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Thursday, 5 January 2017
Vegetative habitat selection of Scimitar horned oryx (Oryx dammah) in Bouhedma National Park, Southern Tunisia
Published Date
Journal of King Saud University - Science July 2016, Vol.28(3):261–267,doi:10.1016/j.jksus.2016.04.003 Special Issue on Abundance Estimation in an Arid Environment Open Access, Creative Commons license,Funding information ORIGINAL ARTICLE Author
Houssem chedli Traouit Beyouli a,b,,
Mohamed Neffati a
aRangeland Ecology Laboratory, Institut des Régions Arides (IRA), 22,5 km Route de Djorf, 4119 Médenine, Tunisia
bInstitut National Agronomique de Tunisie (INAT), 43, Avenue Charles Nicolle, 1082 Tunis, Tunisia
Received 1 October 2014. Accepted 15 April 2016. Available online 23 April 2016.
Abstract
The present study aims to analyze the habitat selection of the Scimitar horned oryx, reintroduced in Bouhedma National Park (south Tunisia) and to identify the phytoecological factors affecting their occurrence during winter 2011 and spring 2012. Multivariate analyses of variance (MANOVA) performed by SAS package revealed that the vegetation is not the main factor in the selection of habitat by oryx in the park. It avoids glaze and mountain areas despite the presence of palatable species.
Keywords
Scimitar horned oryx
Habitat selection
Vegetation cover
Bouhedma National Park
1 Introduction
The world is currently facing an unprecedented loss of biodiversity, hundreds of species already driven to extinction by anthropogenic and climatic changes, and thousands more predicted to become extinct in the next few decades (Lande, 1993). In Tunisia, animal diversity has experienced huge losses affecting several species. The most striking example is the Scimitar horned oryx (Oryx dammah: Class mammalian, order ungulata) which is classified as Extinct in Wild (IUCN, 2008) after the degradation of their native habitats (Kacem et al., 1994). Historically, the Scimitar horned oryx was largely distributed along the fringes of the northern and southern sub-desert (Devillers and Devillers-Terschuren, 2003), particularly in arid landscapes bordering Saharan habitats (Gilbert et al., 2012). Scimitar horned oryx can be found in a variety of habitats types including, grassy steppes, rolling dunes and wooded inter-dunal depressions (IUCN, 2008). The main reasons for the decline of this ungulate species in its native range are overhunting, droughts and habitat loss, including competition with domestic livestock (Mallon and Kinkswood, 2001 and Devillers and Devillers-Terschuren, 2006).
In Tunisia, Scimitar horned oryx occurred across southern steppes, but disappeared by 1910 due to overhunting. Since its independence in 1956, the Tunisian Government has been engaged in the rehabilitation of Scimitar horned oryx population through the development of appropriate legislation, signing the convention on Migratory species (CMS) (Beudels-Jamar et al., 2006, DGF, 2001 and Woodfine and Engel, 2005) and creation of a network of protected areas in which several operations of reintroduction of this ungulate were performed (Karem, 2001), starting with reintroduction of 10 (5 males and 5 females) Scimitar horned oryx in the Bouhedma National Park in 1985 (Wacher, 1986). The population grew to a point when ungulates exerted pressure on the canopy, especially, on grassland species. A number of questions were subsequently raised concerning the space use, the social and food behavior and the relationship of Scimitar horned oryx with environment. Furthermore, studies on habitat selection and habitat use patterns are essential for understanding the strategies of animals to fulfill their needs (Manly et al., 2002). They are also crucial for conservation and management strategies (Scott et al., 2002 and Guisan and Thuiller, 2005) that can reduce the negative effects of plant damage caused by inadequate population densities (Heinzea et al., 2011).
However, information about habitat selection by oryx in Tunisian protected areas is scarce and insufficient to develop such conservation and management strategies for the animal. The present study was designed to understand the preference of Scimitar horn oryx in Bouhedma National Park with the hypothesis that occurrence of oryx depends on the vegetation type. The main objectives were: (1) to relate patterns of habitat selection by Scimitar horned oryx with vegetative cover characteristics, and (2) to identify the most attractive plants for the oryx in the park.
2 Material and methods
2.1 Study area
This research work was carried out in the protected area No. 1 (5115 hec) of Bouhedma National Park which covers a total of 16,488 hec (Fig. 1). This park is situated in the central Tunisia (34°24′–34°32′ NL; 09°23′–09°41′ E) and located along the southern Tunisian mountain ranges which are extensions of the Saharan Atlas (Abdelkebir, 2005). The altitude varies between 90 m and 814 m above sea level. The climate is arid with mild winters. The park is characterized by an extremely irregular spatiotemporal rainfall pattern with an annual average rainfall of about 150 mm.
Figure 1. Geographic location of the study area.
Bouhedma National Park is considered as a transition zone which holds Mediterranean, pre-Saharan and Saharan animal species. The animal species of the park include some reintroduced species, such as, Oryx dammah, Addax nasomaculatus, and Gazella dorcas, and several indigenous species, like, Ctenodactylus gundi, Jaculus deserti, Canis aureus and Vulpes rueppellii (Müller, 1994). The park also houses Sus scrofa, Lepus capensis, Rattus norvegicus and 16 other rodent species. The total number of Scimitar horned oryx in the study area was 31 (5 males and 26 females).
On the mountainous massif, vegetation is dominated by forest species such as Juniperus phoenicea, Periploca angustifolia, Rhus tripartitum, Olea europaea, Rosmarinus officinalis and Stipa tenacissima. Artemisia herba-alba, Anarrhinum brevifolium, Gymnocarpus decanter and Helianthemum kahiricum colonize the piedmont. The flat area is dominated by pseudo-savannah vegetation with Acacia tortilis raddiana as the only tree species, and understorey stratum is dominated by species, like, Rhanterium suaveolens, Cenchrus ciliaris, Haloxylon schmittianum, H. scoparium and Salvia aegyptiaca (OuledBelgacem et al., 2013).
2.2 Measurement and data collection
Scimitar horned oryx was systematically monitored for 10 days every month between November 2011 and April 2012. The survey was conducted during morning and evening sessions. The study area was divided into a number of sampling units (1 km2: Fig. 2) according to the stratified sampling theory (Maling, 1989), and the oryx was recorded on presence (1: tracks or droppings) and absence (0) basis in each sampling unit (Dajoz, 1996). This method seems to be effective, especially when applied on a small population (Vaucher, 1988).
Figure 2. Sampling unit map of Bouhedma National Park.
Vegetation cover data were extracted from the phyto-ecological map of the park developed by Tarhouni (2003) (Fig. 3).
Figure 3. Vegetation map of Bouhedma National Park (Tarhouni, 2003).
2.3 Statistical analysis
Multivariate analysis of variance (MANOVA) using general linear model (GLM) procedure was used for data analysis exploiting the SAS statistical package (SAS Institute, 1998). The plant communities were taken as original variables. We calculated their proportions in each sampling unit.
A canonical discriminant analysis was also performed with SAS statistical package in order to verify the results of MANOVA and to evaluate the significance of importance variables in explaining the occurrence distribution pattern of oryx.
3 Results
The effect of plant communities on the occurrence of Scimitar horned oryx is shown in Table 1.
Table 1. MANOVA analysis of the occurrence plant groups (PG) in Scimitar horned oryx unoccupied and occupied sites in Bouhedma National Park.
With: PG1: Anarrhinum brevifolium and Moricondia suffruticosa, PG2: Artemisia herba alba and Haloxylon scoparium, PG3: Phoenix dactylifera, PG4: Eucalyptus, PG5: Gymnocarpus decanterand Atractylis serratuloides, PG6: Gymnocarpus decanter, PG7: Haloxylon schmittianum and Echichilon fruticosum, PG8: Haloxylon schmittianum and Haloxylon scoparium, PG9: Haloxylon schmittianum and Rhanterium suaveolens, PG10: Nursery plants, PG11: Exotic plantation, PG12: Retama raetam, PG13: Rhanterium suaveolens and Artemisia campestris, PG14: Stipa tenacissima, PG15: Stipa tenacissima and Periploca angustifolia, PG16: Stipa tenacissima and Rosmarinus officinalis, PG17: Stipa tenacissima and Gymnocarpus decanter, PG18: Stipa tenacissima, Juniperus Phoenicea and Olea europa, PG19: Ziziphus lotus and Retama raetam.
⁎
Significant difference: p < 0.05.
MANOVA analysis showed a significant difference between the occupied and the unoccupied sites (Wilks’ Lambda = 0.1815, F14,19 = 3.32, P = 0.0132). PG2 (P = 0.02), PG14 (P = 0.04), PG15 (P = 0.03), PG16 (P = 0.01) and PG18 (P = 0.048) plant groups were significantly associated with oryx unoccupied tracts, all holding Stipa tenacissima. It appears that Scimitar horned oryx doesn’t use the sites having a cover of this perennial grass.
The evaluation of discriminant capacities of the different plant groups using “STEPDISC” analysis (Table 2) reveals that PG14 (P = 0.022), PG15 (P = 0.017), PG16 (P = 0.033) and PG18 (P = 0.038) plant groups are different between the occupied and the unoccupied sites. Following this analysis, PG2 has been excluded.
Table 2. STEPDISC analysis of difference in occurrence of different plant groups (PG) in Scimitar horned oryx occupied and unoccupied sites of Bouhedma National Park.
