bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of dam construction on two elephant populations in northern Cameroon
Authors: De Iongh, , Tchamba Martin , Aarhaug Per , Verhage Bas
Published: November 2024

Construction of dams in northern Cameroon, the Maga Dam in the vicinity of Waza NP in 1979 and the Ladgo Dam in the vicinity of Bouba-Ndjidda, Benoue and Faro NPs in 1980 had profound effects on elephant populations in the northern Cameroon. The elephant populations in both areas increased rather dramatically and increased crop raiding has been a pattern in both areas. This article reviews data from 1994-2002 studies, focused on seasonal movement of the elephants and crop raiding problems. In 1978 the dry season elephant population in Waza NP was estimated at 465 animals, in 2001 the estimation was 1140. In the Lagdo area there were no elephants resident during the dry season prior to construction of the dam - twenty years later, in 2000 about 250-300 animals are in the area. The Waza elephant have undergone more scrutiny as they have been studied since 1986, but the Ladgo population has been observed only since 1995. 3 adults in each area (3 cows in Waza 1993,1994 and 1996: 1bull and 2 cows in Ladgo 2000) were radio collared in order to study movement, home range and habitat use by the subpopulations. Data suggest the home range of the Waza populations to be about 2546 sq kms while that of those in the Ladgo area is significantly less, about 119 sq kms. Dam construction in in the Waza area resulted in severe deterioration of the perennial floodplain vegetation between 1980-1994, and the Waza elephants showed seasonal migration to an area over 100 km south of the Park where they caused significant crop damage. After the floodplain was artificially reflooded in 1994 they did not alter this pattern of movement, but shifted their dry season habitat in the park from the Acacia savannah zone to the floodplain. The Ladgo elephant have consistently spend more time in the floodplain area, as their habitat did not deteriorate after the dam was constructed. (Saleh, et al., 2002. de Iongh, et al, 1999). This article was given aa a paper 'Impact of dam construction on two elephant populations in Northern Cameroon' at the 6th AfESG meeting at Mokuti Lodge, Namibia, 4-8 December 2003.
Clarifying MIKE and ETIS
Authors: Hunter Nigel , Milliken Tom
Published: November 2024

This article is a rebuttal to Reeves, et al. which was written as an opinion article in Pachyderm 35. (Reeves, et al. 2003) The authors note that it was the Conference of the Parties at CoP10 which set out the conditions regarding one-off sales of ivory and that the Standing Committee had no power to alter such decisions. They state 'The decision to develop a monitoring system to track illegal killing of elephants in the field was intitated by the African range states and agreed by CITES Parties at CoP10 in Resolution Conf.10.10'. The authors, who are both directly involved in the development and operative aspects of MIKE and ETIS, use this article to review their implementation. 'MIKE uses a statistical approach to look at relationships between the illegal killing of elephants and various possible explantory features', while 'ETIS is a comprehensive information system to track illegal trade in ivory and other elephant products. ' The authors suggest that Reeves et al., should have allowed for greater differentiation between criticism of MIKE and ETIS and that ETIS was functioning sufficiently well by CoP12 to allow for the decision for the one-off sales, but they do acknowledge that more time is needed for MIKE to be fully operational.
African Elephant Specialist Group/Group des Specialistes des Éléphants d'Afrique
Authors: Dublin Holly
Published: November 2024

Notes recent major meetings/conferences associated with or focused on African elephants, and reviews the ongoing work towards the next update of the next African Elephant Status report (formerly AED), on going work regarding implementation of an elephant conservation strategy for the SADC countries, ongoing field and assessment work concerned with Human Elephant Conflict, an update on the MIKE programme and some of the reseacch carried out under the Small Grants Programme. This latter AfESG programme undertaken with funds provided by the Europeon Community implemented 22 projects in 13 range states between 2002 and November 2004.
The concept of home range in relation to elephants in Africa
Authors: Osborn Ferrel
Published: November 2024

The article outlines the concept of home range, compares different methods that have been used to determine ranges and discusses their relevance to elephant ecology. After reviewing earlier works on the concept the author focuses on core areas and reviews four methods of assessing the structure of core areas: minimum convex polygon, harmonic mean, cluster and kernel. 'Rainfall is used as a variable across elephant habitats to explain range variation' and the author uses Table 2 to illustrate a comparison of the size of the range, the number of elephants (in the study area), and the rainfall in mm in various ecosystems across the continent. He notes that humans have impacted on the pattern of elephant range and that elephants wherever possible tend to avoid areas of illegal hunting and human settlements. Concludes it is important to understand core areas and to link their relevance to elephant conservation, and to appreciate that rainfall is basic to the difference in range size, but that human activity is playing and ever increasingly important role.
The elephants (Loxodonta africana) of Zoba Gash Barka, Eritrea: Part 3. Ecological and other data from tusks, teeth and carcasses
Authors: Yacob Yohannes , Shoshani Jeheskel , Hagos Yohannes , Kebrom Emun
Published: November 2024

