The Snakes of Osun Grove: a World Heritage Site in Osogbo, Nigeria

The Osun Grove, Osogbo, Nigeria, is a protected area covered by riparian forest, dry high forest and derived savanna. In January and June 2000 a total of 25 of snake species were recorded with Afronatrix anoscopus and Calabaria reinhardti being prominent. The incidence of Philothamnus semivariegatus, a savanna species, may be the result of the invasive savanna produced by farming activities around the grove. Nine species, led by A. anoscopus, accounted for 69.7 % of the snake community. The dominant species are either aquatic or terrestrial, with the exception of Boiga blandingi and Dendroaspis viridis that can be both arboreal and terrestrial, and C. reinhardti that is fossorial. Arboreal species mostly preyed on tree frogs and birds including eggs and nestlings, and the aquatic forms preyed on fish and frogs. Mammals, reptiles and toads constitute the prey items of terrestrial species while fossorial species feed on annelids, molluscs, arachnids, myriapods, hexapods, amphibians, reptiles and mammals. Rev. Biol. Trop. 55 (2): 717-721. Epub 2007 June, 29.

Se registró un total de 25 especies de serpientes en la arboleda de Osun en Osogbo, Nigeria, incluyendo prominentemente dos especies consideradas escasas en el sudoeste de Nigeria: Afronatrix anoscopus y Calabaria reinhardti; Philothamnus semivariegatus, una especie de la sabana, es común posiblemente debido a las actividades de cultivo fuera de la reserva. Junto con las ocho especies abundantes siguientes, A. anoscopus, representó el 69.7 % de la comunidad de serpientes. Las especies dominantes son acuáticas o terrestres, con excepción de Boiga blandingi y Dendroaspis viridis que son arborícolas y terrestres, y C. reinhardti que es fosorial. Las especies fosoriales tienen mayor diversidad trófica.

A twelve-month field study of the West African Thrush Turdus pelios (Passeriformes: Muscicapidae): Part 2: annual cycles

In Africa, birds inhabiting forested regions are less seasonal in their activities than those from open areas. In order to study annual cycles in forest regions of South western Nigeria, West African Thrushes (Turdus pelios ) were mist-netted and banded during the last two weeks of each month. The nest is a cup-shaped structure built out of grasses, herbs, weeds, roots and earth laid out in a clockwise manner. Only the nesting tree and feeding sites were defended during the breeding period. The clutch size was 2.69 ±0.20 eggs with a mean incubation period of 14.11 ±0.26 days. The mean nestling period was 15 ±1.00 days. The nestlings were fed on a variety of plant and animal matter, of which grass seeds and insects were predominant. Moult was found to be protracted with a population moult period of 194 days and a much shorter individual moult period. Moult and breeding periods were spread out: moult period dovetailed into the breeding period. The birds were found to gain weight during the period but they attained their maximum weight in August after the moult period. The lowest weight was recorded in February, during the peak of the dry season, when food availability was lower

El nido del tordo africano occidental es una estructura en forma de copa construida con pastos, hierbas, malezas, raíces y tierra, proyectado en el sentido de las manecillas del reloj. Solamente el árbol con el nido y los sitios de alimentación son defendidos durante la crianza. El tamaño de la nidada fue 2.69 ± 0.20 huevos con un periodo de incubación de 14.11 ± 0.26 días. El periodo promedio de cría fue de 15 ± 1.00 días. Los polluelos fueron alimentados con una variedad de material animal y vegetal, predominando las semillas de pasto y los insectos. La muda del plumaje alar es prolongada, con un período poblacional de muda de 194 días y un periodo individual mucho menor. La muda y crianza son tan prolongados que se empalman con el periodo de crianza. Las aves ganaron peso durante el periodo pero alcanzaron su peso máximo en agosto, después del periodo de muda. El peso más bajo fue el de febrero, lo que coincide con el pico de la estación seca, cuando los recursos alimenticios son escasos

A twelve-month field study of the West African Thrush Turdus pelios (Passeriformes: Muscicapidae). Part 1: food and feeding ecology

The feeding ecology of Turdus pelios was studied from field observations and gizzard contents. Quantitative data on feeding were obtained from repeated standard "fixed route "walks and observational points at seven sites from January to December 1998 on 5065ha at the Obafemi Awolowo University campus,Ile-Ife (7 º20 ’ N,4 º33 ’ E).Walks (each lasting about two hours)were started at various times of the day between 7.00 and 16.45 h.A total of 100 walks were made and binoculars were used to observe all feeding activities during 10 minutes at each site.Each feeding record included food type,method of feeding and reaction with con-specifics at feeding sites.Gizzards from mist-netted specimens were also studied.These birds fed most commonly twice a day between 06.00-9.30hr in the morning and between 17.00-18.30hr in the evening.Field observations showed that about 62%of the diet consisted of plant matter.The prey items were earthworms and terrestrial arthropods, of which orthopterans alone constituted 45%of the total.The prey size consumed by both sexes overlapped extensively:differences in prey size were significant only for spiders

Se examina la ecología alimenticia del ave Turdus pelios en Nigeria,África.Se observó que se alimenta frecuentemente dos veces al día entre 6:00 -9:30 am y entre las 17:00 -18:30 pm.Observaciones de campo mostraron que alrededor del 62%de la dieta consite en material vegetal. Las presas fueron lombices y artropodos terrestres,de los cuales los ortópteros constituyen el 45%del total.El tamaño de las presas consumidas por ambos sexos se traslapa ampliamente,y las diferencias fueron significativas solamente respecto al tamaño de las arañas (los machos consumieron más)