Since 2010, we have been exploring different management options to curtail the decline in hirola numbers. In our quest to save the hirola, we have partnered with the local communities, national and international partners to provide a science-based conservation effort.
The hirola is one of those species hampered in particular by ecological knowledge gaps, weak local involvement and political turmoil along the Kenya-Somalia border. As the hirola occur along the border, past conservation and scientific efforts had been limited to opportunistic field visits. They have also arguably been marginalized by the pressure of cultural barriers between Somalis and other ethnic groups within the borderlands.
To fill in these knowledge gaps, we employ various data gathering techniques such as GPS telemetry, long-term satellite imagery analysis, sight-re-sight data, large predator-proof enclosure (s) and multiyear-multi-sites experiments to provide practical data sets that will inform future management and re-introduction into the historical range.
Currently, we run field-based research in three different hirola concentration areas to identify and fill in these crucial knowledge gaps. Our work focuses on hirola population dynamics, resource selection, and the effects of changing land use in eastern Kenya. Additionally, we are working with local communities to better understand the social factors affecting the survival of the species and the future of hirola conservation in the region.
Some of our current ongoing work include; Hirola re-introduction biology, Hirola Habitat Restoration, Hirola Field Endocrinology, Hirola Diet selection under Environmental uncertainty, Hirola socio-biology and behavior, and Livestock-Hirola diseases interactions and epidemiology.
Our project also focuses on community development, with a particular focus on building local capacity and education initiatives.
Completed Research:
- Understanding how bottom-up and top-down forces affect resource selection can inform restoration efforts. With a global population size of <500 individuals, the hirola Beatragus hunteri is the world’s most endangered antelope, with a declining population since the 1970s. While the underlying mechanisms are unclear, some combination of habitat loss and predation are thought to be responsible for low abundances of contemporary populations.
- Efforts to conserve hirola are hindered by a lack of understanding as to why population density remains low, despite eradication of the viral disease, rinderpest. To elucidate factors underlying chronically low numbers, we examined resource selection and landscape change within the hirola’s native range. Because hirola are grazers, we hypothesized that the availability of open areas would be linked both to forage and safety from predators. We quantified: (i) changes in tree cover across the hirola’s historical range in eastern Kenya over the past 27 years; (ii) how tree cover has influenced resource selection by hirola; and (iii) interactions between tree cover and predation.
- Between 1985 and 2012, tree cover increased by 251% across the historical range of hirola. Tree encroachment was associated with a 98% decline of hirola and elephant Loxodonta Africana populations, a 74% decline in cattle Bos indicus, an increase in browsing livestock by 327%, and a reduction in rainfall.
- Although hirola avoided tree cover, we found no evidence that predation on hirola increased with increasing tree cover.
- Synthesis and applications. Hirola may qualify as a refugee species, in which contemporary populations are restricted to suboptimal habitat and exhibit low survival, reproduction or both. The extinction of hirola would be the first of a mammalian genus on the African continent in modern history. We conclude that contemporary low numbers of hirola are due at least partly to habitat loss via tree encroachment, triggered by some combination of elephant extirpation, overgrazing, drought and perhaps fire suppression. We recommend a combination of rangeland restoration efforts (including conservation of elephants, manual clearing of trees, and grass seeding), increased enforcement of an existing protected area (Arawale National Reserve), and reintroductions to enhance recovery for this endangered species. These efforts will rely on enhanced support from the international conservation community and the cooperation of pastoralist communities with which the hirola coexist ( read more https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2664.12856 )
Abstract
Effective reintroduction strategies require accurate estimates of vital rates and the factors that influence them. The hirola (Beatragus hunteri) is the rarest antelope on Earth, with a global population size of <500 individuals restricted to the Kenya–Somali border. We estimated vital rates of hirola populations exposed to varying levels of predation and rangeland quality from 2012 to 2015, and then built population matrices to estimate the finite rate of population change (k) and demographic sensitivities. Mean survival for all age classes and population growth was highest in the low-predation–high-rangeland-quality setting (k = 1.08 0. ± 03 [mean ± SE]), and lowest in the high-predation–low-rangeland-quality setting (k = 0.70 ± 0.22). Retrospective demographic analyses revealed that increased fecundity (the number of female calves born to adult females annually) and female calf survival were responsible for higher population growth where large carnivores were absent. In contrast, variation in adult female survival was the primary contributor to differences in population growth attributable to rangeland quality. Our analyses suggest that hirola demography is driven by a combination of top-down (predation) and bottom-up (rangeland quality) forces, with populations in the contemporary geographic range impacted both by declining rangeland quality and predation. To enhance the chances of successful reintroductions, conservationists can consider rangeland restoration to boost both the survival and fecundity of adult females within the hirola’s historical range (read more https://esajournals.onlinelibrary.wiley.com/doi/abs/10.1002/eap.1664 )
