Sixth International Conference of the Pan African Fish and Fisheries
Total Page：16
File Type：pdf, Size：1020Kb
SIXTH INTERNATIONAL CONFERENCE OF THE PAN AFRICAN FISH AND FISHERIES ASSOCIATION (PAFFA6) BOOK OF ABSTRACTS Sun N Sand Holiday Resort in Mangochi, Malawi 24th to 28th September 2018. “African Fish and Fisheries: Diversity, Conservation and Sustainable Management” About This Booklet This publication includes abstracts for oral presentations and poster presentations at the Sixth International Conference of The Pan African Fish And Fisheries Association (PAFFA6) held at Sun ‘n’ Sand Holiday Resort in Mangochi, Malawi from 24-28 September, 2018. Section One: Oral Presentations Oral presentations are grouped by conference theme. Please refer to the Conference Programme for details about date, time slot and location for each thematic session. Section Two: Poster Presentations Poster presentations are grouped by conference theme. Please refer to the Conference Programme for details about date, time slot, and location for group poster sessions. All presentations are subject to change after the printing of this publication. The 2018 PAFFA book of abstracts is sponsored by the Fisheries Integration of Society and Habitats Project (FISH) which is made possible by the generous support of the American people through the United States Agency for International Development (USAID) and implemented by Pact. "The contents, are the sole responsibility of LUANAR, Conference Organisers and Delegates and do not necessarily reflect the views of the FISH Project team and partners, USAID, or the United States Government (USG). 1 | P a g e “African Fish and Fisheries: Diversity, Conservation and Sustainable Management” KEY NOTE PRESENTATIONS – PLENARY SESSIONS (NYANJA HALL) Day 1, Monday, 24th September, 2018 Rapid Radiation of the Cichlids of Lake Malaŵi Jay R. Stauffer, Jr. and Adrianus F. Konings The cichlid fishes of Lake Malawi probably represent one on the best examples of rapid radiation of vertebrates. The species status and phylogenetic relationships of many of these fishes continue to remain unresolved. The taxonomic uncertainty of these fishes prompted authors studying these fishes to promote the use of a combination of morphological, genetic, and behavioral data (Stauffer et al. 1995; Stauffer and McKaye 2001) to diagnose the taxonomic status of these fishes. The importance of behavioral information has been undervalued in the assignment of autapomorphic and synapomorphic characters to the varying levels in the Linnean hierarchy of these fishes. Behavioral differences have suggested that various populations were, in fact, heterospecific. We identified different populations of sibling species by observed differences in color patterns, bower shape, or courtship behavior. Once these differences were observed, various authors were able to discover morphological and genetic differences to diagnose these species. Without the behavioral information, many of these species would have remained undiscovered. Secondly, differences in the shape of bowers and courtship dances not only identify different species, but also, provide important information needed to construct phylogenetic relationships. Finally, given the diversity of these Lake Malawi fishes, we conclude that detailed in situ and laboratory studies on the behavior of these organisms, are necessary to reveal the evolutionary processes and patterns of speciation among Lake Malawi haplochromine cichlids. Day 2, Tuesday, 25th September, 2018 Understanding Adaptive Radiation and Explosive Diversification Through Cichlid Fish Genomics Walter Salzburger Zoological Institute, University of Basel, Switzerland. EMail: [email protected] Owing to their spectacular taxonomic, phenotypic, ecological and behavioral diversity and propensity for explosive speciation, the assemblages of cichlid fishes in the East African Great Lakes Victoria, Malawi and Tanganyika are prime role models in evolutionary biology. With the release of five reference cichlid genomes and many additional genomic resources as well as the establishment of functional genomic tools, the cichlid system has fully entered the genomic era. The in-depth genomic exploration of the East African cichlid fauna — in combination with the examination of their ecology, morphology and behavior and 2 | P a g e “African Fish and Fisheries: Diversity, Conservation and Sustainable Management” information on the geological history of the Great Lakes — permits novel insights into the way how organisms diversify and how adaptive radiations progress. Day 3, Wednesday, 26th September, 2018 The Evolution of Extreme Phenotypic Convergence across Fish Lineages in the Hyper- Diverse Lower Congo River - M.L.J. Stiassny1, R.J.C. Monsembula Iyaba2, T. Liyandja1,2, J. J. Mbimbi Mayi Munene2, M. Yoko2, E. Alter3. 