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Sustainable use and management of resources require regular monitoring. In the case of animals, their numbers and distributions are important in determining future trends. The data can also be used for planning and management needs such as habitat use and design of park boundaries (Norton-Griffiths, 1978). Aerial surveys in East Africa have collected data on animal numbers and other environmental parameters coinciding with wet, intermediate and dry seasons and hence determining animal movements in relation to their food supply (Western, 1975; Norton-Griffiths, 1978; Sinclair & Norton-Griffiths, 1979). Population trends of animals and their food supply has a bearing on their sustained management in an ecosystem as noted by Kalikawe & Kgathi (1993), Lamprey (1984), Kahurananga (1981), Western (1973) among others. The Department of Resource Surveys and Remote Sensing has been conducting aerial surveys in Ewaso Nyiro basin since 1977 and the cardinal objective of this paper is to present and explain an analysis of animal population trends in this basin spanning a period of 20 years, which is invaluable to the sustainable management of the basin’s biodiversity. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wild meat has long been used as a source of food and income by many communities across the tropics (Ingram et al., 2021). I Awareness raising activity i : These activities typically provide information to local communities or urban consumers regarding the impacts of unsustainable wild meat hunting, the laws pertaining to wild meat use and different options for wild meat management. A selection of publicly accessible databases and the websites of major conservation NGOs and donors (including the World Wide Fund for Nature (WWF), the Wildlife Conservation Society (WCS), the Rufford Foundation and the Global Environment Facility) were searched using keywords ("wild meat"; "wildmeat"; "bushmeat"; "bush meat"; "viande de brousse") to identify wild meat management projects active between 2000 and 2021 in Central Africa (Appendix 1). [Extracted from the article]

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper addresses the effect of human activities on the density of large mammals in the Dzanga-Ndoki National Park and the adjacent Dzanga-Sangha Reserve in the Central African Republic. Between six and eight 20 km long permanent transects were walked on a monthly basis from January 1997 to August 1999 to assess large mammal populations as well as human intrusion. There were no obvious seasonal or monthly trends in elephant, gorilla or non-human primate densities. Overall, it appears that human activities negatively influence the distribution of most of the large forest animals in Dzanga-Sangha. Elephants in particular were significantly less common in areas used by humans, but also other species such as non-human primates showed lower densities closer to the main road and the town of Bayanga. This study confirms the findings of previous studies that roads have a negative impact on wildlife populations. Results of this study stress the need for conservation of large uninterrupted forest blocks to maintain wildlife populations at normal levels. Simply creating roads, even within a protected Central African forest, is likely to have negative impacts on wildlife populations. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article focuses on the findings of an analysis of morphological variation in metriaclima melabranchion, a cichlid found along the shore of Lake Malawi. Significant morphological separation was found, characterized mostly by eye diameter differences between the two population subsets of the cichlid, separated by 20-m depth. A positive relationship between eye size and transmission spectrum width in some of the Lake's cichlids was also found. Along with eye diameter, cheek depth was smaller at the deeper location.

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The paper gives evidence that the vocal activity of elephants varies with group size, composition and reproductive status, and that elephants' calling patterns could therefore provide the basis for a remote monitoring system. We examined a 3-week set of array-based audio recordings of savanna elephants (Loxodonta africana ), searching for diagnostic acoustic parameters. An acoustic array made it possible to locate recorded sounds and attribute the calls to particular elephants or elephant groups. Simultaneous video recordings made it possible to document visible behaviour and roughly correlate it with vocalizations. We compared several measures of call density in elephant groups containing up to 59 individuals, and found that rates of calling increased with increasing numbers of elephants. We divided all call events into three structural types (single-voice low-frequency calls, multiple-voice clustered low-frequency calls, and single-voice high frequency calls), and found that the incidence of these varies predictably with group composition. These results suggest the value of a network of listening systems in remote areas for the collection of information on elephant abundance and population structure. [ABSTRACT FROM AUTHOR]