In developing countries, governments often lack the authority and resources to implement conservation outside of protected areas. In such situations, the integration of conservation with local livelihoods is crucial to species recovery and reintroduction efforts. The hirola Beatragus hunteri is the world’s most endangered antelope, with a population of <500 individuals that is restricted to <5% of its historical geographic range on the Kenya–Somali border. Long-term hirola declines have been attributed to a combination of disease and rangeland degradation. Tree encroachment—driven by some combination of extirpation of elephants, overgrazing by livestock, and perhaps fire suppression—is at least partly responsible for habitat loss and the decline of contemporary populations. Through interviews in local communities across the hirola’s current range, we identified socially acceptable strategies for habitat restoration and hirola recovery. We used classification and regression trees, conditional inference trees, and generalized linear models to identify sociodemographic predictors of support for range-restoration strategies. Locals supported efforts to conserve elephants (which kill trees and thus facilitate grass growth), seed and fertilize grass, and remove trees, but were opposed to livestock reduction. Locals were ambivalent toward controlled burns and soil ripping (a practice through which soil is broken up to prevent compaction). Livestock ownership and years of residency were key predictors of locals’ perceptions toward rangeland-restoration practices. Locals owning few livestock were more supportive of elephant conservation, and seeding and fertilization of grass, while longer term residents were more supportive of livestock reduction but were less supportive of elephant conservation. Ultimately, wildlife conservation outside protected areas requires long-term, community-based efforts that are compatible with human livelihoods. We recommend elephant conservation, grass seeding and fertilization, manual tree removal and resting range from livestock both to enhance the potential for hirola recovery and to build positive rapport with local communities in the geographic range of this critically endangered species. (read more https://zslpublications.onlinelibrary.wiley.com/doi/abs/10.1111/acv.12446 )
The hirola antelope (Beatragus hunteri) is considered to be the most endangered antelope in the world. In the ex situ translocated population at Tsavo East National Park, calf mortality and the critically low population numbers might suggest low genetic diversity and inbreeding depression. Consequently, a genetic study of the wild population is pivotal to gain an understanding of diversity and differentiation within its range before designing future translocation plans to increase the genetic diversity of the ex situ population. For that purpose, we assessed 55 individuals collected across five localities in eastern Kenya, covering its entire natural range. We used the complete mitochondrial DNA control region and microsatellite genotyping to estimate genetic diversity and differentiation across its range. Nuclear genetic diversity was moderate in comparison to other endangered African antelopes, with no signals of inbreeding. However, the mitochondrial data showed low nucleotide diversity, few haplotypes and low haplotypic differentiation. Overall, the inferred low degree of genetic differentiation and population structure suggests a single population of hirola across the natural range. An overall stable population size was inferred over the recent history of the species, although signals of a recent genetic bottleneck were found. Our results show hope for ongoing conservation management programmes and that there is a future for the hirola in Kenya (read more https://academic.oup.com/zoolinnean/advance-article-abstract/doi/10.1093/zoolinnean/zlz174/5700497 ).
The Ongoing Research Project include:
With a global population of fewer than 500 individuals left, every individual hirola matters. For this reason, hirola are currently under a “predator excluded” breeding program. Once a healthy population has been achieved and the primary threat to the survival of hirola tackled, we intend to release the hirola to recolonize their historical range. We are currently doing a study to determine the best conditions for reintroduction.
One of the major reasons for hirola declines was habitat degradation through increased tree cover by approximately 251%. This occurred between 1985 and 2012 leading to approximately 98% decline in the hirola population. In light of this, we are currently undertaking habitat restoration, we are testing different restoration approaches to come up with the best approach to conduct a landscape-level restoration. Based difficulties associated restoring dryland ecosystems we are exploring the use of restoration island as they are specifically designed to use the limited resources within dryland for restoration success
The decline of a species may be attributed to factors including but not limited to physical environmental changes and physiological changes. Since hirola occur mostly on communal land that is degraded, we are looking into how these changes affect the hirola biology. It has been suggested that physiological responses of wild species to human alteration of the environment might have led to or contributed to hirola population declines. We now seek to understand how environmental stressor affects the physiology of hirola in the natural habitat. We are particularly interested in how it affects the recovery of hirola through population recruitment.
While we are actively restoring hirola habitat to expand areas available and increase food for hirola, we are also looking into hirola diet and nutrition to help inform the restoration process for the successful recovery of hirola. In line to this, we are currently undertaking field nutrition study to help us in determining the nutritional and mechanical properties of the hirola foods and the influence on diet choice and energy intake. The hirola foods collected as dried grass samples are to be analyzed for energy, nitrogen, lipids, carbohydrates, and minerals concentrations in the laboratory. The sample collection is cross-seasonal. We are also recording hirola activity profile (feeding, moving, resting, and social interaction) in the process to enable us to know how much time they spend across different rangeland setting, ingestion rate of food items; food processing and ingestion time and also their feeding preferences in terms of plant species and parts of the plants.
Conservation of the critically endangered hirola has been a challenge for years. Worse is the fact that there is so little known about hirola biology. Currently, we are looking to fill the gaps by describing the hirola social behavior and critical biology about their way of life. Such information will be critical in the attempt to draw hirola from the brink of extinction. Among the factors we are looking into include, hirola mating strategies and reproduction, calve survival rate and social interactions.
Hirola share the rangeland with large number of livestock, this is because most of the locals in this region primarily depend on pastoralism. A disease outbreak in livestock population could potentially be transmitted to wildlife populations and vice versa. Therefore, we seek to understand origin, reserves and path of disease transmission between livestock and wildlife populations. This will help us manage disease outbreaks and limit the impact of diseases within this region, consequently preventing potential loss of hirola through disease as observed in the past with the outbreak of rinderpest that devastated the hirola population in the 1980s.