Browsing by Author "Cordeiro, Norbert J."
Now showing 1 - 14 of 14
Results Per Page
Sort Options
Item Allanblackia, A New Tree Crop in Africa for The Global Food Industry: Market Development, Smallholder Cultivation And Biodiversity Management(Taylor & Francis, 2009-12) Jamnadass, Ramni; Dawson, Ian K.; Anegbeh, Paul; Asaah, Ebenezar K.; Atangana, Alain; Cordeiro, Norbert J.; Hendrickx, Harrie; Henneh, Samuel; Kadu, Caroline A. C.; Kattah, Cyril; Misbah, Maha; Muchugi, Alice; Munjuga, Moses; Mwaura, Lucy; Ndangalasi, Henry J.; Njau, Chrispine S.; Nyame, Samuel K.; Ofori, Daniel A.; Peprah, Theresa; Joanne, Russel; Rutatina, Fidelis; Sawe, Corodius; Lars, Schmidt; Tchoundjeu, Zac; Simons, TonyThe seeds of Allanblackia trees produce edible oil with significant global market potential. Consequently, a private-public partnership involving Unilever and known as 'Novella Africa' is engaged in the development of Allanblackia as a new crop in a number of African countries. The purpose of this partnership is to build a profitable and sustainable initiative for harvest, marketing and cultivation. Rural communities are directly involved and a participatory approach to domestication is being followed to maximise fanners' livelihood benefits. This is the first time a multinational company has partnered in such an approach, and the initiative represents an example for the domestication of other new tree crops. Investing in good communication between partners is considered to be essential to success by ensuring trust and a common understanding of priorities. Progress to date has involved the establishment of market supply chains for oil, based firstly on wild harvest, and the initiation of cultivation by smallholders. Further work will involve the development of rural resource centres to deliver improved germplasm to growers. At the same time, these centres will provide other services such as market information, credit and access to buyers. Through this strategy it is foreseen that there will be progress towards the development of a market value chain which removes producers' constraints to profitable involvement. Furthermore, the diversification of farmers' cropping systems should have positive impacts for biodiversity and provide resilience in the face of climate change. Currently, the most important activity under the initiative is the promotion of Allanblackia planting, so that production constraints do not hamper market development.Item Aspects Of The Floral and Fruit Biology of Allanblackia Stuhlmannii (CLUSIACEAE), An Endemic Tanzanian Tree(2009-07) Mathew, Mathayo M.; Munjuga, Moses; Ndangalasi, Henry J.; Cordeiro, Norbert J.Various economically important tropical tree species are not well known biologically. We studied the floral and fruit biology of Allariblackia stuhlmannii (Clusiaceae), a dioecious tree species endemic to the Eastern Arc Mountains of Tanzania and Kenya that has become the subject of recent interest by the food industry because of the edible oil that can be extracted from the seeds. We characterised qualitative and quantitative similarities and differences between male and female flowers, the flowering and fruiting phenology, and examined the relationship between fruit crop production and tree size, seeds per fruit, and seed number as a function of fruit mass. There was no significant difference in sugar concentration of nectar between male and female flowers, but male flowers contained significantly more nectar than female flowers. Male trees had larger flowering displays with a tendency for the population to mast profusely between January and March, which coincided with the peak fruiting period. The fruiting period was pronounced from January to March, which appeared to be preceded by a smaller peak in October. Fruit crop was strongly related to tree size, with mean seed number per fruit being 38. Seed quantity per fruit showed a trend to increase with fruit mass, but this relationship was not significant. General physical resemblance of female flowers to male flowers, the latter of which offer multiple floral cues to attract pollinators, suggests a pollination-by-deceit strategy. Our results provide important insights on the natural history of this tree species and carry implications for its future use.Item The biological importance of the Eastern Arc Mountain of Tanzania and Kenya(2007-01) Burgess, Neil D.; Butynski, Thomas M.; Cordeiro, Norbert J.; Doggart, Nike; Fjeldså, Jon; Howell, Kim; Kilahama, Felician B.; Loader, Simon; Lovett, Jon C.; Mbilinyi, Boniface P.; Menegon, Michele; Moyer, David; Nashanda, Evarist; Perkin, Andrew; Rovero, Francesco; Stanley, William T.; Stuart, Simon N.The Eastern Arc Mountains are renown in Africa for high concentrations of endemic species of animals and plants. Thirteen separate mountain blocks comprise the Eastern Arc, supporting around 3300 