We studied the social system and time budget of kob antelopes in the Comoé National Park, Côte d'Ivoire from March 1993 till May 1998, a population that is suffering from heavy over-hunting, to assess information about the effects of population decrease and its relevance for conservation of this antelope population. Single animals accounted for the majority of observed kob antelopes. Time allocated to certain behavioural traits depended on group size, with animals in smaller units spending less time on behaviours sensitive to predation risk. Single animals allocated far less time to ruminating and feeding being more vigilant and walking more. Groups were highly fluid and associations between individuals could be predicted by home-range overlap among females but not for female/male associations where association indices might be influenced by reproductive aims. Frequency of social groupings did not change compared with earlier studies when population density was much higher. However, compared with these studies maximum group size decreased, and smaller groups became more abundant. The observed effect of group size on the time budget of kob antelopes in combination with a steady decrease in group size because of reduction in population size might have a severe impact on the long-term persistence of the studied kob population due to anticipated aggravated predation effects. As males form the majority of single animals, putting them on higher predation risk, number of males decreases more rapidly than the number of females, which might eventually lead to a collapse of the kob population. Résumé Nous avons étudié le système social et l'emploi du temps des antilopes cobes dans le Parc National de Comoé, en Côte d'Ivoire, entre mars 1993 et mai 1995. C'est une population qui souffre d'une grave sur-chasse, et nous voulions évaluer les informations sur les effets de la diminution de la population et leur pertinence par rapport à la conservation de cette population d'antilopes. La majorité des observations de cobes concernaient des animaux solitaires. Le temps consacréà différents types de comportement dépendait de la taille du groupe, les animaux faisant partie des plus petits groupes allouant moins de temps à des comportements sensibles au risque de prédation. Les animaux isolés passaient beaucoup moins de temps à ruminer et à se nourrir car ils étaient plus vigilants et se déplaçaient davantage. Les groupes étaient très fluides, et on pouvait prévoir les associations entre individus femelles par le recouvrement de l'occupation spatiale des femelles, mais pour les associations mâles-femelles, les indices peuvent être influencés par des buts reproducteurs. La fréquence des regroupements sociaux n'a pas changé par rapport aux études antérieures, quand la densité de la population était beaucoup plus élevée. Cependant, par rapport à ces études, la taille maximale du groupe a diminué, et les plus petits groupes sont plus abondants. L'effet observé de la taille du groupe sur le budget temporel des antilopes cobes, combinéà la diminution très nette de la taille des groupes due à la réduction de la taille de la population, pourrait avoir un impact sévère sur la persistance à long terme de la population étudiée car on peut s'attendre à des effets plus graves de la prédation. Comme les mâles forment la majorité des individus solitaires, ce qui les met plus en danger face aux prédateurs, le nombre de mâles diminue plus vite que celui des femelles, ce qui pourrait conduire à l'effondrement de la population de cobes. [ABSTRACT FROM AUTHOR]

A capture-mark-recapture study was conducted in crop fields in Morogoro, Tanzania, to investigate how the population dynamics of multimammate field rats, Mastomys natalensis, was influenced by the commonly practised land preparation methods and cropping systems. Two land preparation methods (tractor ploughing and slash and burn) and two cropping systems (mono-cropping with maize and inter-cropping with maize and beans) were investigated in a Complete Randomized Design experiment with 2 × 2 factors, and two 0.5 ha replicates per treatment. Mastomys natalensis comprised 97.8% of the abundance of the three rodent species captured in the study area. The slash and burned fields had higher rodent population densities than tractor ploughed fields ( P < 0.05)... [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Antelopes are prominent wildlife in Waza National Park, situated in Sahelo-Sudanian Cameroon, which has witnessed dramatic changes in rainfall and flooding. To assess their impacts, we reviewed 26 aerial and terrestrial surveys, comprising total, transect and localized counts. Estimated numbers of kob using the floodplain throughout the dry season, dropped from 20,000 in the 1960s and 1970s to 2000 in the mid-1980s. They recovered to 5000 in the mid-1990s but not further despite increased flooding. Estimated numbers of korrigum and roan using the floodplain later in the dry season, dropped in the early 1970s and only slightly recovered in the 1990s. The diversity of counting methods notwithstanding, the drop in kob numbers and the disappearance of waterbuck can be attributed to the construction of the Maga dam upstream in 1979 and subsequent low rainfall. The kob population structure suggests that its reproduction capacity was, however, not hit. Antelope–livestock contacts, provoking the transmission of diseases such rinderpest during droughts, explain better the dramatic drops in population numbers than poaching, which is likely to have remained rather constant. The effects of rainfall, flooding and human interventions on antelope populations increasingly appear to be interacting. Résumé Les antilopes constituent la faune principale du Parc National de Waza qui, situé dans la partie sahélo-soudanienne du Cameroun, a connu des changements spectaculaires de pluviosité et d'inondation. Pour évaluer leurs impacts, nous avons passé en revue 26 opérations de surveillance aériennes et terrestres, comprenant des comptages totaux, par transects et locaux. Les estimations du nombre de cobes, qui fréquentent la plaine inondable pendant toute la saison sèche, sont passées de 20.000, dans les années 1960 et 1970, à 2 000 au milieu des années 1980. Ils sont revenus vers 5 000 au milieu des années 1990, mais pas davantage, malgré des inondations en augmentation. Les estimations de korrigums et de rouannes qui fréquentent la plaine inondable plus tard en saison sèche avaient déjà diminué au début des années 1970 et n'ont que légèrement remonté dans les années 1990. Même si les méthodes de comptages furent diverses, la chute du nombre de cobes et la disparition des waterbucks peuvent être attribuées à la construction en 1979, en amont, du barrage de Maga et aux faibles chutes de pluies qui ont suivi. La structure de la population de cobes suggère que sa capacité de reproduction n'a pourtant pas été touchée. Les contacts entre antilopes et bétail, qui ont entraîné la transmission de maladies comme la peste bovine pendant les sécheresses, expliquent plus sûrement le déclin dramatique des populations que le braconnage qui est probablement resté assez constant. Les effets des chutes de pluie, des inondations et des interventions humaines sur les populations d'antilopes semblent interagir de plus en plus. [ABSTRACT FROM AUTHOR]

