Spatial-temporal variation in sex ratio and group size of ostriches (Struthio namelus) in the Serengeti National Park and environs in Northern Tanzania

A study was conducted on variation in sex ratio and group size of ostriches (Struthio camelus) in Serengeti National Park and adjacent partially protected areas in northern Tanzania. Data were collected for two years (2005- 2006), along 388 km of roads. The two areas were compared with respect to ostrich sex ratio (male: female) and group size. Seasonal variation of these variables (sex ratio and group size) was also determined. Repetitive sampling showed an overall femaleskewed sex ratio, which was significantly different from unity. The sex ratio inside the National Park was also significantly skewed towards females, whereas that in the partially protected areas was skewed in favour of the males. There was a significant difference in sex ratios between the two areas (Chi square: !2 = 48.041, DF = 2, p<0.001). The grand median group size was 3 birds and the same median group size was obtained both in the National Park and partially protected areas, and there was no significant difference in group sizes between the areas (Median test: !2 = 1.861, DF = 1, p = 0.173) although bigger groups were observed in the park than in the partially protected areas. In addition, there was a tendency for ostriches to form significantly larger groups in the wet season than dry season in both areas (p<0.05). Natural predators of ostrich were found to be significantly higher inside the National Park than outside it (p<0.05). The presence of natural predators and seasonal variations may have influenced the present results.Keywords: group size – ostrich – Serengeti – sex ratio – Struthio camelu

Variation of small mammal populations across different habitat types in the Serengeti ecosystem

This study investigated the abundance and diversity of small mammals in cultivated land (unprotected area) and wooded grassland in the Serengeti National Park (protected area) in the Serengeti ecosystem. Small mammal populations were sampled through capture-mark-recapture trapping techniques in March-April 2010. A total of 896 trap nights covering wet season, 9 species of rodents and 1 species of soricomorphs (shrew family) were captured. Overall, Multimammate rat Mastomys natalensis (Smith) was by far the most abundant rodent in cultivated land (28%) while inside the park, shrew Crocidura sp., was high in numbers (8%). A significantly higher abundance (trap success) of small mammals was obtained in the cultivated area compared to the national park (p < 0.01). There was also a significant difference in the two diversity indices between the cultivated areas (Hꞌ = 0.84) and national park (Hꞌ= 0.57) (p < 0.01).  The differences are probably habitat related i.e. types of crops cultivated in agricultural fields that might have attracted small mammals. There was moderately high similarity in the number of species caught in the two sites (Sørensen Coefficient (CCs) = 0.57), indicating that species composition did not vary significantly between the two sites with different conservation status. Overall high abundance and diversity in the cultivated areas may have resulted from the availability of food materials to granivorous small mammals which were majority.  This high abundance and diversity  outside the national park raises doubt as to whether the protected areas can still be considered as the most feasible approach of ensuring small mammals protection.Keywords: agriculture, habitat, small mammals, Serenget

Traditional medicinal uses of small mammal products: a case study of the African savannah hares, crested porcupines and rock hyraxes in Serengeti District, Tanzania

Traditional medicines, both plant and animal products, have been used to cure various diseases since time immemorial especially in rural areas worldwide. Many studies have focused on traditional plant products, but little research has been conducted on animal traditional medicines. This study investigated the use of small mammal products for medicinal purposes in three villages bordering Serengeti National Park in Serengeti District, Tanzania. A total of 71 respondents were interviewed in Kisangura, Nyamburi and Machochwe villages in November 2010, using questionnaires. Villagers hunted small mammals mainly by dogs for cultural and ornamental reasons. Products of African savannah hare (Lepus microtis), crested porcupine (Hystrix cristata) and rock hyrax (Procaviacapensis), were the most commonly used materials for believably curing nearly 11 different ailments including stomach pain, diarrhoea, convulsions and bleeding nose. Use of traditional medicines from these animals was significantly higher than other uses combined (p < 0.001), indicating that these small mammal products are important alternative medicinal products. However, although the small mammals utilised for medicinal purposes in the study area are categorised as Least Concerned (LC) presence and utilization of rare or threatened species in the same area cannot be ruled out. Therefore sustainable utilization of small mammals needs to be advocated.Keywords: Traditional medicine, small mammal, Serengeti Ecosystem, Tanzani

Group-size effect on scanning behaviour of Maasai Ostrich Struthio camelus massaicus

Scanning behaviour enables birds to collect information important for their survival, such as detecting predators (anti-predatory strategy) and searching for food. The scanning behaviour of the Common Ostrich Struthio camelus was investigated by determining the scanning duration (total seconds during 5-min periods that a bird’s head was raised) and scanning rate (number of times an individual raised its head per minute) among different group sizes in late 2006 in Serengeti National Park, Tanzania. A total of 14 males and 20 females were observed. Scanning duration was a function of group size where individuals in small groups scanned for longer times than individuals in large groups. However, increasing group size did not have a significant effect on the scanning rate among the groups. Individual vigilance among ostriches is influenced by group size, whereas individual scanning rate may be influenced by factors other than group size, such as body size and habitat type. Higher scanning duration in small groups is attributed to anti-predatory behaviour

The influence of agricultural activities on the diversity of rodents in Kindoroko forest reserve and surrounding areas, North Pare Mountains, Tanzania

