Mwangi Githiru

National Museums of Kenya · Department of Zoology

Mt. Kasigau is the northeastern most of the Eastern Arc Mountains global hotspot and harbours some endemic and threatened species, but little is known about bird community changes along its elevational gradient. We assessed the relationship between bird biodiversity metrics, season, human disturbance, elevation and temperature using mist-netting da...

Risk assessment relies on cost–benefit analysis by prey species in relation to predator behavior. The lunar cycle can have strong influences on the way that predator and prey species behave in their environment as light levels can influence activity patterns. By examining how lunar phase influences behavior, we may be able to better predict instanc...

Dissertation findings synopsis

Farmers in sub-Saharan Africa are facing threats to their livelihoods including climate change, unsustainable farming practices, increasing water scarcity, and crop raiding herbivores, among other challenges. How demographic, economic, and social factors impact farmers’ attitudes and responses to such threats and the relationship to conservation in...

Land-use change remains the main threat to tropical forests and their dependent fauna and flora, and degradation of existing forest remnants will further accelerate species loss. Forest degradation may result directly from human forest use or through spatial effects of land-use change. Understanding the drivers of forest degradation and its effects...

Keywords: additive strategy cooperative breeding egg size feeding rate load-lightening strategy placid greenbul social factor tropical forest Females are predicted to adjust their reproductive investment to optimize the trade-off between current and future reproduction. In many cooperatively breeding birds, females have been shown to reduce their i...

Unsustainable hunting, both illegal and legal, has led to the extirpation of many species. In the last 35 years giraffe Giraffa spp. populations have declined precipitously, with extinctions documented in seven African countries. Amongst the various reasons for these population declines, poaching is believed to play an important role in some areas....

In cooperatively breeding species, group members may derive multiple benefits from helping to raise other individuals’ offspring, yet not all individuals do so. In this study, we tested predictions from the “kin selection”, “pay-to-stay”, “group augmentation” and “skills” hypotheses, to explain why group members feed nestlings of breeding placid gr...

Negative interactions between humans and wildlife (i.e. those presenting risks to human security or private property) can trigger retaliation and potential human-wildlife conflict (HWC). The nature and strength of these human responses may depend on previous interactions with wildlife and can be shaped by landscape conditions. However, the ways in...

Kasaine metal strip fences have been found to be one effective method to mitigate African elephant crop raiding. We have been conducting trials at our study site in the Kasigau Widlife Corridor of Kenya since 2017 on a variety of fences. Preliminary results are reported in our 2020 African Journal of Ecology article, and our studies continue. The m...

It remains poorly understood how effects of anthropogenic activity, such as large-scale habitat fragmentation, impact sociality in animals. In cooperatively breeding species, groups are mostly formed through delayed offspring dispersal, and habitat fragmentation can affect this process in two opposite directions. Increased habitat isolation may inc...

It remains poorly understood how effects of anthropogenic activity, such as large-scale habitat fragmentation, impact sociality in animals. In cooperatively breeding species, groups are mostly formed through delayed offspring dispersal, and habitat fragmentation can affect this process in two opposite directions. Increased habitat isolation may inc...

Socially monogamous females regularly mate with males outside the pair bond. The prevailing explanation for this behavior is that females gain genetic benefits resulting from increased fitness of extra-pair offspring. Furthermore, because of the risk of reduced paternal care in response to cuckoldry, females are expected to seek extra-pair copulati...

Protected areas are considered the cornerstone of biodiversity conservation, but face multiple problems in delivering this core objective. The growing trend of framing biodiversity and protected area values in terms of ecosystem services and human well-being may not always lead to biodiversity conservation. Although globalization is often spoken ab...

Human activities impact upon natural habitats used by birds for breeding and foraging, and lead to changes in the composition and spatial distribution of predator communities, mainly through loss, fragmentation and disturbance of formerly pristine habitat. Yet possible fitness consequences of such changes through impacts on bird nest‐site selection...

Citizen science is gaining increasing prominence as a tool for science and engagement. However, despite being a potentially valuable tool for sustainable development, citizen science has little visibility in many developing countries. We undertook a collaborative prioritisation process with experts in conservation and the environment to assess the...

The two major conservation issues for drylands of Africa are habitat loss or degradation and habitat fragmentation, largely from agriculture, charcoal production, and infrastructural development. A key question for management is how these landscapes can retain their critical ecological functions and services, while simultaneously supporting resilie...

The African elephant, Loxodonta africana, is under threat from habitat loss, poaching and human–elephant conflict. To mitigate for impact of habitat loss and reduce conflict, connectivity between elephant habitats can be improved through the protection of corridor areas. This study looks at elephant distribution and movement patterns within the Kas...

