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118 AND

Int. Yb. (2006) 40: 118–129 © The Zoological Society of London

An integrated management strategy for the conservation of Eastern Diceros bicornis michaeli in

R. AMIN1, B. OKITA-OUMA2, K. ADCOCK3, R. H. EMSLIE3, M. MULAMA2 & P. PEARCE-KELLY1 1Zoological Society of London, Regent’s Park, London NW1 4RY, , 2Kenya Wildlife Service, PO Box 40241-00100, Nairobi, Kenya, and 3IUCN/SSC African Rhino Specialist Group, Box 1212, Hilton 3245, KwaZulu-Natal, South E-mail: [email protected]

At time of writing Kenya holds c. 84% of the Brooks, 1999; Brooks, 2002; Mulama & remaining in situ population of Critically Endan- Okita-Ouma, 2004) (Fig. 1). At the end of gered Diceros bicornis michaeli. The Kenyan 5 Black Rhino Conser- 2003 the c. 450 Eastern black rhinoceros vation and Management Strategy has given highest in Kenya (c. 84% of the total in situ popu- priority to the biological management of the subspe- lation) are spread across 14 sanctuaries, cies in order to help achieve and maintain rapid reserves and national parks, with habitats metapopulation growth to increase rhinoceros num- bers. Specific training and capacity building in mon- ranging from dense to semi-arid itoring of rhinoceros, from collection of field data to scrubland (Fig. 2; Plate 1). The Eastern status reporting, have been implemented. Procedures black rhinoceros is considered Critically to assess ecological carrying capacity for Eastern Endangered by IUCN (2004). This drastic black rhinoceros habitat have been developed to help establish new viable populations and to opti- decline was initially the result of culling in mize the management of existing sanctuaries, some order to clear land for agriculture and was of which face loss of suitable habitat owing to com- exacerbated by intense , which petition for resources between rhinoceros and other occurred both within and outside the browsers. The management objective is to maintain national parks and reserves. In 1984, in rhinoceros populations below the ecological carrying capacity of a reserve in order to increase reproduc- response to this rapid decline, Kenya tion in ‘donor’ populations as well as the trans- implemented a strategy aimed at restoring location of to create new populations with the rhinoceros population. The strategy the potential for rapid growth. The conservation included the establishment of sanctuaries, value of establishing site-level support relationships is also discussed. Kenya, for the first time since the collaboration between the Kenya Wildlife 1970s, achieved a growth rate of q5% over the Service (KWS) and the private and com- period 2004 and 2005 (the national goal is to increase munity sectors, heightened protection numbers by at least 5%). through increased law enforcement, Key-words: biological management, capacity improved staff densities and capacities, building, eastern black rhinoceros, ecological revision of staff remuneration and drastic carrying capacity (ECC), population estimation, changes to the management of national rhinoceros monitoring, status reporting parks. This strategy halted the decline of the In 1970 the Eastern black rhinoceros rhinoceros population in Kenya and since Diceros bicornis michaeli population in 1987 numbers have increased, albeit Kenya was c. 20 000 but by the late 1980s slowly, at an average annual growth rate this population numbered Q400 animals of Q5%. However, if it had been possible (Foose et al., 1992; Anon., 1993; Emslie & to achieve even the AfRSG minimum REVIEW: EASTERN BLACK RHINOCEROS INTEGRATED MANAGEMENT STRATEGY 119

