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Factors Influencing Annual Survival and Recovery Rates, Primary Feather Molt, and Hatch Chronology of White-winged Doves in TexasHall, Jared Daniel 19 May 2018 (has links)
<p> Understanding survival and breeding season length of game birds are important for effective management and conservation. By determining the variables that drive survival and recovery rates for white-winged doves (<i>Zenaida asiatica</i>), I can offer management implications to agencies across their range. There is currently little knowledge about white-winged dove molting and hatching chronology. The objectives of this study were to: 1) investigate annual survival and recovery rates of white-winged doves, 2) determine intrinsic and extrinsic factors influencing them, 3) determine AHY primary feather molt rate and the factors that influence molt rate and initiation, and 4) describe hatch chronology and determine the factors that influence hatching. To understand what influences annual survival and recovery, I examined subpopulation, climate variables, urbanization characteristics, molt, and band type as covariates. I used the Brownie approach in the RMark package of R to compare annual survival and recovery models and generate estimates. I used Underhill and Zucchini models in the Moult package of R to determine AHY primary feather molt rate and the best predictors of molt rate and initiation. I analyzed molt scores of HY doves recorded during annual banding using GLMs in R to determine the factors that influence hatching. I used AIC to select the most parsimonious models for each <i>a priori</i> candidate set. I analyzed 71,675 bands, of which, 3,086 were recovered from 2007 – 2016. My most supported model influencing survival and recovery was [<i>S</i>(age class x urban intensity) <i>f</i>(age class X MRPP)]. Average AHY primary molt rate across Texas was 13.21 ± 0.93 days. MRPP subpopulation + Year was the most supported model influencing AHY primary molt rate, AHY molt initiation, and hatch date. Within my sample, 95% of AHY white-winged doves began molting from 7 April to 8 July and completed molt 17 August to 17 November. White-winged doves hatched as early as 6 January and as late as 27 July, with 95% of all hatching occurring between 22 March and 18 June and peaking at 5 May. Urban intensity was an important variable influencing annual survival, which is expected for such an urbanized species. MRPP subpopulations influenced vital rates and should be considered for future harvest management. </p><p>
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A Case Study Analysis of Collaborative Conservation| Restoring Bighorn Sheep to the Santa Catalina MountainsHawkins, Tricia Oshant 22 March 2018 (has links)
<p> Involving a diversity of stakeholders in conservation issues is an important and growing trend in wildlife management. My thesis provides a case study of a collaborative conservation effort in which representatives from sportsmen’s and environmental groups came together to advise the Arizona Game and Fish Department in a project to restore bighorn sheep to the Santa Catalina Mountains near Tucson, Arizona. These stakeholders formed the Catalina Bighorn Sheep Restoration Advisory Committee to help address the human dimension factors of the project, build public support, and guide project planning and implementation. In addition to participant observation and document analysis informing my study, I surveyed 31 stakeholders both on and off the Advisory Committee and interviewed key Advisory Committee members. All stakeholders were in favor of collaborative conservation. However, there were objections to this particular Advisory Committee for this particular project. Although stakeholders had a diversity of values that informed their beliefs, the Advisory Committee members who took the time to understand the science involved, develop mutual trust and respect for others at the table, and held a strong commitment to the project goals were able to shift deeply held, values-based beliefs and find consensus on contentious project elements. This included agreeing on a mountain lion management plan that called for the killing of mountain lions that preyed on the newly reintroduced bighorn sheep. Stakeholders not on the Advisory Committee did not come to agreement on most elements of the project. This study contributes to the understanding of collaborative conservation efforts by providing a case study of a controversial wildlife conservation project that involved diverse stakeholders who worked together, successfully found consensus, and achieved their main goal of getting bighorn sheep back on the mountain.</p><p>
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Animal Movement in a Changing WorldNu?ez, Tristan A. 27 April 2018 (has links)
