiel de réduire les populations de SlmulJes sont: Zygonyx $p. (libeUuJidae: Odonata), Neoperla sp. (Perlidae: Plecoptera) et CheumatopsYche sp. VItI. Ces trois espèces consomment les taux les plus é I,evé s de Simulies et ne se nourissent que rarement d'autres pré dateurs Importants. Les Zygonyx de toutes tailles sont exclusivement carnivo,res et se nourissent preterentieUement de larves de Simulium. Toutefois les dens! té s de Zygonyx amsl que de Neoperla et CheumatopsYche sp. VlII, sont relativement peu élevées. ------_ .._ ..... -. -----_._- _.. _--- -.- ---------- ~J -111- " Short title: PREDATORS OF LARVAL 8LACK PLIES IN SUDAN. by Judith A. SCHORSCHER " - .. "",< " i!''l,1 i ~ ~', f' 1 _" ":lV- AKNOWLEDGEMENTS The field work for this project was performed in Wau (Bahr-el-Chazal Region), Southern Sudan, in cooperation with the WHO (World Health Organization) project ~n "Research into the Effectivenes5 of LocaHzed Onchocerciasis Vector Control in Bahr-el-Ghazal Region, Sudan". The author was supported trom 1981 to 1983 by a Postgraduate Scholarship awarded by the Natural Science and Engineering Research Council of Canada. Throughout this project 1 received support and help from a large number of people. 1 would like to express my gratitude to the followmg persons: Dr. DavId J. LEWIS of McGill University, my thesis supervisor, for hlS support, cooperation and guidance. Dr. Frusal T. ABUSHAMMA, Deputy-Vice Chancellor, UnIVersity of Khartoum, my co-supervisor overseas, for his moral support and help with logistics and the organization of my research. Dr. Osman ABDELNUR, Senior Government Entomologist, National Public Health Laboratories, Khartoum and principal investigator of the onchocerciasis control project in Wau, who we1comed me to the project and provided me wlth information and Iiterature. Dr. Richard BAKER, WHO Consultant Entomologist, who shared with me ail the- facilities at his disposaI, his collections 'of associated fauna and his wealth of knowledge of Simullum ecology. 1 am grateful for his constant encouragement, fruitful discussion, enthusiasm and friendship. ! 1 , .-------- -v- " Dr. Kt.\MBAL from the Department of Zooiogy, University of Khartoum for hls kindness and praétlcal assistance wlth -nany mmor problems. The graduate students of the Departme"nt of Zoology, UnIversity of Khartoum, who welcomed me warmly and assisted me wherever they could. "'y special thanks go ta Ahmed e.l BAKRI, ABU GASM and HOUDA. "'Ir. Paul OCfLO, Mr. BatIsta 'JORO, \Ar. ElunaJ Ka}okole YOBü50N, \1r. John Joseph UCIN and \Ar. Nixon Ali MATTHEW k,mdly asslsted n'le tn the collection of specimens tram the river. Mr. OelLO and Mr. NORO also helped wlth the sortlng of specimens in the laboratory. would Iike ta express my appreclatlOn of thelrO thoroughness and competence. ~r. Splritu LEONE and Saeed Awad 15\1AIL participated as chauffeurs to most samplJng expeditlons. Mr. Ali Gasm el SID, felJow student m Wau for his kmdness tn provldmg me with extra specimens of Plecoptera nymphs from hls personal collection. 1 Dr. Terrie TAYLOR 0.0. physiclan wlth the Michigan State UnIversity Onchocercisis project in Wau, for her stimulating friendship and spint of sClentiflc " cooperation as weIl as her cheerful hospltality both in Khartoum and Wqu. Michigan State University for the loan of a binocular mIcroscope and laboratory space. J', Herr Rolf HAASE of the "Abili Girls Senior Secondary School, (\1bili, Bahr-el-Ghazal Province) for his generous hospitality and friendship, which greatly enhanced sampHng expeditions on the Sue River. The members of the JUR communities of Mbdi and 1\Iyiduk for their welcome and assistance in collecting specimens. -v~- Dr. T .R.E. SOUTHWOOD, Oxford University, England, for his welcome and assistance. The following members of the British Museum of Natural History, London for their prompt identification of specimens: Dr. P.C. BARNARD (Trichoptera), Dr. P.S. CRANSTON (Chironomidae), Dr. S.J. BROOKS (Odonata and Ephemeroptera). Dr. 