An isolated elephant population of about 100 animals live in the border region of northwestern Ethiopia and southwestern Eritrea. During the October-February dry season these elephant migrate to Eritrea and return southward to Ethiopia at the beginning of the short wet season. (Hagos, et al. 2003: Shoshani, et al. 2004) During dry period the only natural occuring permanent open water may be the Setit (Tekezze) River which forms the border between the two countiries. This article, the third of a series, 'summarizes nine years of ecological data retrieved from tusks and three years of data from dead elephants'. Body measurements and pathological data were taken from 11 elephants which were found dead between 2002 and 2004: four had fallen into manmade water wells, two were killed by farmers, and 'five died form unknown causes although some exhibited pathological bones and teeth.' Table 1 reviews information on the recently dead elephants while Table 2 reviews data (lengths, circumferences, weight, etc) from the 31 tusks collected since 1993. The authors note their observations confirm that a healthy elephant population inhabits the southwestern region of Eritrea duirng the long dry season. However, over the past three years it has suffered a loss of about 5% per annum, and this loss is in part due to attempts to drink from manmade wells because of the lack of natural water sources. Recommends artificial water sites, constructed so that young elephants could access them easily, be installed 'along the path of elephant movement. Calls for the establishment of protected areas because as this population increases the conflict with the human populations will become greater and more contentious land use issues will arise.
Nature and extent of human-elephant conflict in Bia Conservation Area, Ghana
Authors: Kofi Sam, , Danquah Emmanuel , Oppong Samuel , Ashie Enoch
Published: November 2024

During the 2004 rainy season the nature and extent of human-elephant conflict focused on crop raiding and damage was investigated in and around Bia Conservation Area (comprised of two forest areas Bia NP and Bia Resource Reserve to the south of the Park). 49 elephant crop raiding incidents involving 44 farms belonging to 36 farmers from 18 villages were recorded during the study period. Questionnaire based interviews were undertaken with 42 randomly selected members of 11 randomly selected fringe communities of the 20 major communities witin 7 kms of the Conservation Area boundary. Information on the current crop damage was collected within 48 hours of the incident: field location, size, crop type and growth stage, extent of damage were recorded. Severe crop damage starts in June and increases until peaking in September/October and then declines until becoming minimal in December. The majority of interviewees (72%) were new immigants to the area, and had no idea about the relative number of elephants in the area. Over 90% employed some kind of traditional deterrent for driving the elephants away. Based on visual and track identification it appeared that at least 24 male and 12 female elephant were involved in the raiding incidents. In term of age 43 adults and 33 subadults and infants were seen on different occasions. Elephant crop raiding dates to the 1970s when immigrants came to the area and began farming in close proximity to the reserves. It has increased, now family groups as well as bulls raid, raiding occurs anytime of the day and throughout the year, although it is most prevalent in the wet season here as it is in Kakum CA. Farmers should be encouraged to protect their crops. However, elephants habituate to many scare techniques, farmers must constantly assess the risk involved including planting fields far from areas frequented by migrating elephant.
Population survey of elephants in Okwangwo Division, Cross River National Park, Nigeria
Authors: Obot Emmanuel , Edet Clement , Ogar Gabriel , Ayuk Joy
Published: November 2024

A elephant census based on dung counts along five trails, with a total length of 139 kms, was undertaken March 1997-May 1998 in Cross River NP, Nigeria. 'There appears to be a seasonal local migration of this population between Cross River NP and the neighbouring Takamanda FR in Cameroon: the elephants spend most of the rainy season in Cameroon and the dry season in Cross river NP.' Within the park elephants seem to occupy a home range of about 239 sq km, from Okwangwo in the centre of the park through Bamba on the eastern boundary to Bashu on the south, and dung count analysis suggests 74 animals in this area. This study indicates 50 to 130 elephant are in the area, and interviews with hunters suggest there are about 10 groups of around 15 animals per group. This latter figure suggests 150 animals in total which compares favourably with the study maximum estimate of 130. Authors note poaching for ivory and meat was excessive before the park was gazetted in 1991, and antipoaching activities must be maintained if any population is to survive.
Analyse biometrie des pointes d'elephants saisies dans le cadre de lutte antibraconnage par les services de la conservation dans le massif du Sud-est Cameroun
Authors: Noupa Paul
Published: November 2024

This article assesses data from tusks measured during a study focusing on biometric measurements taken on the carcasses of forest elephant poached in southeastern Cameroon. Measurements from 62 tusks suggest that 2 out of 3 elephants poached in this region are young individuals. 'The average tusk weight of the poached elephants examined was 4.44 kg, against an average of 15 kg estimated for the area. Data provides an indicator of the type of offtake in the area and its potential impact on the population as a whole. This analysis 'provides evidence that sexual diamorphism becomes apparent in young elephants when the tusk length reaches 75 cm. The author notes that although the sample was small, the study provided an initial data set for detailed knowledge on the population structure of southeastern Cameroon's elephant populations, and he hopes that professional hunting guides will take measurements to supplement it
Can African elephants survive and thrive in monostands of Colophospermum mpane woodlands?
Authors: Lagendijk D. , De Boer, , Van Wieren,
Published: November 2024

This literature review based paper focused on the food value/energy requirements of Colophospermum mopane to elephants. Mopane is an important browse for elephant in southern Africa and is particularly heavily utilized during the dry season because it is 'one of the few food plants still carrying leaves during this bottleneck period'. Mopane leaves collected in May from Kruger NP and data from mopane in the Tuli area of Botswana during all season were used in the calculations for daily food intake and gross energy requirements. (Owen-Smith 1988: Styles and Skinner 1997, 2000) Elephant spend 12-18 hours of the day foraging . 4% of their live weight is considered to be the daily browse intake. This study found that the animals required more mopane browse than 4% of their live weight and so in as long as they can browse for the length of time required to provide for the greater intake they could survive. Calculations suggest a mature bull browsing solely on mature green mopane would need to browse for 14 hours in order to achieve energy requirements. The nutritive quality of mopane is high throughout the year, this study suggests its energy content is sufficient for elephants year round if they utilize all parts (leaves, twigs, bark) and given they have sufficient browse time to take in larger quanitities in times of lower nutrition value. Mopane are known to be high in tannins, and research is needed to understand the effects these and other secondary compounds have on intake,digestibility and metabolism.
Elephant numbers in Kafue National Park, Zambia
Authors: Guldemond Robert , Lehman Emily , Ferreira Sam , Van Aarde,
Published: November 2024

This article compares aerial survey data from the Kafue NP and surrounding GMAs from 1991 to 2004. This was done in part to check the precision of the counts and in part as a reviews the apparent situation in Zambia which suggests that unlike other southern Afican areas the elepahant population of Zambia is decreasing rather than increasing. The estimated population was over 10000 in 1991 with about half in Kafue NP itself and the rest largely in Mumbwa and Sichifula GMAs, with about 2500, and in Mulobezi with about 1600 and a some in Lunga-Luswich. In a 1996 survey the total population was under 5000 the majority of animals were in Kafue NP with a small number in Mumbwa and Sichifula GMAs. The 2004 survey noted elephant only in Kafue NP itself and the estimated total population was 1555 which was lower tht the 3798 estimation from the 2001 counts which also observed animals only in Kafue NP.
Northern Sudan ivory market flourishes
Authors: Martin Esmond
Published: November 2024

This article reviews a January-February 2005survey intended to assess the status of ivory markets in Omdurman and Khartoum. The author suggests 'ivory market in the Khartoum-Omdurman area of northrt sudan is one of the few in the world tht has expanded significantly since the mid-1990s'. He found the price craftsment paid for raw ivory had increased 'workhop owners and craftsmen pay USD 105/kg for a 2-5 kg tusk compared with USD 44/kg for a 5-10 kg tusk in 1997'. The number of craftsment has also increased during this same time period, about 150 craftsmen who carve both ivory and work were identified compared to about 100 in 1997. Jewellery and small figurines are the most common items made. The author noted 50 retail outlets who displayed over 11300 items made from tusks probably obtained from elephant poached since 1990. Accoding to Sudanese law this trade in new ivory is illegal ,and the author suggest that is 'threatening central African elephant populations'. The items are cheap compared with prices in other countires and nearly all the buyers are foreigners working in Sudan.
Elephant death, possibly by constipation
Authors: Vyas Dhaval , Goodwin Thomas , Rasmussen L. , Schulte Bruce
Published: November 2024

This article reviews the observations and analysis concerning the death of a wild juvenile male elephant which apparently died from constipation, probably from eating sisal, a plant rarely eaten by elephant. When the young animal was first seen in the vicinity of a waterhole on Ndarakwai Ranch in Tanzania on Decmber 21 2004 the researchers noted its rather odd behaviour. The juvenile was seen several times between that date and its death on Janury 3, 2005. Although at first it appeared to be part of a family unit the young male spent little time with other young elephants or specific adults. What appeared to be a protuding bolus was evident on the first day of observation. The young male spent a significant amount of time rubbing on trees and soaking in the mud, but was rarely seen drinking, eating or interacting with other its own age or younger. Examination of the carcass confirmed constipation probably caused by ingesting sisal. The faeces contained prickles and the undigested fibres of the sisal had formed long cables.
Status of elephant populations in Garamba National Park, Democratic Republic of Congo, late 2005
Authors: De Merode Emmanuel , Inogwabini Bila-Isia , Telo José , Panziama Ginengayo
Published: November 2024

An aerial reconnaissance of the southern sector of Garamba National Park was undertaken between 14 and 24 August 2005 at the request of the Institut Congolais pour la Conservation de la Nature. Almost all of the parkʼs wildlife is reported to be limited to the southern sector. In total, 32.4 hours of transects were flown between the Dungu and the Garamba Rivers (1610 km 2 ). A small proportion of the Gangala na Bodio Hunting Reserve was also covered (130 km 2 ). Atmospheric conditions were excellent, with stable air and clear visibility, but observations were hindered by long grass. A minimum estimate of 1202 elephants was made based on a total count of all individuals encountered. Twenty-eight elephant carcasses were sighted—1 was recent (< 1 month) with ivory removed and 27 were old (> 1 month)—and 13 poaching camps were seen.
A la demande de lʼInstitut Congolais pour la Conservation de la Nature, on a procédé à une reconnaissance aérienne du secteur sud du Parc National de la Garamba entre le 14 et le 24 août 2005. Les rapports indiquent en effet que presque toute la faune du parc se limite au seul secteur sud. Au total, on a volé pendant 32,4 heures en traçant des transects entre les rivières Dungu et Garamba (1610 km 2 ). On a aussi couvert une petite partie de la Réserve de chasse de Gangala na Bodio (130 km 2 ). Les conditions atmosphériques étaient excellentes, lʼair était stable et la visibilité parfaite mais les observations étaient compromises à cause des hautes herbes. On a pu faire une estimation minimum de 1202 éléphants en se basant sur le comptage total des animaux rencontrés. On a repéré 28 carcasses dʼéléphants, une était récente (moins dʼun mois) dont lʼivoire était enlevé, et 27 étaient plus anciennes (plus dʼun mois) et on a aussi vu 13 camps de braconniers.
Composition of intestinal ciliate fauna of free-ranging African elephants in Tsavo West National Park, Kenya
Authors: Obanda Vincent , Lekolool Isaac , Kariuki John , Gakuya Francis
Published: November 2024

This study aimed at surveying intestinal protozoan ciliates of the African elephant (Loxodonta africana) in Tsavo West National Park, Kenya. Faecal samples of seven elephants chemically immobilized for translocation were collected opportunistically and flotation-sedimentation techniques used to assess the presence of ciliates. Identification of ciliates was based on morphological features such as shape, presence and morphology of external spines and lobes, micro- and macronuclei, and internal skeletal plates. Seven ciliate families and 27 genera were found in the faecal samples of the elephants. The families included Blepharocorythidae, Buetschliidae, Cycloposthiidae, Isotrichidae, Ophryoscoleciidae, Paraisotrichidae and Troglodytellidae. The dominant families were Buetschliidae with nine ciliate genera and Cycloposthiidae with eight. These ciliates in the caecum and colon of elephants are similar to those in the rumen and reticulum of ruminants. They digest plant fibres (principally cellulose and hemicellulose) that otherwise could not be used since elephants have no fibre-digesting enzymes of their own. This preliminary information will guide comparative studies on the rumen ciliate diversity and population of various hosts in different regions.
Cette étude voulait analyser les protozoaires ciliés présents dans lʼintestin des éléphants africains (Loxodonta africana) du Parc national de Tsavo-ouest, au Kenya. On a profité de lʼimmobilisation chimique de sept éléphants qui devaient être déplacés pour récolter des échantillons de crottes et lʼon a utilisé des techniques de flottaison-sédimentation pour évaluer la présence de ciliés. Lʼidentification des ciliés sʼest faite sur la base de caractéristiques morphologiques telles que la forme, la présence et la morphologie de crêtes ou de lobes externes, de micro- et macronucléus, et de plaques squelettiques internes. Sept familles de ciliés et 27 genres furent découverts dans les échantillons fécaux des éléphants. Les familles incluent les Blepharocorythidae, les Buetschliidae, les Cycloposthiidae, les Isotrichidae, les Ophryoscoleciidae, les Paraisotrichidae et les Troglodytellidae. Les familles dominantes étaient les Buetschliidae, avec neuf genres de ciliés et les Cycloposthiidae, avec huit. Ces ciliés présents dans le caecum et le colon des éléphants sont semblables à ceux que lʼon trouve dans le rumen et lʼergastoplasme des ruminants. Ils digèrent les fibres végétales (principalement la cellulose et lʼhémicellulose) qui, sans cela, ne pourraient pas être utilisées puisque les éléphants ne produisent pas dʼenzymes leur permettant de digérer les fibres par eux-mêmes. Cette information préliminaire pourra servir de guide pour des études comparatives de la diversité et les populations des ciliés du rumen de divers hôtes dans différentes régions.
Application of ArcView Animal Movement Analysis Extension as a tool for monitoring elephant movement: preliminary results from northern Cameroon
Authors: Foguekem Désiré , Tchamba Martin , Macallister Mark , Ngassam Pierre , Loomis Mike
Published: November 2024

ArcView Animal Movement Analysis Extension was used to survey the movement of two female elephants, Eka from Benoué National Park and Habsatu from Bouba Ndjida National Park in northern Cameroon. The results show that Eka is seldom in the park if 5% of the outliers are not considered, while Habsatu is in the park more often, especially in its northern and western parts, and she moves over the border into Chad. Home ranges were calculated as 1750 km 2 for Eka and 2058 km2 for Habsatu. Recommendations are made for improving the study in the future.
L’Extension ArcView Analyse du Mouvement Animal a été utilisé pour étudier le mouvement de deux éléphants femelles, Eka et Habsatu respectivement des parcs nationaux de la Bénoué et de Bouba Ndjida au nord Cameroun. Les résultats montrent que, Eka est difficilement dans le parc lorsque 5 % des points externes sont retirés alors que Habsatu est très souvent dans le parc et plus précisément dans les portions nord et ouest du parc, et se déplace vers la frontière à l’intérieur du Tchad. Les domaines vitaux étaient calculés comme étant de 1750 km2 pour Eka et de 2058 km 2 pour Habsatu. La discussion est donnée suivi des recommandations pour améliorer l’étude dans le future.
Forest elephant dung decay in Ndoki Forest, northern Congo
Authors: Breuer Thomas , Hockemba Mireille
Published: November 2024

