bluuebunny/crossref_metadata_2025_split huggingface dataset:
Notes on the population dynamics of the Kasungu elephants
Authors: JACHMANN H. 
Published: April 2008

SummaryPhotogrammetric methods were used to obtain data on the age structure of the separate groups of elephants in Kasungu National Park, Malawi, and of the population as a whole. The age structure is that of a young population with a high reproductive capacity. The mean calving interval between surviving calves is currently estimated as 3‐3 years, while the age at first conception is estimated as about 11‐0 years. The calving interval of the Kasungu elephant increases with the age of the cow. This phenomenon is either a difference between generations or occurs within the lifetime of a cow. In the latter case, changes in the age structure of the population of mature females result in a changing mean calving interval and hence changes in the reproductive rate.Mortality, estimated by three different methods, occurs at a mean annual rate of 8‐2%, There appears to be no significant difference from the mean annual recruitment rate of 9‐2%, suggesting a static population. Field observations indicate a short mating season from mid‐February to the end of March. Consideration is given to the possibility that creation of recruitment cycles in the age structure of the population under study, derived from equations describing the relationship between shoulder‐height and age, given by Laws et al. (1975), is due to differences in growth between East African elephant populations.RésuméOn a utilisé des méthodes photogrammétriques pour obtenir des données sur la structure d'âge de différents groupes d'éléphants au Parc National Kasungu au Malawi, ainsi que de l'ensemble de la population. Cette structure d'âge est celle d'une population jeune avec une capacité de reproduction élevée. L'intervalle moyen entre les naissances d'éléphanteaux survivants est estimé actuellement à 3 ans 1/3, alors que l'âge de la première conception est estiméà environ 11 ans. Au Kasungu, l'intervalle entre les mises‐bas augmente en fonction de l'âge de l'éléphante. Ce phénomène est soit une différence entre les générations, soit inhérent à la vie de tout éléphant femelle. Dans ce dernier cas, des changements dans la structure d'âge de la population des femelles adultes conduisent à un changement de l'intervalle moyen entre les mises‐bas et, par conséquent, du rythme de reproduction.La mortalité, estimée par trois méthodes différentes, se situe à un taux annuel moyen de 8,1/2%. Il ne semble pas y avoir de différence significative par rapport au taux annuel moyen de recrutement qui est de 9, 1/2%, ce qui suggère une population stable. Des observations sur le terrain montrent une courte saison d'accouplement allant de la mi‐février à la fin du mois de mars. On envisage la possibilité que l'apparition de cycles de recrutement dans la structure d'âge de la population étudiée serait due aux différences de croissance entre les populations d'éléphants d'Afrique Orientale, si l'on applque les équations données par Laws & al (1975) décrivant la relation entre l'âge de l'éléphant et la hauteur à l'épaule.
Unit flesh weights of some East African bovids
Authors: BLUMENSCHINE R. J. , CARO T. M. 
Published: April 2008

SummaryUnit flesh weights are provided for a sample of wild Thomson's gazelle, Grant's gazelle, impala and wildebeest. The data permit accurate estimates of the quantity of flesh consumed by modern carnivores and are useful for interpreting skeletal part profiles of archaeological bone assemblages. Despite relative constancy in the percentage of whole carcass flesh (about 50%), there exist differences in the distribution of flesh between sexes (neck v. pelvic‐lumbar regions) and among taxa (forelimb v. hindlimb), but apparently not among age classes.RésuméOn a calculé des unités de poids de chair dans un échantillon composé de gazelles de Thomson et de Grant, d'impalas et de gnous sauvages. Ces données permettent l'estimation de viande consommée par les carnivores actuels et sont utiles pour interpréter les profils squelettiques des assemblages osseux archéologiques. En dépit d'une constance relative dans le pourcentage de chair de la carcasse (environ 50%), il existe entre les sexes des différences dans la répartition de la chair (cou par rapport aux régions pelvique et lombaire) et entre les espèces (membres antérieurs par rapport aux membres postérieurs), mais apparemment pas entre les classes d'âge.
Insects and other invertebrate animals collected at high altitudes in the Ruwenzori and on Mount Kenya
Authors: SALT G. 
Published: April 2008