'L. LANDS BURY of the Hope Department of Entomology, Oxford University, for identification of the Hemiptera. Dr. P.J. BOON, University of the West Indies, Kingston, for his interesttng corespondanre and for. forwarding me a copy of a manuscript in print as well as. ,J EM photographs of Trichoptera proventricular teeth. Dr. H.P. ZWICK, Limnologische Flussstation des Max-Plank-Instltüts fur Limnolo~}e, in Schlitz, West Germany, for identification of Plecoptera nym~hs. -, For numerous repr~nts on the taxonomy. of tropical HydrQpsychidae, Dr. B. /' STA TZNER, Zoologische Institut, Karlsruhe University, West Germany and nr. K. SCOTT, Albany Museum, Grahamstown, South Africa. Dr. René LeBERRE, Director WHO' Vector Control Unit, Geneva, for stimulating discussion, encouragement and support. Dr. J.-M. ELOUARD and Mr. F. GIB~N, Université de Paris-Sud, for sjlaring their extensive knowledge of ,aquatic invertebrates associated with the larvae of Simù1ium damnosum and providing me with unpublished manuscripts. -------- -vii - ~ r. P. LANGLOIS, Senior technician, Department of Entomology, \AcGill ,1 University, far;~'hls advice and assistance wlth ail aspects of photography. '1 '11 .. In Khartoum, Didier and Corinne RE'v\Y, for their frendship and help through dlfficult moments. Pascal GINAILHAC for his invaluable assistance with logistics, and Father Hubert BARBIER for his ald in shippmg equipment down ta Wau. David LEYIN- for his friendship, constant moral support and patient preof rèading of the text. DaVid GORDON and Gérald LAFLEUR, fellow students in the Department of Entomology, for. their assistance with statistics and the use of the computer. '\Ars. J. TAYLOR, Department of Entomology, Macdonald College, for patience and helpfulness. in printing the text. \ 1 Wayne FAIRCHILD and Richard WEBBER, feHow laboratory companions in the Department of Entomology, for théir ~e<tication ta providing entertaining ahd lively working conditions. " - - -_.. _--~_ .._,---_.-.~----- --------------------~ f' -vi i i- TABLE OP CONTENTS ABS'TRA.CT ••••••••' •••••••••• _ "le .................. ., ........................ i B!S1JItE •••••••• ., •••••~ •••••••••••••••••••••••••• ~ ••••••••••••••••••••• i'i ~ •••••••••••• _ ••••••••••.• _ ............................ iv . , ". LIST OF lICO'BBS ............. _ ....................- ......................... xi 1 LIST OP T.ABt.Es ••••••••••••••••••••••••••••••••••••••••••••••••••••••xiii
Load more

Recommended publications
  • (1979A, During Copulation Calopteryx Reproductive Tract (E.G. MILLER
    Adv. Odonatol. 1: 175-192 December 31, 1982 Genital structure, sperm competition and reproductive behaviour in some African libellulid dragonflies P.L. Miller Department of Zoology, University of Oxford, South Parks Road, Oxford 0X1 3PS, United Kingdom The structure of the penis (vesica spermalis) and of the female genital tract are described in two African libellulids. The 4th segment of the penis of and which Brachythemis lacustris possesses a flagellum paired cornua are retracted inside inflation a specialized chamber at rest. On they are shot of of abruptly out the chamber, and the flagellum is seen to possess a pair large barbs while the cornua have complex laterally- and proximally-direct- ed bristles. female The genital tract has an asymmetrically disposed sperm- athecal which the reach system may permit flagellum to only one sperm- atheca and withdraw from sperm it during copulation. In Nesciothemis farinosa the penis bears large inflatable sacs armed with numerous bristles of which serrated and dentate. In the female the some are spermathecae are inaccessible the but from males be to penis, sperm previous may packed down or removed from the bursa during copulation. B. lacustris copulates rapidly on the wing and the male guards the female closely during ovipos- ition. N. farinosa also copulates rapidly but on the ground and guarding during oviposition is weak and short-lived. The possible relationships be- of and tween copulation duration, intensity guarding sperm competition are discussed. INTRODUCTION WAAGE (1979a, 1982) has shown that during copulation males of Calopteryx maculata and C. dimidiata remove the sperm of pre- vious males from the female’s reproductive tract before they intro- their duce own, and similar behaviour may occur in many other dam- selflies (e.g.
