Pritpal Soorae

Reversing defaunation: Restoring species in a changing world

The rate of biodiversity loss is not slowing despite global commitments, and the depletion of animal species can reduce the stability of ecological communities. Despite this continued loss, some substantial progress in reversing defaunation is being achieved through the intentional movement of animals to restore populations. We review the full spectrum of conservation translocations, from reinforcement and reintroduction to controversial conservation introductions that seek to restore populations outside their indigenous range or to introduce ecological replacements for extinct forms. We place the popular, but misunderstood, concept of rewilding within this framework and consider the future role of new technical developments such as de-extinction.

Taxonomic bias in reintroduction projects

Taxonomic bias has been documented in general science and conservation research publications. We examined whether taxonomic bias is similarly severe in actual conservation programmes as indicated by the focus of species reintroduction projects worldwide. We compiled a database of reintroduction projects worldwide, yielding a total of 699 species of plants and animals that are the focus of recent, current or planned reintroductions. Using IUCN (World Conservation Union) data for total numbers of known species worldwide, we found that vertebrate projects were over-represented with respect to their prevalence in nature. Within vertebrates, mammals and, to a lesser extent, birds, were over-represented, whereas fish were under-represented. This over-representation extended to two mammal orders, artiodactylids and carnivores, and to four bird orders, anseriforms, falconiforms, gruiforms and galliforms. For neither mammals nor birds was reintroduction project bias related to any differences between orders in vulnerability to threat. Bird species that are the focus of reintroduction efforts are more likely to be categorised as ‘Threatened’ than expected on the basis of the distribution of all known species over all threat categories, however, nearly half of all bird species being reintroduced are classified as ‘Least Concern’. The selection of candidates for reintroduction programmes is likely to consider national priorities, availability of funding and local community support, over global conservation status, While a focus on charismatic species may serve to garner public support for conservation efforts, it may also divert scarce conservation resources away from taxa more in need of attention.

The Risks of Assisted Colonization

There is a growing debate over whether species should be translocated outside their historic ranges to deal with extinction risks as habitats shift due to climate change. This idea of taking preemptive action to avert predicted extinction risks has been given emphasis by the recent International Union for Conservation of Nature (IUCN) assessment of species susceptibility to climate-change impacts (Foden et al. 2008), prompting suggestions that “more aggressive measures, such as so-called ‘assisted migration’” be considered (Marris 2008). Hoegh-Guldberg et al. (2008) provide a decision framework for identifying scenarios in which what they term “assisted colonization” (AC) is justified. We see problems with the impact of these articles, despite their conservative approach. First, there are current international translocation guidelines (IUCN 1998) that provide a strong rationale against the early adoption of AC as a conservation tool. The Reintroduction Specialist Group (RSG) was created in 1988 to address the proliferation of ill-conceived translocations that had been taking place, including many releases of species outside historic ranges (Stanley Price & Soorae 2003). The RSG formulated the guidelines for translocation planning to ensure that conservation benefits accrue. “Benign introduction” (BI)—the translocation of species to suitable habitat outside their historic range as a conservation measure—was considered appropriate only when there was no habitat left within the original species range (IUCN 1998). Although AC appears to fall within the definition of BI, the two differ in that AC aims proactively to establish species outside their historic range to preempt predicted climate-driven changes in habitat suitability. Calls to take proactive conservation measures need to consider that there are currently huge uncertainties involved, not only in climatechange predictions and consequent species responses (Araújo et al. 2005; Hulme 2005; Sekercioglu et al. 2008) but also in our understanding of the habitat requirements of species (Stamps & Swaisgood 2007) and the effects of translocations on ecosystem function (Armstrong & Seddon 2008). At a recent conference (First International Wildlife Reintroduction Conference, Lincoln Park Zoo, Chicago, Illinois,April2008, http://www. reintroduction.org/), RSG members discussed climate-change implications for translocations, acknowledging the need for the integration of reintroduction biology and restoration ecology, and the updating of translocation guidelines to consider issues such as the mitigation of climate-driven habitat change and overcoming barriers to natural dispersal of species. Given current uncertainty, however, there is substantial risk that prematurely embracing the undeniably sexy AC concept will initiate a new era of ill-conceived species translocations. Philip J. Seddon,∗ Doug P. Armstrong,† Pritpal Soorae,‡ Frederic Launay,§ Sally Walker,∗∗ Carlos R. Ruiz-Miranda,†† Sanjay Molur,∗∗ Heather Koldewey,‡‡ and Devra G. Kleiman§§ ∗RSG Bird Section Chair, Department of Zoology, University of Otago, Dunedin, New Zealand, email philip.seddon@stonebow. otago.ac.nz †RSG Australasia Chair, Massey University, Palmerston North, New Zealand ‡RSG Programme Officer, Environment Agency, Abu Dhabi, United Arab Emirates §RSG Chair, Environment Agency, Abu Dhabi, United Arab Emirates ∗∗RSG South Asia co-Chair, Zoo Outreach, Coimbatore, India ††RSG Meso-South America Chair, Environmental Sciences Laboratory, Universidade Estadual do Norte Fluminense, Rio de Janeiro, Brazil ‡‡RSG Fish Section Chair, Zoological Society of London, London, United Kingdom §§RSG North America Chair, Zoo-Logic, Chevy Chase, MD 20815, U.S.A.

