Browsing by Author "Howell, Kim"

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    Abnormal white colouration in three species of insectivorous African bats
    (2009-08) Howell, Kim
    There are numerous reports in the literature of albinism in bats (Setzer, 1950; Verschuren, 1955; Walley, 1971, and Cerveny & Burger, 1977). Not all records of white or partially white bats represent cases of albinism as defined by Egoscue & Lewis (1 968), and emphasized by Quay (1970). Many authors note records of “partial albinism” which are actually examples of non-albinistic abnormalities in colouration. Of the two most recent reviews, only that of Walley (1971) correctly records separately examples of albinism
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    Abundance and roosting ecology of chameleons in the Eastern Arc Mountains of Tanzania and potential effects of harvesting
    (2011-12) Patrick, David A.; Shirk, Philip; Vonesh, James R.; Harper, Elizabeth B.; Howell, Kim
    Harvesting of chameleons from the East Usambara Mountains of Tanzania for the exotic pet trade is of concern due to the high rates of habitat loss in this region and the fact that many of the species are endemic or near endemic to this isolated montane forest. Export of the majority of chameleons found in the East Usambaras is regulated by their listing under CITES Appendix II. To ensure harvesting is sustainable, however, greater knowledge of the ecology of species is needed. We conducted this study in and around Amani Nature Reserve in the East Usambara Mountains during August 2009. We used transects on the forest edge and interior to gather baseline data relating to the ecology of chameleons and to assess if any effects of harvesting on populations could be detected. We compared abundance of chameleons between forest edge and interior, the age/size of species, and sex-ratios between these two habitat types. We observed 108 chameleons during surveys, representing seven species. Some species were restricted to forest interior while others were only found on forest edges. When comparing age/size and sex ratios of the most valued species for the exotic pet trade, Trioceros deremensis, we found a strong female sex-bias in adults only, and that adult females were larger than adult males. This is in contrast to reports in published literature showing that males are capable of growing larger than females. Based on the low abundance of some species, we suggest careful consideration of future export quotas under CITES. Further investigation into the potential reasons for the size and sex-ratios of T. deremensis is also needed.
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    An albino bat Hipposideros ruber Noack, from Tanzania
    (1974-05) Howell, Kim; Mainoya, J. R.
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    The Ambangulu Forest, West Usambara Mountains, Tanzania: A Threatened Eastern Arc Forest. Oryx
    (1995-06) Goodman, Steven M.; Stanley, William T.; Newmark, William D.; Howell, Kim
    Ambangulu Forest is one of the few remaining tracts of natural forest between 800 and 1200 m in the West Usambara Mountains of Tanzania. It may be the biologically richest area in the region but it is threatened by illegal felling of timber trees, wind damage, grazing and browsing livestock, and collection of fuel-wood and building poles. A proposed project aims to protect the forest and benefit local people at the same time.
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    AMPHIBIANS OF THE AFROTROPICAL REALM
    (2008-11) Andreone, Franco; Channing, Alan; Drewes, Robert; Gerlach, Justin; Glaw, Frank; Howell, Kim; Largen, Malcolm; Loader, Simon; Lötters, Stefan; Minter, Leslie; Pickersgill, Martin; Raxworthy, Christopher J.