    [Show full text]
  • Adhesion Performance in the Eggs of the Philippine Leaf Insect Phyllium Philippinicum (Phasmatodea: Phylliidae)
    insects Article Adhesion Performance in the Eggs of the Philippine Leaf Insect Phyllium philippinicum (Phasmatodea: Phylliidae) Thies H. Büscher * , Elise Quigley and Stanislav N. Gorb Department of Functional Morphology and Biomechanics, Institute of Zoology, Kiel University, Am Botanischen Garten 9, 24118 Kiel, Germany; [email protected] (E.Q.); [email protected] (S.N.G.) * Correspondence: [email protected] Received: 12 June 2020; Accepted: 25 June 2020; Published: 28 June 2020 Abstract: Leaf insects (Phasmatodea: Phylliidae) exhibit perfect crypsis imitating leaves. Although the special appearance of the eggs of the species Phyllium philippinicum, which imitate plant seeds, has received attention in different taxonomic studies, the attachment capability of the eggs remains rather anecdotical. Weherein elucidate the specialized attachment mechanism of the eggs of this species and provide the first experimental approach to systematically characterize the functional properties of their adhesion by using different microscopy techniques and attachment force measurements on substrates with differing degrees of roughness and surface chemistry, as well as repetitive attachment/detachment cycles while under the influence of water contact. We found that a combination of folded exochorionic structures (pinnae) and a film of adhesive secretion contribute to attachment, which both respond to water. Adhesion is initiated by the glue, which becomes fluid through hydration, enabling adaption to the surface profile. Hierarchically structured pinnae support the spreading of the glue and reinforcement of the film. This combination aids the egg’s surface in adapting to the surface roughness, yet the attachment strength is additionally influenced by the egg’s surface chemistry, favoring hydrophilic substrates.
    [Show full text]
  • Okavango) Catchment, Angola
    Southern African Regional Environmental Program (SAREP) First Biodiversity Field Survey Upper Cubango (Okavango) catchment, Angola May 2012 Dragonflies & Damselflies (Insecta: Odonata) Expert Report December 2012 Dipl.-Ing. (FH) Jens Kipping BioCart Assessments Albrecht-Dürer-Weg 8 D-04425 Taucha/Leipzig Germany ++49 34298 209414 [email protected] wwwbiocart.de Survey supported by Disclaimer This work is not issued for purposes of zoological nomenclature and is not published within the meaning of the International Code of Zoological Nomenclature (1999). Index 1 Introduction ...................................................................................................................3 1.1 Odonata as indicators of freshwater health ..............................................................3 1.2 African Odonata .......................................................................................................5 1.2 Odonata research in Angola - past and present .......................................................8 1.3 Aims of the project from Odonata experts perspective ...........................................13 2 Methods .......................................................................................................................14 3 Results .........................................................................................................................18 3.1 Overall Odonata species inventory .........................................................................18 3.2 Odonata species per field
    [Show full text]
  • 96 Composition and Abundance of Odonates At