The patterns of richness, diversity and similarity in rodent communities in agricultural areas and in adjacent Kindoroko Forest Reserve in the North Pare Mountains, Tanzania were assessed. By using a capture-mark-recapture method, 289 individuals of nine rodent species in March and May 2011 were captured. Seven species were recorded in agricultural area and 5 species in the Forest Reserve. Multimammate Rat (Mastomys natalensis) was abundant in agricultural area while soft-furred mouse (Praomys delectorum) was dominant in the Forest Reserve. Species diversity was greater outside than inside the forest, supporting results of earlier studies. Species similarity between the two habitats was high indicating that the species were generally evenly distributed across the landscape. The results showed the importance of agricultural land to the rodent community. Differences in rodent diversity between the two areas could be attributed to the availability of food and the heterogeneous environment in agricultural areas. While the factors causing lower diversity in the Forest Reserve are not yet understood, reduced food availability and competition with herbivores could be a contributing factor. Further work to understand the factors determining habitat preferences of species for conservation and ecosystem function is recommended.Keywords: Diversity, Kindoroko, North Pare Mountains, Rodents, Tanzani

A Comparative Study of Species Diversity of Migrant Birds Between Protected and Unprotected Areas of the Hadejia-Nguru Wetlands, Nigeria

Among the most complex and fascinating behaviour in birds is their long, non-stop migration. Despite Hadejia-Nguru Wetlands (Ramsar site) being an important wintering ground for migratory birds, little is known about the diversity while density is completely lacking. This study assessed the status of migratory birds in the wetland’s Protected Areas (PAs) and Unprotected Areas (UPAs). A total of 99 census points spaced 400 m apart with radius of 100 m were surveyed from 14 wetlands (48 point count stations in the PAs and 51 in the UPAs). A total of 54 migrant bird species belonging to 13 orders and 25 families were recorded. Of the 54 species, 20 were Intra-African migrants and 34 Palearctic winters including two globally threatened species; the European Turtle Dove Streptopelia turtur and Pallid Harrier Circus macrourus. Results showed that Protected wetlands had significantly higher species diversity (H' = 1.39) than Unprotected ones (H' = 1.28) (p = 0.0064), however, there was no significant difference in the density of birds between the two areas (p = 0.9246). The two areas were similar in species composition by 81%. Both Palearctic and Intra-Africa migrant birds were recorded in the wetland, thus revealing the importance of the Hadejia-Nguru as wintering sites for migratory birds. The Nigerian government has obligation to protect these migratory birds because it is a signatory to several international treaties aimed at conserving these birds. Key words: Circus macrourus, Hadejia-Nguru Wetlands, Threats to migratory birds, Palearctic and Intra-Africa Migrant birds, Streptopelia turtu

Analyzing the building blocks of resilience: Findings from a baseline survey of the Tuungane Population, Health, and Environment Project in western Tanzania

Although the value of population, health, environment (PHE) programs is appreciated by the development community and the conceptual linkages they incorporate are sound, little evidence exists to demonstrate their short- and long-term impacts—particularly the role that the family planning (FP) component of PHE projects plays in building resilience, improving livelihoods, and helping people adapt to climate change. To contribute to filling this gap, the Evidence Project collaborated with Tuungane, a PHE project jointly implemented by The Nature Conservancy and Pathfinder International, to conduct further analysis of their existing data and examine the evidence base around integrated PHE programming, FP, climate change adaptation, and resilience. This paper analyzes data from the Tuungane Project baseline survey to show the pre-project level of knowledge and attitudes among village residents regarding their understanding and use of FP. We hope to use this analysis to inform future efforts that will look more deeply at the relationships among and between: FP and climate change adaptation, FP and resilience, and the pathways through which the FP and other components of PHE projects like Tuungane contribute to building resilience and enhancing the ability to adapt to climate change

Using social network analysis of mixed-species groups in African savanna herbivores to assess how community structure responds to environmental change

The dynamics of wildlife populations often depend heavily on interspecific interactions and understanding the underlying principles can be an important step in designing conservation strategies. Behavioural ecological studies can here provide useful insights into the structure and function of communities and their likely response to environmental changes. In this study of the Masai Mara herbivore community, we use a social network approach to investigate social affinities between species and how these change over the year in response to seasonal changes in ecological conditions. We find that even though social networks were correlated across different ecological conditions, for half the species dyads in the community, the strength of social affinities responded to changes in rainfall and/or the presence of migratory wildebeest. Several species consequentially adopted more or less central positions in the network depending on ecological conditions. The findings point out interspecific social links that are likely to be attenuated or strengthened as a consequence of human-induced environmental changes, and therefore call for particular attention of conservation managers. The eco-evolutionary ramifications of the perturbations of social affinities still require further stud

Background matching in the brown shrimp Crangon crangon : adaptive camouflage and behavioural-plasticity

A combination of burrowing behaviour and very efficient background matching makes the brown shrimp Crangon crangon almost invisible to potential predators and preys. This raises questions on how shrimp succeed in concealing themselves in the heterogeneous and dynamic estuarine habitats they inhabit and what type of environmental variables and behavioural factors affect their colour change abilities. Using a series of behavioural experiments, we show that the brown shrimp is capable of repeated fast colour adaptations (20% change in dark pigment cover within one hour) and that its background matching ability is mainly influenced by illumination and sediment colour. Novel insights are provided on the occurrence of non-adaptive (possibly stress) responses to background changes after long-time exposure to a constant background colour or during unfavourable conditions for burying. Shrimp showed high levels of intra- and inter-individual variation, demonstrating a complex balance between behavioural-plasticity and environmental adaptation. As such, the study of crustacean colour changes represents a valuable opportunity to investigate colour adaptations in dynamic habitats and can help us to identify the mayor environmental and behavioural factors influencing the evolution of animal background matching