Hippopotamus Amphibious Research Articles

Population status and habitat suitability of the vulnerable common hippopotamus (Hippopotamus amphibius) in the Dhidhessa Wildlife Sanctuary, Southwestern Ethiopia

Common hippopotamuses (Hippopotamus amphibious) are among the top five herbivorous animals in Africa. Despite being listed as a vulnerable species by the International Union for Conservation of Nature, they are a common mammal in Ethiopia's protected areas, lakes, rivers, and marshes. However, there is insufficient data to evaluate status of the population and habitat compatibility across the most of the country. The aim of this research was to ascertain the population size of hippos and the suitability of its habitat in the Dhidhessa Wildlife Sanctuary (DWS) in southwest Ethiopia. The study was conducted between 2021 and 2022. To estimate the population size, the total count procedures were employed. The adaptability of each habitat for hippos was determined using the multi-ring buffer analysis in Arc GIS 10.2. A total of 231 and 133 hippos were observed during both the dry and wet seasons, respectively. Of the surveyed individuals, 62.08 % were adults, 20.88 % were under-adults, and 17 % were young. More hippos (45.1%) were observed in the savanna grassland during the rainy season. Subsequently, the hippos (50.6%) relocated to the riverine forest in the dry season. Thus, the habitats in DWS and their environs were determined to range from most suitable to unsuitable for hippos. The results showed that 58.31% of the regions were unsuitable, 18.49% were moderately suitable, and 23.18 % were highly suitable for hippos grazing. 7.95% of the research area slope was suitable, 26.32 % moderate and 65.72% not suitable and 19.8% was considered most suitable for human interference, 46.3% was severely disturbed, and 33.9% was moderately affected. Based on the current investigation, it has been determined that human interference in hippos’ habitats is significant. In order to protect the hippos’ habitats from excessive human activities and their impacts, a buffer should be created around the DWS area.

Medium and large-sized mammals in human-dominated landscape of the former Dhidhessa wildlife sanctuary, Western Ethiopia

Abstract Assessment of medium- and large-sized mammals’ species diversity, abundance, distribution, and habitat association is necessary to promote their conservation measures. The study was conducted in the former Dhidhessa wildlife sanctuary (FDWS), to assess the medium- and large-sized mammals’ composition, distribution, and diversity. Transect lines were used to collect the data. A total of 1,146 ± 91 individuals belonging to 25 species, seven orders, and 14 families were recorded. Among these, 607 ± 186.5 (52.97%) were recorded during the wet season, whereas 539 ± 144.5 (47.03%) during the dry season. The order Carnivora was the most diverse one, followed by Artiodactyla and Primates, respectively, while Rodentia, Hyracoidea, Tubulidentata, and Lagomorpha were the least diverse orders. Olive baboon (Papio anubis) was the most abundant species (19.2%), followed by Hippopotamus (Hippopotamus amphibious) (17.63%) and Vervet monkey (Chlorocebus aethiops) (13.18%). Species diversity was higher in the savanna-wooded than in the riverine forest during both the wet (H’ = 2.72, Fisher’s alpha = 6.33) and dry (H’= 2.79, Fisher’s alpha = 6.26) seasons. Species evenness was higher in the savanna-wooded habitat than in the riverine forest habitat during both the wet (J’ = 0.87 and J’ = 0.77, respectively) and dry (J’ = 0.9 and J’ = 0.80, respectively) seasons. The highest similarity in species composition was between the wet and dry seasons in the riverine forest habitat (SI = 85.58%). The lowest similarity was recorded between the dry and wet seasons of the riverine forest and the wet season of the savanna wooded habitat (SI = 45.46% and SI = 46.49%, respectively). The study suggests that mammals are at risk of anthropogenic factors in the area. So, an urgent conservation measure that involves the participation of the local community has paramount significance for the sustainable conservation of mammals in the former Dhidhessa wildlife sanctuary.