    UNILAG Journal of Medicine, Science and Technology COMPOSITION AND ABUNDANCE OF ODONATES AT ALATORI STREAM SOUTH-WEST, NIGERIA *Adu B. W1, Kemabonta, K. A2 and Ogbogu, S. S3 1Department of Biology, Federal University of Technology, Akure, Ondo State. 2Department of Zoology, University of Lagos, Lagos State Nigeria 3Department of Zoology, Obafemi Awolowo University, Ile-Ife, Osun State Nigeria. *Email of Correspondence author: [email protected] Abstract Dragonflies and damselflies (Odonata) are sensitive to human disturbance both as adults that are on wings and as larvae that are aquatic. This attribute suggests their usage as assessment tool for determination of human disturbance within the ecosystem. Alatori stream in Akure Forest Reserve was studied from May 2008 to April 2010 in order to determine the water quality and abundance of Odonata species of the stream. Adults and larvae specimens were sampled throughout the sampling period. A total of 767 adult specimens and 108 larvae were collected. Only 45.4% of the penultimate and ultimate larvae collected eclosed (emerged) to teneral adults. The composition of Odonata families occurring at the stream showed that Libellulidae was the highest (281) followed by Chlorocyphidae (158) while the lowest was Megapodagrionidae (5). The occurrence of members of the families Megapodagrionidae, Chlorocyphidae and Calopterigididae indicates that the stream ecosystem can sustain species with narrow niches. Seven physico-chemical variables: temperature (water and ambient), pH, turbidity, electrical conductivity, dissolved oxygen, water current velocity and depth of the stream were examined and analysed. Analysis of variance (ANOVA) result revealed that conductivity, temperature and water depth played a major role in determining the community structure of odonate assemblage in the stream.
    [Show full text]
  • 1997, a Odonata, Specifically on the Dragonflies of Ghana Published
    67-86 Odonatologica 30(1): March 1, 2001 An annotated list of Odonata collected in Ghana in 1997, a checklist of Ghana Odonata, and comments on West African odonate biodiversity and biogeography G. O’Neill¹ and D.R. Paulson² 1 Department of Biology, University of Puget Sound, Tacoma, WA 98416, United States (present address: 14 Lehigh Ave., Wilmington, DE 19805, United States) 2 Slater Museum of Natural History, University of Puget Sound, Tacoma, WA 98416, United States; — e-mail: [email protected] Received August 8, 2000 / Revised and Accepted September 4, 2000 made 8 in southern Collections were at localities Ghana during the summer of 1997. coastal Three regions were sampled: savanna, wooded savanna, and rainforest. 71 spp. were collected, 24 of which are new for the country, bringing the Ghana to A of known from is list 123 spp. list spp. the country included. Trithemis dejouxi Pinhey, 1978, is raised to specific rank. Individual variation in Phaon iridipennis and Palpopleura lucia is quantified. West African Odonata biodiversity and biogeography are discussed. INTRODUCTION To four studies date, only have focused specifically on the dragonflies ofGhana (KARSCH, 1893;NEVILLE, 1960;MARSHALL& GAMBLES, 1977;D’ANDREA & CARFI, 1994). Little has been published about the biology of the species and list of known from occurring there, no species the country has been compiled. From these papers and others, especially PINHEY (1962a), 99 species ofOdonata have been recorded in Ghana to date. The landscape of Ghana varies from wet forest to dry savanna due to a sharp rainfall gradient. The southern portion of the country is covered by wet, semi- moist and semi-dry forests, while farthernorth, in central Ghana, forest gives way the tall short to grasses, shrubs, and scattered trees of the savanna (SAYER et al., Terrestrial exhibit 1992).