    Due to their permeable skin few amphibians are able to tolerate dry or salty conditions, a characteristic that has prevented most species from colonising oceanic islands. The most diverse oceanic island amphibian fauna is found in the Seychelles, an archipelago of about 115 granitic and coralline islands in the Indian Ocean, some 1,600km east of mainland Africa, and northeast of the island of Madagascar (Figure 1). Eleven native amphibian species have been recorded from the Seychelles islands, comprising both recent colonists and ancient endemics. Recent colonization by one species, the Mascarene Grass Frog Ptychadena mascariensis (LC), is probably the result of human introduction (Vences et al. 2004) in the 1800s, whilst the endemic Seychelles Treefrog Tachycnemis seychellensis (LC) is believed to be descended from a natural colonist from Madagascar (Vences et al. 2003). The remaining spe- cies are all ancient endemics that have probably existed on the island since their isolation from the Indian landmass some 65 million years ago. These species comprise the endemic frog family Sooglossidae and seven species of burrowing caecilians (Order Gymnophiona). Sooglossidae are an exceptional family in several respects. Four species are currently recognized in two genera, although recent morphological and mo- lecular data suggests that a further three species remain to be described and that the genera need to be redefined. They are all small frogs, with Gardiner's Frog Sooglossus gardineri (VU) among several species up for contention as the world's smallest frog (with adults being as small as 9mm in length). All sooglossids are found in the damp forests of the two highest islands, Mahé and Silhouette. These habitats have only seasonal or fast-flowing stems, and the sooglossids have abandoned the normal frog life-cycle in favour of ter- restrial development. The Seychelles Frog Sooglossus sechellensis (VU) lays its eggs on land and the female carries the tadpoles until they develop into frogs. Sooglossus gardineri is even more specialized, with the male guarding terrestrial eggs that hatch into 3-mm long froglets; the entire tadpole stage is passed within the egg. Thomasset's Seychelles Frog Nesomantis thomasseti (VU) has recently been discovered to have a very similar breeding strategy, but nothing is known of the reproductive behaviour of the Seychelles Palm Frog S. pipilodryas (VU). This latter species is the most recently described of the Seychelles amphibian species, having been discovered in 2000 (Gerlach and Willi 2002). It lives in the axils of endemic palms where it lay protected from discovery by the dense spines of the palm leaves. It is the only arboreal sooglossid, the other species all being associated with crevices in boulder fields or the leaf-litter and root-mat of the forest floor. The caecilian fauna of the Seychelles islands comprises six species in three endemic genera. Not surprisingly, and as with caecilians in general (see Essay 1.3), these are the least well known of all Seychelles amphib- ians. Their burrowing habits make them difficult to locate and study. For most species, their distributions are reasonably well defined and there are some observations of breeding habits. Different species appear to show the full range of reproductive strategies, form aquatic larvae, thorough to ter- restrial larvae and direct development. The limited ecological data available indicate that Grandisonia alternans (LC) is a widespread species occurring in all habitats and Hypogeophis rostratus (LC) is a similar generalist, although more associated with lowland habitats. In contrast, Praslina cooperi (VU) and some of the small Grandisonia species appear to be specialists of the high forest. Current research into this group is attempting to develop monitoring methods and to identify aspects of their ecology that are of importance to their conservation. Half of Seychelles amphibians are threatened due to their naturally restricted ranges and deteriorating habitats (five species are categorised as Least Concern, 5 Vulnerable and one Endangered). The sooglossid frogs and the caecilian Praslina cooperi have particularly restricted ranges, being associated only with the damper rain-forests. Habitat deterioration is a significant threat to the caecilian Grandisonia brevis (EN), which has a re- stricted range and occurs in habitats that are suffering from ongoing invasion by alien plant species. In addition, there is some suggestion that changes in rainfall patterns may have impacts on some species, which may result from mid-year declines in rainfall restricting the activity and distribution of the rain-forest specialists (Gerlach 2000). Losses of several areas of marsh habitats have probably caused population declines in some species, such as another caecilian Grandisonia alternans (Gerlach 2000). There have been a number of successful conservation programmes in Seychelles, concentrating mainly on birds. Critically Endangered species have been rescued from extinction by limited habitat management, but mostly by inter-island transfers. These programmes have been to the benefit of spe- cies such as the Seychelles Magpie-robin Copsychus seychellarum and the Seychelles White-eye Zosterops modesta. Such options are not available for the amphibians due to their close dependence on their high forest or marsh-land habitats. Consequently, preservation of their habitat is essential; most species are present in protected areas, although habitat management is still required to control the spread of invasive plant species. The island with the highest diversity of amphibians (Silhouette) is currently unprotected and designation of this island as a national park would significantly enhance amphibian conservation in Seychelles. To date, there has been no evidence of any sudden amphibian decline in Seychelles, although the potential impact of an invasion by chytridiomycosis would be considerable. Monitoring programmes are in place for the frogs, and are being developed for the caecilians. Updates on research and conservation progress can be found at http://members.aol.com/jstgerlach/herps.htm
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    Bat assemblages in Tanzanian coastal forests
    (1997-12) Cockle, A.; Kock, D.; STUBLEFIELD, L.; Howell, Kim; Burgess, Neil D.
    Bat species lists were compiled in 17 small coastal forests of Tanzania, eastern Africa, between 1990 and 1992. Forty-six bat species were recorded, with up to 15 species in a single forest. Eight forests were sufficiently studied for comparisons to be made on species frequencies and species diversity. Regional diversity was 2.74, and local diversities ranged between 1.55 to 1.97. Many species were remarkably unevenly distributed. Records of biogeographical significance for Tanzania were: confirmations of Myotis tricolor, Tadarida brachyptera, Myonycteris relicta, Rhinolophus deckenii and Kerivoula africana, and first records of Scotophilus nigrita alvenslebeni, Hipposideros cyclops and Cloeotis percivali.