Knowledge and Perceptions of Local People Towards the Hippopotamus, Hippopotamus Amphibious and its Conservation: Insights from Ghana

Knowledge and Perceptions of Local People Towards the Hippopotamus, <i>Hippopotamus Amphibious</i> and its Conservation: Insights from Ghana

Tissue distribution of angiotensin-converting enzyme 2 (ACE2) receptor in wild animals with a focus on artiodactyls, mustelids and phocids

Natural cases of zooanthroponotic transmission of SARS-CoV-2 to animals have been reported during the COVID-19 pandemic, including to free-ranging white-tailed deer (Odocoileus virginianus) in North America and farmed American mink (Neovison vison) on multiple continents. To understand the potential for angiotensin-converting enzyme 2 (ACE2)-mediated viral tropism we characterised the distribution of ACE2 receptors in the respiratory and intestinal tissues of a selection of wild and semi-domesticated mammals including artiodactyls (cervids, bovids, camelids, suids and hippopotamus), mustelid and phocid species using immunohistochemistry. Expression of the ACE2 receptor was detected in the bronchial or bronchiolar epithelium of several European and Asiatic deer species, Bactrian camel (Camelus bactrianus), European badger (Meles meles), stoat (Mustela erminea), hippopotamus (Hippopotamus amphibious), harbor seal (Phoca vitulina), and hooded seal (Cystophora cristata). Further receptor mapping in the nasal turbinates and trachea revealed sparse ACE2 receptor expression in the mucosal epithelial cells and occasional occurrence in the submucosal glandular epithelium of Western roe deer (Capreolus capreolus), moose (Alces alces alces), and alpaca (Vicunga pacos). Only the European badger and stoat expressed high levels of ACE2 receptor in the nasal mucosal epithelium, which could suggest high susceptibility to ACE2-mediated respiratory infection. Expression of ACE2 receptor in the intestinal cells was ubiquitous across multiple taxa examined. Our results demonstrate the potential for ACE2-mediated viral infection in a selection of wild mammals and highlight the intra-taxon variability of ACE2 receptor expression, which might influence host susceptibility and infection.

Effectiveness of using drones and convolutional neural networks to monitor aquatic megafauna

AbstractAquatic megafauna are difficult to observe and count due to the inaccessibility and issues of detectability. Traditional transect and helicopter counts are useful for obtaining population estimates, but they often have logistical and cost limitations. The recent proliferation of drone technology offers an innovative way of surveying animal populations. However, data collected from drones are hindered by an analysis bottleneck that increases the time needed to process them. Convolutional Neural Networks (CNNs) are an emerging category of deep learning that can automate this data analysis process. Here, we compare traditional methods with drone surveys, by detecting and counting Nile crocodiles (Crocodylus niloticus) and common hippopotami (Hippopotamus amphibious). We evaluate the utility of CNNs for object detection and quantification in complex environments. Drone counts were more accurate than traditional methods; identifying 21% more crocodiles. Where vegetation was open, hippo counts with a drone showed a similar pattern (identifying 43% more). When vegetation was dense the drone produced less‐accurate population estimates than traditional methods. CNN accuracy was limited (85%) due to the reduced training dataset available for the CNN. However, with an expanded data set, object detection is likely to be more accurate, making it more applicable for expedited and automated data analysis.

Impacts of habitats and seasons on mammalian diversity and distribution in the Faragosa-Fura landscape, Gamo Zone, Southern Ethiopia

ABSTRACT In Ethiopia, most of the studies on mammals have focused on single species and protected areas. This survey investigated the impacts of habitats and seasons on the medium and large-sized mammals’ diversity and distribution in a human-dominated landscape. This survey was conducted using 36 systematically distributed transect lines within stratified habitat types. A total of 685 records belonging to 21 species, six orders, and 13 families were identified, including globally vulnerable Panthera leo, Panthera pardus, and Hippopotamus amphibious. Overall, Papio anubis and Chlorocebus aethiops were the dominant species recorded in the area. Except for three species, all species encountered in the three habitats are subsets of the species recorded in the grassland. The species record frequency was highest in the forest. The dry season characterized by a higher frequency of records but by lower species richness than the wet season. In general, the study area is potential for mammalian species conservation in Ethiopia.

Activity and Pool Use in Relation to Temperature and Water Changes in Zoo Hippopotamuses (Hippopotamus amphibious).