    [Show full text]
  • Multifunctional Adhesives on the Eggs of the Leaf Insect Phyllium Philippinicum (Phasmatodea: Phylliidae): Solvent Influence and Biomimetic Implications
    biomimetics Article Multifunctional Adhesives on the Eggs of the Leaf Insect Phyllium philippinicum (Phasmatodea: Phylliidae): Solvent Influence and Biomimetic Implications Thies H. Büscher * , Raunak Lohar, Marie-Christin Kaul and Stanislav N. Gorb Department of Functional Morphology and Biomechanics, Institute of Zoology, Kiel University, Am Botanischen Garten 9, 24118 Kiel, Germany; [email protected] (R.L.); [email protected] (M.-C.K.); [email protected] (S.N.G.) * Correspondence: [email protected] Received: 3 November 2020; Accepted: 24 November 2020; Published: 27 November 2020 Abstract: Leaf insects (Phylliidae) are well-camouflaged terrestrial herbivores. They imitate leaves of plants almost perfectly and even their eggs resemble seeds—visually and regarding to dispersal mechanisms. The eggs of the leaf insect Phyllium philippinicum utilize an adhesive system with a combination of glue, which can be reversibly activated through water contact and a water-responding framework of reinforcing fibers that facilitates their adjustment to substrate asperities and real contact area enhancement. So far, the chemical composition of this glue remains unknown. To evaluate functional aspects of the glue–solvent interaction, we tested the effects of a broad array of chemical solvents on the glue activation and measured corresponding adhesive forces. Based on these experiments, our results let us assume a proteinaceous nature of the glue with different functional chemical subunits, which enable bonding of the glue to both the surface of the egg and the unpredictable substrate. Some chemicals inhibited adhesion, but the deactivation was always reversible by water-contact and in some cases yielded even higher adhesive forces.
    [Show full text]
  • In Pesticide-Fished, Victoria, (Anisoptera)
    Odonalologica38(3): 261-265 September 1, 2009 Differences in Odonataabundanceand diversity in pesticide-fished, traditionally-fished and protected areas in Lake Victoria, Eastern Africa (Anisoptera) D.J. Martins¹’² 1 Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, 26 Oxford Street, Cambridge, MA, United States 2 Nature Africa Kenya (East Natural History Society), National Museums of Kenya, Museum Hill, Nairobi, Kenya [email protected] Received April 29, 2009 / Reviewed and Accepted June 6, 2009 The growinguse of pesticides for fishingis a currentpractice of concernfor biodi- in versity Eastern Africa. There is little information available, however, on the extent and effect of this on indicator like practice conspicuous groups dragonflies. Odon., the larval especially during stage, are particularly vulnerable to pesticides. This sur- found differences in both vey significant dragonfly abundance and diversity in bays ofLake Victoria that had been fished using pesticides. Only 1-2 dragonfly spp. can be found in in contrast with > 20 in areas routinely pesticide-fished spp. protected areas. This the detrimental effect of invertebrates. survey highlights pesticide fishing on INTRODUCTION Odonata have widely been viewed as useful indicators of water quality. They are vulnerable particularly to poor water quality in the larval stage both through direct and the larval the poisoning, as stages are obligate predators, through re- duction of their prey which are also susceptible to poisons (CORBET, 1983). High concentrations of inorganic pollutants and pesticides have been shown to affect different life-stages of odonates and application of insecticides is known to produce a direct effect of decrease in ©donate numbers from various studies as summarised by CORBET (1999).