km2 of sub-montane, montane and upper montane forest, less than 30% of the estimated original forested area. At least 96 vertebrate species are endemic, split as follows: 10 mammal, 19 bird, 29 reptile and 38 amphibian species. This includes four endemic or nearly endemic species of primate – the Sanje Mangabey, the Iringa Red Colobus, the Mountain Galago and the new Kipunji monkey that forms its own monotypic genus. A further 71 vertebrate species are near-endemic. At least 800 vascular plant species are endemic, almost 10% of these being trees. These endemics include the majority of the species of African violet – Saintpaulia, a well-known flowering plant in Western households. An additional 32 species of bryophytes are also endemic. Many hundreds of invertebrates are also likely to be endemic, with data for butterflies, millipedes and dragonflies indicating potential trends in importance. Seventy-one of the endemic or near-endemic vertebrates are threatened by extinction (8 critical, 27 endangered, 36 vulnerable), with an additional seven wide ranging threatened species. Hundreds of plant species are also threatened. Most Eastern Arc endemics are closed-forest specialists and comprise taxa with an ancient history and those of more recent origin, including some possessing ancient affinities with taxa from West Africa, Madagascar, and even South America and Southeast Asia. Mountain block prioritisation for biodiversity conservation shows that Udzungwas, East Usambaras and Ulugurus are the most important blocks, with other important blocks being the Ngurus and West Usambaras. Rankings are correlated closely with the area of remaining forest. Most of the remaining forest is found within nearly 150 Government Forest Reserves, with 106 of these managed nationally for water catchment, biodiversity and soil conservation and where forest exploitation is not allowed. Outside these areas most forest has been cleared, except in small village burial/sacred sites, a few Village Forest Reserves, and inaccessible areas. In most Eastern Arc Mountains the local populations have not encroached beyond the reserve boundaries to develop farms, but forest resources within the boundaries are used for fuel and building materials and some forests are heavily degraded. Fire is also a problem as it enters and destroys forests during the dry seasons. The future of the biodiversity on the Eastern Arc Mountains is closely tied to management policies and capacity of the Tanzania Forestry and Beekeeping Division, Tanzania National Parks Authority, and Kenya Forest Department. Supporting these agencies in their mandated job is an essential conservation investment over the longer term.Item Diet Of The Silvery-Cheeked Hornbill Bycanistes Brevis During the Breeding Season in The East Usambara Mountains, Tanzania(Taylor & Francis, 2016-01) Cordeiro, Norbert J.; Campbell, Joshua T; Ndangalasi, Henry J.The breeding season diet and nesting characteristics of the Silvery-cheeked Hornbill Bycanistes brevis are poorly known. To further understand these aspects of the breeding biology of this hornbill species, 14 nests were studied in and around Amani Nature Reserve located in the East Usambara Mountains, Tanzania. Nesting tree species were identified and the diet composition of nesting hornbills was evaluated between July and November 2001. The ejecta from each nest were collected, inventoried, identified (as completely as possible) and enumerated. Food items were categorised as plant, vertebrate or invertebrate. Plants, represented largely by fruits, were the dominant food type (n = 861), followed by invertebrates (n = 306; mainly millipedes and beetles), and vertebrates (n = 15; mainly smaller birds and chameleons). A comparison of results from the current study to other nesting observations made approximately seven decades earlier in the same area suggest that (1) the invasive tree species Maesopsis eminii, which was the most common food type consumed (n = 4 539 seeds), has become a favoured new food source in the breeding season, and (2) the breeding season appears to have shifted to an earlier period, potentially due to the fruiting phenology and abundance of Maesopsis eminii.Item Disperser Limitation and Recruitment of an Endemic African Tree in a Fragmented Landscape(Wiley, 2009-04) Cordeiro, Norbert J.; Ndangalasi, Henry J.; McEntee, Jay P.; Howe, HenryForest fragmentation may have positive or negative effects on tropical tree populations. Our earlier study of an endemic African tree, Leptonychia usambarensis (Sterculiaceae), in the East Usambara Mountains of Tanzania, found poorer recruitment of seedlings and juveniles in small fragments compared to continuous forest, and concomitant reduction of seed-dispersal agents and seed dispersal. However, the possibility that other biotic or abiotic consequences of the fragmentation process