For avian group living to be evolutionary stable, multiple fitness benefits are expected. Yet, the difficulty of tracking fledglings, and thus estimating their survival rates, limits our knowledge on how such benefits may manifest postfledging. We radio-tagged breeding females of the Afrotropical cooperatively breeding Placid greenbul (Phyllastreph...

Since the 1970s, the globally endangered Grevy's zebra Equus grevyi has suffered a substantial reduction in range and population size. Grevy's zebra was introduced into the Tsavo ecosystem in two translocations: 22 individuals released in Tsavo East National Park in 1964 and 30 individuals released in Tsavo West National Park in 1977. This study fo...

Most studies on tropical conservation questions are conducted by researchers of developed countries from the north. This geographic disconnection was recently criticised by Mammides et al. Here, we reflect on their findings and add further views from scientist’s and journal editor’s perspectives. We argue that journals are, a priori, most strongly...

Chomba et al. recently examined at how present day actions can reinforce or aggravate historical injustices around land, and what should be done about it. The authors looked at the benefit distribution policy and practice of the Kasigau Corridor REDD+ Project (KCRP) in Kenya, with the aim of understanding the extent to which it addressed equity, pa...

Coffee plays an important role in sustaining millions of livelihoods around the world. The production of Arabica coffee is greatly affected by the changing climate. Besides suffering from changing climate, coffee is also a contributor to climate change as a result of greenhouse gases emitted throughout the supply chain. The coffee sector is therefo...

This action plan has been developed to guide conservation of the Taita Thrush Turdus helleri and the Taita Apalis Apalis fuscigularis, both of which are Critically Endangered bird species endemic to the Taita Hills mountain block in south eastern Kenya, East Africa. The Taita Thrush is confined to montane cloud-forest, not venturing into secondary...

Research collaboration between developed countries from the northern hemisphere and developing countries in the southern hemisphere is essential for the understanding and protection of the major proportion of biodiversity located in the tropics. Focusing on the case of sub-Saharan Africa, we here assess the real involvement of northern versus south...

We examined the effects of vegetation composition and structure on bird species diversity and richness of foraging guilds in the highland agricultural landscape of Nyandarua, Kenya. Bird point counts and vegetation surveys were undertaken during four sampling periods. Linear mixed models were used to examine the effects of vegetation variables on b...

Global environmental policy and negotiations are important. They are the arenas where we seek to distinguish ourselves from other animals by summoning our empathy and benevolence - so-called humanity - and work collectively towards a common goal. It is a lofty aspiration certainly worth pursuit, albeit we really have little to show for it, either f...

Because of the high, albeit seasonal, availability of carcasses, the Mara-Serengeti ecosystem, Kenya, has a high diversity of scavengers, leading to considerable competition between species. From patterns of occurrence of vultures at 163 carcasses over an 8-year period in the Masai Mara National Reserve, we were able to identify some mechanisms tha...

Using science knowledge to guide conservation action remains difficult; communication gaps persist, especially between scientists and other stakeholders including policy makers. Here, we demonstrate how we have managed to integrate scientific knowledge into consensually formulated conservation actions in the Taita Hills, Kenya. GIS-based least-cost...

Habitat fragmentation can restrict geneflow, reduce neighbourhood effective population size, and increase genetic drift and inbreeding in small, isolated habitat remnants. The extent to which habitat fragmentation leads to population fragmentation, however, differs among landscapes and taxa. Commonly, researchers use information on the current stat...

SummaryThe Taita Apalis Apalis fuscigularis (IUCN category: Critically Endangered) is a species endemic to south-eastern Kenya. We assessed population size and habitat use in the three forest sites in which it is known to occur (Ngangao, Chawia and Vuria, totalling 257 ha). The estimate of total population size, derived from distance sampling at 41...

A survey of bird species of the Ol Donyo Sabuk National Park was carried out between 24 October and 2 November 2007. From 14 1-km transects distributed across the three habitat categories-forest, woodland and grassland-dominant in this park, 913 individual birds comprising 72 species were recorded. An additional 53 species were recorded from opport...

Between November 2007 and February 2008, bird species composition, richness and abundance were assessed at Gongoni Forest Reserve (classified as a Key Biodiversity Area) using transect and timed-species counts. A total of 140 bird species in 51 families were recorded with species accumulation curves indicating that a few more species could be disco...