    [Show full text]
  • Rapport D'inventaire Préliminaire Des Libellules Des Zones Humides Du Sud-Bénin
    IDF-Report 6 (2004): 1-6 1 Rapport d’inventaire préliminaire des libellules des zones humides du Sud-Bénin Sévérin Tchibozo Laboratoire d’écologie appliquée, Faculté des sciences agronomiques, Université d’Abomey- Calavi, 04 B.p. 0385 Cotonou, Bénin, E-mail: [email protected] Avec la collaboration de Klaas-Douwe B. Dijkstra Gortestraat 11, 2311 MS Leiden, The Netherlands, Telephone: +31-71-5130356, E-mail: [email protected] Summary Dragonflies were collected at ten localities in five counties (sous-préfectures) in southern Bénin and are presently identified. A total of 73 species were found, including 45 new records for the country. The list of the odonates of Bénin currently comprises 86 species although more than 100 can probably be expected. Introduction Depuis juin 1995 nous avons entrepris des travaux de collectes sur les Odo- nates du Bénin. A travers nos recherches sur Internet en mai 2001 nous avons déniché l’adresse du groupe de travail de l’Uicn sur les Odonates ce qui nous permis de garder un contact permanent avec Klaas-Douwe B. Dijkstra. Les Odonates sont des indicateurs des points d’eau et peuvent sauver la vie à plusieurs Humains du globe en cas de forte absence d’eau. Ils sont aussi un élé- ment important du fonctionnement des écosystèmes humides. L’inventaire des Odonates du Bénin va contribuer à la bonne connaissance de l’un des éléments de la diversité biologique de la faune arthropode d’Afrique de l’Ouest (Agence Béninoise pour l’Environnement & Centre Béninois pour le Développement Durable 1997) Les libellules ont été collectées pour la première au Dahomey (actuellement République du Bénin) par A.
    [Show full text]
  • Abiotic and Biotic Drivers of African Aquatic Insect Distribution
    Abiotic and biotic drivers of African aquatic insect distribution by Charl Deacon Dissertation presented for the degree of Doctor of Philosophy (Entomology) at Stellenbosch University Department of Conservation Ecology and Entomology, Faculty of AgriSciences Supervisors: Prof. Michael J. Samways and Prof. James S. Pryke March 2020 Stellenbosch University https://scholar.sun.ac.za Declaration By submitting this dissertation electronically, I declare that the entirety of the work contained therein is my own, original work, that I am the sole author thereof (save to the extent explicitly otherwise stated), that reproduction and publication thereof by Stellenbosch University will not infringe any third party rights and that I have not previously in its entirety or in part submitted it for obtaining any qualification. Date: March 2020 Copyright © 2020 Stellenbosch University All rights reserved i Stellenbosch University https://scholar.sun.ac.za Summary Freshwater habitats are disproportionately rich in biodiversity, and are among the most threatened, yet poorly protected ecosystems. Aquatic insects make up much of the total freshwater fauna and contribute greatly to ecosystem functioning. At the broad-scale, aquatic insect distribution is driven by combinations of traits, as well as regional climate gradients and historical landscape context. Locally, both aquatic insect species richness and diversity are driven by various aspects related to vegetation and to physiochemical environments. Effective conservation requires thorough understanding of species distribution patterns at various spatial scales. My overall aim here is to combine broad-scale, theoretical biogeography, and local- scale empirical ecology to investigate drivers of aquatic insect distribution across Africa. Species are often binarily classified as ‘widespread generalists’ or ‘narrow-range specialists’ based on their ecological traits.
