Geomorphological Potential of Coelacanth Habitat across Mozambique-Tanzania Border

The coelacanth is a new fish in Tanzania. It was first discovered in September 2003 after it was spotted by a tourist in a fish market. It was caught by fishermen in the deep waters off Songo Mnara Island offshore of Kilwa Masoko Town in Southern Tanzania. The find potentially added southern Tanzania to the list of known coelacanth areas of the southern Western Indian Ocean Region. Observed current conditions indicate that the waters are swept by strong (2 m/sec) northward flowing current. This suggests that there must exist hideouts for the fish, such as caves in canyons and overhangs. Carefully analysed single cruise bathymetric data obtained from the region indicate existence of canyons off the Tanzania- Mozambique border region, which are believed to provide habitat to the fish. The data point to the potential of the area as habitat for the elusive coelacanth.Tanz. J. Sci. Short Comm. Vol. 36 2010, 113-11

Ecological and engineering importance of the Bet el Ras beach-sandstone

A unique sandstone known as the Bet el Ras sandstone, supposedly of Holocene age, occurs profusely along the western coast of Unguja but more extensive at its locality area, Bet el Ras, where it forms a rocky shore. The sandstone has been blasted in the past for construction of the sea wall that fronts the Zanzibar Town, and stands to be blasted further for renovation works. From the results of the survey made, it is clear that the sandstone is ecologically and environmentally important such that its total removal will lead to loss of a habitat as well as enhance coastal erosion and sediment input in the littoral zone thereby impacting on the ecology of the associated flora and fauna. Since none of the fauna species is endemic and due to its engineering importance, selective extraction may be considered such that extraction of the sandstone be done in steps and cavities be refilled as well. A thin veneer may also be left close to the land as protection against erosion. This will also minimize sediment input in the littoral zone that would otherwise have affected the community structure. Tanzania Journal of Science Vol. 32 (2) 2006: pp. 117-12

Sediment characteristics and hydrodynamic setting of reef platform sediments of Kunduchi, north of Dar es Salaam harbour

Sediment grain size distribution, carbonate content and current velocities for the Kunduchi area are used to determine its hydrodynamic setting and sediment characteristics. The sediment mean grain size generally decreases northward. The sediments consist of medium to coarse sand south of the Tegeta River and fine sand further north. The sediment sorting values, which lack a north-south trend, vary from moderately well sorted to poorly sorted. The skewness of the sediment vary from near-symmetrical to very negatively skewed while the peakedness (kurtosis) varies from platykurtic to leptokurtic. The carbonate content increases with distance offshore, whereas the siliciclastic component decreases with distance offshore. The siliciclastic/carbonate transition of the investigated area is characterized by a narrow transition with no inter-fingering of the two facies. The lack of inter-fingering of the two facies suggests that there is a limited offshore transport of land-derived sediments. This is further supported by the drogue experiment results, which shows that the predominant surface current flows northward irrespective of the tidal phase Tanzania Journal of Science Vol. 32 (1) 2006: pp. 37-5

Morphodynamics of the Manyema tidal delta at Kunduchi, Tanzania

The prevailing northward longshore drift of beach sand on the northern part of Msasani Bay, north of Dar es Salaam, is interrupted at Kunduchi by the tidal flushing of Manyema Creek, a mangrove ecosystem partially developed for salt production. Shoreline changes around the creek mouth in recent decades have eroded coastal land and destroyed buildings, prompting stakeholders to construct protective groynes and revetments. Sand is transported across the delta by the interaction of two forcing processes – currents of water flushing the creek in response to tidal variation; and (generally) currents generated by wind-driven waves according to the monsoon season. Study of the sand morphology of the creek and delta platform together with time-series satellite imagery has permitted demarcation of the respective sand transport pathways and of morphodynamic changes on the delta over the last decade. The sand transport regime has promoted erosion of the shore to the south of the creek mouth and has led to a spasmodic delivery of sand to beaches north of the channel. Attempts to stabilise the shore around the creek mouth are described and their effectiveness evalutated