contribute to diminished recruitment in fragments was left open. Here we test whether excessive seed predation, diminished fecundity, low seed quality, or adverse abiotic effects acted independently or in concert with reduced seed dispersal to limit seedling and juvenile recruitment in fragments. Extended observations of disperser activity, a seed placement experiment, seed predator censuses, and reciprocal seedling transplants from forest and fragment sources failed to support the alternative hypotheses for poorer seedling and juvenile recruitment in fragments, leaving reduced seed dispersal as the most plausible mechanism. Poorer recruitment of this species in forest fragments, where high edge-to-area ratios admit more light than in continuous forest, is particularly striking because the tree is an early successional species that might be expected to thrive in disturbed microhabitats.Item In Search of Sustainable Seed Harvest: Seed Removal and Establishment of an Endemic African Rainforest Tree(2012-08) Seltzer, Carrie E.; Kremer, Colin T.; Ndangalasi, Henry J.; Cordeiro, Norbert J.Background/Question/Methods Harvest of non-timber forest products such as seeds requires assessment to determine if it is sustainable. Allanblackia stuhlmannii (Clusiaceae) is a rainforest tree with seeds that are harvested for an emerging commercial market. Seeds that are not collected by humans are mostly scatterhoarded by giant pouched rats (Cricetomys gambianus). Two simultaneous experiments were conducted in twelve 50x50m plots within the Amani Nature Reserve: a seed tagging experiment that followed fates of 1152 seeds (in two rounds of 576 seeds each), and a seed planting experiment that followed fates (until disappearance) for 960 seeds (in two rounds). We recorded fruit abundance in each plot throughout the fruiting season and followed seed fate for approximately one year. This presentation will address the goal of determining how seed removal and fate vary with background seed abundance for experimentally planted seeds. We use generalized additive models to investigate the relationship between the persistence of seeds in their original locations and covariates such as fruit abundance, seed weight, and rodent activity. This allows us to estimate the persistence and germination probabilities of Allanblackia seeds under different conditions. Results/Conclusions We observed rapid removal of experimentally planted seeds within the first twelve days, followed by low levels of removal over several weeks. During the first five months of the experiment, fruit abundance within a plot affected the proportion of seeds that persisted in a non-linear way. Comparison between general additive models including seed weight and both logistic and lowess relationships with fruit abundance indicated that seed persistence was depressed at intermediate fruit abundances. A second intense period of seed removal occurred between the fifth and sixth months, after the Allanblackia fruiting season, after which all plots had similar proportions of seeds remaining. Seed removal during this second event was unrelated to fruit abundance, and may correspond to a period of low resource availability for rodents. Interestingly, seed weight did not have consistent or significant effects on seed persistence over time. Ultimately, approximately 5% of the seeds germinated where they were planted in the first ten months of the experiment. Seeds removed from the planting experiment were likely either consumed or scatterhoarded and could have germinated elsewhere. Consequently, understanding the fates of removed seeds will depend on results from the seed tagging experiment.Item Isolation and development of 13 new, polymorphic microsatellite loci for a threatened, understory tree, Mesogyne insignis, (Moraceae) from the Eastern Arc Mountains(Springer, 2012-02) Murdoch, Kellie C.; Ndangalasi, Henry J.; LeCaptain, M. K.; Clement, W. L.; Feldheim, Kevin A.; Cordeiro, Norbert J.Fourteen microsatellite loci were isolated from Mesogyne insignis, a threatened, African understory tree. Alleles ranged between two and eight per locus, with expected heterozygosity ranging from 0.063 to 0.845 and observed heterozygosity ranging from 0.000 to 0.733. One locus departed from Hardy–Weinberg equilibrium leaving 13 polymorphic loci that will be used to study the genetic variability of fragmented populations so as to enhance the species conservation efforts.Item Microsatellite Loci For Two East African Tree Species, Leptonychia Usambarensis (Sterculiaceae) and Sorindeia Madagascariensis (Anacardiaceae)(wiley, 2008-11) Cordeiro, Norbert J.; Feldheim, Kevin A.; Ikejimba, E.; Ndangalasi, Henry J.We isolated 20 trinucleotide microsatellites from two African tree species: Sorindeia madagascariensis (nine microsatellites) and Leptonychia usambarensis (11 microsatellites). Number of alleles ranged from three to seven in Sorindeia and two to 10 in Leptonychia. Observed heterozygosity ranged from 0.025 to 0.829 for Sorindeia and from 0.226 to 0.933 for Leptonychia. Two loci from each species departed from Hardy-Weinberg equilibrium. These microsatellite markers will be used to study how forest fragmentation affects pollination and seed dispersal processes of these tree species.Item Notes on the Ecology and Status of Some Forest Mammals in Four Eastern Arc Mountains, Tanzania(2004-12) Cordeiro, Norbert J.; Seddon, Nathalie; Capper, David R.; Ekstrom, Jonathan M. M.; Howell, Kim; Isherwood, Isabel S.; Msuya, Charles A.; Mushi, Jonas T.; Perkin, Andrew; Pople, Robert G.; Stanley, William T.From 1993 to 2000, observations were made of small to medium-sized mammals in seven poorly known submontane forest reserves and one village forest in the North Pare, South Pare, East Usambara and Nguu Mountains, Tanzania. Of 26 species recorded, three are Red-Listed as Threatened (Endangered: Zanj elephant shrew Rhynchocyon petersi; Vulnerable: red-bellied coast squirrel Paraxerus palliatus, and eastern tree hyrax Dendrohyrax validus) and five as Lower Risk (two dwarf galagos Galagoides spp., African buffalo Syncerus caffer, suni Neotragus moschatus, and Harvey's duiker Cephalophus harveyi). Most of our mammal records represent new distributions in the Eastern Arc Mountains, and one record of an unidentified squirrel in the Nguu Mountains is of conservation interest. Together with timber removal and cultivation, hunting appears to threaten the survival of mammals in these forests. There is an urgent need to establish long-term conservation programmes in these forests and more thorough surveys of mammals are necessaryItem Notes on the Ecology And Status of Some Forest Mammals In Four Eastern Arc Mountains, Tanzania(2004-12) Cordeiro, Norbert J.; Seddon, Nathalie; Capper, David R.; Ekstrom, Jonathan M. M.; Howell, Kim; Isherwood, Isabel S.; Msuya, Charles A.; Mushi, Jonas T.; Perkin, Andrew; Pople, Robert G.; Stanley, William T.From 1993 to 2000, observations were made of small to medium-sized mammals in seven poorly known submontane forest reserves and one village forest in the North Pare, South Pare, East Usambara and Nguu Mountains, Tanzania. Of 26 species recorded, three are Red-Listed as Threatened (Endangered: Zanj elephant shrew Rhynchocyon petersi; Vulnerable: red-bellied coast squirrel Paraxerus palliatus, and eastern tree hyrax Dendrohyrax validus) and five as Lower Risk (two dwarf galagos Galagoides spp., African buffalo Syncerus caffer, suni Neotragus moschatus, and Harvey's duiker Cephalophus harveyi). Most of our mammal records represent new distributions in the Eastern Arc Mountains, and one record of an unidentified squirrel in the Nguu Mountains is of conservation interest. Together with timber removal and cultivation, hunting appears to threaten the survival of mammals in these forests. There is an urgent need to establish long-term conservation programmes in these forests and more thorough surveys of mammals are necessary.Item Observations of threatened birds in the East Usambara Mountains, Tanzania(2007-12) Borghesio, Luca; John, Jasson; Mulungu, Elia; Mkongewa, Victor; Joho, Martin P.; Cordeiro, Norbert J.We report the preliminary observations and results of a survey of the birds of the East Usambara Mountains, north-east Tanzania. Using standardised point counts and opportunistic searches, we collected information on the distribution, habitat selection and relative abundance of those species of greatest conservation concern. Amongst the 124 species recorded during the survey, six are listed in the global Red Data book and nine are considered to be restricted-range. Forest edges and agricultural habitats had notable numbers of species of conservation importance. Habitat requirements of the species of conservation concern differed: whilst ground-foragers (Usambara Thrush Turdus (olivaceus) roehli, Modulatrix spp.) are clearly dependent on intact forest, Banded Sunbird Anthreptes rubritorques, Amani Sunbird Hedydipna pallidigastra, Fischer’s Turaco Tauraco fischeri, Kenrick’s Starling Poeoptera kenricki and Long-billed Tailorbird Artisornis moreaui are also frequent in successional habitats created by disturbance, at forest edges or even in relatively open, agricultural landscapes. This suggests that some threatened species might benefit from conservation initiatives (e.g., planting of useful indigenous trees) specifically targeted to counter the degradation of such ‘fringe’ habitats.Item Plants, Rats, and People: Seed Dispersal of an Economically Important Rainforest Tree In Tanzania(2011-08) Seltzer, Carrie E.; Kremer, Colin T.; Ndangalasi, Henry J.; Cordeiro, Norbert J.enus Allanblackia. Allanblackia stuhlmannii (Clusiaceae) is a canopy tree endemic to the Eastern Arc