<p> Animal movement influences ecological and biogeographical dynamics, and studying it reveals helpful insights at a time when anthropogenic activities have accelerated rates of climatic and land cover change. This dissertation addresses three fundamental questions in ecology and biogeography linked to the movement and distribution of animals. First, how do animal movements affect their environments? Second, how do the effects of land use change interact with atmospheric climate change to alter species distributions? Third, how do organisms track their climatic niches through time and space? Each question is addressed with a separate study, each generating methods and results with implications for future academic work, management, and conservation. </p><p> In the first study, I tracked the daily movements of the common hippopotamus, <i> Hippopotamus amphibius</i>, a megaherbivore that transports nutrient-rich biomass between terrestrial and aquatic ecosystems. I developed a spatially explicit biomass transfer model that relates rates of ingestion and egestion to movement behavior states derived from the movement data. The biomass transfer model revealed the process by which <i>H. amphibius</i> generates patterned landscapes of nutrient removal and deposition hotspots. In addition, the model generated maps of these nutrient transfer landscapes, making it possible to explore the spatial dynamics of nutrient transfers, and showing that the amount of biomass transferred reaches levels equivalent to rates of aboveground net primary productivity. In addition to revealing the influences of <i>H. amphibius</i> on ecosystem ecology, this study also provided metrics of home range size, habitat use, and movement behavior useful for conservation planning. </p><p> The first study provides a method for nutrient transfer mapping which could be applied to many other species, and leverages increasing quantities of high-resolution movement tracking data to map transfers of nutrients across landscapes. This can help predict the landscape-scale ecological changes resulting from the loss of animal movements that provide nutrient transfers. The approach can also be used to map other material transport dynamics, such as animal-transported seed dispersal or the movement of persistent organic pollutants. </p><p> In the second study, I used species distribution modeling to identify the interacting effects of climate and land use change on the distribution of <i>H. amphibius</i>. Hydrologic change is likely to result from ongoing shifts from rain-fed to irrigated agriculture across much of sub-Saharan Africa, where <i>H. amphibius</i> occurs. A lack of spatial data on hydrology, especially data temporally consistent with atmospheric climate datasets, has made it difficult to build species distribution models for semiaquatic species, such as <i>H. amphibius</i>, which are physiologically dependent on surface water. I overcame this challenge by coupling a simple hydrologic model to scenarios of land use and climate change, identifying potential effects on <i>H. amphibius</i> distributions. I found that increased levels of streamflow abstraction from irrigation will lead to much greater declines in <i>H. amphibius</i> habitat suitability than arise from scenarios of climate change alone. I also contrasted predictions of <i>H. amphibius</i> distributions that incorporated only atmospheric climate variables to predictions that also incorporated hydrologic variables, and found significant improvements in model performance when hydrology was incorporated. </p><p> The second study provides support for using predictive variables with strong mechanistic links to the physiology or ecology of the focal species when building species distribution models. The study also outlines a way to generate surfaces of key hydrologic variables from the climate surfaces commonly used for species distribution modeling. These surfaces have the potential to greatly improve forecasts generated by other semiaquatic species distribution models. From a conservation perspective, the second study highlights the potential for substantial losses of <i>H. amphibius</i> habitat across Africa as a result of increases in irrigation development. Other semiaquatic species in the region, as well as those dependent on the keystone ecological role of <i>H. amphibius</i> and its nutrient-transporting movements, may be similarly affected. </p><p> In the third study, I explored the role of movement in shaping species distributions in variable climates. Climatic variability at multiple time scales causes suitable climatic conditions to shift across geographic space. Recent scholarship has proposed that two species traits, the ability to colonize suitable locations, referred to as dispersal, and the ability to continue to occupy an area with unsuitable conditions, referred to as persistence, facilitate niche tracking, the process by which species follow suitable conditions moving through geographic space. By developing a model that simulates niche tracking through historically observed patterns of temporal and spatial variability, I quantified how different dispersal and persistence abilities affect niche tracking potential. I found that both dispersal and persistence facilitate niche tracking, and that small increases in persistence ability result in surprisingly large increases in niche tracking potential. </p><p> The third study makes two main contributions to ecological niche theory and distribution modeling. (Abstract shortened by ProQuest.) </p><p>