Simple SummaryThe following study examined the behaviors and water vs. land use of an outdoor exhibit by three zoo hippos. Behavioral observations were correlated with water temperatures at the exhibit, and compared to the number of days (0, 1, or 2 days) since the water within the outdoor pool had been dumped and refilled. The water changing of the pools had little effect on either the behaviors or pool use itself by the hippos. Water temperatures affected both the behaviors and pool use by the hippos, with warmer water temperatures being directly correlated with greater activity and overall pool use. The results suggest that temperature, rather than water change, was the more important factor in increasing overall pool use and general activity for the exhibited hippos.In the wild, hippopotamuses spend much of their daily activity in the water. In zoos, it is less clear the extent to which hippos spend time in the water. We examined how much time Woodland Park Zoo’s three hippos spent in their outdoor pool, based on: (a) temperature of the pool water, and (b) when the pool water was changed (approximately three times a week). Several digital temperature data loggers collected water and air temperature readings once every hour for six months. We correlated the water temperature readings with several behaviors the hippos could engage in, where the hippos were on exhibit (pool vs. land), and how many days it had been since a dump (0, 1, or 2 days). The results indicated that water changes had little effect on pool usage, while increasing water temperatures resulted in both increased activity and pool use. The results are discussed in terms of how these findings relate to wild hippo activity, current knowledge of zoo-housed hippo welfare, and future directions for zoo-housed hippo welfare and research.

Perception Assessment of the Impact of Human Activities on Stubbs Creek Forest Reserve, Akwa Ibom State, Nigeria

Perception assessment of the impacts of human activities on Stubbs Creek Forest Reserve (SCFR) which is located between latitude 4°32'N and 4°40'N and longitude 7°48'E and 8°20'E (Figure 1) distributed into four Local Government Areas-Eket, Esit Eket, Ibeno and Mbo of Akwa Ibom State was carried out. Structural questionnaires to extract the common types of useful plants and animals, status of the protected area, derivable benefits and ways of preserving the SCFR were ministered to Chiefs Priests, Local Chiefs, Elderly People and Farmers who lived at least twenty years in the areas. Convenient sampling method was used to randomly select fifty respondents for the study. Descriptive statistics to summarize feedbacks from respondents presented in the form of tables, charts and histogram in line with the SCFR anthropogenic activities assessment indicators showing percentages and frequencies of such response was employed for data analyses and presentation. The results showed that the Stubbs Creek Forest Reserve have been disturbed and degraded due to uncontrolled human activities. Endangered fauna species including the Giraffa camelopardalis(Giraffe), Hippopotamus amphibious (Hippopotamus), Loxodonta africana (Elephant), Hynas, Kangaroo, Pantherpardus (Leopard), Panther leo (Lion), Porcupine and Tiger were last seen between twenty and thirty five years ago in the forest while some useful plants of huge economic and medicinal values like Irvingia gabonensis(Bush mango) Tetrapleura itraptera, Gambeya albidum, Raphia hookeri (Rafia palm), Garcinia cola (Bitter kola) and Dacryodes edulis (Native pear) etc were last observed about eleven to twenty years ago. The study further revealed that Monkeys and Alligators are still very common in the Forest Reserve. It, therefore, recommends the strengthening and enforcement of regulatory controls on the use of SCFR by relevant authorities and alternative source of firewood to reduce anthropogenic abuses and protect the rich resources of the forest from extinction.

Spatio-temporal epidemiology of anthrax in Hippopotamus amphibious in Queen Elizabeth Protected Area, Uganda.

BackgroundAnthrax is a zoonotic disease primarily of herbivores, caused by Bacillus anthracis, a bacterium with diverse geographical and global distribution. Globally, livestock outbreaks have declined but in Africa significant outbreaks continue to occur with most countries still categorized as enzootic, hyper endemic or sporadic. Uganda experiences sporadic human and livestock cases. Severe large-scale outbreaks occur periodically in hippos (Hippopotamus amphibious) at Queen Elizabeth Protected Area, where in 2004/2005 and 2010 anthrax killed 437 hippos. Ecological drivers of these outbreaks and potential of hippos to maintain anthrax in the ecosystem remain unknown. This study aimed to describe spatio-temporal patterns of anthrax among hippos; examine significant trends associated with case distributions; and generate hypotheses for investigation of ecological drivers of anthrax.MethodsSpatio-temporal patterns of 317 hippo cases in 2004/5 and 137 in 2010 were analyzed. QGIS was used to examine case distributions; Spearman’s nonparametric tests to determine correlations between cases and at-risk hippo populations; permutation models of the spatial scan statistics to examine spatio-temporal clustering of cases; directional tests to determine directionality in epidemic movements; and standard epidemic curves to determine patterns of epidemic propagation.Key findingsResults showed hippopotamus cases extensively distributed along water shorelines with strong positive correlations (p<0.01) between cases and at-risk populations. Significant (p<0.001) spatio-temporal clustering of cases occurred throughout the epidemics, pointing towards a defined source. Significant directional epidemic spread was detected along water flow gradient (206.6°) in 2004/5 and against flow gradient (20.4°) in 2010. Temporal distributions showed clustered pulsed epidemic waves.ConclusionThese findings suggest mixed point-source propagated pattern of epidemic spread amongst hippos and points to likelihood of indirect spread of anthrax spores between hippos mediated by their social behaviour, forces of water flow, and persistent presence of infectious carcasses amidst schools. This information sheds light on the epidemiology of anthrax in highly social wildlife, can help drive insight into disease control, wildlife conservation, and tourism management, but highlights the need for analytical and longitudinal studies aimed at clarifying the hypotheses.

Role of Food Insecurity in Outbreak of Anthrax Infections among Humans and Hippopotamuses Living in a Game Reserve Area, Rural Zambia.

In September 2011, a total of 511 human cases of anthrax (Bacillus anthracis) infection and 5 deaths were reported in a game management area in the district of Chama, Zambia, near where 85 hippopotamuses (Hippopotamus amphibious) had recently died of suspected anthrax. The human infections generally responded to antibiotics. To clarify transmission, we conducted a cross-sectional, interviewer-administered household survey in villages where human anthrax cases and hippopotamus deaths were reported. Among 284 respondents, 84% ate hippopotamus meat before the outbreak. Eating, carrying, and preparing meat were associated with anthrax infection. Despite the risk, 23% of respondents reported they would eat meat from hippopotamuses found dead again because of food shortage (73%), lack of meat (12%), hunger (7%), and protein shortage (5%). Chronic food insecurity can lead to consumption of unsafe foods, leaving communities susceptible to zoonotic infection. Interagency cooperation is necessary to prevent outbreaks by addressing the root cause of exposure, such as food insecurity.

Awareness and attitudes towards anthrax and meat consumption practices among affected communities in Zambia: A mixed methods approach.

BackgroundIn Zambia, human anthrax cases often occur following cases of animal anthrax. Human behaviour has been implicated in this transmission. The objective of the study was to explore human behavioural patterns that may contribute to outbreaks of anthrax among affected communities.MethodsA mixed methods study was conducted in four districts of Zambia from November 2015 to February 2016. A cross sectional survey involving 1,127 respondents, six focus group discussions and seven key informant interviews with professional staff were conducted. Descriptive statistics on socio-demographic characteristics, awareness of anthrax, attitudes towards cattle vaccination and risk factors for anthrax and vaccination practices were run using STATA 12 for analysis.ResultsOverall, 88% of respondents heard about anthrax, 85.1% were aware that anthrax is transmitted by eating infected meat and 64.2% knew that animals and humans can be infected with anthrax. However, qualitative data suggested that awareness of anthrax varied across communities. Qualitative findings also indicated that, in Western and Muchinga provinces, human anthrax was transmitted by eating infected beef and hippo (Hippopotamus amphibious) meat, respectively.Although survey data indicated that 62.2% of respondents vaccinated their animals, qualitative interviews and annual vaccination reports indicated low vaccination rates, which were attributed to inadequate veterinary service provision and logistical challenges. While 82% of respondents indicated that they reported animal deaths to veterinary officers, only 13.5% of respondents buried infected carcasses. Majority (78.1%) of respondents either ate, sold or shared meat from dead animals with other community members. Poverty, lack of access to meat protein and economic reasons were cited as drivers for consuming infected meat.ConclusionsHealth education campaigns must be intensified to reduce the risk of human exposure. Veterinary extension services should be strengthened and cold chain facilities decentralized in order to improve accessibility to anthrax vaccine. It is also important to involve the affected communities and collaborate with other disciplines in order to effectively tackle poverty, improve veterinary services and address inherent meat consumption practices within the communities.