Fig. 1. Eastern black rhinoceros Diceros bicornis michaeli trend across Africa and in Kenya 1970–2003, in a logarithmic scale, showing the sharp decline and slow recovery. Data from Anon. (1993), Foose et al. (1992), Emslie & Brooks (1999), Brooks (2002) and Mulama & Okita-Ouma (2004). acceptable (Emslie & Brooks, 1999) meta- heterozygosity, by ensuring maximum population growth rate of 5% per annum rate of gene transfer to future generations the population could have still grown (Gilpin & Soule´, 1986). In recognition of significantly (Fig. 3). The value of 5% was the importance of striving to maintain chosen as the minimum acceptable growth rapid growth to retain genetic diversity, rate as it is only just over half of r-max Kenya’s current Black Rhino Conserva- (9%) and should be attainable. In practice, tion and Management Strategy places one would hope to achieve higher rates of greater emphasis on improving metapo- increase (6·5–9%). Given an expanding pulation performance through effective population with a young age structure in biological management (Anon., 2003) good habitat, one can temporarily achieve (Fig. 4). The strategy advocates managing even higher rates of growth (10%+). As it for metapopulation growth of at least 5% is, even at the 5% rate it would take per annum and preferably higher. To 30 to achieve the target population achieve this, specific capacity and proce- level of 2000 animals; a level that could be dural mechanisms were urgently required achieved in 15 years if annual metapopu- in: (1) field monitoring of rhinoceros, lation growth rate could increase to 9% data collection, analysis and reporting, (i.e. near the biological maximum growth (2) production of standardized annual rate for non-sex-biased black rhinoceros status reports that assess the numbers, populations). Large, rapidly breeding performance and population dynamics of healthy populations not only provide the Eastern black rhinoceros populations in best possible insurance against future Kenya in order to aid biological-manage- poaching losses but also preserve genetic ment decision making and (3) assessment diversity, or at least minimize loss of of habitat conditions and ecological 120 ELEPHANTS AND RHINOCEROS carrying capacities in fenced sanctuaries, monitoring data are used to provide esti- allowing the management of habitats by mates of population size, age and sex adjusting rhinoceros and other browser structures, calving rates (i.e. 8 breeding population densities, and fire regime performance), mortality rates (by age and where relevant, and assisting in develop- sex), and the distribution and movement ment of new viable populations. Several of rhinoceros. This information is used to Kenyan sanctuaries have experienced or gauge the performance of each population are experiencing high densities of rhino- and guide biological-management deci- ceros and competing browsers, or very sion-making processes, such as introduc- high/low fire frequencies, and there is a tions and removals, to realize the national risk of the long-term productivity of the conservation strategy of increasing the habitat being negatively affected. total rhinoceros population as rapidly as possible. The individual identification of rhino- MONITORING FOR MANAGEMENT ceros requires properly skilled and moti- In order to monitor rhinoceros popu- vated observers, a system of strict control lations, Kenya has implemented a on data quality at observer and data- standardized programme of patrols to recording levels, and the support of obtain information on rhinoceros sight- the wider conservation-management ings. Rhinoceros are identified individu- structure. ally and registers of the features of individual animals are maintained. Where needed, recordings are also made of sight- DEVELOPING MONITORING CAPACITY ings of ‘clean’ rhinoceros (i.e. those that Training A formalized training pro- are not individually recognizable). These gramme for personnel can greatly

Fig. 2a. As at end of 2003 there were c. 540 and c. 170 Eastern black rhinoceros in situ and ex situ, respectively (AfRSG, 2004); b. Kenya is the stronghold of D. b. michaeli, with 458 rhinoceros in the population, as at end of 2003, mostly within sanctuaries, both in protected areas and on private land, and in a free-ranging population on county-council land. has an estimated 42 Eastern black rhinoceros, mostly in free-ranging populations in unfenced protected areas and a few in one sanctuary. and hold relict populations of one (in a protected area) and two to four (on community land) animals, respectively. As at 2003 had an estimated 36 D. b. michaeli, of predominantly Kenyan origin, out-of-range on private land. REVIEW: EASTERN BLACK RHINOCEROS INTEGRATED MANAGEMENT STRATEGY 121 accelerate the process of acquiring high staff turnover. Standardized data collec- standards of observational and data-col- tion, including the use of the continental lection skills. The project, funded through rhinoceros ageing and body-condition the UK government’s Darwin Initiative, assessment systems, also means results can has implemented a sustainable field-staff be compared between parks, including training programme and, at the time of those in other range countries (Adcock & writing, 24 officers from national parks Emslie, 2004). and sanctuaries have been trained as accredited rhinoceros-monitoring instruc- Tools and procedural mechanisms The tors in the continental-wide modular Kenyan Rhino Programme has imple- African Rhino Specialist Group (AfRSG) mented data quality-control procedures in course. These field instructors are, in turn, all its reserves to ensure that the data are training the c. 200 rangers in the field on collected on an on-going basis and are of an on-going basis. The process of testing the best possible quality. Field rangers and accrediting both trainers and trainees have been trained to approach and has helped institutionalize the process and observe rhinoceros, and accurately com- provide formal recognition to those who plete the standardized sighting forms gain accreditation. (Fig. 5). This information is then checked A significant advantage of this by experienced accredited observers and approach is that staff can be trained the sightings are classified in accordance where they are located, thus saving time with the ‘ID’ master files, which are con- and money and minimizing daily opera- tinually updated by the field officers. tional impact on the field teams. In addi- The extensive sets of field data are tion, with continuous teaching of the stored and analysed using a compre- modules it is possible to maintain consis- hensive geographic information database tency as well as deal with the inevitable management system (KIFARU). Standard-