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Seasonal movement and activity patterns of the endangered geometric tortoise, psammobates geometricusVan Bloemestein, Ulric Patrick January 2005 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / Due to the critical status of Psammobates geometricus and the vulnerability of their habitat, there is a need to allocate areas for their protection. The aim of this study was to provide information on the space requirements and activity level of geometric tortoises to facilitate future conservation efforts. The thread-and-spool method was used to compare short-term movements, habitat utilisation, and activity patterns of male and female tortoises over 15 and 20 days respectively, in autumn and spring. Through radiotelemetry, the long-term movements of 10 male and 11 female tortoises were evaluated from April 2002 to April 2003. Locality data for the short-term and long-term studies were used to calculate the size of activity areas and home ranges as minimum convex polygons and fixed kernel estimates. Male and female geometric tortoises were active throughout the year, and maintained a high level of activity in autumn and in spring. However, females were more active than males were in spring. Females may require more resources, particularly food, in spring when they produce eggs. Although males and females travelled similar distances in autumn and in spring, males displaced further than females displaced in both seasons. The movement path for males was often linear, perhaps because this path may enhance their opportunities to encounter females. Geometric tortoise males were substantially smaller than females, which may explain why the distances that males moved and displaced in spring were negatively correlated to environmental temperature. In autumn, when temperatures were lower than in spring, the distance travelled by males was not correlated to temperature. However, in autumn female displacement showed a positive correlation with environmental temperature. Geometric tortoises showed large inter-individual variation in home range size, which may contribute to the fact that home range size did not differ among the three different habitat types: mature renosterveld, burned renosterveld and the old agricultural fields. Average home range size was 11.5 ha for 95% fixed kernel estimates, and 7.0 ha for minimum convex polygon estimates. Body size influenced the home range size of female geometric tortoises, but had no effect on the home range size of male tortoises. Females had larger home ranges than male tortoises had, possibly because females were larger, but reproductive requirements of females may have played a role. During the dry season, home range size increased when compared to the wet season. The larger home range during the dry season, which is associated with high temperatures, may be related to a reduction in resource availability. The fewer resources available, the greater the distance the tortoises would need to travel in order to acquire the necessary resources. The small home range in the wet season may indicate an abundance of resources, but it may also be that large pools of standing water restrict the movements of tortoises.
Understanding the spatial and habitat requirements of P. geometricus will help to assess the viability of populations in disturbed and highly fragmented areas, and contribute to the conservation efforts for this endangered species. / South Africa
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Wildlife conservation in Zambia and the Landsafe Customary CommonsManning, Ian Patrick Alexander 16 June 2011 (has links)
This dissertation both proposes and records the ongoing implementation of a ‘Landsafe’ integrated conservation and development model for the customary commons of Zambia. In Volume I, a geographical historical perspective of the country is presented which concentrates on wildlife conservation and rural people. The changes wrought successively on indigenous peoples by invading native Africans of the Bantu linguistic group, then in turn on them by Europeans in the form of Charter Companies and later by Imperial Protectorate rule, and finally, by self-rule, is explored. The country’s evolution from Western colonialism and embedded liberalism, to exploitative neoliberalism and the concurrent emergence of the traditional patrimonial system - one modernised by its meeting with European captalism, is the backdrop and basis for the construction of Landsafe and its current implementation in two chiefdoms. Volume II presents the Landsafe ICDP model. This is based on the formation of chiefdom statutory trusts, with trustees elected by villagers of the customary commons; and the signing of co-management agreements with government departments in respect of wildlife, Game Management Areas, and protected forest land, forests, fisheries and water. The local District Councils would be signatory to such agreements, and the chiefs and their headmen would vest selected customary land in these trusts. These vested lands are then protected, allowing for controlled exploitation by investors - such that they do not impinge unnecessarily on traditional rights or on the re-establishment of traditional guardians of nature. Land may not, under any circumstances, be alienated from customary control. A log frame programme analysis procedure is adopted and a suggested formalisation methodology and procedures for implementing Landsafe included. Finally, the socio-ecology of the first project area in the Luangwa Valley is detailed, followed by a description of the implementation of the Landsafe programme; including a critical analysis comparing Landsafe theory to practice. / Thesis (PhD)--University of Pretoria, 2011. / Centre for Wildlife Management / unrestricted