Habitat suitability analysis for hippopotamus (H. amphibious) using GIS and remote sensing in Lake Tana and its environs, Ethiopia

This research was carried out from October 2013 to May 2014. Hippopotamus amphibious is a mammalian species distributed in different lakes and rivers where ecological requirements are fulfilled for its survival. Lake Tana and its environs are home to Hippopotamus amphibious. The species is identified as vulnerable worldwide due to habitat loss and poaching. However, despite its vulnerability, there is no research conducted regarding the species, and its environmental requirements in Ethiopia. Therefore, the main objective of this study was to carryout habitat suitability analysis and find out suitable habitat sites of hippopotamus within the Lake Tana and its environs using the integration of GIS and remote sensing techniques. The softwares such as, Arc GIS10.2, ERDAS IMAGINE2010, and Virtual satellite image downloader were used in this research. The data used were SPOT image of 2012 of the study area, bathymetric data of Lake Tana, DEM, Google Earth data and GCP. Running a suitability model requires estimation of weights by expertise for each individual criterion on GIS software. Thus, the habitats in Lake Tana and its environs ranging from most suitable to not suitable for hippopotamus were identified. It was shown that 50.88% of the areas under study was highly disturbed and became unsuitable to hippopotamus, 42.29% of the areas were moderately disturbed, and only 1.81% of the areas were revealed to be undisturbed. As the study result showed that in and around Lake Tana, a human factor was considered to be outweighing the physical factors to minimize the habitat for the aforementioned animal. The results revealed that only 22.54% of the study areas were identified as most suitable for the animal under study of which the large portions of the areas are located at the backside of settlements which are not easily accessible by the species, while 40.5% of the areas were found to be moderately suitable, and 36.96% were unsuitable habitats for hippopotamus. Based on the findings of the present study it was concluded that there was high interference of human being in the habitats of hippopotamus especially at the shores of the lake since the land were looked-for agricultural activities. Therefore, too much proximity of human activities in identified hippopotamus habitats have to be protected and conservation buffer surrounding the Lake has to be developed.

Seroprevalence of Toxoplasma gondii infection in zoo and domestic animals in Jiangxi Province, China.

Toxoplasma gondii is a zoonotic protozoan parasite that infects a wide range of warm-blooded animals throughout the world. In the present study, antibodies to T. gondii were determined using a commercial indirect hemagglutination (IHA) test in wild animals in a zoo. Three of 11 giraffes (Giraffa camelopardalis) (27%), 1 of 5 wolves (Canis lupus laniger) (20%), 1 of 6 hippopotamuses (Hippopotamus amphibious) (17%), and 2 of 9 tundra swans (Cygnus columbianus) (22%) were found to be positive. No antibodies were detected in leopards (Panthera pardus), wild geese (Anser cygnoides), and Eastern grey kangaroos (Macropus giganteus). Domestic species from 13 counties of Jiangxi Province, China were also investigated by an indirect hemagglutination (IHA) test. Thirty-five of 340 goats (10%), 94 of 560 water buffaloes (17%), and 4 of 35 cattle (11%) were found to be seropositive. This is the first report of T. gondii infection in animals kept in zoos and domestic animals in this province.

Morpho/Proteomic Comparative between High Grade Pleomorphic Sarcoma and Metastasis Diagnosed in an Old Captive Common Hippo

Old age is a risk factor for cancer development in humans and animals, and studies have shown that tumors in animals are acceptable models for studying human cancers, considering the similarities between their factors. This work was conducted in a 53-year-old captive female common hippo (Hippopotamus amphibious) with a left leg tumor and metastatic mass. Histopathological and immunohistochemical analyses were carried out with a final diagnosis of a high grade pleomorphic sarcoma. A proteomic study using mass spectrometry was added in order to identify further aspects of the primary tumor and metastasis which could improve our understanding, and each tissue showed a proteomic profile indicative of its pathologic state with significant differences between healthy tissue, primary and metastatic tumors. Low levels of β-actin in primary tumors were identified, and this may be associated with a possible consequence of cytoskeleton dynamic modification. In metastatic tissue, these dynamics may be affected by the presence of HSP chaperone 60.

CEREBELLAR AND MESENCEPHALON NEOPLASIA IN A NILE HIPOPPOTAMUS (HIPPOPOTAMUS AMPHIBIOUS).