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    Bats are Not Birds – Different Responses to Human Land-use on a Tropical Mountain
    (2015-05) Bonitz, Maria H. B.; Ferger, Stefan W.; Gaese, Katrin B.; Tschapka, Marco; Howell, Kim; Kalko, Elisabeth K. V.
    Land-use intensification has consequences for biodiversity and ecosystem functioning, with various taxonomic groups differing widely in their sensitivity. As land-use intensification alters habitat structure and resource availability, both factors may contribute to explaining differences in animal species diversity. Within the local animal assemblages the flying vertebrates, bats and birds, provide important and partly complementary ecosystem functions. We tested how bats and birds respond to land-use intensification and compared abundance, species richness, and community composition across a land-use gradient including forest, traditional agroforests (home garden), coffee plantations and grasslands on Mount Kilimanjaro, Tanzania. Furthermore, we asked how sensitive different habitat and feeding guilds of bats and birds react to land-use intensification and the associated alterations in vegetation structure and food resource availability. In contrast to our expectations, land-use intensification had no negative effect on species richness and abundance of all birds and bats. However, some habitat and feeding guilds, in particular forest specialist and frugivorous birds, were highly sensitive to land-use intensification. Although the habitat guilds of both, birds and bats, depended on a certain degree of vegetation structure, total bat and bird abundance was mediated primarily by the availability of the respective food resources. Even though the highly structured southern slopes of Mount Kilimanjaro are able to maintain diverse bat and bird assemblages, the sensitivity of avian forest specialists against land-use intensification and the dependence of the bat and bird habitat guilds on a certain vegetation structure demonstrate that conservation plans should place special emphasis on these guilds.
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    The biological importance of the Eastern Arc Mountain of Tanzania and Kenya
    (2007-01) Burgess, Neil D.; Butynski, Thomas M.; Cordeiro, Norbert J.; Doggart, Nike; Fjeldså, Jon; Howell, Kim; Kilahama, Felician B.; Loader, Simon; Lovett, Jon C.; Mbilinyi, Boniface P.; Menegon, Michele; Moyer, David; Nashanda, Evarist; Perkin, Andrew; Rovero, Francesco; Stanley, William T.; Stuart, Simon N.
    The Eastern Arc Mountains are renown in Africa for high concentrations of endemic species of animals and plants. Thirteen separate mountain blocks comprise the Eastern Arc, supporting around 3300 km2 of sub-montane, montane and upper montane forest, less than 30% of the estimated original forested area. At least 96 vertebrate species are endemic, split as follows: 10 mammal, 19 bird, 29 reptile and 38 amphibian species. This includes four endemic or nearly endemic species of primate – the Sanje Mangabey, the Iringa Red Colobus, the Mountain Galago and the new Kipunji monkey that forms its own monotypic genus. A further 71 vertebrate species are near-endemic. At least 800 vascular plant species are endemic, almost 10% of these being trees. These endemics include the majority of the species of African violet – Saintpaulia, a well-known flowering plant in Western households. An additional 32 species of bryophytes are also endemic. Many hundreds of invertebrates are also likely to be endemic, with data for butterflies, millipedes and dragonflies indicating potential trends in importance. Seventy-one of the endemic or near-endemic vertebrates are threatened by extinction (8 critical, 27 endangered, 36 vulnerable), with an additional seven wide ranging threatened species. Hundreds of plant species are also threatened. Most Eastern Arc endemics are closed-forest specialists and comprise taxa with an ancient history and those of more recent origin, including some possessing ancient affinities with taxa from West Africa, Madagascar, and even South America and Southeast Asia. Mountain block prioritisation for biodiversity conservation shows that Udzungwas, East Usambaras and Ulugurus are the most important blocks, with other important blocks being the Ngurus and West Usambaras. Rankings are correlated closely with the area of remaining forest. Most of the remaining forest is found within nearly 150 Government Forest Reserves, with 106 of these managed nationally for water catchment, biodiversity and soil conservation and where forest exploitation is not allowed. Outside these areas most forest has been cleared, except in small village burial/sacred sites, a few Village Forest Reserves, and inaccessible areas. In most Eastern Arc Mountains the local populations have not encroached beyond the reserve boundaries to develop farms, but forest resources within the boundaries are used for fuel and building materials and some forests are heavily degraded. Fire is also a problem as it enters and destroys forests during the dry seasons. The future of the biodiversity on the Eastern Arc Mountains is closely tied to management policies and capacity of the Tanzania Forestry and Beekeeping Division, Tanzania National Parks Authority, and Kenya Forest Department. Supporting these agencies in their mandated job is an essential conservation investment over the longer term.