SummaryInvertebrate animals were collected at seven localities in the Ruwenzori range at altitudes between 12,500 ft and 15,500 ft (3810–4724 m); and at three localities on Mt. Kenya between 13,500 ft and 15,700 ft (4115–4785 m). Their habitats are briefly described, with special attention to the mosses present in them. The collections from the Ruwenzori contained 1514 specimens representing nineteen orders or higher groups and at least forty‐three families. They included sixty named genera, one new to science, and sixty named species, of which twenty‐five were new to science and one a new sub‐species. The collections from Mt. Kenya contained 126 specimens representing at least eighteen families. They included seventeen named genera, one new to science, and eighteen named species, of which eight were new to science. These collections add evidence in favour of the view that some groups of invertebrate animals, like some groups of vascular plants, have undergone insular evolution in the Afro‐alpine zone, and the represented on the different mountains in East Africa by vicarious species.RÉSUMEÉOn a récolté des invertébrés dans sept localitiés du massif du Ruwenzori à des altitudes de 38 10 à 4724 m et dans trois localités sur le mont Kenya entre 4115 et 4785 m. Leurs habitats sont brièvement décrits, avec une attention spéciale pour les mousses. Les collections du Ruwenzori contiennent 1514 spécimens représentant 19 ordres ou groupes supérieurs et au moins 43 familles. Elles comprennent 60 genres, dont un nouveau pour la science, et 60 espèces, dont 25 nouvelles pour la science et une nouvelle sous‐espèce. Les collections du Mont Kenya contiennent 126 spécimens représentant au moins 18 familles. Elles comprennent 17 genres dont un nouveau pour la science et 18 espèces dont 8 nouvelles pour la science. Ces collections plaident avec l'évidence en faveur de l'idée que certains groupes d'animaux invertébrés, de měme que certains groupes de plantes vasculaires, ont entrepris une évolution insulaire dans la zone afroalpine, et sont représentés dans différents massifs montagneux d'Afrique de l'Est par des espèces vicariantes.
Effects of Cubitermes testaceus (Williams) on some physical and chemical properties of soil in a grassland area of Uganda
Authors: OKWAKOL MARY J. N. 
Published: April 2008

SummaryThe physical and chemical properties of Cubitermes testaceus (Williams) mound and adjacent topsoils and subsoils were studied at Kaazi, southern Uganda, by collecting and analysing soil samples. Differences between clay and sand fractions of mound and non‐mound soil were slight. The colour of the mounds indicates that mound soil is derived from adjacent topsoil. Values for organic matter, total nitrogen, pH, calcium potassium and sodium of mound soil were significantly greater than those of adjacent topsoil, indicating that the termites altered the soil chemistry. Results obtained show clearly that Cubitermes testaceus significantly affect the chemical properties of soil but only slightly affect physical ones. It is suggested that the most significant effect of these termites on grassland soils in Uganda is the alteration in the quantity and distribution of organic matter and mineral nutrients.RÉSUMEÉLes propriétés physiques et chimiques des termitières de Cubitermes testaceus (Williams) et des sols superficiels adjacents ont étéétudiées a Kaazi, dans le sud de l'Uganda, par la collecte et l'analyse d'échantillons. Les différences entre les fractions argileuses et sableuses des sols de termitières et d'autres sols sont faibles. Les couleurs des termitières indiquent que le sol provient du sol superficiel adjacent. Les voleurs des matières organiques, nitrogène total, pH, calcium, potassium et sodium des termitières sont significativement supérieures que celles du sol superficiel adjacent, ce qui indique que les termites altèrent la composition chimique de celui‐cu, Les résultats obtenus prouvent clairement que Cubitermes testaceus affectent significativement les propriétés chimiques du sol, mais que les propriétés physiques ne sont que légèrement altèrèes. Il est suggéré que l'effet le plus significatif de ces termites sur les sols herbeux en Uganda est l'altération de la quantité et de la répartition de la matière organique et des nutriments minéraux.
Oviduct of the impala, Aepyceros melampus (Lichtenstein, 1812)
Authors: EPELU‐OPIO J. , KAYANJA F. I. B. , MUWAZI R. T. , MUWANGA G. M. , BUKENYA E. M. E. 
Published: April 2008

SummarySamples were taken from the ampulla and isthmus of the oviduct. Two cell types, ciliated and non‐ciliated, were identified as the principal constituents of the epithelium. The cell types exhibited different morphological and fine structural features. A few non‐ciliated cells possessed solitary kinocilia. Glycogen was not recognized in the epithelial cells. The epithelium showed reduction in height during pregnancy. There were cyclic alterations in the morphology and fine structure of the non‐ciliated cells but the ciliated cells appeared to be constant throughout the reproductive cycle. Two forms of secretory granules, prevalent during pro‐oestrus and oestrus, were recognized in the non‐ciliated cells.RÉSUMEÉDes échantillons furent prélevés dans les ampulla et isthmes de l'oviducte. Deux types de cellules, ciliées et non ciliées, furent identifiées comme les constituants principaux de l'épithélium. Les types cellulaires présentent différentes caractéristiques dans leur morphologie et leur structure fine. Quelques cellules non ciliées possèdent des kinocilia isolées. Le glycogène ne fut pas détecté dans les cellules épithéliales. L'épithélium présente une diminution de hauteur durant la gestation. On observe des altérations cycliques dans la morphologie et la structure fine des cellules non ciliées, mais celles des cellules ciliées paraissent constantes tout au long du cycle reproductif. Deux formes de granules secrétrices, reconnaissables durant les périodes de pro‐oestrus et d'oestrus, furent observées chez les cellules non ciliées.
Relationship between biomass of forage used and masses of faecal pellets of wild animals in meadows of the Dinder National Park
Authors: HASHIM I. M. 
Published: April 2008

SummaryMeadows in the Dinder National Park were used mostly by reedbuck (Redunca redunca cottoni W. Rothchild), buffalo (Syncerus caffer aequinoctialis Blyth), waterbuck (Kobus defassa harnieri Murie), roan antelope (Hippotragus equinus bakeri Heuglin), tiang (Damaliscus korrigum tiang Heuglin) and oribi (Ourebia ourebia montana Zimmerman). Use in the meadows was estimated by the clipping of green forage available for the wild animals. Their diet botanical composition was determined by microhistological analysis. In addition, masses of faecal pelletgroups voided in the meadows were determined at the end of the dry season. Microhistological analysis showed that wild animals were either grazers or mixed feeders. The grazers were reedbuck, buffalo, waterbuck and tiang, and the mixed feeders were roan antelope and oribi. There was a significant correlation between biomass of forage used and faecal masses voided for buffalo (r2= 0.41, P<0.06), buffalo and tiang (R2= 0.35, P<0.05), buffalo and waterbuck (R2= 0.93, P< 0.001) and waterbuck and tiang (R2= 0.31, P< 0.005) at various meadows of the park. The rate of forage use across the meadows, however, was high for the waterbuck compared to that for buffalo and tiang.RÉSUMEÉLes prairies du Parc National de Dinder sont exploitées principalement par le cobe des roseaux (Redunca redunca cottoni W. Rothschild), le buffle (Syncerus caffer aequinoctialis Blyth), le waterbuck (Kobus defassa harnieri Murie), l'antilope roanne (Hippotragus equinus bakeri Heuglin), le topi (Damaliscus korrigum tiang Heuglin) et l'oribi (Ourebia ourebia montana Zimmerman). Utilisation dans ces prairies fut estimée par la coupe de fourrage vert disponible aux animaux sauvages. La composition botanique de leur régime alimentaire fut déterminée par analyse microhistologique. De plus, des quantités de crottes laissées dans les prairies furent déterminées a la fin de la saison sèche. L'analyse microhistologique montre que les animaux sont soit brouteurs (‘grazers’), soit mixtes (‘mixed feeders’). Les ‘grazers’ sont le cobe des roseaux, le buffle, le waterbuck et le topi; les ‘mixed feeders’ sont l'antilope roanne et l'oribi. On constate une corrélation significative entre la bio‐masse du fourrage ingéré et les masse fécales abandonnées (r2= 0.41, P<0.06), le buffle et le topi (R2= 0.35, P<0.05), le buffle et le waterbuck (R2= 0.93, P<0.001) le waterbuck et le topi (R2= 0.37, P<0005) à différents pa&#x030c;turages du parc. Le taux d'utilisation de fourrage dans les pa&#x030c;turages est cependant plus élevé chez le waterbuck que chez le buffle ou le topi.
Host preference of oxpeckers in the Hwange National Park, Zimbabwe
Authors: HUSTLER K. 
Published: April 2008