Mountains of Tanzania. Recently, humans have begun heavily collecting seeds throughout the Amani Nature Reserve (ANR) in spite of its prohibition, and there is concern that illegal seed harvest will diminish the regeneration of Allanblackia over the long term. The objective of this project was to determine how Allanblackia seed fate and dispersal varies under different levels of seed availability. Twelve 50 by 50 m plots containing at least 4 fruit-bearing trees were established in ANR. Seed addition within plots was recorded by counting the number of fresh fruits during each visit to the plot. Within each plot, removal trials were conducted at seed stations containing 16 seeds each. Each seed was weighed and marked with a wire, flag, and thread bobbin to aid in the post-dispersal recovery. Seeds were checked after 4, 8, 12, and 28 days and monthly thereafter. The location, dispersal distance, and condition of seeds was recorded at each visit. Each plot had one camera to identify seed dispersers at a subset of seed stations. Results/Conclusions Preliminary analyses show that increasing fruit abundance decreased the probability of seed removal and increased the time to seed predation/disappearance, but did not affect the distance seeds were moved. Seed weight did not influence the probability of being removed from a seed station but the distance moved increased with seed weight. Giant pouched rats (Cricetomys gambianus) were the most common seed dispersers (79% of 1514 photos). Seeds were broken off of the wires for nearly half of the seeds at some point in the experiment meaning the ultimate fate is unknown because it could have been re-cached or eaten. Monthly monitoring continues to follow seed fate of the remaining seeds. From these results we conclude that reduced seed availability, potentially due to human harvesting, alters Allanblackia seed predation and dispersal in ways that mayItem Seed Dispersal in the Dark: Shedding Light on the Role of Fruit Bats in Africa(Wiley, 2013-06) Seltzer, Carrie E.; Ndangalasi, Henry J.; Cordeiro, Norbert J.In spite of their recognized importance as seed dispersers in other parts of the tropics, seed dispersal by fruit bats has received scant research attention in Africa. To evaluate the role of African fruit bats in seed dispersal, we studied fruits and seeds below 480 bat feeding roosts in the East Usambara Mountains of Tanzania. We compared these findings to those reported in other African localities to place our results in a broader context. We found 49 plant species dispersed by bats: 28 species, 18 genera, and one family are novel reports of bat dispersal in Africa. Approximately 20 percent of the submontane tree flora of the East Usambaras is bat-dispersed, including both widespread and endemic trees. African fruit bats are important seed dispersers at our study site because they move seeds of dozens of species tens or hundreds of meters, even seeds that are too large to ingest (greater than 5 mm in length). Fruit bats are likely important seed dispersers in other Afrotropical forests, as bats elsewhere in Africa are known to consume 20 genera and 16 species of plants reported here. Insights from studying remains under bat feeding roosts offer a simple method to further document and substantially increase our understanding of the role of African fruit bats in seed dispersal.Item Seed Harvesting of A Threatened African Tree Dispersed by Rodents: Is Enrichment Planting A Solution(Elsevier, 2015-03) Seltzer, Carrie E.; Kremer, Colin T.; Ndangalasi, Henry J.; Cordeiro, Norbert J.Non-timber forest products (NTFPs) provide income to local communities with less ecological harm than timber extraction. Yet overharvesting can still influence the regeneration and sustainability of these resources. Developing sustainable harvesting practices for emerging NTFPs depends on the biology of the NTFP species, the ecological context in which management occurs, and its cost in terms of effort and resources. Allanblackia stuhlmannii (Clusiaceae) is a canopy tree species whose seeds are a source of vegetable oil and an important food for rodents. In an experiment within the Amani Nature Reserve (Tanzania), we studied how enrichment planting of A. stuhlmannii seeds affected germination and establishment rates under varying local levels of seed abundance and rodent activity. Overall, germination and establishment rates were high (4.8% and 2.2%, respectively, after 11 months), while local ecological conditions had a short lived (1–2 weeks) and unexpectedly small influence on the persistence of planted seeds. Given these rates, we estimate a cost of approximately US$0.14 per seedling. Enrichment planting of seeds, across a range of local ecological conditions, appears to be a viable and cost effective management strategy for increasing A. stuhlmannii recruitment in harvested areas.