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The influence of genetic relatedness on sociality and demography of female African elephantsMunishi, Linus Kasian January 2011 (has links)
Many elephant populations across Africa were or are being devastated by poaching and habitat loss, making population and range size for the species important issues of conservation concern in elephant ranging areas, including Tarangire National Park (TNP). Poaching and/or overhunting are known to have direct effects on the demography of elephant populations. The current understanding of the indirect effects of poaching on the sociality and demography of elephant populations is relatively poor, both at the group and an individual level. In this thesis the importance of genetic relatedness (as influenced by poaching) on sociality and demography of the female elephants was studied, using a combination of genetic, observation of behaviour and two decades of demography data collected from the northern subpopulation of TNP. I investigated and characterized the relatedness categories within elephant groups. Using a conceptual model for group size analysis in aggregation economies, I hypothesized that elephant populations subject to social disruptions due to poaching would exhibit characteristics of the free entry model, whereas more stable, closed populations would better fit the group-controlled model. I present a rare quantitative analysis of genetic relatedness and group size patterns among groups of adult female elephants in two wild populations: one in Tarangire National Park (TNP), Tanzania, and another in Addo Elephant National Park (AENP), South Africa. I demonstrate that the group size in African elephant populations is governed by genetic relatedness, and that poaching/overhunting has a significant influence upon the apparent group formation and size in elephants. I then focused on the effect of relatedness on agonistic interactions between adult females. I hypothesized that individual-based aggressive interactions among adult female African elephants would vary according to degree of kinship, with closely related dyads showing less aggression towards each other in resource-limited environments, thereby leading to indirect fitness benefits for individuals. As predicted, females did not show agonistic interactions to their close kin most often, and the frequency and intensity of aggressive interactions was inversely related to the degree of relatedness of the interactants. The effect of group relatedness and structure on reproductive success of individual female African elephant in TNP was also investigated. Adult female reproductive success was significantly influenced by within- group relatedness and structure. Higher reproductive success (with higher frequency of calf production and survival and more female calves produced) were more evident in the closely related groups than groups with low relatedness, suggesting that females from genetically disrupted groups are less likely to be reproductive than those in closely related groups. The possibility of negative effects of poaching on the subsequent generation of poached adult females and the alternative of a positive demographic response through reduced density was assessed by analysing the demographic patterns of the first generation (F1) females of prime-aged adult female African elephants in TNP using within- group relatedness and size. I also compared vital rate (age of first birth and interbirth interval) responses of first generation (F1) cows from Tarangire (poached) elephants with other females from poached (Northern Luangwa National Park, Zambia) and unpoached (Amboseli National Park, Kenya and Addo Elephant National Park, South Africa) populations. Group relatedness had no significant effect on sex ratio of the F1 cows‟ calves. There was a significant difference between the mean age of first birth and interbirth interval of F1 cows from the two (poached, Tarangire and unpoached, Amboseli National Park) elephant populations, suggesting that elephant populations reduced by poaching to low levels show an increase vigour through release from density constraints. Based on these results, the broader implications of secondary effects of poaching on elephant populations are critically evaluated. Also the importance of understanding the consequences of these effects is highlighted in light of other elephant conservation and management approaches. This understanding is useful in making conservation and management decisions for elephants and other biodiversity.
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Wildlife response to habitat fragmentation and other human influences in tropical montane evergreen forests, northern ThailandPattanavibool, Anak 08 January 2018 (has links)
