Conflicting Management Policies for the Arabian Wolf Canis Lupus Arabs in the Negev Desert: Is This Justified?
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Conflicting management policies for the Arabian wolf Canis lupus arabs in the Negev Desert: is this justified? O RLY C OHEN,ADI B AROCAS and E LI G EFFEN Abstract Conservation plans may conflict when both littoralis. The arrival and spread of the golden eagle Aquila predator and prey in the same ecological system are chrysaetos to these islands in the 1980s, facilitated by the threatened species. In this study we present a problematic availability of the previously introduced feral pig Sus scrofa case of conflicting conservation policies involving the as prey, led to a drastic decline in fox numbers (Roemer Arabian wolf Canis lupus arabs and two species of gazelles et al., 2002), to the point that breeding programmes were (Gazella gazella acaciae and Gazella dorcas), all of which are established to save the fox from extinction. The dilemma threatened in Israel. By studying genetic subdivision using was: should the golden eagle, which is a protected species, be faecal DNA we evaluated the policy of treating the Arabian removed to save another protected species, the island fox? wolves in the Negev Desert as two separate populations. To mitigate the decline in fox numbers, golden eagles were We analysed 95 wolf faecal samples from 12 feeding sites translocated, and feral pigs eradicated from the islands c. 20 km apart. Network analysis and Bayesian clustering (Courchamp et al., 2003). A similar case in these Channel were used for separating populations. Mark–recapture Islands is that of the threatened San Clemente loggerhead design, rarefaction and an urn model were applied to shrike Lanius ludovicianus mearnsi, which is predated by estimate wolf population size. We found that wolves in the the island fox; a control programme was established to save central and southern Negev cannot be genetically separated, the shrike (Roemer & Wayne, 2003). and their density is similar in both regions. Our results Predator removal is commonly practised by wildlife provide a better baseline for a unified management of managers. A recent review suggested that predator removal wolves in the Negev. We call for the consideration of other increased hatching and fledging success and breeding factors influencing gazelle population size before adopting populations of birds (Smith et al., 2010). Predation by wolf drastic measures such as wolf removal. Canis lupus, puma Puma concolor and coyote Canis latrans may be a significant mortality factor for medium or large Keywords Carnivore removal, Israel, Middle East, non- ungulates (e.g. deer, caribou Rangofer tarandus, moose Alces invasive sampling, population size, population subdivision, alces) in some areas under certain conditions (reviewed in scatology Ballard et al., 2001). A predator removal programme may This paper contains supplementary material that can be not affect prey populations that are near carrying capacity found online at http://journals.cambridge.org/orx but may significantly increase ungulate populations that are substantially below carrying capacity. Thus results of predator removal practice are confounded by numerous Introduction factors and only through intensive studies can predation be ff identified as a major limiting factor (Ballard et al., 2001). great deal of e ort goes into protecting threatened 2011 ff Aand/or important species. In some cases several Wasser et al. ( ) studied the e ect of predator removal on threatened species can be protected under the same caribou populations and concluded that management programme. Nevertheless, when these threatened species should prioritize the control of human activities before include both predator and prey in the same ecological implementation of more extreme actions such as removal of fl wolves. In other words, resource selection and its physio- system there may be potential con ict of management fi fl – plans. This is illustrated by examples from the Channel logical consequences can signi cantly in uence predator Islands off the Californian coast. These islands were prey interactions, and should be considered in management previously densely populated by the island fox Urocyon programmes that aim to manipulate complex ecosystems. In this study we present a problematic case of conflicting conservation policies involving several threatened species. ORLY COHEN,ADI BAROCAS* and ELI GEFFEN (Corresponding author) A small isolated population (20–30 individuals) of the 2 Department of Zoology, Tel Aviv University, Tel Aviv 69978, Israel. E-mail mountain gazelle Gazella gazella acaciae inhabits a 6 km geff[email protected] acacia forest near Yotvata in the southern Arava Valley, *Also at: Program in Ecology and Department of Zoology and Physiology, 1987 2004 University of Wyoming, Laramie, Wyoming, USA Israel (Yom-Tov & Ilani, ; Dolev & Perevolotsky, ). A recent genetic survey of gazelles in the Middle East Received 3 August 2011. Revision requested 25 November 2011. Accepted 6 December 2011. showed that this isolated population is genetically