With: PG1: Anarrhinum brevifolium and Moricondia suffruticosa, PG2: Artemisia herba alba and Haloxylon scoparium, PG3: Phoenix dactylifera, PG4: Eucalyptus, PG5: Gymnocarpus decanterand Atractylis serratuloides, PG6: Gymnocarpus decanter, PG7: Haloxylon schmittianum and Echichilon fruticosum, PG8: Haloxylon schmittianum and Haloxylon scoparium, PG9: Haloxylon schmittianum and Rhanterium suaveolens, PG10: Nursery plants, PG11: Exotic plantation, PG12: Retama raetam, PG13: Rhanterium suaveolens and Artemisia campestris, PG14: Stipa tenacissima, PG15: Stipa tenacissima and Periploca angustifolia, PG16: Stipa tenacissima and Rosmarinus officinalis, PG17: Stipa tenacissima and Gymnocarpus decanter, PG18: Stipa tenacissima, Juniperus Phoenicea and Olea europa, PG19: Ziziphus lotus and Retama raetam.
⁎
Significant difference: p < 0.05.
The examination of the important different variables using DISCRIM PROC analysis (Table 3) indicates that PG14, PG15, PG16 and PG18 are highly discriminating variables (Wilks’ Lambda = 0.18, F = 3.82, P = 0.004, canonical correlation coefficient = 0.90) confirming MANOVA and STEPDISC results.
Table 3. Occurrence probability of Scimitar horned oryx according to the plant groups of Bouhedma National Park: “DISCRIM” analysis.
With: PG1: Anarrhinum brevifolium and Moricondia suffruticosa, PG2: Artemisia herba alba and Haloxylon scoparium, PG3: Phoenix dactylifera, PG4: Eucalyptus, PG5: Gymnocarpus decanterand Atractylis serratuloides, PG6: Gymnocarpus decanter, PG7: Haloxylon schmittianum and Echichilon fruticosum, PG8: Haloxylon schmittianum and Haloxylon scoparium, PG9: Haloxylon schmittianum and Rhanterium suaveolens, PG10: Nursery plants, PG11: Exotic plantation, PG12: Retama raetam, PG13: Rhanterium suaveolens and Artemisia campestris, PG14: Stipa tenacissima, PG15: Stipa tenacissima and Periploca angustifolia, PG16: Stipa tenacissima and Rosmarinus officinalis, PG17: Stipa tenacissima and Gymnocarpus decanter, PG18: Stipa tenacissima, Juniperus Phoenicea and Olea europa, PG19: Ziziphus lotus and Retama raetam.
⁎
Significant difference: p < 0.05.
On the basis of the results obtained, the spatial distribution of oryx in Bouhedma National Park seems to be related to some plant groups. We have noted that the areas not frequented by oryx (unoccupied sites) were all marked by the presence of Stipa tenacissima plant. This plant appears to be rejected by the animal despite its known high palatability. This finding allowed us to reject our starting hypothesis and to consider that vegetation cover cannot be the determinant factor of habitat selection by oryx in the park. However, as this palatable plant grows generally in piedmonts and in mountains, we considered that at that stage of study elevation might be the major determinant factor in oryx distribution.
4 Discussion
Studying habitat selection by Scimitar horned oryx is fundamental for its management and conservation of this ungulate in a protected area, such as Bouhedma National Park. The research was designed to determine the influence of plant groups on the habitat use by oryx. The present collected results show that oryx abundance is associated with vegetation type (Cooke et al., 2014). Zweifel-Schielly et al. (2009)recorded the importance of access to and/or availability of good quality forage in habitats selected by ungulates. Freitas et al. (2008) highlighted the importance of the analysis of the vegetation attribute in comparison.
However, our results suggested that vegetation is not the key factor affecting habitat selection by oryx in Bouhedma National Park. It turns out that Scimitar horned oryx population tends to use the plain of the park covering more than 2000 hectares and avoids the areas with high and medium elevation despite the presence of palatable plant, like, Stipa tenacissima (especially in drought periods) (Caron, 2001), and Helianthemum sp. Other plants, as Retama raetam and Periploca angustifolia, growing in the piedmonts and the mountain provide refuge area to Scimitar horned oryx. Kacem et al. (1994) indicated the importance of Stipa tenacissima and Stipagrostis steppes characterizing the mountains and the glaze of Bouhedma National Park (Tarhouni, 2003) in the reintroduction of oryx in the Mediterraneo-Saharan fringe. The present results support those of Beudels-Jamar et al. (2006) who consider that Scimitar horned oryx as a typical species of steppe and grasslands bordering desert areas. It often avoids significantly mountainous areas and prefers flat deserts over hilly or stone deserts (Dolan, 1996). Abáigara et al. (2013) have also suggested the tendency of dorcas gazelle (Gazella dorcas) to prefer open plain areas, an adaptation for an early detection of predators (jackals). Indeed, herbivores choose generally their habitats both to maximize forage intake and to minimize their risk of predation (Riginos and Grace, 2008). It has been proved that predation can be a major obstacle to the reintroduction and the conservation of these ungulate in protected areas (Dhaoui et al., 2008 and Dunham, 1997).