The population biology of the living coelacanth studied over 21 years

Between 1986 and 2009 nine submersible and remote-operated vehicle expeditions were carried out to study the population biology of the coelacanth Latimeria chalumnae in the Comoro Islands, located in the western Indian Ocean. Latimeria live in large overlapping home ranges that can be occupied for as long as 21 years. Most individuals are confined to relatively small home ranges, resting in the same caves during the day. One hundred and forty five coelacanths are individually known, and we estimate the total population size of Grande Comore as approximately 300–400 adult individuals. The local population inhabiting a census area along an 8-km section of coastline remained stable for at least 18 years. Using LASER-assisted observations, we recorded length frequencies between 100 and 200 cm total length and did not encounter smaller-bodied individuals (\100 cm total length). It appears that coelacanth recruitment in the observation areas occur mainly by immigrating adults. We estimate that the mean numbers of deaths and newcomers are 3–4 individuals per year, suggesting that longevity may exceed 100 years. The domestic fishery represents a threat to the long-term survival of coelacanths in the study area. Recent changes in the local fishery include a decrease in the abundance of the un-motorized canoes associated with exploitation of coelacanths and an increase in motorized canoes. Exploitation rates have fallen in recent years, and by 2000, had fallen to lowest ever reported. Finally, future fishery developments are discussed

Marine robots for coastal ocean research in the Western Indian Ocean

Marine robots have the potential to enhance WIO marine research to improve regional adaptation to the challenges presented by climate change by providing enhanced research capacity that bypasses the requirement for expensive infrastructure, such as large research vessels. This paper tests this potential and assesses the readiness of WIO communities to adopt autonomous technologies to meet its marine research priorities. We apply a range of analyses to a marine robots case study undertaken in waters around the island of Pemba, part of the Zanzibar archipelago, in Tanzania in 2019. The campaign formed part of a multinational project focused on increasing WIO capacity to meet food security and ocean sustainability challenges. A community engagement programme with six Tanzanian coastal communities resulted in positive changes in attitudes towards marine robots with reported increases in understanding and acceptance of such technologies. Suspicion of the robots was reduced and a lower risk of removing operational equipment was recorded following the provision of educational material. Cost, risk and benefit analysis shows that marine robots are perceived to provide high level benefits, but come at a high cost that is difficult to achieve using national or regional funding. An assessment of the capacity of WIO marine institutes to adopt such technologies shows that prior to this work, few skills or infrastructure related to marine robots were available to researchers and further confirmed that funding opportunities were perceived to be largely unavailable at institutional, national, regional or international levels. Responses from regional partners following completion of the case study however, revealed an uplift in perceived capacity, particularly related to access to infrastructure and expertise as well as support and opportunities for funding at each level. The presented case study is shown to have been a valuable demonstrator of the benefits of using marine robots to meet WIO coastal ocean research requirements and regional capacity was shown to be substantially increased within the broad range of marine institutes surveyed throughout the case study period. This study demonstrates that taking early steps towards adopting marine autonomous robots has increased WIO regional marine research capacity and increased the confidence and willingness of local researchers to seek alternative solutions to ongoing marine research challenges. Recommendations for future action that will continue to increase the capacity and readiness for regional adoption of marine robots include investment at local, national and regional levels to provide accessible training opportunities and to facilitate regional and international collaborations; investment in a regional hub, or centre of excellence for marine robotic technology; early adoption of newly emerging smaller, cheaper autonomous technologies; investment in local skills and support facilities to aid local buy-in and acceptance while supporting regional capacity

The evolving SARS-CoV-2 epidemic in Africa: insights from rapidly expanding genomic surveillance

Investment in SARS-CoV-2 sequencing in Africa over the past year has led to a major increase in the number of sequences generated, now exceeding 100,000 genomes, used to track the pandemic on the continent. Our results show an increase in the number of African countries able to sequence domestically, and highlight that local sequencing enables faster turnaround time and more regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and shed light on the distinct dispersal dynamics of Variants of Concern, particularly Alpha, Beta, Delta, and Omicron, on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve, while the continent faces many emerging and re-emerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Will Africans take COVID-19 vaccination?