different © 2013 Fauna & Flora International, Oryx, 47(2), 228–236 doi:10.1017/S0030605311001797 Arabian wolf in the Negev Desert 229 from the mountain gazelle Gazella gazella gazella in garbage containers inside settlements and army camps. The northern Israel but similar to G. gazella from northern South district, on the other hand, did not cull wolves and Saudi Arabia (Wronski et al., 2010). This Critically did not control access of wolves to local rubbish pits. Endangered G. g. acaciae population has been in decline Consequently, while the Eilat district attempted to reduce since the 1960s, presumably because of low calf survival, low the wolf population to a minimum, the management genetic diversity, anthropogenic effects and climate change exercised by the South district counteracted this. The (Yom-Tov & Ilani, 1987; Dolev & Perevolotsky, 2004; IUCN, above actions taken by INPA raise a question: how can a 2008a). The congeneric dorcas gazelle Gazella dorcas is a single population be managed by two contradictory more common species in the Negev but at a regional scale it policies? To address this issue we studied the genetic is categorized as Vulnerable (Dolev & Perevolotsky, 2004; population structure and estimated population size using IUCN, 2008b) because of intensive motorized hunting and faecal DNA. Specifically, we examined whether the wolf habitat degradation caused by overgrazing and droughts population in the two INPA districts has similar densities (Mallon & Kingswood, 2001). The law in Israel protects both and genetic composition. The findings of our study offer a gazelle species and poaching in the south of Israel is rare. new and reliable baseline for modification of the current The main alleged cause for the decline of both the mountain INPA management policy for the Arabian wolf in the Negev and dorcas gazelles in the Negev is predation by the Arabian Desert. Furthermore, our results can shed light on the effects wolf Canis lupus arabs and the caracal Caracal caracal,a of different management policies on the population genetics hypothesis based on anecdotal data (Shalmon, 2003, 2006). of a threatened species. The mountain and dorcas gazelles differ in their laying-up period, which is longer in the mountain gazelle, suggesting greater vulnerability of mountain gazelle fawns to predation Study area (Mendelssohn et al., 1995; Yom-Tov et al., 1995). In response The central and southern Negev is a rocky desert, a mixture to the decline in gazelle populations in the southern Negev of mountains, washes, and depressions. The 160 km Arava the Israel Nature and Parks Authority (INPA; the govern- Valley, an elongated depression of the Rift Valley, borders ment agency that manages all natural resources in Israel) the Negev in the east. Elevation in the mountainous regions instigated a wolf removal programme that eliminated is 400–1,000 m, falling to 50–150 m at the bottom of the Rift. 37 individuals from the area during 2005–2008.Bymid The climate is hot and arid, with an annual rainfall of 2006 the isolated and small population of the mountain 50–100 mm, falling during the winter months of November– gazelle was completely fenced and the wolf removal March (Evenari et al., 1982). There are two cities, Eilat programme was terminated in early 2008. (population 50,000) at the northern tip of the Red Sea, and Although C. lupus is categorized as Least Concern on Mitzpe Ramon (population 6,000) in the Negev highlands. the IUCN Red List (Mech & Boitani, 2010), the Arabian All other settlements are agricultural communities (10 in the subspecies is threatened regionally and is vulnerable locally Eilat district and eight in the South district), mostly in the (Dolev & Perevolotsky, 2004; Sillero-Zubiri et al., 2004) Rift Valley. because of systematic shooting and trapping (Mendelssohn, 1983; Cunningham & Wronski, 2010). In Israel the Arabian wolf is fully protected by law and is not persecuted except Methods for specific management actions. Although Hefner & ff 1999 Ge en ( ) have studied some behavioural aspects of Sample collection this subspecies, no reliable demographic data are available. Hefner & Geffen (1999) documented the dispersal of To sample wolf scats equally over the central and southern individuals over 50–150 km, suggesting a continuous ad- Negev Desert we established a grid of 12 feeding sites mixture between wolves in the southern and central Negev c. 20 km apart. Five feeding sites were established in the Eilat 2 and the likelihood that the wolves in the Negev Desert district (sampling an area of c. 2,129 km ) and seven in the 2 comprise a single population. South district (sampling an area of c. 2,910 km ; Fig. 1). In Israel is divided into four INPA districts that are setting out this grid of feeding sites we also considered relatively independent of each other but controlled by a vehicle accessibility and other entry restrictions. Mean 2 single directing body. The 13,000 km Negev Desert, which home range size of Arabian wolves in the Negev Desert is 2 covers more than half of Israel, is divided into two INPA 34.6 ± SD 19.5 km and mean daily travel distance is districts (Fig.