On the other hand, the plain area of Bouhedma National Park, marked by silty and sandy soils, is more comfortable for the displacement of Scimitar horned oryx than mountains and piedmonts (high elevation). We conclude that scimitar-horned oryx selects lower wadis and plains due to richer habitat, shade and lower predation risk rather than directly due to the effects of altitude. Further, it has been reported that the abiotic components of habitat, such as, climate and elevation, influence habitat selection at a large-scale, while the biotic factors, such as, food quantity and quality, affect habitat selection at small scales (Senft et al., 1987 and Bailey et al., 1996). Finally, the measurement of habitat conditions including food availability and biological requirements of the species, as well as predators, competitors and parasites is important to determine the persistence of a reintroduced population (Amstrong and Seddon, 2008) and to be aware of the degree of success of introduction projects.
5 Conclusion
The results obtained allowed us to conclude that at a larger scale vegetation is not the determinant factor in the habitat selection of Scimitar horned oryx in Bouhedma National Park. It is mainly controlled by other factors such as elevation and predation. Therefore, a quantitatively assessment of the vegetation cover/type asses in the plain of the park could be more effective in the determination of the role of plant cover in habitat selection by Scimitar horned oryx.
Acknowledgements
This study was carried out at Rangeland Ecology Laboratory, Institut des Régions Arides de Médenine, Tunisia. We would like to thank Pr. Houcine Khatteli, Director General of (IRA), for giving us the opportunity to work at this Institute. We would like to thank Mr. LazharHamdi (Conservator of Bouhedma National Park) for his contribution in this work. We thank the editor and an anonymous reviewer for their constructive comments, which helped us to improve the manuscript.
Caron, S., 2001. Suivi écologique de l’Oryx algazelle (Oryx dammah) dans le parc National de Bou-Hedma (Tunisie) et notes sur les autres Ongulés sahélo-Sahariens du parc. Travail de fin d’étude en vue de l’obtention du grade académique de Diplôme d’Etudes Supérieures Spécialisées Université des Sciences et technologies de Lille (France).
Devillers, P., Devillers-Terschuren, J., 2003. Report on the status and perspectives of a species, Oryx dammah. In: Conservation measures for Sahelo-Saharan Antelopes. Action plan and status reports. CMS, Technical Series Publication.
Sahelo-Saharan Antelopes. Status and Perspectives. Report on the conservation status of the six Sahelo-Saharan Antelopes, R.C. Beudels, P. Devillers, R.M. Lafontaine, J. Devillers-Terschuren, M.O. Beudels, CMS SSA Concerted Action, second ed., 2006, CMS Technical Series Publication N° 11, UNEP/CMS Secretariat, Bonn, Germany
Dhaoui, M., Aissa, P., Hamdi, L., 2008. Impact de la prédation par lechacal (Canis aureus) sur l‟effectif des Antilopes d’Oryx dammah et l’Addax nasomaculatus réintroduites dans espace pré-saharien au Sud Tunisien (Cas du Parc National de Bou Hedma-Haddèj). SSIG Annual Meeting, AlAin Zoo, EUA.
Kacem, S.B.H., Müller, H.P.R., Wiesner, H., 1994. Gestion de la faune sauvage et des parcs nationaux en Tunisie. Réintroduction, gestion et aménagement. Eschborn, GTZ.
Mallon, D.P., Kinkswood, S.C., 2001. Antelopes. Part 4: North Africa, the Middle East, and Asia. Global Survey and Regional Action Plans. SSC Antelope Specialist Group. IUCN, Gland, Switzerland and Cambridge, UK. viii p. 260.
Müller, H.P., 1994. NationalparkSouss-Massa. Wiedereinbürgerung von Mendesantilopen und Mhorrgazellen. Royaume du Maroc. Ministère de l’Agriculture et de la Mise en Valeur Agricole. Direction des Eaux et Forêts et de la Conservation des Sols. Rabat.
Tarhouni, M., 2003. Cartographie des systèmes écologiques et étude de la dynamique de l’occupation des terres dans le parc national de BouHedma. Mémoire de DEA, faculté des sciences de Sfax.
Wacher, T.J., 1986. The reintroduction of scimitar-horned oryx, Oryx dammah, from the United Kingdom to Tunisia. Zoological Society of London, Report No. 2. April–May, pp. 1–18.
Woodfine, T., Engel, H., 2005. Reintroduction and metapopulation of addax and oryx in Tunisia. In: Monfort, S., Correll, T. (Eds.), Proceedings of the fifth annual Sahelo-Saharan Interest Group Meeting, Sousse, Tunisia.
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