Montane evergreen forests in northern Thailand have been severely fragmented and converted to agricultural lands and other forms of development that affect wildlife. The objectives of this study were to examine patterns and changes in montane evergreen forest patches, and document wildlife responses in terms of species diversity, abundance, and distribution. The study was conducted in Om Koi and Mae Tuen Wildlife Sanctuaries, Chiang Mai and Tak Provinces. LANDSAT TM imagery, aerial photographs, GIS, and the spatial pattern analysis program FRAGSTATS were employed to examine landscape patterns and changes. I found that Om Koi still maintained large patches (>400ha) with connectivity while Mae Tuen was comprised mainly of small isolated patches (<100 ha). Mae Tuen lost 2,640 ha of montane evergreen forest within 50 years compared to 888 ha in Om Koi. Road development and cabbage cultivation in Mae Tuen played a major role in accelerating forest loss. For the wildlife survey, I compared 4 forest patches in Mae Tuen, which are heavily fragmented and disturbed, with another 4 in Om Koi, where human influences are less. I used 1-km transects to survey animals in each patch. For mammals, 156 5 x 1m track recording stations were set up in each location for recording footprints. Over a 9-month period from September 1997 to June 1998 I found 9 species of mammals in Mae Tuen and 19 in Om Koi. I also found 89 species (1,238 detections) of birds in Mae Tuen and 119 (1,192) in Om Koi. Large patches (>400 ha) with connectivity still supported large mammals, primates, and a high diversity of birds. Bird diversities were significantly greater (P = 0.011) in large patches in Om Koi than in the small patches in Mae Tuen. Large frugivorous birds such as hornbills were found in Om Koi but there were none in Mae Tuen. Small patches (<100 ha) in Mae Tuen were still valuable for forest birds and virtually no penetration by clearing birds was found. Track counts gave 886 mammal tracks in Mae Tuen and 2,016 in Om Koi. Om Koi patches still support large mammals such as the Asian elephant (Elephas maximus), tiger (Panthera tigris), Asiatic black bear (Selenarctos thibetanus), and sambar (Cervus unicolor) but there were none in Mae Tuen. Three species of primates existed in Om Koi but they were virtually extinct from Mae Tuen. There were traces of a positive relationship between bird and mammal diversities and patch size. The distribution model for elephants suggests that villages in the middle of elephant seasonal migratory paths must be restricted from development and slash-and-burn cultivation to reduce the impact on elephant populations. The small population of bantengs (Bos javanicus) was confined to a small area as revealed by the distribution model. These animals need urgent and effective protection to avoid extirpation. Hunting, burning, and domestic cattle dispersing into the forest are other influences threatening wildlife in the areas. / Graduate
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Analysis of mountain lion predation upon mule deer and elk in the Idaho Primitive areaHornocker, Maurice Gail January 1967 (has links)
This study was designed (1) to investigate the dynamics of a mountain lion population, and (2) to assess the impact of a population of lions on populations of big-game animals. The research was carried on in the Idaho Primitive area; intensive work was limited to the winter and early spring seasons.
Lion population numbers were stable during the three-year study period, and available evidence indicates the present population
level existed for some time prior to the start of the study-Intraspecific relationships, manifested through territoriality, acted to limit lion numbers and maintain population stability. Dispersal and mortality, particularly of young individuals, appeared to be important limiting mechanisms.
The population was centered around a nucleus of mature individuals well-established on territories, but segments of the population were dynamic, exhibiting an inflow and outflow of individuals from season to season. These transients were composed predominantly of young animals.
Strife appeared to be kept to a minimum by a "mutual avoidance" behavorial mechanism. Specific hunting territories were shared but appeared never to be used by more than one lion or family of lions at a time. Individuals, regardless of sex, appeared to respect the presence of another in a specific area. The "mutual avoidance" hypothesis is advanced as an important factor in the maintenance of lion populations. This mechanism provides for the distribution of lions in both space and time without costly-fighting. It also appears to insure greater success in securing large prey animals.
Population size of prey species -- mule deer, elk, and bighorn
sheep -- was established by making ground and aerial counts each year. Bighorn sheep numbers remained constant during the three-year period, but populations of deer and elk, the principal prey species, increased. The range was considered overstocked by deer and elk.
Forty-four elk and 39 deer were recorded as definitely killed by lions during the three-year period. Only two kills of bighorn sheep were found; lion predation on this species appeared insignificant.
Seventy-five percent of the elk killed by lions were 1% years old or less and 9% years or older; 57 percent of the deer kills were in these age classes. More "young" than "old" animals were killed. Lions were non-selective in their killing, except for "negative selectivity" in the case of mature bull elk. Factors acting separately or collectively to increase prey vulnerability included prey density, behavior, age, health, inter - and perhaps intraspecific strife, and the lion's predatory characteristics.