SummaryYellowbilled oxpeckers Buphagus africanus and redbilled oxpeckers B. erythrorhynchus occur sympatrically in Hwange National Park. Two separate areas of the park were surveyed for oxpeckers and their host preferences. Yellowbilled oxpeckers preferred buffalo Syncerus caffer, black rhinoceros Diceros bicornis and white rhinoceros Ceratotherium simum, while redbilled oxpeckers preferred sable Hippotragusniger, giraffe Giraffa camelopardalis and kudu Tragelaphus strepsiceros. Differences in oxpecker numbers, host choice and niche expansion in the absence of certain hosts are discussed.RÉSUMEÉLe pique‐boeuf à bee jaune (Buphagus africanus) et le pique‐boeuf à bec rouge (B. erythrorhynchus) se rencontrent simultanément au P.N. Hwange. On a observé les deux espèces de pique‐boeuf et leurs h&#x006f;&#x030c;tes préférentiels dans deux régions séparées du pare. Le pique‐boeuf à bee jaune préfère le buffle (Syncerus caffer), le rhinocéros noir (Diceros bicornis) et le rhinocéros blanc (Ceratotherium simum), alors que le pique‐boeuf à bee rouge préfère l'antilope Sable (Hippotragus niger), la girafe (Giraff'a camelopardalis) et le Koudou (Tragelaphus strepsiceros). On discute des différences de nombre des pique‐boeuf, du choix de leur h&#x006f;&#x030c;te et de l'expansion de la niche écologique en l'absence de certains h&#x006f;&#x030c;tes.
Biomass dynamics of grassland vegetation in Kenya
Authors: BOUTTON THOMAS W. , TIESZEN LARRY L. , IMBAMBA SIMEON K. 
Published: April 2008

SummarySeasonal changes in plant biomass in the herb layer were measured at Nairobi National Park and Masai Mara Game Reserve in Kenya from January 1980 to February 1981. Plant biomass fluctuated in response to seasonal rainfall, and live biomass was correlated with rainfall and soil moisture at both locations. Peak values for live biomass at Nairobi National Park occurred at the end of the long rains during the June 1980 sample and ranged from 138 to 197gm‐2. Minimum values for live biomass at Nairobi occurred during a dry season in February 1981 and ranged from 8 to 39 g m‐2. The standing dead and litter compartments were larger than the live compartment during every sample period at Nairobi National Park, and together often comprised more than 80% of the total above‐ground biomass. Probably as a result of higher rainfall, peak values for live biomass at Masai Mara Game Reserve were higher than those at Nairobi. Again, peak biomass occurred during June following the long rains, and ranged from 218 to 294 gm‐2. Minimum values for live biomass occurred during February 1981, and ranged from 10 to 48 g m‐2. Standing dead and litter compartments were much smaller than at Nairobi National Park, reflecting more intense herbivore pressure and a greater frequency of fires at Masai Mara compared with that at Nairobi National Park.
Seasonal changes in the nutrient content of East African grassland vegetation
Authors: BOUTTON THOMAS W. , TIESZEN LARRY L. , IMBAMBA SIMEON K. 
Published: April 2008

SummarySignificant seasonal changes in the concentrations of N, P, K, and Ca were observed in the herb layer vegetation at Nairobi National Park and Masai Mara Game Reserve in Kenya. These changes were related to the alternation of wet and dry seasons. Live forbs typically had the highest concentrations of all nutrients, especially N and Ca, at both locations. Standing dead and litter compartments showed less seasonal variation and had the lowest concentrations of all nutrients except Ca when compared with those of other compartments. Standing stocks of all nutrients were higher at Nairobi National Park than at Masai Mara due to larger litter and standing dead compartments resulting from lower grazing intensity and a lower frequency of fire. Most of the aboveground nutrients at Nairobi National Park appeared to be recycled through the decomposer pathway, while a large proportion of the standing stock at Masai Mara appeared to be recycled through the excreta of large mammalian herbivores and through fires. The crude protein content of the live grass compartment fell below maintenance levels required for ruminants (5% crude protein) during September 1980 and February 1981 at Nairobi National Park and during June and July 1980 at Masai Mara Game Reserve. Thus, herbivore populations in these preserves may be limited by shortages of nutritionally adequate food during dry seasons, as previously reported for other regions in East Africa.
Age determination of the African buffalo, Syncerus coffer (Sparrman) in Zimbabwe
Authors: TAYLOR R. D. 
Published: April 2008

