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The Rhino Bond is the first financial instrument dedicated to protecting a species. The Bond allows investors to invest in the conservation of the black rhinoceros Diceros bicornis, with the amount of money returned by the investment depending on whether rhinoceros numbers increase (and by how much). In this paper we focus on how the Bond was brought into being. We draw on an analysis of organizational reports along with data collected from interviews with key informants to investigate the roles of the various stakeholders in the Bond, how species and sites were selected, the motivations and experiences of the stakeholders and the involvement of stakeholders in decision-making. We found that although conservation actors are attracted by the potential for new funding, they have experienced challenges navigating complex financial instruments. The needs of financial actors often dictated decision-making, with implications for the species and sites chosen for the Bond. As profits are tied to an increase in population size of a specific species (which needs to be monitored), the instrument has favoured large and easily counted species and populations. Only some sites were able to meet the stringent conditions of financial instruments, including metrics on financial sustainability. We argue that the dominance of financial principles and motives means that not all species or sites will be viable candidates for investment and that conservation finance should not be seen as a panacea.

The Rhino Bond is the first financial instrument dedicated to protecting a species. The Bond allows investors to invest in the conservation of the black rhinoceros Diceros bicornis , with the amount of money returned by the investment depending on whether rhinoceros numbers increase (and by how much). In this paper we focus on how the Bond was brought into being. We draw on an analysis of organizational reports along with data collected from interviews with key informants to investigate the roles of the various stakeholders in the Bond, how species and sites were selected, the motivations and experiences of the stakeholders and the involvement of stakeholders in decision-making. We found that although conservation actors are attracted by the potential for new funding, they have experienced challenges navigating complex financial instruments. The needs of financial actors often dictated decision-making, with implications for the species and sites chosen for the Bond. As profits are tied to an increase in population size of a specific species (which needs to be monitored), the instrument has favoured large and easily counted species and populations. Only some sites were able to meet the stringent conditions of financial instruments, including metrics on financial sustainability. We argue that the dominance of financial principles and motives means that not all species or sites will be viable candidates for investment and that conservation finance should not be seen as a panacea. [ABSTRACT FROM AUTHOR]

Estimating the population parameters, performance and factors that influence reproduction from long-term, individual-based monitoring data is the gold standard for effective wildlife management and conservation. Yet this information is often difficult and costly to collect or inaccessible to managers. We synthesized a 20-year set of individual-based monitoring data from a subset of black rhinoceros Diceros bicornis subpopulations across a range of environmental conditions in Namibia. Our findings demonstrate that despite the relatively arid landscape in Namibia, the black rhinoceros metapopulation is performing well, measured by age at first reproduction, inter-birth interval, population growth and survivorship. Information-theoretic modelling revealed that a univariate model including normalized differential vegetative index had a greater influence upon age at first reproduction than population density. The inter-birth interval model set identified cumulative rainfall during the 15 months prior to the birth month as the top model, although the mean normalized differential vegetative index during the inter-birth interval was comparable. There was little evidence for density-dependence effects on reproduction. These findings suggest that although browse quality could have a greater impact on parameters spanning multiple years, shorter-term parameters could be more influenced by rainfall. Our analysis also revealed a synchronous pattern of conceptions occurring in the rainy season. Our study provides a set of population parameter estimates for Namibian black rhinoceros subpopulations and preliminary insights on factors driving their reproduction. These expand our collective knowledge of global black rhinoceros population dynamics and improve our confidence and capability to adaptively manage the black rhinoceros metapopulation of Namibia.

Estimating the population parameters, performance and factors that influence reproduction from long-term, individual-based monitoring data is the gold standard for effective wildlife management and conservation. Yet this information is often difficult and costly to collect or inaccessible to managers. We synthesized a 20-year set of individual-based monitoring data from a subset of black rhinoceros Diceros bicornis subpopulations across a range of environmental conditions in Namibia. Our findings demonstrate that despite the relatively arid landscape in Namibia, the black rhinoceros metapopulation is performing well, measured by age at first reproduction, inter-birth interval, population growth and survivorship. Information-theoretic modelling revealed that a univariate model including normalized differential vegetative index had a greater influence upon age at first reproduction than population density. The inter-birth interval model set identified cumulative rainfall during the 15 months prior to the birth month as the top model, although the mean normalized differential vegetative index during the inter-birth interval was comparable. There was little evidence for density-dependence effects on reproduction. These findings suggest that although browse quality could have a greater impact on parameters spanning multiple years, shorter-term parameters could be more influenced by rainfall. Our analysis also revealed a synchronous pattern of conceptions occurring in the rainy season. Our study provides a set of population parameter estimates for Namibian black rhinoceros subpopulations and preliminary insights on factors driving their reproduction. These expand our collective knowledge of global black rhinoceros population dynamics and improve our confidence and capability to adaptively manage the black rhinoceros metapopulation of Namibia. [ABSTRACT FROM AUTHOR]

Variations in forage availability, selection and preferences can lead to intense foraging competition and depletion of food consequently lowering diet quality and population performance of black rhino species. This study investigated seasonal variations in rhino diet, foraging, preference and browsing intensity and how this is influenced by plant diversity and availability in Mkomazi National Park (MKONAPA). Fifty‐eight square grids were randomly selected in each season, and plots were laid for vegetation assessment during wet and dry seasons in the sanctuary. Browsed species by rhinos were compared with rhino feeding data from fourteen rhino range areas within Africa. More than 85% of species edible in MKONAPA were similar to those in rhino range areas. Acalypha ornata, Grewia similis and Commiphora africana were highly utilised specie in both seasons. Diversity and abundance of consumed browses decreased towards the dry season while browsing intensity increased with forage preference in both seasons and was prominent when browse availability was low in dry seasons. Our study established seasonal variation in dietary composition, browsing intensity and preferences for black rhinos. We suggest establishing nutritional composition of preferred forages, assessing density of competitor browsers, translocating excess rhinos or expanding the sanctuary to meet the recommended ecological carrying capacity. [ABSTRACT FROM AUTHOR]

BackgroundUnderstanding rhino movement behavior, especially their recursive movements, holds significant promise for enhancing rhino conservation efforts, and protecting their habitats and the biodiversity they support. Here we investigate the daily, biweekly, and seasonal recursion behavior of rhinos, to aid conservation applications and increase our foundational knowledge about these important ecosystem engineers.MethodsUsing relocation data from 59 rhinos across northern Namibia and 8 years of sampling efforts, we investigated patterns in 24-h displacement at dawn, dusk, midday, and midnight to examine movement behaviors at an intermediate scale and across daily behavioral modes of foraging and resting. To understand recursion patterns across animals' short and long-term ranges, we built T-LoCoH time use grids to estimate recursive movement by each individual. Comparing these grids to contemporaneous MODIS imagery, we investigated productivity's influence on short-term space use and recursion. Finally, we investigated patterns of recursion within a year's home range, measuring the time to return to the most intensively used patches.ResultsTwenty four-hour displacements at dawn were frequently smaller than 24-h displacements at dusk or at midday and midnight resting periods. Recursion analyses demonstrated that short-term recursion was most common in areas of median rather than maximum NDVI values. Investigated across a full year, recursion analysis showed rhinos most frequently returned to areas within 8-21 days, though visits were also seen separated by months likely suggesting seasonality in range use.ConclusionsOur results indicate that rhinos may frequently stay within the same area of their home ranges for days at a time, and possibly return to the same general area days in a row especially during morning foraging bouts. Recursion across larger time scales is also evident, and likely a contributing mechanism for maintaining open landscapes and browsing lawns of the savanna.

Globally, wildlife populations are becoming increasingly small and isolated. Both processes contribute to an elevated risk of extinction, notably due to genetic factors related to inbreeding depression and a loss of adaptive potential. Wildlife translocation is a valuable conservation tool to reintroduce species to previously occupied areas, or augment existing populations with genetically divergent animals, thereby improving the viability of endangered populations. However, understanding the genetic implications of mixing gene pools is key to avoid the risk of outbreeding depression, and to maximise translocation effectiveness. In this study we used mitochondrial and microsatellite DNA collected from 110 black rhinoceroses (Diceros bicornis minor) in Kruger National Park, South Africa, to determine levels of genetic diversity, inbreeding and relatedness. We compared this diversity with the two source populations (KwaZulu-Natal, South Africa and Zambezi River, Zimbabwe) using data from previously published studies, and assessed changes in the relative contribution of source lineages since their reintroduction in the 1970s. Our results show that Kruger's black rhinoceroses are genetically more diverse than those from KwaZulu-Natal, with levels closer to those from the Zambezi Valley. Furthermore, our findings indicate a relative increase in the Zimbabwean lineage since reintroduction, suggesting a possible selective advantage. From a conservation perspective, our results demonstrate the benefits of mixing multiple source populations to restore gene flow, improve genetic diversity and thereby help protect small, isolated populations from extinction. [ABSTRACT FROM AUTHOR]

BACKGROUND: Understanding rhino movement behavior, especially their recursive movements, holds significant promise for enhancing rhino conservation efforts, and protecting their habitats and the biodiversity they support. Here we investigate the daily, biweekly, and seasonal recursion behavior of rhinos, to aid conservation applications and increase our foundational knowledge about these important ecosystem engineers. METHODS: Using relocation data from 59 rhinos across northern Namibia and 8 years of sampling efforts, we investigated patterns in 24-h displacement at dawn, dusk, midday, and midnight to examine movement behaviors at an intermediate scale and across daily behavioral modes of foraging and resting. To understand recursion patterns across animals short and long-term ranges, we built T-LoCoH time use grids to estimate recursive movement by each individual. Comparing these grids to contemporaneous MODIS imagery, we investigated productivitys influence on short-term space use and recursion. Finally, we investigated patterns of recursion within a years home range, measuring the time to return to the most intensively used patches. RESULTS: Twenty four-hour displacements at dawn were frequently smaller than 24-h displacements at dusk or at midday and midnight resting periods. Recursion analyses demonstrated that short-term recursion was most common in areas of median rather than maximum NDVI values. Investigated across a full year, recursion analysis showed rhinos most frequently returned to areas within 8-21 days, though visits were also seen separated by months likely suggesting seasonality in range use. CONCLUSIONS: Our results indicate that rhinos may frequently stay within the same area of their home ranges for days at a time, and possibly return to the same general area days in a row especially during morning foraging bouts. Recursion across larger time scales is also evident, and likely a contributing mechanism for maintaining open landscapes and browsing lawns of the savanna.

Abstract Background Understanding rhino movement behavior, especially their recursive movements, holds significant promise for enhancing rhino conservation efforts, and protecting their habitats and the biodiversity they support. Here we investigate the daily, biweekly, and seasonal recursion behavior of rhinos, to aid conservation applications and increase our foundational knowledge about these important ecosystem engineers. Methods Using relocation data from 59 rhinos across northern Namibia and 8 years of sampling efforts, we investigated patterns in 24-h displacement at dawn, dusk, midday, and midnight to examine movement behaviors at an intermediate scale and across daily behavioral modes of foraging and resting. To understand recursion patterns across animals’ short and long-term ranges, we built T-LoCoH time use grids to estimate recursive movement by each individual. Comparing these grids to contemporaneous MODIS imagery, we investigated productivity’s influence on short-term space use and recursion. Finally, we investigated patterns of recursion within a year’s home range, measuring the time to return to the most intensively used patches. Results Twenty four-hour displacements at dawn were frequently smaller than 24-h displacements at dusk or at midday and midnight resting periods. Recursion analyses demonstrated that short-term recursion was most common in areas of median rather than maximum NDVI values. Investigated across a full year, recursion analysis showed rhinos most frequently returned to areas within 8–21 days, though visits were also seen separated by months likely suggesting seasonality in range use. Conclusions Our results indicate that rhinos may frequently stay within the same area of their home ranges for days at a time, and possibly return to the same general area days in a row especially during morning foraging bouts. Recursion across larger time scales is also evident, and likely a contributing mechanism for maintaining open landscapes and browsing lawns of the savanna.

Poaching on private land may potentially significantly deplete the rhino population yet is poorly studied. We focus on temporal patterns in poaching events, whether there is any evidence of targeting of specific categories of rhino (in relation to species, sex and age) and whether these patterns in poaching show any trends over time. Using rhino owner and (mainstream and social) media reports, we complied a database of private land poaching events between 2003 and 2017. Patterns in poaching activity were broadly consistent over time. Poaching is most likely at night, under the full moon, and close to the property perimeter. Whilst there was no consistent temporal pattern in poaching, there was evidence of increased poaching during the weekend (Friday–Sunday) compared to weekdays (Monday–Thursday) in 2017. Prioritising rhino protection efforts at these times may therefore be the most efficient use of limited resources. Because there is no evidence that poachers selectively target rhinos, efforts undertaken by private owners to protect specific individuals or groups may be ineffective. Our research also highlighted key data that were currently not clearly recorded, including collateral calf deaths and lost pregnancies, which may have a significant impact on the scale of the rhino poaching problem. [ABSTRACT FROM AUTHOR]

In contrast to understanding spinescence in savanna woody species, little is known about the functions of plant secondary metabolites (PSM). Negative effects of PSMs on individual animal performance potentially translate into negative effects on herbivore population growth. Hence, understanding PSM functions is important for the conservation of savanna megafauna. We tested the view that black rhinoceros (Diceros bicornis) diet preference is not affected by spinescence or total phenolic abundance. We hypothesized that the composition of phenolic mixtures, however, would affect preference. Furthermore, we tested our data from 71 woody species for a trade-off between structural and chemical defenses. Spinescence type, and spinescence generally, did not deter black rhino feeding. Using eco-metabolomic data, we found that total abundance of phenolics did not affect preference, but mixture composition did and that the probability of spinescence trading off against phenolics depended on the mixture. We note that our study was restricted to black rhino and that diet preferences of other mammal herbivores might be influenced by subtle differences in phenolic mixtures. However, our results did support a previous, more detailed study of phenolic profiles of six species showing the same patterns in relation to preference generalised across mammal herbivore species in savannas. Our results represent substantial advancement in the understanding of the roles of PSMs, especially flavonoid compounds, in the functioning of savanna ecosystems, and highlight the need to dig deeper into broad groups of traits such as spinescence or total phenolics to improve understanding of woody plant defenses in savannas. [ABSTRACT FROM AUTHOR]

Wildlife-based tourism poses opportunities and challenges for species conservation. Minimizing potential negative impacts of tourism is critical to ensure business and conservation enterprises can coexist. In north-western Namibia tourism is used as a conservation tool for the Critically Endangered black rhinoceros Diceros bicornis. However, black rhinoceroses are susceptible to human disturbance and may become displaced by tourist activities, which threatens not only the security and health of the rhinoceros population but also the sustainability of the business. We examined areas avoided by black rhinoceroses to understand how they respond to the type and extent of tourism development, and to evaluate management alternatives. We used spatial data on use of water sources by rhinoceroses to create a series of a priori candidate models that described the negative influences of tourist activities on rhinoceros habitat use. A model selection approach strongly supported a cumulative zones of influence model comprised of a 6 km buffer around the airstrip combined with a 1 km buffer around roads used daily. We compared alternative management scenarios using the best-performing model and found that an optimal road-use policy combined with airstrip relocation could minimize the total area avoided by the black rhinoceros to 7.1% and loss of high quality habitat to 20.7%. Under the worst-case scenario the area avoided and loss of high quality habitat were 153 and 85% greater, respectively, than under the scenario with optimal management. Our findings provide a novel framework and a practical, policy-relevant decision support tool to improve the contribution of tourism to wildlife conservation. [ABSTRACT FROM AUTHOR]

Objectives: The black rhinoceros (Diceros bicornis) is an endangered mammal for which a captive breeding program is part of the conservation effort. Black rhinos in zoo's often suffer from chronic infections and heamochromatosis. Furthermore, breeding is hampered by low male fertility. To aid a research project studying these topics, we sequenced and assembled the genome of a captive male black rhino using ONT sequencing data only., Data Description: This work produced over 100 Gb whole genome sequencing reads from whole blood. These were assembled into a 2.47 Gb draft genome consisting of 834 contigs with an N50 of 29.53 Mb. The genome annotation was lifted over from an available genome annotation for black rhino, which resulted in the retrieval of over 99% of gene features. This new genome assembly will be a valuable resource in for conservation genetic research in this species., (© 2024. The Author(s).)

Abstract The successful conservation plans of megaherbivores necessitate precisely characterizing their ecological needs in order to optimize reproduction rates and reintroduction plans. The black rhino (Diceros bicornis L.) is among the most endangered species of megaherbivores in Africa and its conservation relies on nature reserves that are bound and habitat‐restricted. Therefore, identifying the optimal amount of space this species needs and the factors driving its habitat use are crucial for establishing reserve priority plans. Knowing that forage selection is an important component linked to herbivore spatial distribution, we combined 5 years of sightings data with observations of rhinos' vegetation type and forage preferences to address their forage selection across multiple spatial scales. We found that black rhinos' spatial distribution was negatively associated with ecosystem productivity, but positively associated with specific vegetation types that contain highly preferred, chemically distinct, plant species. Black rhinos thus occupy their habitat across space and time through selective foraging on preferred plants.

The successful conservation plans of megaherbivores necessitate precisely characterizing their ecological needs in order to optimize reproduction rates and reintroduction plans. The black rhino (Diceros bicornis L.) is among the most endangered species of megaherbivores in Africa and its conservation relies on nature reserves that are bound and habitat‐restricted. Therefore, identifying the optimal amount of space this species needs and the factors driving its habitat use are crucial for establishing reserve priority plans. Knowing that forage selection is an important component linked to herbivore spatial distribution, we combined 5 years of sightings data with observations of rhinos' vegetation type and forage preferences to address their forage selection across multiple spatial scales. We found that black rhinos' spatial distribution was negatively associated with ecosystem productivity, but positively associated with specific vegetation types that contain highly preferred, chemically distinct, plant species. Black rhinos thus occupy their habitat across space and time through selective foraging on preferred plants. [ABSTRACT FROM AUTHOR]

The conservation of threatened species requires information on how management activities influence habitat quality. The Critically Endangered black rhinoceros Diceros bicornis is restricted to savannahs representing c. 5% of its historical range. Fire is used extensively in savannahs but little is known about how rhinos respond to burning. Our aim was to understand rhino responses to fire by studying habitat selection and foraging at multiple scales. We used resource selection functions and locations of 31 rhinos during 2014–2016 to study rhino habitat use in Serengeti National Park, Tanzania. Rhino selectivity was quantified by comparing forage consumption to plant species availability in randomly sampled vegetation plots; rhino diets were subsequently verified through DNA metabarcoding analysis of faecal samples. Rhino habitat use was a unimodal function of fire history, with highly occupied sites having fire frequencies of < 0.6 fires/year and maximum occupancy occurring at a fire frequency of 0.1 fires/year. Foraging stations had characteristic plant communities, with 17 species associated with rhino foraging. Rhinos were associated with, and disproportionately consumed, woody plants, forbs and legumes, all of which decreased in abundance with increasing fire frequency. In contrast to common management practices, multiple lines of evidence suggest that the current fire regime in the Serengeti negatively influences rhino habitat use and foraging and that frequent fire limits access of rhinos to preferred forage. We outline a conceptual model to guide managers and conservationists in the use of fire under variable habitat conditions. [ABSTRACT FROM AUTHOR]

Rhinoceros poaching has been recognized the world over as a conservation crisis, the result of the high price of horn and demand in Asian markets. The commitment and participation of local people in conservation activities, however, are crucial for conservation success. Here we assess attitudes and perceptions towards rhino poaching and conservation in light of surveys in two local communities adjacent to the Hlane Royal National Park in eSwatini where perhaps 100 black ( Diceros bicornis) and white ( Ceratotherium simum) rhino occur. Our survey of 60 households addressed perceptions and attitudes towards rhino conservation and willingness to participate in rhino poaching and conservation activities. No efforts have been made to involve local people in conservation activities, and the people do not benefit from the park's activities. About 20% of respondents expressed their willingness to help rhino poachers provided they are paid for their services. Of the remaining 80%, some mentioned that they would not help poachers for fear of being apprehended. Still, some mentioned that they would not help poachers because of their concern about poaching and believe its prevention is important. Park authorities here and elsewhere could invest in building better people--park relationships, and provide opportunities for local communities to participate in conservation activities. Conservation policies to co-manage the resources could be used to deter poaching and to conserve wildlife involving local community members in monitoring and enforcement strategies. [ABSTRACT FROM AUTHOR]

'Eliska,' an endangered black rhino (Diceros bicornis), died suddenly in Mkomazi National Park in Tanzania in 2016. Three Amblyomma gemma ticks were collected from Eliska's body, and four ticks were collected from the surrounding field. We conducted 16S rRNA targeted high-throughput sequencing to evaluate the overall composition of bacteria in the ticks' microbiomes and investigate whether the ticks could be the cause of Eliska's death. The ticks collected from Eliska's body and the field were found to differ in their bacterial composition. Bacillus chungangensis and B. pumilus were the most commonly found bacteria in the ticks collected from the field, and B. cereus and Lysinibacillus sphaericus were the most commonly found in the ticks collected from Eliska's body. The abundance was higher in the ticks collected from the field. In contrast, the equity was higher in the ticks collected from Eliska's body. No known pathogenic bacteria that could explain Eliska's sudden death were found in any of the ticks. The differences between the microbiome of ticks collected from Eliska's body and from the field indicate that the microbiome of ticks' changes through the consumption of blood. Image 1 • Ticks were collected from a dead Black rhino of the endangered species Diceros bicorn. • Ticks collected from the body and the surrounding field had different microbiome patterns. • Bacillus chungangensis and B. pumilus were commonly found in the ticks collected from the field, and B. cereus and Lysinibacillus sphaericus were commonly found in the ticks collected from Black rhino. [ABSTRACT FROM AUTHOR]

Tourism may benefit conservation, but some wildlife viewing practices threaten the sustainability of both business and conservation initiatives. In north‐west Namibia, conservation‐oriented tourism provides tourists with an opportunity to encounter the critically‐endangered black rhinoceros Diceros bicornis on foot. We used 123 tourist‐rhinoceros encounters and employed a statistical modeling approach to: (1) identify the characteristics of human‐rhinoceros encounters that caused rhinoceros disturbance and displacement; and (2) design rhinoceros‐human encounter guidelines that improve sustainability. A model‐averaging, information‐theoretic approach identified tourist approach distance, viewing time and individual encounter exposure as the most significant predictors of rhinoceros disturbance level. A suite of rhinoceros viewing scenarios were modeled for acceptable disturbance risks, and adopted as a rhinoceros viewing policy. The policy reduced encounter displacements by 80% while maintaining a 95% positive feedback rating from guests. We demonstrate an evidence‐based, policy‐oriented management approach can help improve tourism's contribution towards the conservation of an endangered species. Tourism may benefit conservation but some wildlife viewing practices threaten the sustainability of both business and conservation initiatives. Using a case from rhinoceros tracking tourism in north‐west Namibia, we employed a statistical modeling approach to: (1) identify the characteristics of human‐rhinoceros encounters that caused rhinoceros disturbance and displacement; and (2) design rhinoceros‐human encounter guidelines that improve sustainability. The subsequent evidence‐based rhinoceros viewing policy reduced encounter displacements by 80% while maintaining a 95% positive feedback rating from guests. We demonstrate an evidence‐based, policy‐oriented management approach can help improve tourism's contribution towards the conservation of an endangered species. [ABSTRACT FROM AUTHOR]

This report describes weekly repeated anesthesia in a 7-yr-old, 1,030 kg, female Eastern black rhinoceros (Diceros bicornis michaeli), that was immobilized six times using a combination of 2 mg etorphine (0.002 mg/kg), 5 mg medetomidine (0.005 mg/kg), 25 mg midazolam (0.024 mg/kg), and 300 mg ketamine (0.29 mg/kg) delivered intramuscularly (IM) via remote dart to facilitate long-term medical care of a bilateral, obstructive Actinomyces sp. rhinitis. The drug combination described in this study resulted in reliable, rapid recumbency of the animal within 2–8 min after initial administration via dart and produced deep anesthesia for 34–78 min without supplemental anesthetic administration. Antagonist drugs (100 mg naltrexone [0.1 mg/kg] and 25 mg atipamezole [0.024 mg/kg] IM) produced reliable and uneventful recoveries in all the procedures. During each anesthetic procedure, the animal was intubated and provided intermittent positive pressure ventilation with a megavertebrate demand ventilator. Tachycardia and hypoxia noted after induction resolved after positive pressure ventilation with oxygen. This report provides useful information on a novel anesthetic protocol used repeatedly for intensive medical management in a black rhinoceros. [ABSTRACT FROM AUTHOR]

The study of endobiotic ciliates from the intestines of various zoo mammals is important for revealing the influence of various factors on endobiont communities. In this paper we describe the species diversity of endobiotic ciliates from the faeces of the eastern black rhinoceros Diceros bicornis michaeli (male and two females, mother and daughter) kept in the zoo. Seven species of the ciliates were found, among them Rhinozeta rhinozeta , R. triciliata and Prototapirella clypeata were observed in the rhinos only. The other two, Monoposthium sp. and Triplumaria sp., according to their morphology should have been identified as new ciliate species. Successful transmission of the endobionts from parents to the young rhino in the zoo was demonstrated. R. rhinozeta was investigated with the using of the methods of the light and immunofluorescence microscopy and molecular phylogeny. The composition and phylogeny of the family Cycloposthiidae were discussed. [ABSTRACT FROM AUTHOR]

Abstract: Small populations are vulnerable to founder effects, stochastic demographic events and inbreeding depression. These factors raise the extinction probability of small populations, and thus effective management plans for endangered species have become essential. The black rhinoceros (Diceros bicornis) survived a historic global population crash and is currently facing renewed threat through poaching, population fragmentation and isolation. South Africa is home to approximately 36% of the world's remaining black rhinos; however, this population is fragmented across parks and reserves, and many of these small populations remain geographically and genetically isolated. The historic population crash, subsequent fragmentation and relentless poaching pressure together threaten the viability of the black rhino population within South Africa. This study employed a practical, non‐invasive sampling protocol and genetic analyses to assess the growth and performance of a small founder population in a fenced reserve. We used these data and recorded life‐history data to compare the population growth and vital rates between the first and second 10‐year periods since founding. We report a decrease in population growth rate and male survival in the second 10‐year period (0.06; 0.89) compared to the first (0.09; 0.97). Genetic diversity (HEXP = 0.405) was low when compared to larger black rhino populations, and average pairwise relatedness was high (0.193). These results suggest that negative genetic consequences and the beginning of density‐dependant growth regulation may be present in this population. This highlights the importance of establishing an evaluation framework for the assessment of small populations of long‐lived mammals in order to inform metapopulation management. [ABSTRACT FROM AUTHOR]

Abstract: Success of animal translocations depends on improving postrelease demographic rates toward establishment and subsequent growth of released populations. Short‐term metrics for evaluating translocation success and its drivers, like postrelease survival and fecundity, are unlikely to represent longer‐term outcomes. We used information theory to investigate 25 years of data on black rhinoceros (Diceros bicornis) translocations. We used the offspring recruitment rate (ORR) of translocated females—a metric integrating survival, fecundity, and offspring recruitment at sexual maturity—to detect determinants of success. Our unambiguously best model (AICω = 0.986) predicted that ORR increases with female age at release as a function of lower postrelease adult rhinoceros sex ratio (males:females). Delay of first postrelease reproduction and failure of some females to recruit any calves to sexual maturity most influenced the pattern of ORRs, and the leading causes of recruitment failure were postrelease female death (23% of all females) and failure to calve (24% of surviving females). We recommend translocating older females (≥6 years old) because they do not exhibit the reproductive delay and low ORRs of juveniles (<4 years old) or the higher rates of recruitment failure of juveniles and young adults (4–5.9 years old). Where translocation of juveniles is necessary, they should be released into female‐biased populations, where they have higher ORRs. Our study offers the unique advantage of a long‐term analysis across a large number of replicate populations—a science‐by‐management experiment as a proxy for a manipulative experiment, and a rare opportunity, particularly for a large, critically endangered taxon such as the black rhinoceros. Our findings differ from previous recommendations, reinforce the importance of long‐term data sets and comprehensive metrics of translocation success, and suggest attention be shifted from ecological to social constraints on population growth and species recovery, particularly when translocating species with polygynous breeding systems. [ABSTRACT FROM AUTHOR]

Historical evidence of tuberculosis ( TB) affecting primarily captive rhinoceroses dates back almost two centuries. Although the causative Mycobacterium tuberculosis complex ( MTC) species has not been determined in many cases, especially for those that occurred before bacterial culture techniques were available, the spectrum of documented reports illustrates the importance of TB as cause of morbidity and mortality in different rhinoceros species across continents. In more recent years, sporadic suspected or confirmed cases of TB caused by Mycobacterium bovis ( M. bovis) have been reported in semi-free or free-ranging rhinoceroses in South Africa. However, the true risk TB may pose to the health and conservation of rhinoceros populations in the country's large conservation areas where M. bovis is endemic, which is unknown. Underlying the current knowledge gap is the lack of diagnostic tools available to detect infection in living animals. As documented in other wildlife species, TB could establish itself in a rhinoceros population but remain unrecognized for decades with detrimental implications for wildlife conservation at large and should such animals be moved to uninfected areas or facilities. This paper reviews the current state of knowledge regarding TB in rhinoceros including critical gaps that need to be addressed to effectively assess the threat that this disease may present to rhinoceros. [ABSTRACT FROM AUTHOR]

Although Salmonella spp. infection has been identified in captive and free-ranging rhinoceros, clinical cases in black rhinoceros ( Diceros bicornis) calves have not been described. This case series describes clinical salmonellosis in four black rhinoceros calves. Two calves developed self-limiting diarrhea, recovering after treatment. The other two cases were fatal. One of the fatal cases had a short clinical course, whereas the other case was protracted, with signs reflecting multiple organ system involvement. In all cases, diagnosis was by fecal culture and/or quantitative polymerase chain reaction. A variable clinical presentation, which is typical for salmonellosis in domestic hoofstock, was a feature of these rhinoceros cases. Similarly, postmortem pathology in black rhinoceros calves was consistent with domestic neonatal ungulates with salmonellosis. Potential predisposing factors for infection were considered to be primiparity of the dam and failure of passive transfer in the calf. The case investigation included attempts to identify the source of infection, which was aided by organism serotyping. In one case, the patient's dam and another conspecific in the facility were shown to be asymptomatic shedders of the organism strain responsible for disease in the calf. Further surveillance of captive rhinoceros Salmonella spp. carrier status is needed to inform screening recommendations for this taxa. [ABSTRACT FROM AUTHOR]

Through the use of operant conditioning, the authors developed a technique to facilitate obtaining blood samples from a black rhinoceros diagnosed with idiopathic epilepsy. The technique involved operant conditioning to facilitate venipuncture of the transverse facial vein, at an anatomic landmark on the lateral side of the face ventral to the medial canthus of the eye, and dorsal to the lateral commissure of the mouth. The investigators used standard operant conditioning protocols to train the animal for desensitization to a needle puncture in the facial vein. Blood samples obtained from the facial location were free of excessive hemolysis and allowed for large volumes to be collected. The procedure was well-tolerated by the rhinoceros and could be performed regularly without complication. Zoo Biol. 35:570-573, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In 2016, an emaciated black rhinoceros (Diceros bicornis) was found in Kruger National Park, South Africa. An interferon-γ response was detected against mycobacterial antigens, and lung tissue was positive for Mycobacterium bovis. This case highlights the risk that tuberculosis presents to rhinoceros in M. bovis–endemic areas.

Iron overload disorder (IOD) is a significant health issue for captive black rhinoceros ( Diceros bicornis). Measurement of serum ferritin with a validated rhinoceros ferritin ELISA has been used extensively to detect animals in U.S. zoos that are at risk of developing IOD. However, there is limited information on serum ferritin levels in free-ranging black rhinoceros using this same assay. Serum ferritin, iron, and gamma-glutamyl transpeptidase (GGT) were determined in 194 black rhinoceros from southern Africa. Mean ferritin in free-ranging black rhinoceros (290.54 ±247.4 ng/ml) was significantly higher than in free-ranging white rhinoceros (64.0 ± 102.4 ng/ml) sampled in this study from Kruger National Park, South Africa. However, there were no significant differences between genders or age groups. Ferritin values varied with geographical location of the black rhinoceros, although this was not clinically significant. Serum iron values were also higher in black rhinoceros (40.4 ± 19.1 μmol/L) compared to white rhinoceros (29.7 ± 10.7 μmol/L). There was no association between ferritin and GGT. This study provides serum ferritin, iron, and GGT values from free-ranging black rhinoceros that can be used for as comparative target values for captive animals. [ABSTRACT FROM AUTHOR]

A hand-reared, 53-kg, female, 30-day-old black rhinoceros ( Diceros bicornis) calf presented for magnetic resonance imaging and computed tomography after demonstrating neurologic signs. The rhino was premedicated intramuscularly with butorphanol and midazolam, yielding satisfactory sedation. Induction was achieved using intravenous propofol until the trachea could be intubated. Anesthesia was maintained with sevoflurane in 100% oxygen (mean end-tidal concentration of 2 ± 0.5%). Mean values recorded during anesthesia included were heart rate, end-tidal carbon dioxide, respiratory rate, noninvasive blood pressure, and pulse oximetry. A balanced electrolyte solution of 10 mL/kg per hour was given intravenously. It was concluded that anesthesia was safely induced and maintained with a combination of butorphanol, midazolam, propofol, and sevoflurane. Total anesthesia time was 3 hr, with no perianesthetic complications and an uneventful recovery. [ABSTRACT FROM AUTHOR]

Recurrent eosinophilic granuloma (EG) in two captive eastern black rhinoceros ( Diceros bicornis michaeli) was effectively managed with glucocorticoids and antihistamines. The first case was a female and the second case was a male. The animals were housed at separate institutions and initially presented with hemorrhagic oral lesions. Multifocal lesions occurred in the second case. Multiple biopsies were taken from each animal, all of which were consistent with EG. Each animal was anesthetized multiple times for surgical treatment but experienced frequent recurrence. Due to lack of response to therapy and the risks and adverse events associated with repeated anesthesia, medical treatment was initiated in both cases using a tapering dose of oral dexamethasone. The lesions dramatically improved, but would recur frequently after treatment. Hydroxyzine, an oral antihistamine, greatly reduced the incidence and severity of the lesions. Medical management with glucocorticoids and antihistamines minimized stressful anesthetic events in both cases and contributed to the successful management of this recurrent disease. The exact pathogenesis of EG in black rhinoceros remains unknown but response to antihistamines suggests an allergic etiology. [ABSTRACT FROM AUTHOR]

What determines the abundance of parasites is a central question within epidemiology. Epidemiological models predict that density-dependent transmission has a principal influence on parasite abundance. However, this mechanism is seldom tested in macroparasites, perhaps because multiple, comparable populations of the same host-parasite relationship are rare. We test the influence of a range of factors on parasite abundance across 18 populations of black rhinoceros ( Diceros bicornis) in South Africa. Here we show that host density strongly predicts parasite abundance at the population level for both directly and indirectly transmitted parasites. All other models were not supported. The surprising influence of a single key factor, host density, within a complex ecological system demonstrates the validity of simple epidemiological models. Establishing this previously assumed relationship between host density and parasite abundance has major implications for disease control and parasite ecology. For instance, it is central to the idea of population density thresholds for parasitism, below which a parasite would become extinct. Density-dependent transmission is also essential for calculations of the basic reproductive number, and the hypothesis that parasites may regulate host population size. [ABSTRACT FROM AUTHOR]

The article presents a case study of a captive male black rhinoceros (Diceros bicornis) diagnosed postmortem with mycobacterium tuberculosis (TB) infection. An epidemiologic investigation was performed using retrospective analyses of medical records, serum samples, and testing of contacts. It supports the use of serological test in diagnosing TB.

Despite an on-going struggle to conserve the endangered black rhinoceros ( Diceros bicornis) since the 1980s, huge capital investment and several genetic surveys, the level of genetic structure and connectivity among populations in southern Africa is not well understood. Here, we undertake a major population genetic study of black rhinoceros in the Zimbabwe Lowveld, an area inhabited by over half of that country's original Zambezi descendants plus one large population sourced from the relict KwaZulu stock of South Africa. Using nuclear microsatellite and mitochondrial DNA data, we found much higher levels of genetic diversity in the indigenous Zimbabwean populations, where observed multilocus heterozygosity was 0.54 versus 0.40 in KwaZulu, and maternal haplotype diversity was 0.77 versus 0.03. We show, for the first time, that both gene pools can be differentiated from each other on the basis of nuclear markers. This, along with the discovery of recent gene flow between all Lowveld populations, suggests that Zimbabwean and South African gene pools were prehistorically connected. [ABSTRACT FROM AUTHOR]

This study tested the hypothesis that the black rhinoceros browses more on termitaria than off termitaria vegetation due to elevated soil and foliar nutrient levels on termitaria. We investigated the role of termitaria in providing nutrient-rich forage for the black rhinoceros, by comparing the preference (selection ratio) for vegetation occurring on and off termitaria, and then testing its relationship with foliar nutrient concentrations. Soil nutrients, bite intensity, tree species diversity, vegetation density, canopy cover and basal area were also surveyed on and off termitaria. We sampled 25 termite mounds together with their corresponding control plots in Chipinge Safari Area, Zimbabwe. Soil and foliar N, P, K, Ca and Na concentrations were greater on termitaria than off termitaria, with approximately twice the concentration of these nutrients. Browse preference followed the between-site differences in soil and foliar nutrient concentrations, with higher selection ratios and bite intensities for vegetation on termitaria than off termitaria. Diospyros quiloensis was the most preferred browse species whilst Combretum imberbe, Kigelia africana and Strychnos innocua were the least. In conclusion, the black rhino preferred vegetation on termitaria to that in the surrounding matrix, and utilization of vegetation can be influenced by the soil substrate on which tree species grow. [ABSTRACT FROM PUBLISHER]

Ensuring the persistence of populations of endangered species requires an understanding of, and response to, the causes of population declines. Species occurring in small populations are vulnerable to stochastic problems that are environmental, demographic, or genetic in nature and can reduce survival as much as the deterministic threats of habitat degradation. Critically endangered black rhinoceros ( Diceros bicornis) populations declined throughout Africa since 1960, with numbers steadily increasing at a continental level, but remaining lower than three generations ago. However, size, demographics, trends, and factors affecting these, are poorly known. We used 18 years (1990-2008) of long-term sightings data from Ithala Game Reserve, Kwa Zulu- Natal, South Africa, to determine population estimates, growth rate and fecundity over time, as well as sex and age structure and age-specific probabilities of survival. Calf survivorship between the ages of 0 and 1 year was 74% for females and 94% for males. Age-specific survivorship for both sexes was significantly higher from yearling to subadult age-classes (1-6 years) than for adults (7-30 years). The most frequent cause of mortality was attributed to unknown causes while fighting injuries was recorded as the second most common cause of mortality, particularly among subadult and adult males. There was no significant difference in the sex ratios at birth, although the proportion of females in the population was 0.58. There was strong evidence for density-dependent regulation, with density in conception year a key driver of population performance (birth rate). The population does not appear to be at ecological carrying capacity; however, social effects are delaying conception. To mitigate density-dependent social effects, we recommend an adaptive management strategy of pre-selecting individuals for removal from the reserve, so as to maintain stability in the social organization of the population. [ABSTRACT FROM AUTHOR]

The article focuses on a study which observed that previously that end-expired carbon dioxide decreased when immobilized black rhinoceroses in Namibia. Study immobilized 21 wild black rhinoceroses with hypoxemic and had lactic and respiratory acidemia. Study found that positioning immobilized rhinoceroses in lateral recumbency does not confer any advantage over sternal in terms of ventilation.

Despite a now-extensive literature on sex allocation, facultative sex allocation in mammals remains controversial. We studied the complete birth-sex record of a black rhinoceros ( Diceros bicornis minor) population from its reintroduction in 1986 through 2008. Neither explicit models of birth sex as Bernoulli trials nor mixed-model logistic regression yielded evidence for an influence on birth sex of birth sequence, maternal identity, year of conception, rainfall, population size, maternal age, or adult sex ratio despite a small female-biased population birth sex ratio that nevertheless appears to be unusual for black rhinoceros. One interpretation of our results is that our study population did not facultatively control birth sex, either because black rhinoceros cannot or because environmental and demographic circumstances did not elicit conditions that favor pronounced adaptive control of birth sex in this population. Alternatively, variation in sex allocation could have occurred in a manner not captured by our modeling or at a scale we could not probe. If the observed female bias is not purely stochastic, it may result from the perturbed age structure of the introductions, which was biased toward subadults. [ABSTRACT FROM AUTHOR]

Abstract: The seminiferous cycle of the rhinoceros was investigated for the first time using testicular tissue from captive white (Ceratotherium simum, n =2) and black (Diceros bicornis, n =1) rhinoceroses. Stages of the seminiferous epithelial cycle were characterised using the tubular morphology method and relative frequencies of each stage determined. This method allowed for the identification of eight stages of cellular associations characteristic of the seminiferous cycle in white and black rhinoceroses. The eight stages of the seminiferous cycle observed closely approximated the stages previously described for the domestic horse (Equus caballus). Premeiotic (stages I–III), meiotic (stage IV) and postmeiotic (stages V–VIII) represented 44.8%, 5.3% and 49.9% of the seminiferous cycle respectively. [Copyright &y& Elsevier]

The taxonomy of African black rhinoceros ( Diceros bicornis) remains unresolved. Maintaining levels of genetic diversity and species rescue by reintroduction and restocking requires its resolution. We compared the sequences of the mitochondrial DNA (mt DNA) control region for a total of 101 D. bicornis from three subspecies: D. b. minor, D. b. michaeli and D. b. bicornis. A single unique haplotype was found within the 65 D. b. minor samples from Kwa Zulu- Natal ( KZN) Province, South Africa, 55 of which came from Hluhluwe-i Mfolozi Game Park ( HiP) and Mkuzi Game Reserve ( MGR) source populations. However, six different haplotypes were represented in eleven D. b. minor samples from Zimbabwe. Similarly, published autosomal microsatellite data indicate low levels of diversity within the KZN D. b. minor populations. The low levels of mt DNA diversity within the KZN metapopulation point to the possible need for genetic supplementation. However, there is a need to determine whether the low levels of genetic variation within KZN D. b. minor are a result of the recent bottleneck or whether KZN historically always had low diversity. [ABSTRACT FROM AUTHOR]

To assist with identifying land for reintroduction, a habitat suitability model (HSM) for black rhinoceros (Diceros bicornis) was developed in the arid Augrabies Falls National Park, South Africa, from records of sightings, feeding trails and dung middens. Logistic regression and Bayesian Information Criterion were employed to construct and select the best HSM from >35 eco-geographical variables. The modelled and the observed distributions of black rhinos did not differ (P = 0.323) and k-fold cross-validation confirmed the model's ability to predict the distribution of independent data. The HSM consisted of five variables: availability and equitability of three preferred foods, distance to roads, habitat heterogeneity, slope and shade. The variables 'distance to water' and 'rockiness' were also included in the confidence set of models. Only 50% of the study area had a habitat suitability exceeding 11%, but featured 89% of rhino locations. Of 10 vegetation communities, two with high volumes of favourite foods were preferred. Feeding areas with a high density of preferred food plants were also highly preferred. The riverine vegetation community was not preferred, because its abundant browse was not of the preferred species. The apparent avoidance of roads warrants more research and the attention of park managers. [ABSTRACT FROM AUTHOR]

The article presents a study related to the link between insulin resistance and iron overload disorder in browsing rhinoceros through the use of an equine model. It informs that the iron overload disorder are present in captive rhinoceros but has not been documented in the wild. In this study, the nutritional requirements of horses are used as a guide for rhinoceros because they have similar gastrointestinal tracts. The study concluded that on evaluating responses by gender a significant correlation exists only for females influenced by one insulin resistant individual. It is found that there is a potential link between insulin resistance and body stores of iron in captive browsing rhinoceros.