It was concluded that elk and deer populations were limited by the winter food supply and that predation by lions was inconsequential
in determining ultimate numbers of elk and deer. Lion predation, however, is a powerful force acting to dampen and protract severe prey oscillations and to distribute ungulates on restricted, critical range. From the theoretical standpoint, it also appears to be a strong evolutionary force, acting to remove less fit individuals from the population. The effects and influence of such predation are considered of great significance in the maintenance of ecologic stability in wilderness environments. / Science, Faculty of / Zoology, Department of / Graduate
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The human factor in mouse lemur (Microcebus griseorufus) conservation: Local resource utilization and habitat disturbance at Beza Mahafaly, SW MadagascarRasoazanabary, Emilienne 01 January 2011 (has links)
Gray-brown mouse lemurs (Microcebus griseorufus) are able to survive in the most stressful environments of Madagascar. Between 2003 and 2007, I collected data on threats to the survival of M. griseorufus at Beza Mahafaly and how various factors impact their behavior. Individuals can survive ∼5 years, but few do. Females give birth to multiple young in single litters; furthermore, polyestry exists at Beza. Population turnover rates are higher than they are for other mouse lemurs, which also live longer. The morphology and behavior of M. griseorufus in three populations (protected gallery and spiny forests; unprotected forest at Ihazoara) at Beza are influenced by differences in vegetation. Gallery-forest mouse lemurs have hook-like hands and feet while those in the spiny forest have more “clamp-like” cheiridia. Differences in feeding and nesting behavior may explain these differences, as mouse lemurs in the different habitats use small branches in high canopy vs. larger supports close to the ground to different degrees. Morphology and behavior also vary by sex. Reverse sexual canine dimorphism is strong in M. griseorufus at all three forests. The greater canine height of females likely relates to female dominance. Females have greater access to exudate-producing trees and to tree-holes for nesting. They undergo seasonal torpor more frequently than males, and this may give them a survival advantage. Mouse lemurs are not hunted for food but their habitats are disturbed. In the most highly-disturbed (unprotected) forest, I recorded the highest population turnover rate and shortest maximum lifespan. Ihazoara mouse lemurs here cannot fatten or hibernate. But even in “protected” forests where they do hibernate, mouse lemurs suffer from the felling of trees and herding of cattle. The Mahafaly people are cattle herders and faithful to their culture. The externally-imposed prohibition against resource extraction in protected forests engenders local hostility toward conservation. Education has minimally affected these attitudes. Building a more healthy relationship between conservationists and local people is of paramount importance; the views of local people must be considered and more of an effort made to involve local communities in constructing effective conservation strategies.
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Flagship species, tourism, and support for Rubondo Island National Park, TanzaniaStevens, Sadie S 01 January 2011 (has links)
Two major goals of managers of Rubondo Island National Park (Rubondo), Tanzania are to increase the number of international visitors to the Park (and thereby increase revenue generated) and to increase support for the Park among residents of nearby communities. I investigated species preferences among children living around Rubondo and the wildlife viewing preferences of international visitors to Tanzania in an attempt to identify flagship species that Park management could use in marketing and outreach campaigns designed to meet their goals. I also assessed local interest in visiting the Park. As local flagships for Rubondo, the Egyptian goose (Alopochen aegyptiacus ) and silver cyprinid (Rastrineobola argentea) appear to have the most potential among the species that I assessed (i.e., fish eagle [Haliaeetus vocifer], Egyptian goose, silver cyprinid, little egret [Egretta garzetta], sitatunga [Tragelaphus speki], genet [Genetta tigrina], monitor lizard [Varanus niloticus], spotted-necked otter [Lutra maculicollis], vervet monkey [Cercopithecus pygerythrus], crocodile [Crocodylus niloticus], hippopotamus [ Hippopotamus amphibius], giraffe [Giraffa camelopardalis ], and elephant [Loxodanta africana]). However, based on either range or limited aesthetic/behavioral appeal, I considered neither species useful as an international flagship. Among species on Rubondo included in investigations of potential international flagships for the Island (including the chimpanzee [Pan troglodytes], crocodile, elephant, giraffe, hippopotamus, vervet monkey, bushbuck, fish eagle, large-spotted genet, goliath heron [Ardea goliath], monitor lizard, sitatunga, and spotted-necked otter), few were concluded to have potential, either because participating visitors had limited "awareness" of and "interest" in viewing the species, local people had strong negative opinions of the species, the animals are not native to the Island, and/or the animals are more easily viewed in more readily-accessible locations. Local people generally had not visited Rubondo but wanted to visit. Not having visited the Park appeared to influence perceptions of the Park, wildlife tourism, and conservation among some participants. Recommendations for local and international marketing and outreach strategies for Rubondo are made based on the outcomes of the aforementioned investigations of local and international species preferences and interest in visiting the Park.
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