Plate 1. An ear-notched and, thus, recognizable Eastern black rhinoceros Diceros bicornis michaeli on the plain in National Park, Kenya. ZSL, London, UK. 122 ELEPHANTS AND RHINOCEROS

Fig. 3. Estimates of Eastern black rhinoceros populations after 1%, 5% and 9% growth rates. Since 1987 popu- lation numbers of the Eastern black rhinoceros have increased at an annual rate of 1% and, without biological management to improve population growth, it will take 170 years to reach the target population of 2000 rhino- ceros. However, if population growth rates in Kenya increased to 5% per annum, this target population will be achieved in 30 years and at a rate of 9% the target population could be achieved 15 years earlier than this. ized monthly reports provide key informa- Park and Ngulia Rhino Sanctuary in tion, such as sighting frequencies of Tsavo West National Park, and this individual rhinoceros, patrol movements makes it difficult to estimate population and the availability of manpower size and structure accurately. However, resources, which are used to optimize these areas are important to the long-term deployment of patrols and analyse popu- conservation of rhinoceros in Kenya. lation performance (Amin et al., 2001). Tsavo East and West National Parks are over 20 000 km2 in total and have a very Monitoring practicalities Tsavo East high capacity to assimilate rhinoceros National Park, Kenya, is vast from smaller, overstocked sanctuaries and (c. 11 000 km2) and the relatively low parks. This area used to have over 6000 numbers of monitoring staff, coupled with black rhinoceros before the poaching international boundary-related problems, onslaught in the 1970s and 1980s. such as infiltration of firearms from neigh- The practical issues of achieving effec- bouring countries, have made the effective tive monitoring in these areas need to be monitoring and security of the rhinoceros addressed before such moves can take population in this area difficult. place. A number of initiatives are being Rhinoceros are rarely sighted during developed and implemented. For example, the day in the difficult terrain of the the dry season full-moon night census is Chyulu-Hills National Park, or in the being improved using better planning and dense vegetation of Aberdare National equipment to obtain more comprehensive REVIEW: EASTERN BLACK RHINOCEROS INTEGRATED MANAGEMENT STRATEGY 123

Fig. 4. The Conservation and Management Strategy for Eastern black rhinoceros sets six strategic objectives to achieve the national goal of increasing numbers of the to 1000 by 2020 and eventually achieving the target population of 2000 in natural habitat in Kenya (Anon., 2003). population information in the Tsavo West ties, and allocate law-enforcement efforts National Park Ngulia Rhino Sanctuary. appropriately in order to protect these Systems to achieve more effective night- populations. monitoring programmes are also being developed in Aberdare and Chyulu-Hills National Parks. A combination of direct Estimating population size A problem and indirect methods for deriving indices experienced in many Kenyan reserves is of rhinoceros abundance, and relating that an increasing number of animals that these to indices of patrol and poaching are not individually recognizable (i.e. activities, are also being considered to clean). Young clean rhinoceros become track population distributions and densi- unrecognizable once they leave their mothers. In the past, population estimates have only been based on identifiable animals, which provided a minimum index rather than an estimate of the true population size. Reliable population-size estimates (within 90% of the true total) are required every year (or at least every 3 years) in order to assess how well a population is performing and to manage populations at the metapopulation level. This informa- tion, along with the ecological carrying Fig. 5. One side of the standardized form used to rec- capacity (ECC) estimate of each park and ord details of rhinoceros sightings. sanctuary, can assist programme man- 124 ELEPHANTS AND RHINOCEROS

Fig. 6. K-selected like rhinoceros are likely to have a plateau of nearly constant growth rate (density- independent phase), followed by a ramp of density-dependent decline once the maximum sustained yield level (c. 75% of carrying capacity) has been exceeded.