The article presents a biochemical study of serum samples collected from 20 black rhinoceros, Diceros bicornis from six different areas in South Africa to analyze its iron values. It compares the serum iron, biochemical values related to liver health and other trace mineral values such as copper and zinc in free-ranging black rhinoceros to determine significant trends of iron storage disorder of captive black rhinoceros. In the study, serum iron results from 20 black rhinoceros were plotted based on age category. It is concluded that the free-ranging black rhinoceros are subjected to the same potential issues that occur in captive rhinoceros such as progressive accumulation of iron with age and variation with location-based dietary intake.

The article focuses on the measurement and comparison between the serial rectal and muscle temperatures in immobilized free-ranging black rhinoceros in Ethosha National Park in Namibia. Both temperatures are found to correlate with each other through pairwise comparisons. The tendency of both temperatures to equilibrate is noted as immobilization time increases and as the ambient temperature increases at time of immobilization, the average temperature of the animal also increases. Methods for monitoring the temperatures are deemed important to integrate into anesthetic monitoring protocols.

Background: Habitat and food supply loss and disruption, together with man's pursuit of the animal's unique horn pose significant threats to the charismatic rhinoceros. Filarial worms have been thought to cause cutaneous lesions in black rhinoceros (Diceros bicornis) in Kenya and South Africa, but never in white rhinoceros (Ceratotherium simum) in the wild, despite the fact that the two species live often in close proximity. Stephanofilaria dinniki has been implicated in the past as the causal agents for such lesions. Findings: In this paper we report a putative filariosis outbreak in both black and white rhinos at Meru National Park in Kenya. Four black and five white rhinos were affected by various degrees of filarioid-like lesions, while apparently all sympatric wild and domestic animals were filarial worm-free. Affected rhinos were captured and successfully treated. Comparison between the epidemiological aspects of white and black rhinoceros filariosis, and the possible relations between this outbreak and annual seasons, the presence of oxpeckers and other host species are discussed. Conclusions: Our study highlights (i) that filarial infection is not restricted to black rhinos, but it affects both rhinoceros species, and (ii) the importance of the earlier detection and immediate treatment (capture-treat and release) of filarioid infections, which is of pivotal interest for wildlife conservation, and especially the endangered and isolated white and black rhinoceros populations. [ABSTRACT FROM AUTHOR]

Abstract: Mortality rates are high among captive African black rhinoceroses (Diceros bicornis), due to increased susceptibility to disease. The ability to rescue genetic material from individuals that die unexpectedly represents a practical approach to assist ex situ conservation efforts. The objectives of the present study were to attempt postmortem oocyte recovery from ovaries of African black rhinoceroses (N = 6) and to test the efficacy of equine protocols for rhinoceros oocyte IVM and IVF using cryopreserved rhinoceros sperm. The interval from ovary removal to oocyte recovery was 25.3 ± 13.9 h (mean ± SD). Ovaries were transported at 4 °C or 22 °C and effects of temperature on postmortem oocyte competence was evaluated. Numbers of oocytes collected per female averaged 15.8 ± 6.9. In total, 95 oocytes were recovered. Of these, 85 were inseminated using homologous sperm and 10 were inseminated using heterologous sperm. Overall, substantial numbers of viable oocytes were retrieved from African black rhinoceros ovaries 1 to 2 days postmortem from ovaries stored at ambient temperature. A proportion of these oocytes matured and underwent penetration and fertilization by heterologous or homologous frozen-thawed rhinoceros sperm. The reproductive competence of postmortem oocytes was further demonstrated by development of a single two-cell embryo. Despite the need for further refinements, gamete rescue in the rhinoceros has promise for producing rhinoceros embryos, as well as testing sperm functions in vitro. [Copyright &y& Elsevier]

Small population sizes provide several challenges to conservation managers seeking to ensure species persistence and illustrating conservation success. Black rhinoceros, Diceros bicornis minor, epitomizes these challenges. During October 2008 we used block surveys, estimates of availability and observer bias to calculate landscape-specific black rhino abundances in the southern parts of Kruger National Park, South Africa. We assigned age and sex to individuals, extracted an age distribution, and estimated survival and fecundity given the population growth derived from historical strip transects. The block counts, corrected for 90.3% availability bias with observers missing 3.8% of those, predicted that 627 (95% CI: 588-666) black rhinos resided in the study area. The population increased at 6.75% per annum, the result of high survival and an estimated inter-calving interval of 2.45 years. Age distributions and population growth predicts that subadult males and females have the lowest annual survival, while dependent calves and adults have the highest annual survival. Precise estimates can be obtained with a 20% study area coverage using block counts. This gives coefficient of variances allowing detection of 5% growth from surveys every two years. Detecting 2% annual decline requires bi-annual surveys for 6 years. Our results illustrate that black rhinos are performing well in Kruger National Park. [ABSTRACT FROM AUTHOR]

Poaching and habitat destruction across sub-Saharan Africa brought the black rhinoceros ( Diceros bicornis) close to extinction. Over the past few decades, however, one of four subspecies, D. b. bicornis, has experienced a significant population increase as a consequence of its protection within Etosha National Park (ENP), Namibia. We report here on the level and spatial distribution of black rhinoceros genetic diversity within ENP. Using nine microsatellite loci, genetic variation was assessed from 144 individuals. Our results are consistent with the observation of lower levels of genetic diversity in D. b. bicornis, when compared to D. b. michaeli, but greater diversity when compared to D. b. minor. We also showed that ENP's black rhino genetic diversity is well represented in Waterberg National Park, originally founded with ENP individuals. We found no genetic signature of a recent bottleneck in ENP, however, suggesting that the genetic diversity within ENP has not been adversely affected by the recent severe population decline. Using Bayesian clustering methods, we observed no significant population structure within ENP, but positive spatial genetic correlation is observed at distances up to 25 km. This relationship exists in females but not males, suggesting reduced dispersal among females, the first evidence of limited female dispersal or philopatry in any species of rhinoceros. [ABSTRACT FROM AUTHOR]