WALKING WITH AFRICAN WILDLIFE

Transcription

1 Earthwatch Field Report 2014 Field Season WALKING WITH AFRICAN WILDLIFE PI: Dr. Dave J. Druce REPORT COMPLETED BY (NAME): Dr. Dave J. Druce PERIOD COVERED BY THIS REPORT: July to September 2014 Photo courtesy of Earthwatch volunteer Jeff Wilson 1

2 Dear Earthwatch Volunteers, The 2014 fielding season was a great success as a result of your time, legs, eyes, and expertise in completing a massive number of transects throughout Hluhluwe-iMfolozi Park (HiP). Each transect that you walked was repeated between 11 and 14 times during the season, with 17,946 individual species documented in 3,532 different sightings! Without you coming to HiP, we would not have been able to repeat the transects as many times as we did, which provides us with a large enough sample size to produce accurate estimates. One of the main reasons for conducting this census is to monitor long-term trends in the large herbivore population and to use the information in more effectively managing these species within a "small" (960 km 2 ), enclosed protected area. In November 2014, we held the annual Animal Population Removals meeting in Hluhluwe. The aim of this meeting is typically to debate population estimates, assess population trends, and determine offtakes of each species for the following year. As you can imagine, this is a very important meeting and requires excellent information. The park management team was very impressed with the amount of data collected during the census in Unfortunately, all of the species, with the exception of buffalo, white rhino and black rhino, are decreasing in number. As a result, only white and black rhinos will be removed from the park next year, as part of the ongoing provincial and national strategy to increase the distribution of these species. In 2008, many of the large herbivore species had reached 10- year-high figures, but most have now dropped to lower levels. We are not sure exactly what has caused this decrease. It may have to do with natural downward fluctuations caused by a prolonged period of below average annual rainfall or incorrect fire burning practices. Or perhaps the herbivore decreases are a result of high numbers of predators, such as wild dogs and lions. To investigate the true cause of these decreases, we ve initiated various research projects that focus on lion, wild dog, cheetah, and leopard movement, demographics and prey selection. An additional monitoring project that we have initiated is a biannual road-based survey of herbivore demographics in order to determine recruitment of young into the herbivore population and whether any of the species display a skewed sex ratio. Hopefully these projects, in conjunction with the other ongoing monitoring in the park, will assist in determining why many of the herbivore species are in decline. On a positive note, the rate of decrease of some of the species, such as impala, nyala, warthog and waterbuck seem to have slowed, while white rhino numbers have continued to slowly increase (despite the poaching threat that these animals face in South Africa at the moment). The data that you, and previous volunteers, collected will also continue to be used in various external research projects and scientific papers which are planned for the next few years! Thanks again to all for your assistance with this project, the results of which are used directly by the management team as well as other researchers. Thanks also for entering the data immediately after you had completed the transects. It made Geoff's job of analysing the data very easy after you had left. The entire job was done successfully and extremely well! Regards, Dave 2

3 TOP HIGHLIGHT FROM THE PAST SEASON Population estimates for red (Cephalophus natalensis) and grey (Sylvicapra grimmia) duiker could be derived from this fielding season. The 2012 fielding season was the first time there were enough sightings of these species to determine population estimates, and although less transects were completed in the 2014 season (as a result of less volunteers), we were still able to determine estimates for these 2 species. Grey duiker: 532 (2012) and 785 (2014); Red duiker: 292 (2012) and 284 (2014). Section 1: Scientific Research Achievements REPORTING AGAINST RESEARCH OBJECTIVES Objective 1: Count the large herbivore component of game in Hluhluwe-iMfolozi Park (HiP). This was successfully achieved, despite the lower number of volunteers during this fielding season which resulted in less repetition of each of the transects. At least 60 sightings of each species are required for accurate estimates to be derived. This was possible for all species being counted with the exception of waterbuck (Kobus ellipsiprymnus; see note below). Photo courtesy of Earthwatch volunteer Jeff Wilson Objective 2: Use the data to determine a biennial estimate for the ungulate population of Hluhluwe-iMfolozi Park (HiP) which can be used to inform management decisions and highlight further research requirements. This was successfully achieved. The same methods have been used since 1996 which has produced reliable estimates and allowed scientific services to determine trends in the herbivore population numbers in the park. Over the past few years, there have been significant declines in many of the herbivores being counted [with the exception of buffalo (Syncerus caffer) and white rhino (Ceratotherium simum)] which has triggered numerous research projects and a review of the park s predator management plan. These research projects aim to determine the prey selection of wild dogs (Lycaon pictus) and lions (Panthera leo), to determine the population demographics (rather than just an estimate) of the herbivore population in various areas of the park, to determine whether there are top down or bottom up effects on the herbivores, and to determine what effect various parameters associated with wild dogs and lions have had on the herbivore population over the years. Because the game count data has been collected using the same methods since 1996 and there are other estimates prior to this, it is possible to look into these effects. 3 Photo courtesy of Earthwatch volunteer Jeff Wilson

4 Population trends of large herbivores in Hluhluwe-iMfolozi Park between based on surveys conducted by Earthwatch teams. White rhino counts are not included here due to recent increased threats from poaching. 4

5 Population trends- continued. 5

6 Note: With only 26 sightings, a statistically sound estimate for waterbuck cannot be derived, but with such low encounter rates, it is clear there are very few animals left in this population. There appears to be some stability since 2008 but there numbers are still a fraction of what they were 14 years ago. Objective 3: Use the data to establish long term trends in herbivore populations and ensure this data is accessible to research projects. As mentioned above, various research projects have been initiated which are using the data collected over the years by the Earthwatch-supported game census program. In addition, a book on the history of research and management in Hluhluwe-iMfolozi Park is in the final stages of completion before submission to the publishers (all chapters are completed and have been peer reviewed) and one of the chapters deals specifically with the trends in herbivore numbers and densities over the years. Section 2: Impacts 1. INCREASING SCIENTIFIC KNOWLEDGE MOS 1.1 Total Volunteer Research Hours - 2,175 hours of active data collection and entry MoS 1.2 Peer Reviewed Publications Van der Plas F, Howison RA, Mpanza N, Cromsigt JPGM and Olff H Different-sized grazers have distinctive effects on plant functional composition of the African savannah. Journal of Ecology. Vol. 104: Book chapter in preparation: Elizabeth le Roux, Geoff Clinning, Dave J. Druce, Norman Owen-Smith & Joris Cromsigt. Chapter 2. Temporal changes in the large herbivore fauna of Hluhluwe-iMfolozi Park. In Savanna Ecology and Management. Lessons in Conserving Biodiversity from Hluhluwe-iMfolozi Park. Edited by Joris Cromsigt, Sally Archibald & Norman Owen-Smith. Wayne Linklater & Adrian Shrader. Chapter 11. Rhino challenges: spatial and social ecology for habitat and population management. In Savanna Ecology and Management. Lessons in Conserving Biodiversity from HluhluweiMfolozi Park. Edited by Joris Cromsigt, Sally Archibald & Norman Owen-Smith. 6

7 Journal articles in preparation: Adrian M. Shrader, Norman Owen-Smith, Dave J. Druce & Geoff Clinning. Using natural dispersal processes to conserve and manage white rhinos within a closed system: a 25 year experiment. D.G. Marneweck, D.J. Druce, K.A. Marnewick & M.J. Somers, M.J. The effect of wild dogs, lions and rainfall on herbivores in Hluhluwe-iMfolozi Park, South Africa. MoS 1.3 Grey Literature and Other Dissemination of Your Results Marneweck, D.G., Druce, D.J., Marnewick, K. and Somers, M. J. The effect of wild dogs and rainfall on herbivores in Hluhluwe-iMfolozi Park, South Africa. Southern African Wildlife Management Association Annual Conference. Kimberley, 6-10 September. ORAL PRESENTATION Marneweck, D.G., Druce, D.J., Marnewick, K.A. & Somers, M.J. The effect of wild dogs and rainfall on herbivores in Hluhluwe-iMfolozi Park, South Africa. Symposium of Contemporary Conservation Practice, Fern Hill, 2-6 November. ORAL PRESENTATION Veldhuis MP, Le Roux E, Cromsigt JPGM, Berg MP and Olff H. Deteminants of patchiness of woody vegetation in an African savannah. Chapter of PhD thesis, University of Groningen. Results of the 2014 game census were displayed on the notice boards in the two tourist camps in Hluhluwe-iMfolozi Park and were sent to the tour operators that work inside the park. An annual game census report was produced for the park management team outlining the methods of the census, the estimate of each species (including confidence limits) and showing the trends in estimates for every two years since These estimates were used to inform removals for the 2014/2015 and 2015/2016 financial years. A white rhino count report was produced for the park management team which included the white rhino population estimate as derived from the game count census. 2. DEVELOPING ENVIRONMENTAL LEADERS MoS 2.1 Education What groups and individuals have benefited from educational experiences as part of your project this year? Describe any activities, significant accomplishments, or endeavors and who benefited. Presentations to show the results of the census were given to guides who work in the park, Honorary Rangers and to representatives of the Land Claimant group of people who own land included within the park s boundaries. In addition, various students were able to assist with the transects last year and gained invaluable experience in the field, learnt new data collection methods and interacted with the volunteers. All of them were thankful for the experience and developed immensely as a result of the experiences. 7

8 3. PARTERNSHIPS MoS 3.1 Organizations Actively Engaged There are a few NGO s whom we partner with to ensure the success of the park s management of the carnivore population. These include The Endangered Wildlife Trust and Wildlife ACT Fund in monitoring and managing the wild dog and cheetah population and with Panthera and Wildlife ACT Team in monitoring the trends in the leopard population in the park. Results of these censuses are integrated with the results of the game census supported by Earthwatch in order to best manage the park s wildlife. 4. CONTRIBUTIONS TO POLICIES OR MANAGEMENT PLANS MoS 4.1 Informing Policies or Management Plans Local Policies or Management Plans: Hluhluwe-iMfolozi Park Predator Management Plan this plan is currently under revision and was initiated because of the observed decline in the herbivore numbers which was observed by analyzing the biennial data collected during the game count census supported by Earthwatch. HiP is a vitally important contributor to the South African national wild dog and cheetah (Acinonyx jubatus) metapopulations and contains a significant proportion of the country s wild lion population (3rd most important after Kruger National Park and the Kgalagadi Transfrontier Park. Hluhluwe-iMfolozi Park Species Management Plan for White Rhino this plan was reviewed and updated in 2014 and guides the management of the second largest white rhino population in Africa (after Kruger National Park). The 2014 plan showed the results of the last 14 years of white rhino estimates (derived from the data collected by the Earthwatch volunteers) and stated that the game count transect methods had been used since 1996 to count white rhino in the park. The plan stated that these methods would continue for the 5 year validity period of the new plan. MoS 4.2 Actions or activities that enhance natural and/or social capital The cut game count transects were sampled after the game census for the distribution of alien plants. This will be an ongoing activity for the foreseeable future and will serve as one indication of the success of the alien plant clearing operations within the park. 5. ENHANCING NATURAL AND SOCIO-CULTURAL CAPITAL MoS 5.1 Conservation of Taxa Ceratotherium simum. White rhinoceros Megaherbivore which is considered to be a landscape engineer through their ability to create and maintain grazing lawns which support a different guild of grasses, insects and birds. Population size increased and improving population structure. 8

9 MoS 5.3 Conservation of Ecosystem Services There are a large number of ecosystem services that are maintained as a result of the Hluhluwe-iMfolozi Park. In order to ensure the park maintains and/or enhances all of the possible ecosystem services, it needs to be managed well. This includes ensuring the correct fire regime and a balance between the predators and herbivores in the park. The game census program provides almost all the data required on the trends in the herbivore numbers which can then be compared to rainfall, fire regimes and the distribution and abundance of predators. A detailed ecosystem service assessment was undertaken in the park approximately 5 years ago which showed that the park was very important in contributing the many different ecosystem service functions within the local area. MoS 5.5 Impacting Local Livelihoods Local employment is provided for about a 6 week period for approximately 60 people who are involved in cutting the transects prior to the arrival of the volunteers. During the time the volunteers are at the project, an additional 4 people are employed from the surrounding communities to cook and clean the two camps. Section 3: Acknowledgements, Funding and Appendices Project funding Additional funding is provided by Ezemvelo KZN Wildlife in the form of salaries of long term staff who are dedicated to the project for the 3 months that it is in progress. These include field rangers and Scientific Services staff. Ezemvelo also provides the vehicles and approximately 10 to 20% of the running costs of the vehicles. Besides this, all the resources required to undertake the monitoring project are provided by Earthwatch. Photo courtesy of Earthwatch volunteer Jeff Wilson 9