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    A celebration of the works of John Charles Poynton
    (2013-05) Loader, Simon; Menegon, Michele; Howell, Kim; Müller, Hendrik
    The 15th meeting of the African Amphibian Working Group celebrated thecontributions of John Charles Poynton to African Herpetology. The meeting, inTrento, Italy, was timed to commemorate John’s 81st birthday (in May 2012), and hepresented a keynote speech that focused on a topic that has long fascinated him  theAfrotemperate amphibian fauna. His presentation is published here, in a modifiedform, for this special issue of African Journal of Herpetology (Poynton 2013). Otherpapers on the main themes of John’s research are also included in this issue, whichinclude biogeography (Loader et al. 2013; Schreiner et al. 2013), taxonomy (Cruzet al. 2013) and morphology (Wilkinson et al. 2013)
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    Community and population-level responses of an Afromontane chameleon assemblage to forest fragmentation
    (2012-08) Shirk, Philip; Patrick, David A.; Howell, Kim; Harper, Elizabeth B.
    Background/Question/Methods Habitat modification in the form of fragmentation and loss is a leading cause of biodiversity decline. The basic predictions from island biogeography theory that species richness and population size decrease with declining area and increased isolation have received considerable support. However much of this research has focused on birds and mammals in temperate regions or the Neotropics, limiting our ability to generalize to other taxa and regions. Reptiles in particular are understudied and have not yet shown the clear response of other taxa. Here we examine the community and population-level responses of an Afromontane chameleon assemblage to forest fragmentation. The East Usambara Mountains of Tanzania have high rates of endemicity in a forested landscape fragmented by logging, tea plantations, and small-scale farming. Remaining fragments have been isolated for approximately 80 years, making it unlikely that short-lived species retain any extinction debt. Within this fragmented habitat are eight species of chameleon, many of which are of conservation concern. We used repeated distance-based sampling in a large forest block and 11 forest fragments in order to estimate species’ densities and overall richness. This allowed us to quantify the population and community-level responses to habitat fragmentation while accounting for differences in detectability. Results/Conclusions Chameleon richness decreased with both decreasing fragment size and with increasing isolation. The chameleon communities of 10 of the 11 forest fragments were subsets of the community of the largest block sampled, suggesting that smaller fragments contribute little to landscape-level biodiversity. The densities of Trioceros deremensis, Rhampholeon temporalis, and the combination of Kinyongia matschiei and K. vosseleri are better predicted by fragment area alone than by any model including isolation, but species’ responses differ. R. temporalis shows a strong decrease in density with decreasing fragment area, while T. deremensis’ density decreases only slightly with decreasing fragment area. Neither species was found in the two smallest forest fragments (<3.5 ha), suggesting that each has a similar fragment area threshold. Kinyongia spp., which are commonly found in disturbed habitat, show an increase in density as fragment area decreases. Due to the alteration of chameleon communities in smaller fragments, with declines in species richness and species-dependent changes in density, several small blocks are not equivalent to a single large block. A possible functional cause for this non-equivalency is altered vegetation characteristics in smaller fragments. In some cases the vegetation variables are more strongly correlated with species’ density than is fragment area.