A herpetological survey of some islands in the Arabian Gulf, Abu Dhabi Emirate, United Arab Emirates

Abstract Five species of geckos (Bunopus tuberculatus, Crytodacylus scaber, Hemidactylus flavivirdis, H. turcicus, and Pristurus rupestris), one lizard species (Mesalina brevirostris) and three snake species (Eryx jayakari, Coluber ventromaculatus and Psammophis schokari) were recorded on a total of 13 islands during a herpetological survey conducted in 2003–2004 in the Arabian Gulf, Abu Dhabi Emirate. The distribution and abundance of these species is also described in detail. Bunopus tuberculatus and Mesalina brevirostris are more commonly distributed on the islands and the remaining gecko species are limited only to certain islands, whilst the three snake species were recorded only on one island.

Records of sea snakes (subfamily Hydrophiinae) from the coastal waters of the Abu Dhabi Emirate, United Arab Emirates

(2006). Records of sea snakes (subfamily Hydrophiinae) from the coastal waters of the Abu Dhabi Emirate, United Arab Emirates. Zoology in the Middle East: Vol. 39, No. 1, pp. 109-110.

Distribution and ecology of the Arabian and Dhofar Toads (Duttaphrynus arabicus and D. dhufarensis) in the United Arab Emirates and adjacent areas of northern Oman

Records of the Arabian Toad (Duttaphrynus arabicus) and the Dhofar Toad (Duttaphrynus dhufarensis) in the UAE and adjacent areas of northern Oman are mapped and some recent observations presented. The Arabian Toad is more widely distributed in more mesic habitats and benefits from the increase in artificially irrigated habitats. The Dhofar Toad is able to live in drier areas but its distribution pattern suggests it may be outcompeted by the Arabian Toad in wetter areas with greater availability of surface water.

First record of Epipactis veratrifolia Boiss. & Hohen. (Orchidaceae, Epidendroideae, Neottieae, Limodorinae) from an arid wadi in Abu Dhabi, United Arab Emirates

Epipactis veratrifolia is recorded for the first time from Jebel Hafeet, a mountain in Abu Dhabi, United Arab Emirates (UAE). This species had been previously recorded from the northern part of the UAE and other areas on the Arabian Peninsula. The occurrence of E. veratrifolia in Jebel Hafeet expands the eastern distribution limits of the species and underlines the importance of biodiversity in the region. The new record fills a gap in the distribution of this species on the Arabian Peninsula.

Floristic composition of arid off –shore islands in Abu Dhabi, United Arab Emirates

Data on flora and vegetation of 14 off-shore islands representing different habitat types were studied for investigating floristic composition, vegetation types and correlation with their habitats and ecosystem. The results demonstrate considerable plant distribution and diversity among the islands within the limited spectrum of species; encompassing a total of 47 species, belonging to 43 genera under 24 families. The most representative families were Amaranthaceae (9 species), Fabaceae (4 species), Poaceae (4 species) and Asteraceae and Aizoaceae (3 species each). Fourteen families are represented by only one species. The mangrove species, Avicennia marina, occurs throughout the coast of Abu Dhabi in discontinuous patches and in different water salinities. The studies also seek to underline that dominant species that constitutes the flora of Abu Dhabi are salt tolerant in nature. Compared to other Arabian Peninsula ecosystems, UAE perhaps has a higher coastal: mainland area ratio, which has contributed to a natural dominance of salt tolerant species among the community. The studies show 40% similarity among islands with respect to the species diversity. The floristic composition of the off-shore islands also indicates a need to consider these sites as protected sites.