agers in making decisions that are neces- Annual status reporting National status sary for achieving and sustaining high reporting is a key component of imple- population growth rates. menting the conservation strategy. In the The individual-identification-based past metapopulation performance has monitoring method undertaken in all been ‘averaged out’ in Kenya, thus Kenyan reserves enables the use of performance issues within individual mark–recapture methods for estimating populations may have been overlooked. population size. Field staff are being To promote optimal metapopulation trained on a continual basis to ensure performance it is necessary to look at the accurate recording of sightings of both age and sex composition, calving rates of 88 identifiable and clean rhinoceros, with , and causes and rates of mortality within each population. Reasons for sub- equal emphasis on each sighting. Rhino optimal performance can then be deter- Programme scientists have also been mined and solutions put in place. trained to use the continental level RHINO A formal national-status reporting pro- Bayesian Mark–Recapture software tool gramme has been implemented. Kenya (Emslie & Amin, 2003), which calculates Wildlife Service scientists have been population size using ongoing sighting trained to analyse population perform- data. To improve population estimates all ance data and synthesis of the national- rhinoceros immobilized for translocation status report. At time of writing, 26 or veterinary treatment are ear-notched officers from 13 reserves have also been for identification purposes as standard trained in population data analysis and practice. When resources are available, preparation of annual park-status reports. specific ear-notching exercises are under- The training introduces the principles of taken in areas with a high proportion of status reporting, the concepts around clean animals. metapopulation management and, in REVIEW: EASTERN BLACK RHINOCEROS INTEGRATED MANAGEMENT STRATEGY 125

Fig. 7. Amounts of available browse in each of the nine main Kenyan black rhinoceros areas and the compositional breakdown of this browse by palatability class (i.e. the suitability of the browse component for black rhinoceros). Each class comprises several woody or forb species. Black rhinoceros browse is almost totally within a 0–2 m height range and the browse availability (BA) measure indicates the percentage to which this 2 m layer is filled by browsable plant canopies. BA was sampled by vegetation and a weighted average BA was obtained accounting for the proportional area of each vegetation type within each rhinoceros sanctuary.

particular, the critical need to maintain tality rates and net population growth rapid population growth rates (for demo- rates) (Okita-Ouma, 2004). graphic, strategic and genetic conserva- The individual park reports are synthe- tion reasons). Trainees are shown how to sized and analysed at a national level. The recognize the main causes of poor growth resultant national report interprets and and how to interpret various performance contrasts the status, performance and indicators derived from their own ongoing population dynamics of all Eastern black ground-based monitoring of rhinoceros. rhinoceros populations in Kenya. The The practical application of these indica- feedback from the national-status tors is also highlighted, as trainees are summary report is vital to programme shown how monitoring assists with the managers and staff because it places the decision-making process on sanctuary results of individual-reserve reports into a management and translocations. metapopulation context. The park-level status reports supply Without regular park-level status information on population size, age and reporting and the production of inter- sex structure, translocations and mortali- preted national status report summaries, a ties (including causes), as well as a number problem may also remain undetected far of standardized biological performance longer. The first detailed status reports indicators (age at first calving, percentage have shown clear density dependence in a 88 calving, proportion of adult 88 with number of populations stocked at or near calves, intervals between calving, mor- ECC. The reports have indicated that a 126 ELEPHANTS AND RHINOCEROS number of Kenyan rhinoceros popu- optimal stocking levels may be lower than lations could become donor populations. this during drought years (Fig. 6). In addition, the c. 5% underlying popu- Managing populations at or below 75% lation growth in of ECC should minimize the risk of den- following a period with an average 5% sity-dependent effects negatively affecting annual removal of rhinoceros has pro- populations (e.g. through reduced calving vided empirical support to the Set success and increased mortalities and Percentage Harvesting approach advo- social problems). By reducing densities of cated by the IUCN/SSC’s AfRSG Eastern black rhinoceros and/or other (Emslie, 2001). browsers to below habitat carrying capacity, there is also a reduced risk of negatively affecting the long-term rhino- ESTIMATING ECC OF SANCTUARIES AND ceros carrying capacities of the areas. PARKS Performance in a number of Kenyan Achieving and maintaining a high meta- black rhinoceros populations may be poor population growth rate can only be real- because, in the past, inadequate attention ized if the areas maintaining rhinoceros was given to habitat conditions. Several are not overstocked relative to available reserves face loss of suitable habitat habitat resources. This depends on an esti- through high rhinoceros and competing mate of the ECC of each area. browser densities. It is not easy to measure ECC. Past esti- mates of Eastern black rhinoceros ECC have differed widely in the reports of dif- Kenyan Eastern black rhinoceros ECC ferent observers for the same area. In model The Kenyan Darwin Initiative particular, non-experts have tended to project has developed an ECC model for overestimate substantially the ECC. the region. A similar model has been Nevertheless, it is easy to conceptualize developed for the Southern African range that a habitat at a given point in time states (Adcock, 2001). The estimation of must be able to support sustainably a ECC is multi-faceted. For a given amount limited number of any given of standing ‘browse-plant biomass’ the species. This ECC is probably most browse productivity (growth rate) and closely defined as ‘the maximum number quality are primary determinants of black of animals of a species (sustainably) rhinoceros carrying capacity. Rainfall, supportable by the resources of a specified soil quality and temperature influence area’ (Caughley, 1976; McCullough, these parameters on a broad scale and 1992). Once the ECC is known, existing measures of these factors are also populations can be managed for required. All nine well-established Kenyan maximum productivity and excess animals rhinoceros sanctuaries were surveyed for removed to enhance other populations or browse availability and species composi- establish new populations as necessary. tion (Fig. 7). About 100–150 detailed veg- Estimation of ECC is also a necessary pre- etation plots were assessed in each area requisite for making decisions about the and this information was combined with suitability of an area for establishing a Landsat-7 satellite imagery data to give new subpopulation. For large , overall browse-availability and browse- such as rhinoceros, evidence suggests that suitability index maps. Auxiliary data on the maximum sustainable yield or MSY variables linked to Eastern black rhino- [commonly called maximum productivity ceros ECC were also compiled for the carrying capacity (MPCC)] is c. 75% of areas (game count data, soil and geology estimated (long-term) ECC (Owen Smith, data, long-term rainfall and temperature 1988; McCullough, 1992), although records). REVIEW: EASTERN BLACK RHINOCEROS INTEGRATED MANAGEMENT STRATEGY 127