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    Confronting Amphibian Declines and Extinctions
    (2006-07) Mendelson, Joseph R.; Lips, Karen R.; Ronald, Gagliardo W.; Rabb, George B.; Collins, James P.; Diffendorfer, James E.; Daszak, Peter; Ibanez, Roberto D.; Zippel, Kevin; Lawson, Dwight; Wright, Kevin M.; Stuart, Simon N.; Gascon, Claude; Da Silva, Helio R.; Burrowes, Patricia A.; Joglar, Rafael L.; La Marca, Enrique; Lotters, Stefan; Du Preez, Louis; Weldon, Ché; Hyatt, Alex D.; Mahecha, J.V. R.; Hunt, Susan; Robertson, Helen; Lock, Brad; Raxworthy, Christopher J.; Frost, Darrel; Lacy, Robert C; Alford, Ross A.; Campbell, Jonathan A.; Olea, Gabriela P.; Bolaños, Federico; Domingo, Jose J. C.; Halliday, Tim; Murphy, James B.; Wake, Marvalee H.; Coloma, Luis A.; Kuzmin, Sergius; Price, Mark S.; Howell, Kim; Lau, Michael W.N.; Pethiyagoda, Rohan; Boone, Michelle; Lannoo, Michael; Blaustein, Andrew R.; Dobson, Andy P.; Griffiths, Richard A.; Crump, Martha L.; Wake, David; Brodie Jr, Edmund D.
    Amphibian declines and extinctions areglobal and rapid: 32.5% of 5743 de-scribed species are threatened, with atleast 9, and perhaps 122, becoming extinct since1980 (1). Species have disappeared across theentire taxonomic group and in nearly all regionsof the planet. These figures are probably under-estimates as entire clades of species are threat-ened. For example, of the 113 species of harle-quin toads (genus Atelopus), 30 are possiblyextinct, and only 10 have stable populations (2).Nearly a quarter of known amphibian specieswere deemed “data-deficient” with respect toconservation status in the recent global assess-ment (1). Losing biodiversity at this taxonomicscale impacts ecosystem goods and services[e.g. (3, 4)]. As amphibian species disappear, wealso lose their untapped potential for advances inbiomedicine and biotechnology in general (5). Losses result from familiar threats (land-usechange, commercial overexploitation, and exoticspecies) and from the emerging infectious dis-ease chytridiomycosis, caused by the fungusBatrachochytrium dendrobatidis (Bd). Pre-dictions are that within 4 to 6 months of Bdarrival at a site where it has not previously beenpresent, ~50% of amphibian species and ~80%of individuals may disappear (6). Global climatechange may be encouraging local conditionsideal for Bd’s persistence and/or spread (7), com-mercial trade of wildlife may also contribute (8),and pollution may increase susceptibility ofspecies to pathogens (9, 10). Traditional pro-grams and current laws and policies alone areinsufficient to address global threats that crossboundaries of reserves and nation
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    A critically endangered new species of Nectophrynoides (Anura: Bufonidae) from the Kihansi Gorge, Udzungwa Mountains, Tanzania
    (1997-12) Poynton, John C.; Howell, Kim; Clarke, Barry T.; Lovett, Jon C.
    A new species of the Tanzanian ovoviviparous dwarf toad Nectophrynoides is described from the Kihansi River Gorge in the Udzungwa Mountains, and a key to the genus provided. The new species, currently known only from small patches of spray-dependent wetland vegetation associated with Kihansi Gorge waterfalls, is probably the most vulnerable member of this genus on account of the Lower Kihansi Hydropower Project which is due to go on-line in 1999. This project will significantly reduce the river flow into the gorge and consequently the amount of spray that maintains a unique plant and animal community. Measures are suggested for improving chances of long-term survival of the species.
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    The Current Status of the Rare Usambara Mountain Forest-Viper, Atheris Ceratophorus WERNER, 1895, Including A Probable New Record Of A. Nitschei Rungweensis BOGERT, 1940, And A Discussion Of Its Validity (Reptilia, Serpentes, Viperidae)
    (1981-12) Rasmussen, Jens B.; Howell, Kim
    The recent collecting of five specimens of Atheris ceratophorus WERNER, 1895, together with an examination of material already deposited in various museums documents new records outside the Usambara Mountains to which the species had been believed to be endemic. Lepidosis and hemipenial characters have been investigated and tabulated to give an impression of the intraspecific variation. The data of the new specimens provide some information on the natural history of this species. The validity of A. nitschei rungweensis is discussed and a probable new record is given.