A 52-yr-old female Nile hippopotamus ( Hippopotamus amphibious ) was presented for acute onset anorexia, depression, lethargy, instability, and weakness in the pelvic limbs. Clinical signs were rapidly progressive, despite empiric therapy with anti-inflammatory medications, resulting in the death of the animal. Gross necropsy evaluation revealed two tan, firm masses in the cerebellum and mesencephalon and a single mass in the right cranial adrenal gland. All three masses had a similar histologic morphology, and immunohistochemical investigation confirmed the general diagnosis of an adenocarcinoma, but the exact cell of origin remains unclear. In addition, there was evidence of neuroendocrine differentiation in the adrenal gland and not in the brain. These findings suggest either two distinct neoplastic populations or a metastasizing adenocarcinoma with focal endocrine differentiation. In dogs, anal sac and clitoral adenocarcinomas have been reported to undergo focal endocrine differentiation, and both can cause widespread metastasis while the primary lesion can be small. A small neoplasm of these glands may have been missed on gross examination.

RESULTS OF THE MEGAVEREBRATE ANALGESIA SURVEY: GIRAFFE AND HIPPOPOTAMUS.

Results of an online survey posted on the American Association of Zoo Veterinarians listserv examined the patterns of analgesic medication and pain management modalities used for captive giraffe and hippopotami. Compiled data included signalment, drugs administered, dosing regimens, subjective efficacy scores, ease of administration, and adverse events. Nineteen institutions exhibiting hippopotami ( Hippopotamus amphibious ) and pygmy hippopotami (Choeropsis liberiensis) and 45 exhibiting giraffe ( Giraffa camelopardalis spp.) responded. Phenylbutazone was the most-commonly administered nonsteroidal anti-inflammatory drug (NSAID), followed by flunixin meglumine, but doses varied widely. Eight institutions reported adverse events from NSAID administration. Tramadol was the most-commonly administered opioid followed by butorphanol. Only one adverse event was reported for opioids. Twenty-three of 45 institutions exhibiting giraffe utilized alternative analgesia methods including gabapentin, glucosamine-chondroitin, local anesthetics, and low level laser therapy. Six of 19 institutions exhibiting hippopotami administered omega 3-6 fatty acids, gabapentin, glucosamine-chondroitin, and α-2 adrenergics to provide analgesia. While all reporting zoological institutions administered similar drugs, there was substantial variation and diversity in both dosing regimens and frequencies, indicating the need for both preclinical and clinical studies supporting dosing regimens.

Conservation Challenge: Human-herbivore Conflict in Chebera Churchura National Park, Ethiopia

An investigation on human-herbivore conflict was carried out in CCNP between 2011 and 2012 in seven randomly selected villages (Chebera, Serri, Yora, Shita, Delba, Chuchra, Chewda) around the Park. A total of 312 household samples were identified for interview. Group discussion and field observation were also carried out. Among the respondents, the majority (83.9%) faced crop damage. African elephant (Loxodonta africana), Hippopotamus (Hippopotamus amphibious), African buffalo (Syncerus caffer), Desert warthog (Phacochoerus aethiopicus), Wild pig (Sus scrofa), Porcupine (Hystrix cristata), Vervet monkey (Cercopithecus aethiops) and Anubis baboon (Papio anubis) were identified as the most problematic animals in the area. However, buffalo, monkey and warthog were considered as the notorious pest. Crop damage and threats to human safety were the major problems encountered resulting in conflict between human and wildlife. Most respondents had a negative attitude towards the problem-posing animals. This will lead to a change in public attitude from one that supports wildlife conservation to sees wild herbivores as a threat and a potential negative consequence for wildlife conservation. Active measures have to be implemented to solve the problems and safeguard the future of the wildlife management in the park.

Population status of the common hippopotamus (Hippopotamus amphibius) in Luangwa River, Zambia

The population size of common hippopotamus, Hippopotamus amphibious in the Luangwa valley, Zambia was assessed for the period of 1976 to 2008. A comparison of historical data on population size for the period of 1952 to1975 was also made. Ecological carrying capacity (K) and carrying capacity band were estimated from data on population size. The river bank foot count method was used, which involved the counting of individuals and taking Global Positioning System (GPS) locations of hippopotamus schools. Ecological Carrying capacity (K) was 6,000 hippopotami and density at K was 35/km. The population was found to be oscillating within carrying capacity band of 2,000 individuals in eight (8) irregular cycles. From K, annual population changes were small and insignificant. A weak correlation was found between population size against time, suggesting a slow down in population growth from 1976 to 2008 (R2 = 0.22). The highest population size of 6,832 hippopotami and density of 42 was reached in 1984. The lowest was 4,765 hippopotami and density of 29/km recorded in 1978. Within the period of 1976 to 2008, the population oscillated between 5,000 and 7,000 individuals, which were symptomatic of a population at K. The slow down in population growth was attributed to environmental resistance. More studies are required to identify factors responsible for environmental resistance which is caused by the rise and fall in the hippopotamus population of the Luangwa River. Key words: Hippopotamus, ecological carrying capacity, oscillation.