Monitoring habitats Habitat monitoring near the estimated threshold MSY level, procedures have also been developed, and thus maximizing rhinoceros productivity. park ecologists and monitoring staff are Monitoring the habitat resources as trained in their use. This is important as well as rhinoceros-population perform- ECC will change over time (in the medium ance is useful in the light of changing veg- to longer term) in response to habitat etation in East African ecosystems and the changes, which for Eastern black rhino- influences of competing browsers. Large ceros may be positive (increased browse long-lived animals like rhinoceros may availability of suitable plant species) or also overshoot carrying capacity before a negative [favoured food plants declining potential problem in the population- or growing out of reach, unpalatable performance indicators is identified. species increasing at the expense of more palatable species, increases in alien plants SITE-LEVEL SUPPORT PARTNERSHIPS (e.g. Lantana camara), frequent fire, Experience has demonstrated that even increased grass interference and/or an moderate additional external institution increase in pressure following a site-linked assistance can make a signifi- build-up in numbers of competitive cant impact at the park operational level. browsers (e.g. African elephants Loxo- KWS’s collaboration with The Zoological donta africana, Giraffa camelopar- Society of London (ZSL) and other part- dalis and Cape buffalo Syncerus caffer)] ners to provide additional support for (Plate 2). To be able to update estimates Ngulia Rhino Sanctuary, serves as an of ECC continually, therefore, requires an example of the value of such site-level ini- understanding of browser/browse tiatives. In addition to helping support dynamics, the nature of vegetation infrastructural elements, such as water- changes and their likely impact on ECC. system maintenance and vehicle provi- The estimates of ECC allow managers sion, site-level links can assist the to take 75% of this figure as a ballpark implementation and evaluation of the bio- estimate of the MSY level. Excess animals logical management tools and associated are then removed to maintain densities research areas. Securing out-of-region

Plate 2. Eastern black rhinoceros and African Loxodonta africana (competing browsers) observed during dry-season full-moon night census at Tsavo West National Park, Kenya. ZSL, London, UK. 128 ELEPHANTS AND RHINOCEROS grants (e.g. the UK government’s Darwin of London, Kenya Wildlife Service Director Julius Initiative) is another important benefit Kipng’etich, and staff of all Kenyan rhinoceros reserves for their continued commitment to rhino- that can arise from developing such part- ceros conservation. nerships which, in turn, benefit the wider national programme.

REFERENCES CONCLUSION Adcock, K. (2001): Black rhino carrying capacity The successful development and imple- and performance. In Proceedings of a SADC rhino mentation of the Kenyan Rhino Pro- management group (RMG) workshop on biological gramme’s integrated biological management to meet continental and national black rhino conservation goals: 9–13. Emslie, R. (Com- management and monitoring strategy piler). KwaZulu Natal: Giants Castle . across all rhinoceros parks and sanctu- Adcock, K. & Emslie, R. (2004): Monitoring aries is key to providing decision makers African rhino. In ‘Sandwith’ training course for field with the information necessary to manage rangers (5th edn). Malilangwe, : IUCN/ the national herd at the metapopulation SSC, African Rhino Specialist Group. AfRSG (2004): Working group report. 5. Meta- level. Specific staff training in the field has population planning for D. b. michaeli. In IUCN/ meant that there is a consistency of data SSC-AfRSG meeting. 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