1American Museum of Natural History, Department of Ichthyology, New York, New York, USA 2Université de Kinshasa, Département de Biologie, Kinshasa, Democratic Republic of Congo 3York College/City University of New York, Department of Biology, Jamaica, NY, USA Recent estimates of species richness in the Congo basin vary but converge on a number close to 1270. However, that diversity is not evenly partitioned and the lower Congo River (LCR) is highlighted as a hotspot of species richness and endemism within the basin. In marked contrast to the river upstream of Pool Malebo, the LCR channel is entirely bedrock, and littoral habitats are mostly rocky and rock strewn. In situ measurements have recorded dramatic changes in channel topology and in addition to fluctuating bed bathymetry, regions of extreme depth have also been recorded. A combination of high annual discharge, steep elevational incline, and fluctuating channel width and depth result in high-energy flow regimes throughout the system. These hydrological features appear to play a key role in isolating fish populations by restricting both cross-channel and upstream-downstream movement, and likely present powerful drivers for micro-allopatric isolation often over remarkably small geographical scales. Among the many species endemic to the LCR are a group of distantly related fishes exhibiting a striking series of multi-trait morphological convergence (including microphthalmia or eye loss, depigmentation, laterosensory enhancement etc.). These “cryptophthalmic” forms have arisen independently in at least six phylogenetically disparate families (Cichlidae, Mastacembelidae, Mochokidae, Claroteidae, Clariidae, Mormyridae), likely in response to similar selective pressures within the extreme environments of the LCR. Here we present results of an ongoing investigation to characterize and quantify of this case of extreme eco-morphological convergence. Day 4, Wednesday, 27th September, 2018 One Man’s Meat Is another’s Poison: Benefits, Impacts and Conflicts of Fisheries Based on Alien Species in South Africa Olaf LF Weyl DST/NRF Research Chair in Inland Fisheries and Freshwater Ecology, South African Institute for Aquatic Biodiversity (SAIAB), Grahamstown 6139, South Africa Southern Africa has a long history of introductions of aquatic plants, invertebrates and fish. Direct introductions, escapes from captivity, and unintentional spread have resulted in many introduced species becoming invasive. Impacts of invasions include the predation on and competition with native biota, habitat alterations, disease transfer and hybridization with 3 | P a g e “African Fish and Fisheries: Diversity, Conservation and Sustainable Management” native species. While the control of nuisance species (e.g., water hyacinth Eichhornia crassipes) typically enjoys public and institutional support, attempts to control species that have negative environmental but positive economic impacts often results in conflicts between stakeholders e.g., conservation authorities, fisheries departments, anglers and/or aquaculture practitioners. In a region where inland fisheries and aquaculture are investment areas for addressing economic development, food security and poverty eradication, resolving such conflicts is crucial if invasions are to be managed effectively. Here I provide an overview of the current knowledge on invasion pathways, status and ecological impact of two southern African conflict species: rainbow trout Onchorhynchus mykiss and Nile tilapia Oreochromis niloticus. These are discussed in the context of social and economic benefits derived from these species, the strong opposition to management interventions intended to contain invasions, and the process that South Africa is engaged in to try to negotiate potential win-win solutions. Consequences of Stocking Tilapia Species outside their Natural Ranges in Tanzania - Assessed by Genome Sequencing Turner GF1, Ford AGP2, Genner MJ3, Ngatunga BP4, Shechonge A5, Haerty W6, di Palma F6 1Bangor University UK, 2University of Roehampton UK,3University of Bristol UK, 4formerlyTAFIRI Tanzania, 5University of Dar Es Salaam, Tanzania, 6Earlham Institute UK Global attention has focussed on the threat to long-term food security posed by the impacts of climate change and emerging diseases and pests on crops which often have limited genetic diversity. For this reason, major initiatives have been launched to preserve wild relatives and local domesticated strains of crops, including the creation of a multimillion dollar seed bank on the Arctic island of Svalbard. Similar issues are likely to threaten the tilapia aquaculture industry, now dominated by a few fast-growing strains of Nile Tilapia: for example the emergence of Tilapia Lake Virus (TiLV). East Africa, particularly Tanzania, is a