Between March 2005 and February 2006 we surveyed the large and medium sized mammals ( > 5 kg) of Arawale National Reserve, NE Kenya. Twenty-three mammal species were counted during the period, using ground transects. This included eight species listed in the 2008 IUCN Red List of Threatened Species. Densities and biomass of the larger mammals in th...

Vertebrate population dynamics, social organisation and space use often are closely associated with the distribution of critical resources, such as food. Tree squirrels are ideal models to study these relationships, since both key demographic parameters (reproduction, survival and dispersal) and spatio-temporal variation in food supplies (measured...

Habitat attrition may affect ranging patterns of individuals in natural populations, e.g. by engendering larger territory sizes as the preferred habitat decreases. Radio-telemetry was used to explore the ranging behaviour of the white-starred robin Pogonocichla stellata in the highly fragmented Taita Hills landscape, south-east Kenya. Thirty-one ma...

Sound knowledge of underlying mechanisms is essential for understanding how species respond to habitat fragmentation. Because most threatened species are typically the first ones to suffer local extinctions with forest fragmentation, studying why they fare poorly at the broader landscape scale is difficult. Related, sympatric but common species may...

Attrition and fragmentation of natural habitats remains one of the most persistent problems for conservationists. Exactly how habitat loss leads to the loss of biodiversity is not easily pinned down, and varies across species, taxonomic groups and landscapes. Integrating theory with conservation on the ground is challenging due to the multi-faceted...

Whether or not subdivided populations persist in fragmented landscapes primarily depends on how well individuals can survive within discrete habitat patches. Using data from six capture–recapture sessions, survival probabilities of the white-starred robin were estimated in seven indigenous forest patches in the highly fragmented Taita Hills forests...

Bird conservation remains low on the agenda in Sub-Saharan Africa whereas, overall, things are getting worse. Why is this the case when interest, reflected for example in the number of young ornithologists, seems to be growing? For some sites and species, there is a genuine lack of data required to back calls for conservation action. BirdLife Inter...

We studied the presence of 'floaters', i.e. non-territorial individuals roaming occupied territories awaiting future breeding opportunities, in two separate White-starred Robin (Pogonocichla stellata) populations at the Taita Hills, Kenya, using a removal experiment. Previous vegetation analyses at this site had showed that 'population Ngangao' occ...

Demographic attributes of discrete subpopulations of animals and plants that constitute a larger (meta)population network may affect the strength and direction of local population responses to habitat loss or degradation. To address this question in an Afrotropical context, we studied survival rates, population densities, sex ratios and age distrib...

Nest predation accounts for a substantial share of nest failure and low reproductive success in most tropical songbirds. Normally, forest fragmentation leads to an increase in nest predation pressure due to reduced cover, fewer (and poorer) nest sites and predator influxes from the surrounding habitats. To test this hypothesis, we studied natural n...

We studied the spatial and temporal variation in fruit abundance and frugivorous bird densities in a large-sized (135ha), a medium-sized (95ha) and five small-sized (each 2-8ha) forest fragments in the Taita Hills, Kenya. The large and medium patches were respectively divided into six and three plots, while the small patches were each treated as a...

We examined the effects of habitat fragmentation of the white-starred robin Pogonocichla stellata metapopulation in the Taita Hills archipelago, a hotspot for biodiversity which was fragmented approximately 40 years ago. Using seven microsatellite markers, we analysed the robin's genetic structure and tested for equilibrium between migration and dr...

What factors determine the persistence of species in fragmented habitats? To address this question, we studied the relative impacts of forest deterioration and fragmentation on bird species in 12 rainforest fragments in Kenya, combining 6 years of individual capture-recapture data with measurements of current captures and museum specimens. Species...

Factors influencing the interaction between fruiting trees and their frugivorous seed dispersers in fragmented Afrotropical landscapes are poorly known. With the use of Mantel statistics we analysed assemblages of frugivorous birds on 58 individual trees belonging to 11 species growing in seven Kenyan cloud forest fragments. Overall, frugivores sho...

Fruit-eating birds play an important role in the seed dispersal of many tropical plants (e.g. Herrera 1984), and the foraging behaviour of avian frugivores may affect their seed-dispersal capabilities (Loiselle & Blake 1999,Schupp 1993, Traveset 1994). For instance,shorter visits tend to produce less clumped seed distributions (Graham et al. 1995)....

Three forest and woodland sites were surveyed in the lowlands of the East Usambara mountains, Tanzania, from August to October, 1996. Bombo East I and II Proposed Forest Reserves (PFR) and Bombo West FR were previously unknown biologically. Our fieldwork revealed several records of conservation interest. Four species of global conservation concern...