    [Show full text]
  • Preliminary Monitoring Plan Gambia Basin EN
    INTEGRATION OF FRESHWATER BIODIVERSITY IN AFRICA’S DEVELOPMENT PROCESS: INFORMATION COLLECTION AND DEMONSTRATION SITES PRELIMINARY PLAN For the monitoring of FRESHWATER BIODIVERSITY IN THE GAMBIA BASIN Wetlands International Africa Rue 111, Zone B, Villa № 39B, BP.25581 DAKAR-FANN. SENEGAL [email protected] Preliminary Plan for Freshwater Biodiversity Monitoring in the Gambia river basin Page 1 December 2009 WORKING GROUP 1. Coordination team AGBLONON Gabin NIANE Mamadou NIANG-DIOP Fatimata WADE Mawade 2. Consultants Dr. NDIAYE Abdoulaye Dr. NIANG-DIOP Fatimata Dr. Niasse Farokh Dr. SARR Alassane Dr. SEGA Moussa FIGURE 1: GAMBIA BASIN Preliminary Plan for Freshwater Biodiversity Monitoring in the Gambia river basin Page 2 TABLE OF CONTENT 2. OBJECTIVE ................................................................................................................................................ 6 3. METHODOLOGY ................................................................................................................................... 6 3.1. Species and key habitats concepts .................................................................................................................. 6 3.2. Site selection criteria .............................................................................................................................................. 7 3.3. Species selection criteria ........................................................................................................................................ 7
    [Show full text]
  • IDF-Report 4 (1): 1- 10 1
    ISSN 1435-3393 IDF-Report Newsletter of the International Dragonfly Fund Volume 4 Number 1 May 2002 Contents GRAHAM S. VICK Preliminary biodiversity assessment of the odonate fauna of the Takamanda Forest Reserve, Cameroon 1-10 VIOLA CLAUSNITZER Dragonflies of East Africa 11-17 JENS KIPPING Dragonfly research in the Okavango Delta, Botswana 18-26 DIANE S. SRIVASTAVA & MICHAEL C. MELNYCHUK Ground to canopy distribution of bromeliad-dwelling Mecistogaster modesta larvae (Odonata: Pseudostigmatidae) in a Costa Rican rainforest 27-30 IDF-Report 4 (1): 1- 10 1 Preliminary biodiversity assessment of the odonate fauna of the Takaman- da Forest Reserve, Cameroon Graham S. Vick Department of Biology, Imperial College, Silwood Park, Ascot, Berks, SL5 7PY, United Kingdom INTRODUCTION Dragonflies (Odonata) are attractive insects which are ideal for biodiversity studies. They are sensitive to pollution and habitat disturbance. Their present- day distributions are the result of past geological events and climatic fluctuations. There are approximately 6500 species worldwide, classified in about 600 genera, but the African dragonfly fauna, with about 900 species and 125 genera, is generally considered to be impoverished compared with that of South-East Asia or Central and South America. This is probably caused by the long periods of aridity which occurred during the Pleistocene. Only drought- adapted species could survive in large areas of the continent. The upland mountain chain which runs into the Gulf of Guinea, receives very high rainfall; up to 1000 cm (400") in the vicinity of Mount Cameroon, and over 300 cm at Mamfe (Vick 1999) and the dry season is short (usually at least 50 mm of rain even in the driest month).
    [Show full text]
  • Undergone Important Building. These Points Have Important Historical
    Odonatologica 21(2): 165-180 June I. 1992 Dragonfly conservation in South Africa: a biogeographical perspective M.J. Samways Department of Zoology & Entomology, University of Natal, P.O. Box 375, Pietermaritzburg 3200, South Africa Received May 6, 1991 / Accepted September 8, 1991 Most of South the 153 African odon. spp. (the taxonomic status of 2 of which is African whose uncertain) are widespread elements, ranges extend into the southern of tip the continent especially along the eastern seaboard, where there are suitable and moist climatic conditions. The endemics make 18% of the total warm up only (14% Zygoptera, 4% Anisoptera). The is well-known Cape, which for its high level of endemicity in many plant and animal makes 9% of the total odon. fauna. 4 groups, up only zygopteran and I endemics listed in 1990 anisopteran Cape are the 1UCN Red List, Also listed is I montane Natal Drakensberg endemic zygopteran and 1 highly localized coastal Natal anisopteran. Many of the endemics occur in water catchment wilderness areas or nature reserves, and are not immediatelythreatened with extinction, although the long- -term globalchanges are of particular concernfor southern African spp. Much further research is required on the exact distribution and abundance of all spp., especially the lUCN-catagorized ones. Although loss of wetlands has been severe in South Africa, farm dams the benefitted A scheme have, on contrary, many spp. pilot to develop a in also dragonfly reserve a botanic garden is underway. INTRODUCTION South Africa is the southern tip of the large continentof Africa. This southern tip has been isolated from neighbouring continents for many tens of millions of years and has undergone important mountain building.
    [Show full text]