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    Description of A New and Critically Endangered Species of Atheris (Serpentes: Viperidae) From the Southern Highlands of Tanzania, With an Overview of The Country's Tree Viper Fauna
    (2011-12) Menegon, Michele; Davenport, Tim R. B.; Howell, Kim
    A new species of arboreal forest viper (Serpentes: Viperidae: Atheris) from a forest fragment in the Southern Highlands of Tanzania is described and named Atheris matildae sp. nov. The species resembles the forest horned viper, Atheris cer-atophora Werner, by bearing horn-like supraciliary scales but it differs in size, body proportions, scalation, scale ultra-structure, and distribution. Genetic divergence is also assessed and the two species have an estimated divergence time of approximately 2.2 million years. An overview of the genus Atheris in Tanzania, including new distribution data, is pre-sented and the conservation status of the new taxon is discussed
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    A Field Guide to the Reptiles of East Africa. Kenya, Tanzania, Uganda, Rwanda and Burundi
    (2001-12) Drewes, Robert; Spawls, Stephen; Howell, Kim; Ashe, James
    This book breaks new ground: it is the first complete listing and guide to all the known reptiles of the five East African countries (Kenya, Tanzania, Uganda, Rwanda, Burundi.) Written by expert East African herpetologists, it incorporates virtually all known information on the East African reptile fauna. Nearly 500 high-quality color photographs illustrate most of the species involved, many of which have never been illustrated in color before. Keys and introductory essays are included for all orders, families, genera, and species, giving clear introductions for every group. There is an individual account for each species, describing its appearance, habits, and habitat, accompanied by a map showing its known distribution within East Africa and notes indicating its Africa-wide distribution as well. Hence this book will be useful not only in East Africa, but in the surrounding countries as well, for which no reptile guides exist. In addition, the descriptions of dangerous snakes include a section on their venom. A comprehensive appendix discusses aspects of snakebite risk and treatment in East Africa and the do's and don'ts of first aid
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    Food resources and vegetation structure mediate climatic effects on species richness of birds
    (2014-04) Ferger, Stefan W.; Schleuning, Matthias; Andreas, Hemp; Howell, Kim; Gaese, Katrin B.
    Aim Climate is widely recognized as a major predictor of species richness patterns along large-scale environmental gradients. Nevertheless, the mechanisms by which climate influences species richness are still a matter of debate. We disentangle whether climate influences species richness of birds directly via physiological limi-tations or indirectly via vegetation structure or the availability of food resources. Location Mount Kilimanjaro, Tanzania. Methods We recorded bird species richness along an elevational gradient from 870 to 4550 m a.s.l. We quantified local climatic conditions, vegetation structure and the availability of food resources, and applied path analysis to disentangle their direct and indirect effects on species richness of all birds, frugivores and insectivores. Results Overall, we recorded 2945 individuals from 114 bird species. Species richness of all birds was closely correlated with temperature, vegetation structure and invertebrate biomass and both direct and indirect (via vegetation structure and availability of food resources) climatic effects were important for the diversity of the whole, trophically heterogeneous bird community. The species richness of insectivorous birds was linked to vegetation structure and invertebrate biomass, while the richness of frugivores was strongly associated with fruit abundance. Climatic factors influenced bird species richness of both avian feeding guilds exclu-sively indirectly via vegetation structure and availability of food resources. Main conclusions We reveal the importance of trophic interactions for gener-ating species richness patterns along large-scale environmental gradients. Our results challenge the general assumption that temperature and water availability influence species richness mostly directly, and underscore the importance of veg-etation structure and the availability of food resources as principal mediators of climatic effects on species
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    The Forgotten ‘Coastal Forests’ of Mtwara, Tanzania: A Biologically Impoverished and Yet Important Ecosystem
    (2009-11) Wegner, Giulia; Howell, Kim; Davenport, Tim R. B.; Burgess, Neil D.
