IntroductionSubtitle: Impact of Seasonal Variation in Fruit Species Richness on the Diversity of Obligate Avian Frugivores
This study aims to assess the health and capacity of habitats for supporting frugivorous species by highlighting the extent to which seasonality affects fruit availability and impacts frugivorous communities. It will also provide measures that can be implemented by conservationists and policy makers in order to highlight the habitats and landscapes that promote high survival and reproduction across seasons.
Researcher: Michael ChunguCountry: Zambia
Partner Organisations: Copperbelt University; Chembe Bird Sanctuary – Kalulushi; Department of National Parks; Wildlife Zambia
BackgroundThe project is a prerequisite for earning a Bachelor of Science in Wildlife Management degree and is completed during the student’s final year. Michael has field experience working with the Department of National Parks and Wildlife Zambia during his industrial attachments.
ObjectivesThe results of this project aim to add more knowledge about seasonality and birds to the scientific archive of knowledge with the following objectives:
1. Assess the species richness of fruiting trees in wet and dry seasons. This will involve establishing a map for the study area using Global Information System (GIS) software and a Global Positioning System (GPS), randomly picking sampling points and collecting pictures, leaves and other relevant material from fruiting trees.
2. Assess the abundance of obligate avian frugivores in wet and dry seasons. This is being achieved by counting the number of obligate avian frugivores at the sampling points using a digital camera and binoculars.
3. Assess species richness of obligate avian frugivores in the wet and dry seasons using statistical packages and software installed on a personal computer.
4. Determine the diversity of obligate avian frugivores in the wet and dry seasons – using statistical packages and software installed on a personal computer.
Results may also be published in ornithological journals such as Birdlife Zambia, Birdlife International and the African Bird Society.
The study is being conducted in the Copperbelt Province in Chembe Bird Sanctuary, Zambia. It is situated in Kalulushi, 30 km south-west of Kitwe and covers an area of about 450 hectares (1 112 acres). The study area is mainly composed of miombo woodland and grassland vegetation types and is a protected area characterised by diverse birdlife. The average annual temperature in the study area is 19.7 °Celsius. The rainfall here averages 1 288 mm. Mammalian species are minimal, though primate and carnivorous species such as vervet monkeys and spotted-necked otters are seen in the area. The woodland habitat is the sampling frame for this study, as such forests are known to offer a range of fruiting trees at high densities, including several species that are rare in other forest types.
Point-counts will be used to estimate the abundance and species richness of obligate avian frugivores. The point count method was chosen to ensure that sampling effort, habitat type and area surveyed were the same at all sites. Fifteen sample points (n=15) each spanning 100 m in radius will be placed randomly and located using a GPS receiver. This will cover a total area of about 47 hectares (116 acres), thereby ensuring a sampling intensity of more than 10%. The sampling points will be placed 100 m apart to avoid overlap and recounts, and 15 minutes will be spent at each point, with 5 minutes allowed for settling down and 10 minutes for counting birds.
All bird counts are carried out in the morning within 5 hours of sunrise and all frugivorous birds recorded when seen feeding on fruits. Fruit richness will be determined from these sampling points by counting the different species within a 50 m radius of the sampling points.
This research will be conducted in two seasons, namely the wet and dry seasons. The wet season runs from January to March and the dry season from June to August. The study will be conducted between June 2016 and June 2017. All data about Zambian obligate avian frugivores will be compiled from a comparison between the African avian frugivores list provided in Kissling, et al., 2007 and the Zambian Bird List as provided by the Zambia Ornithological Society.
The diversity of obligate avian frugivores in the wet and dry seasons will be compared to the richness of fruits in the wet and dry seasons.
This will be conducted at multiple levels:
• Firstly, the species richness of fruits in the two seasons will be established using the Shannon-Wiener index and compared.
• Secondly, the Shannon-Wiener index will be used to calculate the species richness of obligate frugivores in the different seasons and compared.
• Thirdly, Analyses of Variance (ANOVA) will be performed on the abundance of obligate avian frugivores using Excel Solver (Excel statistical software).
• Lastly, a multiple regression will be used to compare the diversity of obligate avian frugivores in the wet and dry seasons. Bird species diversity will be calculated using the Shannon-Wiener index. This index has the advantage that its values in different areas and habitats can be tested using ANOVA.
In the first and second quarters of the running of this project, I submitted a proposal to the lecturer and supervisor for review and corrections. The proposal was marked and suggestions for corrections were made.
Since then, I have been working on their suggestions and working out with my supervisor how best the objectives can be modified to fit in the new academic calendar. Some sugested additions included the addition of the method for fruiting trees classification and classification of obligate avian fruigivores. This will be resolved by classifying the fruiting tree spcies using Van Wyk & Van Wyk (1997) whereas the classification of obligate fruigivores will be according to Newman (2000).
As for the research objectives, the two possibilities that were suggested were to collect data in the rain season only, whereas the other is to do the dry season data collection as early as May, 2017. I have so far purchased a laptop and ordered a camera and binoculars as my research tools. Another challenge I am facing is finding a Global Positioning System (GPS) receiver as this was not included on the research budget. I hope to rent the GPS receiver. I also contacted the area ecologist of Chembe Bird Sanctuary who comfirmed the presence of fruits during the research season. I will therefore use Chembe for data collecton as soon as the research tools I ordered are delivered.