Human–animal anthrax outbreak in the Luangwa valley of Zambia in 2011

There has been a reduction of incidences of anthrax in the developed countries but it is still a public health problem in the developing countries where communities live in interface areas with wildlife. An outbreak of anthrax in Hippopotamus amphibious was observed in Zambia. Following the death of hippopotamuses, suspected human cases were reported. The objective of this study was to isolate and confirm Bacillus anthracis and to determine the antimicrobial susceptibility for the management of the disease. Of the specimens collected, 29.4% (95% confidence interval [CI], 11.4-56.0) were from humans, 42.1% (95% CI, 21.1-66.0) were from hippopotamuses and 20.0% (95% CI, 6.61-44.3) from the soil were found to be positive were for B. anthracis. An antimicrobial susceptibility test revealed that all the isolates were found to be sensitive to the recommended antibiotics. The disease control was achieved by case management and by explaining to the communities that they should avoid contact with animals that die from unknown causes.

Fishery and the Tourism Potential of Agbokum Waterfalls, Nigeria

Species richness and human activities in natural environments are among the most important recreational needs. Monthly studies of aquatic fauna, artisanal fisheries and tourism characteristics was conducted during wet and dry seasons, over a two year period in the three landscapes along the 6817.7 m length of Agbokum waterfalls by using a close-ended pre-coded survey instrument. Through MANOVA analysis of the 1780 respondents we found strong positive association between peoples visits to the recreational areas and the type of landscape in which the respondents felt happy. People who felt happier in landscape dominated by waterfalls, visit the middle reaches of the river for outdoor recreation more often while people who feel happy in landscapes dominated by slow water current with an extensive wide area and floodplains, visit downstream reaches of the waterfalls more often. Activities performed more often along downstream reaches include fishing, bathing/swimming, boating and hunting while more frequent activities in the middle reaches (waterfalls) include taking photographs, picnics, enjoying nature, outing with family and friends, looking at view, resting and relaxing. A total of 5484 fish representing 22 species belonging to 16 genera from 9 families were sampled with 10 species being restricted to wet season and only 1 in the dry. The number of taxa and individuals present at upstream, midstream and downstream reaches were 16 (2003), 13 (1034), 17 (2447), respectively. Tilapia zillii, Clarias gariepinus and Labeo coubie dominated overall catch constituting 35.5%. Twenty five operational boats counted during the period of study, were only used downstream by 25 full-time fishermen, 87 part-time, 44 shoreline fishermen and 36 assistant fishermen. Common gears were the hook and line constituting 45.8%, cast and dip net (10.1%) bailing (8.7%), gill nets (7.3%), seine net (6.4%) Traps (5.5%), lift net (4.7%) Dip nets (0.9%), poisoning (2.8%), cutlass (3.3%) and spear (1%). Seasonally occurring aquatic fauna include crustaceans (Atya gaboneensis and Palaemon paucidens) (23.5%) oysters (Etheria elliptica) (15.4%), clams (Galacea paradoxa) (20.8%), Manatee (Trichechus senegalensis) (2.5), Hippopotamus amphibious (1.8%), Otter (Lutra macullicolis) (0.5%), Crocodyles (Crocodylus niloticus, Crocodylus cataphractus (Aligata) and Osteolaemus tetraspsis) (18.8%). The nile monitor (Varanus nilaticus), aquatic snake (Anoscopus sp), and three species of water turtle (Kimxys erosa, Pelumedusa sp and Peliosus sp) (21.6%). Relatively higher faunal densities and species richness in the upstream and downstream reaches coupled with waterfalls in middle reaches can makes Agbokum waterfalls a tourism destination if only management strategies include Legislation to conserve these natural resources.