SummaryAge determination methods using teeth are described for African buffalo in Matusadona National Park, Kariba, Zimbabwe. Tooth eruption stages and age classes for sub‐adult animals were established by reference to a seasonal breeding peak and known dates of death. Teeth in adult animals were allocated age classes based on wear using measurements of crown height and by reference to previously published material. Layering in the dental cement indicated the deposition of one cementum line per annum and line counts were used to assign chronological ages to individual animals. Regressions of wear on age were confirmed by independent counts of cementum lines using a predictive wear model.
Age determination of the West African buffalo Syncerus caffer brachyceros and the constancy of tooth wear
Authors: AGE C. A. SPIN , BROWN W. A. B. 
Published: April 2008

SummaryMaxillae of 34 West African buffalo Syncerus caffer brachyceros were collected from three sites in Burkina Faso, West Africa, and age determined from tooth appearance and the enamel height of M1 according to the criteria of Grimsdell (1973) for Ugandan buffalo Syncerus caffer caffer. Good agreement between the two methods was found. Ground and decalcified sections were prepared from M1 and the interradicular cementum lines counted. Although this gave inconsistent results in terms of assumed age compared with the other two methods, it is concluded that agreement was sufficiently close to suggest that the rate of attrition with age was similar in both populations.
Wildebeest migration in the Kalahari
Authors: WILLIAMSON D. , WILLIAMSON J. , NGWAMOTSOKO K. T. 
Published: April 2008

SummaryBetween April 1981 and December 1984 aerial surveys were conducted in the northern Central Kalahari Game Reserve, the Lake Xau area and a larger area in southwestern Botswana. Range conditions were monitored in the northern Central Kalah, ri Game Reserve. The migration of wildebeest to surface water at Lake Xau was documented. Since the Kalahari wildebeest population has had severely restricted access to surface water for decades and this access is steadily diminishing, it is inferred that the existing population is smaller than it used to be and can be expected to decline further in the future.
Small mammals of the Bale Mountains, Ethiopia
Authors: YALDEN D. W. 
Published: April 2008

SummaryA sample of 535 small mammals, caught over a range of altitudes from 1500 to 4000 m in the Bale Mountains, on various expeditions from December 1971 to August 1986, enables the altitudinal zonation of the species to be delimited. The most abundant species, Lophuromys flavopunctatus, ranged from near the lower tree line at 1550 m, right up through the forested zones and onto the Afro‐alpine moorland at 3900 m. The endemic Praomys albipes also ranged through the forest from 1550 to 3200 m, but was replaced in open habitats between 2400 and 3900 m by Stenocephalemys griseicauda and between 3000 and 4000 m by S. albocaudata, which was relatively more abundant than its congener at higher altitudes. Other moorland species, including Crocidura fumosa, Otomys typus, Lophuromys melanonyx and Arvicanthis blicki were also commonest at 3800–4000 m, but, like the Stenocephalemys spp., penetrated to lower altitudes in open habitats. Mus mahomet was confined to lower altitudes (1510–3000 m) and open habitats, apparently replaced by Mus triton, not previously recorded from Ethiopia, in forested habitats at middle altitudes (1950–2400 m).
Further evidence of exogenous processes regulating the population of zebra in the Serengeti
Authors: SENZOTA R. B. M. 
Published: April 2008

SummaryBetween 1970 and 1980 the population size of the migratory zebra in the Serengeti remained constant. During the same period the population of wildebeest, also a large migratory ungulate, increased in a manner compatible with existing ecological theories. Sinclair & Norton‐Griffiths (1982) have produced evidence to suggest that predation pressure was the factor that prevented the zebra population from increasing. This paper presents further evidence, based on population structure, which shows that the size of zebra population should have increased.RÉSUMEÉEntre 1970 et 1980, la population de zèbres migrateurs du Serengeti est demeurée constante. Pendant le měme période, la population de gnous, autre grand ongulé migrateur, a augmenté d'une manière compatible avec les théories écologiques existantes. Sinclair et Norton‐Griffiths (1982) ont présenté des éléments suggérant que la pression des prédateurs était le facteur qui empèche la population de zèbres de s'accroi&#x030c;tre. J'apporte la preuve, basée sur la structure de la population, qui montre que le population de zèbres aurait augmenté.