The decay of elephant dung piles has been shown to be a complex process. Rainfall has been attributed as the main factor influencing dung pile survival in various central African forests. This study monitored elephant dung piles from deposition to disappearance to show that dung survival in Ndoki Forest in northern Congo is mainly influenced by the intensity of irradiance and minimum temperature in the days after deposition. This could lead to substantial differences of dung decay in pristine forest compared with logged forest with a disturbed canopy, and care should be taken when applying rainfall models to calculate dung decay rates. On-site surveying of elephant dung piles covering all habitat types should therefore be undertaken before any elephant dung survey is conducted.
Additional key words: density estimates, Loxodonta africana cyclotis, monitoring, rainfall, rainforest
Il a été démontré que la dégradation des crottes d’éléphants est un processus complexe. On a montré que dans les forêts d’Afrique Centrale, la quantité de pluie tombée est le facteur principal qui influence la durée de visibilité des crottes d’éléphants. Dans cette étude nous avions suivi la dégradation des crottes du jour de leur déposition jusqu’à leur disparition afin de montrer que dans la forêt de Ndoki située au Nord Congo, la dégradation est principalement influencée par l’intensité de solaire et la température minimale dans les jours qui suivaient leur déposition. Ce qui pourrait conduire à des différences appréciables vis-à-vis la dégradation des crottes dans les forêts intactes et les forêts perturbées. Par conséquent, il faut faire attention en appliquant les modèles de la pluie (« rainfall models »). Avant chaque inventaire sur la densité des éléphants, il est recommandé d’étudier la dégradation des crottes dans le site d’étude.
Mots clés supplémentaires : estimations de densité, Loxodonta africana cyclotis, monitoring, pluie, forêt dense
Increased demand for rhino horn in Yemen threatens eastern Africa’s rhinos
Authors: Vigne Lucy , Martin Esmond , Okita-Ouma Benson
Published: November 2024

Conservation organizations have neglected Yemen’s role in the rhino horn trade since early 2003, with no attention given to the problem, although most horns from eastern Africa’s poached rhinos are known to go there. Therefore, in early 2007 we collated data on rhino poaching in eastern Africa, and the first two authors carried out a survey in Yemen to update information on rhino horn smuggling. We learned that demand has risen substantially with the price of rhino horn up by 40% in four years, despite an increase in quantity of horns entering the country. We had meetings with decisionmakers to try to curtail the trade and improve public awareness to reduce demand for rhino horn.
Les organisations de conservation ont négligé le rôle que le Yémen tient dans le commerce de corne de rhino depuis le début de 2003 et elles n’accordent pas d’attention à ce problème alors qu’on sait que la plupart des cornes des rhinos braconnés en Afrique de l’Est vont là-bas. C’est pourquoi, début 2007, nous avons rassemblé toutes les données sur le braconnage de rhinos en Afrique de l’Est, et les deux premiers auteurs ont mené une enquête au Yémen pour actualiser les informations sur la contrebande de cornes de rhinos. Nous avons appris que la demande s’était considérablement accrue et que le prix de la corne avait augmenté de 40 % en quatre ans, malgré une augmentation de la quantité de cornes arrivant dans le pays. Nous avons rencontré des décideurs pour tenter de réduire le commerce et de sensibiliser le public afin de diminuer la demande de corne de rhino.
Comparison of two dung count methods for estimating elephant numbers at Kakum Conservation Area in southern Ghana
Authors: Boafo Yaw , Manford Mildred , Barnes Richard , Hema Emmanuel , Danquah Emmanuel , Awo Nandjui , Dubiure Umaru-Farouk
Published: November 2024

The efficiency of meandering transects—in terms of accuracy, precision and effort required for estimating elephant abundance—was evaluated in the Kakum Conservation Area in Ghana. Four consecutive elephant dung surveys were carried out between February 2000 and February 2002 using meandering transects. The resulting dung density estimates were adjusted by applying a correction factor calculated from matched pairs of meandering transects and standard line transects. The meandering transects required less effort and took 40% less time than line transects and were preferred by the park’s staff, but these gains must be balanced against the loss in precision. Elephant densities were estimated from the dung densities with a rainfall model. Empirical and analytical methods were compared for estimating the precision of the elephant estimate. The analytical method returned a more precise estimate for the merged estimate, which was 161 elephants (95% CI from 104 to 249). A genetic survey of the same population by Eggert et al. (2003) using the accumulation method gave a similar estimate of 170 elephants (95% CI from 96 to 270).
L’efficacité des transects en serpentin a été évaluée dans la Région de Conservation de Kakum au Ghana pour estimer l’abondance des éléphants en termes d’exactitude, de précision et de l’effort exigé. Quatre études consécutives d’excréments des éléphants ont été réalisées entre février 2000 et février 2002 en utilisant le transect en serpentin. Les estimations résultant de la densité des excréments ont été ajustées en appliquant un facteur de correction calculé à partir des paires de transects en serpentin et des transects linéaires standards. Les transects en serpentin exigeaient moins d’effort et prenaient 40% moins de temps que les transects linéaires et le personnel du parc les préféraient, mais ces gains doivent être équilibrés contre la perte en la précision. On a estimé les densités des éléphants par le biais des densités des excréments avec un modèle des pluies. Les méthodes empiriques et les méthodes analytiques ont été comparées pour estimer la précision de l’estimation des éléphants. La méthode analytique a donné une estimation plus précise pour l’estimation fusionnée qui était de 161 éléphants (95% CI de 104 à 249). Une étude génétique de la même population par Eggert et al. (2003) en utilisant la méthode d’accumulation a donné une estimation semblable de 170 éléphants (95% CI de 96 à 270).
État des maraudes et des dégâts de cultures liés aux éléphants à l’ouest du secteur de Djouroutou dans le sud-ouest du Parc National de Taï (Côte d’Ivoire)
Authors: Ouattara F.A. , Soulemanee O. , Nandjui A. , Tondoh E.J.
Published: November 2024

Cette étude menée de septembre à novembre 2007 a pour objectif d’évaluer les dégâts de cultures par les éléphants afin d’atténuer ou de prévenir les conflits homme-éléphant dans une perspective de réduction de la pauvreté des populations rurales et de sauvegarde des populations résiduelles d’éléphants. L’utilisation d’un questionnaire a permis de collecter les avis des producteurs. Deux (2) placeaux (2000m x 500m) ont été installés dans la périphérie du Parc National de Taï (PNT) pour suivre et estimer les dégâts des éléphants. Le dénombrement des tas de crottes s’est déroulé sur 10 layons longs de 5 km chacun. La densité des tas de crottes a été estimée par le programme DISTANCE 4.1. Aucun dégât n’a été observé durant la période d’étude. Cependant, les enquêtes ont révélé leur importance entre 2002 et 2005 avec des proportions variant de 4 à 33,3%. Au total, 12 chefs d’exploitation sur 42 ont été victimes de dégâts de cultures causés par les éléphants et les pertes moyennes atteignent 13,7% de leur production agricole. La proportion de plaintes des paysans enregistrées est faible (16,7%) et les méthodes de dissuasion pratiquées sont différentes d’un producteur à l’autre. La densité d’éléphant estimée dans la partie du Parc adjacente aux cultures, est de 1,1 ± 0,7 éléphants. km-2 .
Mots clés : Conflit homme-éléphant, Dégâts de culture, Densité de tas de crottes, Eléphant de forêt, Parc National de Taï, Secteur de Djouroutou
The aim of this study carried out in September to November 2007 was to assess crop damage by elephants in order to mitigate human-elephant conflict with an aim of reducing poverty among rural people and saving the residual elephant population. A questionnaire was used to collect farmers’ opinions. Two plots (2000m x 500m) at the periphery of the National Park of Taï were used to monitor and estimate elephant damage. Elephant dung piles were counted on 10 line transects of 5 km each. Dung density was estimated using the DISTANCE 4.1 program. No damage was observed during the study period. However, damage had been significant between 2002 and 2005 and varied from 4% to 33.3%. In total, 12 out of 42 farmers have suffered from damage caused by elephants. The average crop lost was 13.7%. A lower proportion (16.7%) of farmers recorded complaints with deterrent methods differing from one farmer to another. Elephant density was estimated to be 1.1 ± 0.7 elephants per km-2 in the sector of the Park bordering the crops.
Keywords: Human-elephant conflict, crop damage, dung pile density, forest elephant, Taï National Park, Djouroutou sector
Black rhino conservation in Tanzania: translocation efforts and further challenges
Authors: Fyumagwa Robert , Nyahongo Julius
Published: November 2024

Tanzania had many black rhinos (Diceros bicornis) in the 1960s but was hit by ruthless poaching between the 1970s and late 1980s. From the 1990s, the country declared a war against unscrupulous poachers in order to conserve the few remaining rhinos. The current strategy is to reintroduce black rhinos that were originally from East Africa in order to increase genetic diversity. Three translocations of black rhinos between 1997 and 2001 involved 10 animals from South Africa, two of which were reintroduced to Ngorongoro Crater and eight to Mkomazi National Park. In 2007, two black rhinos from Port Lympne Wild Animal Park, UK, were introduced into a sanctuary adjacent to Ikorongo-Grumeti Game Reserves. In June 2009, three black rhinos from the Czech Republic were translocated to Mkomazi National Park. Another translocation operation is expected to begin in May 2010 whereby 32 black rhinos will be translocated into the Serengeti ecosystem from Thaba Tholo, Thabazimbi, South Africa. Although the first five translocation operations went well, the challenge is the management of the reintroduced rhinos amid the growing social-ecological pressures affecting protected areas. Management authorities should consider the recommended sex ratio for rhino populations to avoid excessive male aggression.
Keywords: Black rhinos, conservation, poaching, translocation
La Tanzanie avait beaucoup de rhinocéros noirs (Diceros bicornis) dans les années 1960 mais elle a été touchée par un braconnage impitoyable entre les années 1970 et la fin des années 1980. Depuis les années 1990, le pays fait la guerre contre les braconniers sans scrupules en vue de conserver les quelques rhinocéros qui restent. La stratégie actuelle est de réintroduire des rhinocéros noirs qui étaient originairement d’Afrique de l’Est pour amplifier la diversité génétique. Trois translocations de rhinocéros noirs entre 1997 et 2001 concernaient 10 animaux provenant d’Afrique du Sud, deux d’entre eux ont été réintroduits dans le Parc national du cratère de Ngorongoro et huit dans le Parc national de Mkomazi. En 2007, deux rhinocéros noirs provenant du Parc de la faune de Port Lympne, au Royaume-Uni ont été introduits dans le sanctuaire adjacent de la Réserve naturelle d’Ikorongo-Grumeti. En juin 2009, trois rhinocéros noirs provenant de la République tchèque ont été transférés au Parc national Mkomazi. Une autre opération de translocation par laquelle 32 rhinocéros noirs seront transférés dans l’écosystème Serengeti à partir de Thaba Tholo, Thabazimbi en Afrique du Sud est prévue de commencer en mai 2010. Bien que les cinq premières opérations de translocation se soient bien passées, le défi reste de savoir comment gérer des rhinocéros réintroduits au milieu de pressions socio-écologiques croissantes qui affectent les aires protégées. Les autorités de gestion devraient examiner la sex-ratio recommandée pour les populations de rhinocéros pour éviter une agression mâle excessive.
Camera trapping as a method for monitoring rhino populations within the Waterberg Plateau Park, Namibia
Authors: Stein A. , Erckie B. , Fuller T. , Marker L.
Published: November 2024

For species with unique markings, camera trapping has been used as a non-invasive method for generating population estimates and monitoring the fate of particular individuals. Rhinos—both black (Diceros bicornis) and white (Ceratotherium simum)—have unique horn sizes, shapes and scarring, making camera trapping a monitoring technique that could be useful. Over a 7-week period during 2006 in the Waterberg Plateau Park (WPP) in Namibia, we obtained 125 photos of rhinos from 11 camera stations during 545 camera nights, about half of which were useful in identifying 18 individual black rhinos and 13 white rhinos. Additional coverage of the Park could lead to more complete counts that would complement ongoing monitoring efforts.
Key words: camera trapping, monitoring, black rhino, white rhino, Namibia
Pour des espèces ayant des marques uniques, le piégeage photographique a été utilisé comme une méthode non envahissante pour produire des évaluations des populations et surveiller la situation des individus particuliers. Les rhinocéros noirs (Diceros bicornis) et blancs (Ceratotherium simum) ont la taille des cornes, des formes et des marques uniques, rendant le piégeage photographique une technique de surveillance qui pourrait être utile. En 2006, sur une période de sept semaines nous avons obtenu 125 photos de rhinocéros de 11 stations photographiques pendant 545 nuits de photographie au Parc du plateau de Waterberg en Namibie, dont environ la moitié servait à identifier 18 différents rhinocéros noirs et 13 rhinocéros blancs. Une couverture supplémentaire du parc pourrait mener à des comptages plus complets qui compléteraient les efforts de surveillance en cours.
Why do elephants destroy woodland? [Commentt 2] [letter to the editor]
Authors: Olivier Robert
Published: November 2024

Refers to the article by Jachmann and Bell in the previous issue, no 3 p9-10, and notes because of both nutritional needs and the fact that elephants are a ecotone species between forest and grasslands they are both browsers and grazers. Suggests changes are part of ecology and as such an long term equilibria between elephants and woodland is not a feasible concept.
Optimizing the habitat of the Javan rhinoceros (Rhinoceros sondaicus) in Ujung Kulon National Park by reducing the invasive palm Arenga obtusifolia
Authors: Hariyadi Adhi , Priambudi Agus , Setiawan Ridwan , Daryan  , Purnama Hendra , Yayus Asep
Published: November 2024

The dominance of the arenga palm had been identified as a potential limiting factor in the distribution of Javan rhinos because it prevented the growth of food plant species, thus created a nutrition-poor area in which rhinos roamed. Palm dominance was reduced in an area consisting of four 1-ha plots (assigned as plots A–D) that was selected on the basis of various ecological criteria such as number of palm trees (shading) and potential for connecting home ranges of several rhinos. The research was carried in two phases—palm control and monitoring—to study the impact of palm control on the growth of food plants and, consequently, on the area’s accessibility by rhinos. Palm control resulted in increasing abundance and diversity of food plants for rhinos, and increasing visitation by rhinos. Results from this research show that controlling palm and other invasive plant species can potentially be used to improve the Javan rhinoceros’s accessibility to certain areas within the habitat.
La domination du palmier Arenga avait été identifié come un facteur limitatif potentiel dans la distribution des rhinocéros de Java, car il empêche la croissance des espèces de plantes alimentaires et crée une zone « pauvre en nurition » pour les rhinocéros. La réduction de la domination du palmier s’est effectuée dans une zone composée de quatre parcelles d’un ha sélectionées sur base de divers critères écologiques tels que le nombre de palmiers (ombrage) et le potentiel de relier les habitats vitaux de plusieurs rhinocéros. La recherche a été effectuée en deux phases—le contrôle de palmier Arenga a entraîné une augmentation de l’abondance et de la diversité des plantes alimentaires pour les rhinocéros ainsi qu’une augmentaiton de la fréquentation par les rhinocéros. Le résultat de cette recherche montre que le contrôle du palmier et des autres espèces de plantes envahissantes pourrait être utilisé pour améliorer l’accessibilité des rhinocéros à certaines zones au sein de leur habitat.
Dispersal and social behaviour of the three adult female white rhinos at Ziwa Rhino Sanctuary in the immediate period before, during and after calving
Authors: Patton Felix , Campbell Petra , Genade Angie , Ayiko Robert , Lutalo Godfrey
Published: November 2024

The paper presents details of the dispersal and social behaviour of the three adult female white rhinos at Ziwa Rhino Sanctuary in Uganda in the period one month before, the month during and one month after calving where published information from other reserves is limited. All six births occurred during night-time hours in areas of dense habitat. Births took place within 32 hours of the older calves being chased away by their mothers. Each female moved within the rhinos’ preferred habitat of open woodland with short grass and spent most of her time alone with her new calf and little time associating with other rhinos in the population. Apart from the chasing away of the older calves, there was no indicator of an impending birth.
Le document donne les détails de la dispersion et du comportement social des trois rhinocéros blancs femelles adultes au sanctuaire de Ziwa au cours du mois avant, pendant le mois et le mois après le vêlage là où les informations publiées à partir d’autres réserves sont limités. Les six naissances ont eu lieu durant la nuit dans des zone d’habitat dense. Les naissances ont eu lieu dans les 32 heures après que les jeunes rhinocéros plus âgés aient été chassés par leurs mères. Chaque femelle s’est déplacée vers l’habitat de rhinocéros préféré de fôrets claires aux herbes courtes où elle a passé la plupart de son temps seule avec son nouveau bébé en s’associant peu avec d’autres rhinocéros dans la population. En dehors du fait d’avoir chassé des jeunes rhinocéros plus âgés, il n’y avait aucun autre indicateur d’une naissance imminente.
Landscape-level assessment of the distribution of the Sumatran rhinoceros in Bukit Barisan Selatan National Park, Sumatra
Authors: Pusparini Wulan , Wibisono Hariyo
Published: November 2024

We conducted the first systematic survey on Sumatran rhinoceros following a robust patch occupancy framework in 3,500 km 2 of Bukit Barisan Selatan National Park (BBSNP), Sumatra, Indonesia. We surveyed 55 grids (72.25 km 2 ) between November 2007 and July 2008 to generate a reliable estimate of the proportion of area occupied (occupancy) by the Sumatran rhinoceros. Rhinoceros signs, e.g. footprints, dung, tree twists and wallows, were recorded along 833 km of transect routes, and 1-km sampling interval was used to develop detection/non-detection history for each grid. Rhinoceros signs were detected on 11 grids producing a naïve occupancy of 0.2. Occupancy modelling was used to control for imperfect detection probability (P). Based on the Royle/Nichols Heterogeneity model we concluded that Sumatran rhinoceros occupied approximately 32% of the BBSNP area (SE = 0.09). Occupancy can serve as a robust surrogate for an index of abundance in a population-monitoring framework. Further analysis using the multi-season models of the technique on time series data and season/survey-specific covariates can provide management authorities with accurate information about changes in rhinoceros populations and assist in prioritizing conservation actions for the Sumatran rhinoceros in the region.
Nous avons mené une première enquête systématique sur les rhinocéros de Sumatra en suivant un cadre robuste d’occupation du territoire sur une superficie de 3500 km 2 du Parc national de Bukit Barisan Selatan (PNBBS à Sumatra en Indonésie. Nous avons étudié 55 grilles (72,25 km 2 ) entre novembre 2007 et juillet 2008 pour produire une estimation fiable de la proportion de la superficie occupée (occupation) par le rhinocéros de Sumatra. On a enregistré des signes de rhinocéros (par exemple, des empreintes, des crottes, des torsions d’arbres et des vautrements) le long de 833 km des transects et on a utilisé l’intervalle d’échantillonnage de 1 km afin de développer une histoire de détection/non-détection pour chaque grille. On a détecté des signes de rhinocéros dans 11 grilles produisant une occupation naïve de 0,2. Une modélisation de l’occupation a été utilisée pour contrôler la probabilité de détection imparfaite (P). En se basant sur le modèle d’hétérogénéité de Royle/Nichols, nous avons conclu que le rhinocéros de Sumatra occupait environ 32% de la superficie du PNBB (SE = 0,09). L’occupation peut servir comme un substitut robuste pour un indice d’abondance dans un cadre de surveillance de la population. Une analyse plus approfondie utilisant les modèles multi-saisonniers de la technique sur les données de séries chronologiques et des covariables spécifiques saisonnières/par études peuvent fournir aux autorités de gestion des informations précises sur l’évolution des populations de rhinocéros et aider à prioriser les mesures de conservation pour le rhinocéros de Sumatra dans la région.
Chemical horn infusions: a poaching deterrent or an unnecessary deception?
Authors: Ferreira Sam , Hofmeyr Markus , Pienaar Danie , Cooper Dave
Published: November 2024

Poaching for horn remains a significant threat to rhinos. Conservationists use various approaches to deal with the threat. One method advocated is infusing rhino horns with chemicals and dye. Promoters of this method claim the procedure renders the horn useless and that ingesting poisoned horn carries potential risk to the end-user. We visually examined white rhino horn that had been treated; we examined available literature; and we obtained expert opinion to assess several assumptions and risks associated with the approach. We found the information on which the assumptions are based to be weak, and refute claims that discolouring horns is a viable method. Our assessment contests the efficacy of this technique on conceptual and logistical grounds, especially when dealing with relatively large populations. We argue that conservationists should not use this technique to deal with the rhino poaching threat.
Le braconnage pour la corne reste une menace importante pour les rhinocéros. Les écologistes utilisent différentes approches pour faire face à la menace. Une des méthodes préconisées est l’infusion des cornes de rhinocéros avec des produits chimiques et des colorants. Les partisans de cette méthode affirment que cette procédure rend la corne inutile. Cependant, elle comporte également un risque potentiel à l›utilisateur final quand il ingère la corne empoisonnée. Nous avons examiné visuellement la corne de rhinocéros blanc qui avait été traitée, et nous avons examiné la documentation disponible et obtenu l›avis des experts pour évaluer plusieurs hypothèses et les risques associés à la démarche. Nous avons trouvé que l›information sur laquelle les hypothèses sont fondées n’était pas correcte, et nous réfutons les allégations selon lesquelles la décoloration des cornes est une méthode viable. Notre évaluation conteste l’efficacité de cette technique pour des raisons conceptuelles et logistiques, surtout lorsqu’il s’agit de populations relativement importantes. Nous soutenons que les écologistes ne doivent pas utiliser cette technique lorsqu’ils sont confrontés à la menace du braconnage de rhinocéros.