The Namib Desert golden mole ( Eremitalpa granti namibensis) is morphologically, physiologically and behaviourally specialized for living in the harsh loose-sand desert. Ecological studies have relied on visually tracking animals on the surface of sand dunes. A radio tag would allow individuals to be more reliably located, even while under the sand. We developed a radio attachment and gathered preliminary data on winter habitat use by six individuals during 21 days. We compare data from previous studies and suggest that the greater diurnal activity, smaller home ranges, and more restricted movement patterns that we found are related to the unusual thermal and metabolic biology of Eremitalpa. Résumé La taupe dorée du Désert du Namib ( Eremitalpa granti namibensis) est morphologiquement, physiologiquement et comportementalement spécialisée pour vivre dans le rude désert de sable fin. Des études écologiques se sont basées sur l'observation visuelle des animaux à la surface des dunes de sable. Un marquage radio permettrait de localiser plus exactement les individus même sous la surface. Nous avons développé un dispositif radio et nous avons réuni des données préliminaires sur l'utilisation hivernale de l'habitat par six individus pendant 21 jours. Nous comparons les données d’études précédentes et nous suggérons que la plus grande activité diurne, les plus petits espaces vitaux et les schémas de déplacements plus restreints que nous avons relevés sont liés à la biologie thermique et métabolique inhabituelle d’ Eremitalpa. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Examines the impact of predation on survival rate and population density of hingeback tortoise Kinixys spekii in the Sengwa Wildlife Research Area, Zimbabwe. Probability of capture; Abundance of predators; Variation in sexual size dimorphism; Rate of juvenile growth; Frequency distribution of age at death; Measure of population density and mortality area.

Illustrates the benefits of combining statistical methods with geographical information system techniques to increase insight into wildlife population dynamics in Laikipia district, Kenya. Estimates of population parameter; Comparison between the random and systematic sampling designs used in wildlife aerial surveys; Differences in distance between groups of animals.

Describes the fluctuation and social structure of the elephant population of Samburu and Buffalo Springs National Reserves, Kenya. Indication of a female biased population sex ratio; Analysis of family unit size; Induction of elephant migrations; Effect of poaching on the population; Response to seasonal variations in range use; Bimodial distribution of family unit presence.

Summary: The population dynamics of Mus minutoides and Steatomys pratensis are virtually unknown. These two species were live-trapped over a 12-month period in a subtropical grassland in Swaziland. Numbers of M. minutoides were relatively high in winter, declined in spring and the population disappeared in summer and autumn. By contrast, numbers of S. pratensis increased gradually from winter to summer and reached a peak in autumn. There were no differences between the mean weights of male and female M. minutoides and S. pratensis. There were, however, seasonal differences in the mean weight of male S. pratensis, with highest weights recorded in summer. Individuals of both species came into breeding condition in spring (October–November). Reproduction had ceased by the end of autumn (April–May). Monthly survival rates of M. minutoides were highest in winter, but did not vary seasonally in S. pratensis. Burning had a pronounced effect on the distribution of S. pratensis. Steatomys pratensis individuals selected recently burnt but revegetated areas over unburnt areas. The effect of burning on the M. minutoides population is difficult to assess, as this species disappeared shortly after the fire. [ABSTRACT FROM AUTHOR]

The article presents a discussion on the widespread depletion of African mammal populations. It has been long understood by conservationists that wildlife populations in African parks and reserves are highly dependent on conditions prevailing in surrounding areas. It is stated that if local people consider wildlife valuable and worth conserving, it will have an ample chance of surviving, otherwise it will disappear. To safeguard wildlife, protected areas alone are insufficient, and declines inside parks are examples of trends operating in broader landscapes.

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)