The economic and humanistic impact of COVID-19 pandemic is enormous globally. No definitive treatment exists, hence accelerated development and approval of COVID-19 vaccines, offers a unique opportunity for COVID-19 prevention and control. Vaccine hesitancy may limit the success of vaccine distribution in Africa, therefore we assessed the potentials for coronavirus vaccine hesitancy and its determinants among Africans. An online crosssectional African-wide survey was administered in Arabic, English, and French languages. Questions on demographics, self-reported health status, vaccine literacy, knowledge and perception on vaccines, past experience, behavior, infection risk, willingness to receive and affordability of the SARS-COV-2 vaccine were asked. Data were subjected to descriptive and inferential statistics. A total of 5,416 individuals completed the survey. Approximately, 94% were residents of 34 African countries while the other Africans live in the Diaspora. Only 63% of all participants surveyed were willing to receive the COVID-19 vaccination as soon as possible and 79% were worried about its side effects. Thirty-nine percent expressed concerns of vaccine-associated infection. The odds of vaccine hesitancy was 0.28 (95% CI: 0.22, 0.30) among those who believed their risk of infection was very high, compared to those who believed otherwise. The odds of vaccine hesitancy was one-fifth (OR = 0.21, 95% CI: 0.16, 0.28) among those who believed their risk of falling sick was very high, compared to those who believed their risk of falling very sick was very low. The OR of vaccine hesitancy was 2.72 (95% CI: 2.24, 3.31) among those who have previously refused a vaccine for themselves or their child compared to counterparts with no self-reported history of vaccine hesitancy. Participants want the vaccines to be mandatory (40%), provided free of charge (78%) and distributed in homes and offices (44%). COVID-19 vaccine hesitancy is substantial among Africans based on perceived risk of coronavirus infection and past experiences.http://www.plosone.orgam2022Veterinary Tropical Disease

Will Africans take COVID-19 vaccination?

The economic and humanistic impact of COVID-19 pandemic is enormous globally. No definitive treatment exists, hence accelerated development and approval of COVID-19 vaccines, offers a unique opportunity for COVID-19 prevention and control. Vaccine hesitancy may limit the success of vaccine distribution in Africa, therefore we assessed the potentials for coronavirus vaccine hesitancy and its determinants among Africans. An online cross-sectional African-wide survey was administered in Arabic, English, and French languages. Questions on demographics, self-reported health status, vaccine literacy, knowledge and perception on vaccines, past experience, behavior, infection risk, willingness to receive and affordability of the SARS-COV-2 vaccine were asked. Data were subjected to descriptive and inferential statistics. A total of 5,416 individuals completed the survey. Approximately, 94% were residents of 34 African countries while the other Africans live in the Diaspora. Only 63% of all participants surveyed were willing to receive the COVID-19 vaccination as soon as possible and 79% were worried about its side effects. Thirty-nine percent expressed concerns of vaccine-associated infection. The odds of vaccine hesitancy was 0.28 (95% CI: 0.22, 0.30) among those who believed their risk of infection was very high, compared to those who believed otherwise. The odds of vaccine hesitancy was one-fifth (OR = 0.21, 95% CI: 0.16, 0.28) among those who believed their risk of falling sick was very high, compared to those who believed their risk of falling very sick was very low. The OR of vaccine hesitancy was 2.72 (95% CI: 2.24, 3.31) among those who have previously refused a vaccine for themselves or their child compared to counterparts with no self-reported history of vaccine hesitancy. Participants want the vaccines to be mandatory (40%), provided free of charge (78%) and distributed in homes and offices (44%). COVID-19 vaccine hesitancy is substantial among Africans based on perceived risk of coronavirus infection and past experiences

Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017

Background: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. Methods: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories. Findings: From 1950 to 2017, TFRs decreased by 49·4% (95% uncertainty interval [UI] 46·4–52·0). The TFR decreased from 4·7 livebirths (4·5–4·9) to 2·4 livebirths (2·2–2·5), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83·8 million people per year since 1985. The global population increased by 197·2% (193·3–200·8) since 1950, from 2·6 billion (2·5–2·6) to 7·6 billion (7·4–7·9) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2·0%; this rate then remained nearly constant until 1970 and then decreased to 1·1% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2·5% in 1963 to 0·7% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2·7%. The global average age increased from 26·6 years in 1950 to 32·1 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59·9% to 65·3%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1·0 livebirths (95% UI 0·9–1·2) in Cyprus to a high of 7·1 livebirths (6·8–7·4) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0·08 livebirths (0·07–0·09) in South Korea to 2·4 livebirths (2·2–2·6) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0·3 livebirths (0·3–0·4) in Puerto Rico to a high of 3·1 livebirths (3·0–3·2) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2·0% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger. Interpretation: Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress