Top PDF Abundance and Distribution of African Fish Eagles along Major Rivers in Gonarezhou National Park, Zimbabwe

Abundance and Distribution of African Fish Eagles

along Major Rivers in Gonarezhou National Park,

Zimbabwe

Abundance and Distribution of African Fish Eagles along Major Rivers in Gonarezhou National Park, Zimbabwe

Earlier studies have provided some valuable information on factors influencing the abundance and distribution of African fish eagles in the savannas. For example, Douthwaite (1992) studying the effects of water pollutants in the African fish eagle’s population of Lake Kariba, Zimbabwe, suggested that the population was limited more by the availability of suitable nesting trees than mercury or organic chlorine pollutants. Elsewhere, Harper et al. (2002), in a 13-year study of the African fish eagle population in Lake Naivasha, Kenya, showed that the population was limited by lack of available prey associated with eutrophication, perching tree availability and other factors linked to anthropogenic habitat alteration. In contrast, Mundy and Couto (2000) suggested that eutrophication may have played a role in high productivity by African fish eagles on the polluted Lake Chivero, Zimbabwe. Interestingly, the recorded density of African fish eagles in Gonarezhou is within the previously reported density range for river ecosystems (e.g., Krueger, 1997; Harper et al., 2002).
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Abundance and structure of African baobab (Adansonia digitata) across different soil types in Gonarezhou National Park, Zimbabwe

Abundance and structure of African baobab (Adansonia digitata) across different soil types in Gonarezhou National Park, Zimbabwe

influence local distribution and patterns of plant species [ 30 ]. A key to this focus was our observation that baobab com- munity in Gonarezhou tends to occur more densely along environmental gradient of soil group as influenced by the underlying geological soil substrates of granophyres. Malver- nia derived soil group type is likely less ideal for baobab abundance and recruitment. Our study results suggested that underlying geology which dictates soil group type is a key determinant for the pattern of baobab abundance, structure, and recruitment. This confirmed as was noted that, within southeastern Zimbabwe low altitude plains, variations in rainfall, altitude, and temperature are negligible, and conse- quently vegetation communities can be considered according to soil group types which generally change with variations in geological types [ 31 ].
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Local community perceptions on landscape change, ecosystem services, climate change, and livelihoods in Gonarezhou National Park, Zimbabwe

Local community perceptions on landscape change, ecosystem services, climate change, and livelihoods in Gonarezhou National Park, Zimbabwe

With regards to provisioning service, there are numerous products around the study area which directly or indirectly impact the livelihoods of the people within the area and beyond. The most important non-timber products obtained by the community are wild fruits and medicinal and cosmetic products from vegetation (Figure 7). For example, fruits such as “nyii” (Berchemia discolor) are popular in the community [40]. The other provisional ecosystem services that are highly available are cultivated crops and livestock. However, this has led to ecosystem services trade-offs. For example, the crops and overstocking of livestock have led to soil erosion and a decline in soil quality. However, more studies are required in the area to quantify the extent of this. With the presence of three major rivers, fish is also relatively available, but to a limited extent because conservation personnel in Gonarezhou enforce a restriction of bulk fishing. Nevertheless, despite the abundance of wild animals, these were not available since they are protected in the park and it is criminal to hunt and be seen with game meat. The wild animals are a provisional service because the community also sees them as a source of food [80]. Despite the boom in animal numbers, the community does not see how it benefits their livelihoods because conservation without impacting people’s livelihoods is meaningless to them. Sustainability 2020, 12, x FOR PEER REVIEW 12 of 21
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Relationships between termite (Macrotermes) mound distribution, plant diversity and large mammalian herbivory patterns in Gonarezhou National Park, Zimbabwe

Relationships between termite (Macrotermes) mound distribution, plant diversity and large mammalian herbivory patterns in Gonarezhou National Park, Zimbabwe

Termite species diversity has been shown to change along numerous environmental gradients: increasing as mean annual rainfall increases in the savanna (Buxton 1981, Davies et al. 2015), while conspicuously decreasing with increased levels of anthropogenic disturbance in tropical forests (Eggleton et al. 1996, 1997, Dosso et al. 2010). Termite diversity is always higher in intact forests compared to more disturbed anthropogenic land use areas, such as plantations (Attignon et al., 2005; Dosso et al., 2013). Sharp decreases in termite diversity have also been reported with increasing altitude (Gathorne-Hardy et al., 2001; Palin et al., 2011). As yet, there is a lack of consensus on the influence of fire (see Davies et al. 2010 for a review), with some studies finding no effect of long-term fire regimes (e.g. Davies et al. 2012), and others recording a decline in termite abundance immediately following fire (e.g. Dawes-Gromadzki 2007). Although geological variation has been shown to have an effect on vegetation heterogeneity (Venter et al. 2003), little is known about the landscape and point-scale relationships between termites and soil properties (Jones et al., 2010). Indeed, there is little information on how termite species composition varies in areas with different geologies (but see Wild 1975, Jones et al. 2010), resulting in a poor understanding of how termite diversity differs across landscapes. Where geology has been considered, the focus has been on the density and spatial distribution of mounds built by Macrotermes (Meyer et al. 1999, Davies et al. 2014b), excluding the majority of taxonomic and functional termite groups that do not build conspicuous mounds. To date, very little is known regarding how variation in geological substrate influences overall termite species diversity in savannas, especially at the landscape scale (but see Wild 1975).
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Wildlife tourism in Gonarezhou National Park, southeast Zimbabwe: opportunities for wildlife viewing

Wildlife tourism in Gonarezhou National Park, southeast Zimbabwe: opportunities for wildlife viewing

conservation and development in the rural communities of Southern Africa (Chiutsi, Mukoroverwa, Karigambe, & Mudzengi, 2011). CONCLUSION This study showed that the southern GNP apparently has some opportunities for wildlife viewing particularly along the tourist roads. This is in support of recent findings in GNP which suggest that populations of several large herbivore species are increasing (Dunham, van der Westhuizen, van der Westhuizen, & Gandiwa, 2010; Zisadza, et. al., 2010). It is however, possible with high levels of visitation and usage of the roads for wildlife viewing, it may result in some disturbance along the road to levels that would affect the wildlife species, hence the importance of continued monitoring of the park usage. Monitoring human impacts on wildlife however, can be challenging, since wildlife are mobile and engage in learned behaviour (e.g., Anderson, et al., 2010). There is need in the future to develop carrying capacities of the roads to ensure good wildlife viewing opportunities are always maintained for the park’s visitors. Park managers must continue to be attentive to these and other changes in human activity along the park roads. Additionally, park managers in GNP should manage the park to allow for the persistence of wildlife and maintenance of species diversity. Large herbivore represents the feature of PAs most important to tourists, and these species play a key role in attracting the bulk of visitors to parks (Lindsey, et al., 2007). Future studies should focus on wildlife abundance, distribution and behaviour along the park’s major tourist roads in the GNP.
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The distribution of an invasive species, clidemia hirta along roads and trails in Endau Rompin National Park, Malaysia

The distribution of an invasive species, clidemia hirta along roads and trails in Endau Rompin National Park, Malaysia

Even though undisturbed tropical rainforests have rarely suffered from invasion by alien species (Fine, 2002; Levine, 2000), Clidemia hirta (L.) D. Don. (Melastomataceae), which originated in South America, provides one exception, as it has colonized undisturbed tropical forests in Southeast Asia (Peters, 2001). C. hirta is a highly invasive plant presenting a conservation nuis- ance, and it is prevalent throughout the Pacific Ocean and Indian Ocean, including several islands (Cronk & Fuller, 1995; Rejma´nek, 1996; Wester & Wood, 1977). In Hawaii, C. hirta may be replacing endemic species that had been predominant, leading to their extinction (Wester & Wood, 1977). Both humans and wild animals have been implicated in the spread of C. hirta. Ground disturbance by wild pigs (Sus scrofa) has played a vital role in the establishment of C. hirta and other alien spe- cies in Hawaii (Smith, 1992). At Pasoh, in Peninsular Malaysia, the distribution of C. hirta was found to be related to soil disturbance by wild pigs and to openings in the canopy (Fujinuma & Harrison, 2012; Peters, 2001). Thus, canopy openness and soil disturbance appear to be the key factors affecting the distribution of C. hirta.
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Analyzing tree distribution and abundance in Yukon-Charley Rivers National Preserve: developing geostatistical Bayesian models with count data

Analyzing tree distribution and abundance in Yukon-Charley Rivers National Preserve: developing geostatistical Bayesian models with count data

Since our plots are effectively points (on the scale of the entire park) th a t are georeferenced using latitude and longitude, our d a ta are considered to be point-referenced, or geostatistical. A common way to model geostatistical d a ta is by assuming a correlation structure between points th a t decays continuously as a function of distance (Finley, Banerjee, and Carlin 2007). We assumed th a t these spatially correlated errors followed a m ultivariate normal distribution (thus creating Gaussian spatial process models), with a m ean of 0 and an exponential covariance function. This structure includes two spatial term s: a 2, which represents site specific variance, and ^, which describes the distance over which the spatial correlation decays as follows: ^ « 3/do, where d0 is effective distance. Once two sites are separated by d0, they are expected not to exhibit any residual spatial correlation. Here we are assuming isotropy, which means th a t spatial correlation is only dependent on the distance between two sites, w ithout a directional component. For geostatistical GLMs, the spatially correlated errors are added to the “m ean stru ctu re” , which is the linear p art of the model, before the link function is applied.
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Diversity and abundance of beetle at Kuala Kelapor, National Park, Malaysia

Diversity and abundance of beetle at Kuala Kelapor, National Park, Malaysia

precious natural reserve covers Pahang (2,477 km 2 ), Kelantan (1,013 km 2 ) and Terengganu (853 km 2 ) states in Peninsular Malaysia with a total land area of 4343 km 2 (DWNP 2000; Pakhriazad et al. 2009).The observed habitats include rivers, freshwater swamp, dipterocarp montane forests, lower montane forest, montane oak, montane ericaceous and upper montane forestand riparian forest (Tingga et al. 2012). Riverine ecosystem of Kuala Kelapor National Park covers three major rivers (Sungai Lebir, Sungai Terengganu and Sungai Tembeling) and many small rivers (Khan 1990). The highest peak ie. Gunung Tahan is found in Kuala Kelapor National Park. This complex ecosystem supports large mammals, small mammals, birds, amphibians, fishes, insects and plants (Siti-Hawa et al. 1985; Zulkiflee et al. 2012). The previous studies at Kuala Kelapor National Park were focused on Sumatran rhinos (Foose & Van Strien 1997), tigers (Kawanishi & Sunquist 2004), elephants (Saaban et al. 2011), large animals (Khan & Khan 1990), primates (Chivers 1990), mammals (Siti-Hawa et al. 1985), wild pigs (Othman 1990), small mammals (Lim et al. 1989; Liat & Anan 1990; Tingga et al. 2012), snakes (Liat et al. 1990), amphibians (Heang 1990), fishes (Zakaria-Ismail 1984; Mohd-Azham& Singh 2012; Farinordin et al. 2016) and birds (Siti-Hawa et al. 1985; Wells 1990; Saad et al. 2014). Moreover, different types of plants are also well studied too (Dransfield & Kiew 1990; Kiew 1990; Kochummen 1990; Ohba 1990).
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Modeling the spatial distribution of African buffalo (Syncerus caffer) in the Kruger National Park, South Africa

Modeling the spatial distribution of African buffalo (Syncerus caffer) in the Kruger National Park, South Africa

The current study was approved by the Animal Ethics Committee of the Faculty of Veterinary Science, University of Pretoria (Project No. V083-11). The KNP road network was chosen as the method to collect field data due to feasibility and costs associated with other sampling approaches. The public road network of KNP is irregular and therefore a random walk [ 28 ] design was used to collect field data rather than the more common quadrant or transect sampling approaches. Random route approaches are more com- monly used in sociological studies despite the potential for selection bias [ 29 ]. One data set was collected during the dry season (August 2012) and another during the wet season (January 2013). The KNP was divided into three areas (northern, central, and southern) for field data collection. Four locations were purposely selected within each KNP area that allowed for the most divergent starting locations ( Fig 2 ). The starting area for each sampling trip (August and January) was randomly selected and then the order of daily starting locations was also deter- mined randomly. It was necessary to stratify KNP into three areas for sampling to reduce the required distance to get to the next starting location after the completion of the daily sampling. A route was created from each starting location: a random number generator was used to determine turning direction (0-back, 1-forward, 2-left, 3-right) based on a map of the KNP public road network. Each starting location was assigned a numerical value and a random number generator was again used to determine the sequence of starting locations. Each start- ing location was used twice, thus producing a total of 24 routes. Each observation day con- sisted of a five-hour drive along the random route, which was determined prior to the sampling day using GIS maps. Data were collected when buffalo were observed within 250 m of the observation vehicle. Distance to the spotting vehicle was determined using a golf spot- ting scope (Binolux Golf Scope, Compass Industries, Inc., NY, USA) and buffalo numbers were manually counted. Additional data that were collected included the GPS location of the buffalo, herd composition (bachelor or mixed), time of day, temperature, humidity, baromet- ric pressure, visible water source, savanna type, and a subjective measure of vegetation density. A dense landscape was defined as an area that contained trees or shrubs covering 50% or more of the area adjacent to the road and in which the buffalo were situated. An open landscape was one in which 5% or less of the area of interest contained trees or shrubs. Data were also recorded at the start of daily sampling and at the end of each hour during sampling. Data col- lection during the January sampling was not completed due to flooding of KNP and the subse- quent closing of public roads.
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Distribution and abundance of small mammals in relation to habitat in Pureora Forest Park

Distribution and abundance of small mammals in relation to habitat in Pureora Forest Park

Summary: Populations of ship rats (Rattus rattus), Norway rats (R. norvegicus), feral house mice (Mus musculus), stoats (Mustela erminea), weasels (M. nivalis), and ferrets (M. furo) were sampled with killtraps every three months from November 1982 to November 1987 in logged and unlogged native forest and in exotic plantations of various ages at Pureora Forest Park, central North Island. Mice (n=522 collected) were fewest in unlogged native forest, more abundant in road edge cutover forest, and most abundant in a young (5-10 year old) plantation. Traps catching most mice were set in dense ground cover under a low, sparse canopy. Ship rats (n=1793) were absent from the young plantation, present but not abundant in older exotic forest, and abundant in all native forest regardless of logging history. Traps set on warmer, steeper sites caught most ship rats, and those set in early successional habitats caught fewest. There was a marked reciprocal relationship between the distributions of ship rats and of mice: the proportion of mice in the total catch of rodents decreased significantly at the least disturbed forest sites (P< 0.001). Most (81%) Norway rats (n=43) were caught in a single trap in unlogged native forest on the bank of a stream. Stoats (n=57) were most abundant in the older exotic plantations; weasels (n=16) in the young plantation and along road edges in native forest; and ferrets (n=11) in unlogged native forest. Hedgehogs (n=290) were common in unlogged native forest far from any roads and also in older exotic forest. Our data suggest that selective logging and conversion to exotics have different effects on each of the six species we monitored. We hypothesise that (1) selective logging is likely to stimulate temporary increases in the numbers of mice and weasels, but not rats or stoats, and (2) after conversion to exotic forest, mice and occasionally weasels will be abundant at first but will gradually be replaced by ship rats and stoats as the forest matures.
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Abundance and Fish Species Composition of Gerado and Dirma Rivers, South Wollo, Ethiopia

Abundance and Fish Species Composition of Gerado and Dirma Rivers, South Wollo, Ethiopia

In this study, four sampling sites were selected; two from each river (Table 1). Site selection was done by considering nature and velocity of the flowing river, interference by human beings and other farm animals and substrate type of the sediments and accessibility. Each sampling site was sampled twice at dry and twice in wet seasons. Gillnet of stretched mesh size of 6 - 10 cm were used to sample the fish by setting the net at deeper part of the river. Monofilament with meshes size of 20 mm was set on the rivers for one hour to sample small-sized fish species. Then, total length, weight of all specimens of fish was measured to the nearest cm and gm respectively. Picture of fish specimen was taken for each species. After taking the entire necessary information individual specimen was preserved with 4% formalin and was put in plastic jar and was transported to Wollo University, Biology department laboratory for further identification.
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Study of distribution and abundance of tsetse fly (glossina sp ) in gashaka gumti national park, Nigeria

Study of distribution and abundance of tsetse fly (glossina sp ) in gashaka gumti national park, Nigeria

Tsetse flies, of the genus Glossina are large biting and blood- feeding flies of great economic, veterinary, and medical importance, due to their ability to transmit African trypanosomiasis in humans and animals, they are cyclical vectors that transmit animal trypanosomiasis which constitute a significant barrier to the development of farming and food security in the regions of Africa where they are prevalent (Bouyer et al., 2013). Tsetse-transmitted trypanosomiasis occur in 38 sub-Saharan African countries with averages of 15,000 human cases and one million cattle deaths reported yearly, exposing over 70 million people and 160 million cattle to the risk of infection in the region , (OIE Terrestrial Manual, 2008). Tsetse flies are distributed over wide range of habitats covering about 10 million square kilometers of potential grazing and farming lands in sub-Saharan Africa (Kuzoe, 1993).
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Distribution of Vascular Plants along Altitudinal Gradients in Hoang Lien National Park, Vietnam

Distribution of Vascular Plants along Altitudinal Gradients in Hoang Lien National Park, Vietnam

DOI: 10.4236/ojf.2019.94023 408 Open Journal of Forestry communities are identified by topography such as mountainous slopes, expo- sures, slopes and peaks (Austrheim, 2002; Gottfried, Pauli, Reiter, & Grabherr, 1999; Grytnes & Beaman, 2006; Grytnes & Vetaas, 2002; Ninot & Ferré, 2008). According to Bussmann & Sharon (2006), the vegetation cover has changes in structure, species composition, dominant species group, and density of plant communities along elevation belts. Evaluating the relative importance of the factors that might determine elevational richness patterns remains challenging (Krömer, Acebey, Kluge, & Kessler, 2013). Among the factors of geometric con- straints, area and climate, altitude is one of the most important factors affecting species richness patterns in mountain ecosystems, because it has played an es- sential role in driving drastic changes in temperature, water availability as well as overall area (Beals, 1969; Bruun et al., 2006; Lee, Chun, Song, & Cho, 2012). The research results show that the correlation between species richness, plant com- munities with elevation, and changes of environmental factors by altitude is the cause of the diversity of habitats, abundance of plant communities and forma- tion of vegetation belts.
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Distribution and abundance of benthic macroinvertebrates and zooplankton in lakes in Kejimkujik National Park and National Historic Site of Canada, Nova Scotia

Distribution and abundance of benthic macroinvertebrates and zooplankton in lakes in Kejimkujik National Park and National Historic Site of Canada, Nova Scotia

it may be possible that a localized population of H. azteca has adapted to the acidic environment in the lakes in Kejimkujik National Park and National His- toric Site. A genetic study by Witt and Hebert (2000) examined populations of H. azteca from various loca- tions across North America and found a complex of at least seven species rather than a single species as pre- viously believed. grapentine and rosenberg (1992) also suggested that populations of H. azteca may have adapted to acidic conditions in some regions of Canada. interpretation of regional variation in H. azteca habi- tat associations and identification of their potential role in biological monitoring of lakes in this study area would benefit from an improved understanding of the geographic variation in their genetic profile and the consequences for their tolerance of acidic conditions. When we compared the relative proportions of iso - pods and amphipods across the 20 study lakes, we found that isopods were dominant in lakes with low pH and low calcium concentrations while amphipods were dominant in lakes with high pH and high calci- um concentrations. Both amphipods and isopods are photosensitive and avoid bright light by moving into crevices or under rocks, leaves, and roots (Covich and thorp 2001, page 791), where they are less exposed (complex substrates provide protection from preda- tion by fish and crayfish) (Covich and thorp 2001, page 791). the substrate in many of the study lakes consists of cobbles and boulders, which may partially explain the high abundance of these two taxa. Bivalvia and gastropoda
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Spatial distribution of 0+ juvenile fish in differently modified lowland rivers

Spatial distribution of 0+ juvenile fish in differently modified lowland rivers

A b s t r a c t . Juvenile 0+ fish communities in three adjacent stretches of two lowland rivers with different degrees of habitat modification were surveyed using electrofishing and evaluated as indicators of fish assemblage reproductive success and spatial distribution. Both rivers originally meandered through large flood plains, however both have been regulated and channelised, to a varying extent, during the last century. The first study stretch, the Czech stretch of the Morava River (69.4 – 92.8 r. km), was regulated by five weirs and completely separated from its floodplain. The second and third study stretches, the Slovak stretch of the Morava River (33.5 – 69.4 r. km) and the Dyje River (0 – 26.7 r. km), were not interrupted by weirs and their floodplain areas remain connected, though partially modified. The total number of 0+ fish species in all of the stretches recorded over three years was similar (22, 23 and 25 spp. resp.). The lowest value of the Shannon index of species diversity and the highest value of total relative density (CPUE) were documented in the Czech regulated-channelised stretch. Significant differences in species richness and relative density were documented among habitats.
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Movements of dead fish in rivers

Movements of dead fish in rivers

Water discharge at release and average water discharge in the period after release did not seem to impact distance drifted in either smolt or eel (Additional file  6). In eel, but not in smolt, high floods in the period after release seemed to result in the longest drift distances (Addi- tional file  6). However, impacts of water discharge are difficult to assess based on these data, since they include fish released at different sites, the sample sizes within groups are small, and site-specific effects may obscure the impact of water discharge. If we compare groups within each of the species that are released at the same site, but at different dates and, hence, different water dis- charges, this confirms that there is not a clear relation- ship between distance drifted and water discharge at and after release (Table 1).
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Field study site selection, species abundance and monthly distribution of anopheline mosquitoes in the northern Kruger National Park, South Africa

Field study site selection, species abundance and monthly distribution of anopheline mosquitoes in the northern Kruger National Park, South Africa

Among the nine species collected, An. quadriannulatus was found at four out of the five sites while An. coustani group was common at three sites (Malahlapanga, Sirheni bush camp and Louis se gat). Anopheles arabiensis was confined to Malahlapanga except in a few instances where one specimen was collected at Sirheni in February 2011, again in January 2012 and again in March 2012, and three specimens were collected from Louis se gat in March 2012 (Figure 3). The occurrence of An. merus was primar- ily limited to Matiovila and Mafayeni with the exception of two instances, November and December 2012, when specimens were unexpectedly collected in Malahlapanga. Anopheles squamosus and An. rufipes were confined to Malahlapanga. There was a significant difference in the dis- tribution of members of the An. gambiae complex across the sites (chi-square = 3095; df = 6; P < 0.05). Anopheles merus predominantly breeds at Matiovila and Mafayeni. These two sites contributed 98.6% of the total An. merus catches. Of all the An. arabiensis, 99.6% were collec- ted at Malahlapanga. Salinity tests of water samples from Mafayeni and Matiovila showed that the weight of sodium chloride equivalent was 12.4 g/l and 3.7 g/l, respectively. Table 1 Summary of anopheline mosquitoes collected from northern Kruger National Park, South Africa, between July 2010 and December 2012
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The Abundance of Anoa (Bubalus SP.) Plant at Bogani Nani Wartabone National Park

The Abundance of Anoa (Bubalus SP.) Plant at Bogani Nani Wartabone National Park

Kata Kunci: Kelimpahan, keanekaragaman, tumbuhan pakan, anoa, Bogani Nani Wartabone ABSTRACT Bogani Nani Wartabone National Park (TNBNW) is an important habitat for anoas, which represents genetic diversity of anoa species in the northern area of Sulawesi. Wild animals depend on their habitats for many things, including food. Food availability influences the growth and reproduction of any species. Food information is also important for area management as an input in habitat development activities, which are parts of in-situ conservation. The aim of this study was to investigate the types, abundance and diversity of anoa food plants in TNBNW. The study was conducted in three locations, namely Imandi Mountain, Gambuta Mountain and Sinombayuga Mountain ranging between 0 and 1600 mdpl elevations. Data were collected using line plot sampling method and food type observation was performed with plots size of 0.04 ha. Total observation plots in three research locations were 202, of which 90 plots were in Imandi Mountain and Gambuta Mountain, and 22 plots were in Sinombayuga Mountain. Data were analyzed descriptively and presented in tables. Food abundance was determined by total food plants found in every location. Natural plants food diversity used several indices, which were Margalef Richness, Shannon-Wiener Diversity Index and Evenness Index. The results showed that 35 species of food plants were identified. As many as 28 species of them including herbaceous plants, and seven species of woody plants. Some plant species have higher abundance, namely rofu (Elatostema sp.), rattan (Calamus sp.), and various types of fern.
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Mercury and Methylmercury Concentrations in Muscle Tissue of Fish Caught in Major Rivers of the Czech Republic

Mercury and Methylmercury Concentrations in Muscle Tissue of Fish Caught in Major Rivers of the Czech Republic

A total of 96 indicator fish (Leuciscus cephalus - males) were collected at the selected localities in 2007. The chub came from the twelve sites on eleven major rivers in the Czech Republic, i.e. Lužnice - Bechyně (river km 11), Otava - Topělec (river km 20), Sázava - Nespeky (river km 27.5), Berounka - Srbsko (river km 29), Vltava - Zelčín (river km 5), Labe - Obříství (river km 122), Ohře - Terezín (river km 3), Labe - Děčín (river km 21), Svratka - Židlochovice (river km 23), Dyje - Pohansko (river km 16), Morava - Lanžhot (river km 9.5), Odra - Bohumín (river km 9) (Fig. 1). River kilometres of the Labe sites (Obříství and Děčín) and Odra site (Bohumín) were measured from the border with Germany and Poland.
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Distribution, Abundance and Movement of Fish among Seagrass and Mangrove Habitats in Biscayne Bay

Distribution, Abundance and Movement of Fish among Seagrass and Mangrove Habitats in Biscayne Bay

shoreline (Serafy et al. 2003). The overall objective of this thesis is to determine distribution, abundance and movement patterns of fish in southern Biscayne Bay. This thesis is split into two chapters, each focusing on different habitats within the Bay. The first chapter focuses on understanding the predatory fish assemblage in two critical fish nursery areas (mangrove and seagrass beds). Although commonly believed that these two nursery areas harbor lower abundances of predators, this perception has been recently challenged with studies reporting significant piscivore assemblages and high predation rates (Baker and Sheaves 2005, Baker and Sheaves 2006, Dorenbosh et al. 2009, Hammerschlag et al. 2010a,b). Nearshore predators are also presumed to be more active during crepuscular and nocturnal periods, yet studies investigating diel patterns of nearshore predators are few and little empirical evidence exists in support of increased predator activity during dark periods. Chapter 1 therefore examined and compared the predatory fish assemblage within the mangrove and seagrass beds of Biscayne Bay over 24-hr periods along a distance and habitat gradient from the mangrove edge and nearshore environment (0–300 m) to farshore (301–700 m) seagrass beds.
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