    Biodiversity surveys and the compilation of indigenous knowledge were conducted in eight previously unstudied proposed and already gazetted Forest Reserves of Mtwara Region, south-eastern Tanzania, from April to August of 2005. The results indicate relatively low biodiversity and endemism values in these forests, and high levels of forest disturbance. In most areas the original vegetation has been converted by clearance for cultivation and by fire, and has regenerated into degraded forms of Swahilian/Coastal Mixed Dry Forest, Swahilian/Coastal Brachystegia Forest and floristically impoverished Zambezian-Swahilian Brachystegia Woodland. Some Coastal Forest endemic and threatened species, however, occur in the degraded forest patches, such as east coast akalat Sheppardia gunningi, Reichenow's batis Batis mixta reichenowi, spotted flat-lizard Platysaurus maculatus, woodland toad Mertensophryne micranotis and the shrub Gardenia transvenulosa. The low proportion of endemic and threatened species recorded implies that these forests are of modest biological importance within the context of the Eastern Arc Mountains and Coastal Forests Biodiversity Hotspot. Nevertheless, local inhabitants depend heavily on the long-term
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    Histology of the frontal sac in three species of Leaf‐nosed bats (Hipposideridae)
    (2008-04) Mainoya, J. R.; Howell, Kim
    Histological studies were made of the median frontal sac from both male and female specimens of Hipposideros commersoni, H. ruber, and Triaenops persicus. In H. commersoni this organ which is more prominent in the male than in the female, con tained tri-lobed sebaceous glands associated with hair follicles and modestly enlarged simple saccular apocrine glands. On the other hand this structure in H. ruber con sisted entirely of a coiled-lobule type of apocrine gland. The female had only a rudi mentary gland without any sac. The complex frontal gland in T. persicus consisted of (1) a superficial haired layer containing sebaceous glands and saccular apocrine glands, (2) a deeper-lying enormously convoluted peculiar type of apocrine gland which was more active in males than females. The sexual dimorphism expressed in both the development and activity of the frontal gland in these Hipposiderid bats suggests possible important roles in the mediation of behavioural and physiological responses related to reproduction.RésuméDes analyses histologiques ont CtC effectuees sur la poche médiofrontale du mile et de la femelle de l'Hipposideros commersoni, de 1'H. ruber et du Triaenops persicus. Chez 1'H. commersoni cet organe, plus développé chez le mâle que chez la femelle, contenait trois glandes sébacées trilobCes en association avec des follicules capillaires et avec des glandes apocrines sacciformes quelque peu dilatées. Chez le H. ruber d'autre part, cette structure consistait uniquement en une glande apocrine en spirale et lobulée. La femelle ne possédait qu'une glande rudimentaire dépourvue de poche. Chez le T. persicus, la glande frontale, complexe, comportait: (1) une couche capillaire super-ficielle contenant des glandes sCbactes et des glandes apocrines sacciformes, (2) à un niveau plus profond, un type particulier de glande apocrine fortement convolutée, plus dans active chez le mile que chez la femelle. Ce dimorphisme sexuel qui se reflète tant dans le dCveloppement que dans I'activité de la glande frontale chez les Hipposiderid semblerait ainsi influer de faGon non négligeable sur le comportement et l'activité physiologique liés à la reproduction.
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    Histology of the neck ‘glandular’ skin patch in Eidolon helvum, Rousettus aegyptiacus and R. angolensis (Chiroptera: Pteropodidae)
    (2008-04) Mainoya, J. R.; Howell, Kim
    The histology of the neck ‘glandular’ skin patch has been examined in three Pteropodid bat species, Eidolon helvum. Rousettus aegyptiacus and R. angolensis. In E. helvum the neck skin patch contains a large sebaceous gland complex, which is better developed and more active in males than in females. A comparable area in R. aegyptiacus contains rather non-specialized sebaceous gland alveoli in association with hair follicles and which are more active in males than in females. In R. angolensis the brush-like hair of the neck skin patch is much longer and coarser in the male than in the female, but in neither sex was the skin patch glandular. On the basis of histological observations, the neck skin patch in E. helvum would appear to be important for scent emission while in R. aegyptiacus. the same structure would be less so. In R. angolensis, the neck skin patch, though covered by longer brush-like hair than in other species, contained almost no glandular tissue and perhaps functions to provide visual rather than olfactory behavioural cues. L'histologie des régions cervicales de peau ‘glandulaire’ a été examinée chez trois espèces de chauve-souris Ptéropodides (Eidolon helvum, Rousettus aegyptiacus et R. angolensis). Chez E. helvum, cette région contient une grande glande sébacée complexe mieux développée et plus active chez les mâles que chez les femelles. Chez R. aegyptiacus, cette même région contient des alvéoles d'une glande sébacée assez peu spécialisée, associées à des follicules pileux, qui est plus active chez les mâles que chez les femelles. Chez R. angolensis, la fourrure hérissée de la région cervicale est plus longue et plus raide chez le mâle que chez la femelle, mais la peau n'est glandulaire chez aucun des deux sexes. Sur la base d'observations histologiques, la région cervicale de la peau chez E. helvum semble responsable de l'émission d'odeur alors que chez R. aegyptiacus, la même structure l'est à un degré moindre. Chez R. angolensis, bien que couverte par des poils plus longs et hérissés que chez les autres espèces, la région cervicale de peau ne contient presque pas de tissu glandulaire et fonctionne peut-être pour fournir des indications comportementales plus visuelles qu'olfactives.