Biological richness of Gunung Slamet, Central Java, and the need for its protection C HRISTIAN D EVENISH,ACHMAD R IDHA J UNAID,ANDRIANSYAH,RIA S ARYANTHI S. (BAS) VAN B ALEN,FAJAR K APRAWI,GANJAR C AHYO A PRIANTO R ICHARD C. STANLEY,OLIVER P OOLE,ANDREW O WEN N. J. COLLAR and S TUART J. MARSDEN Abstract Designating protected areas remains a core strategy we discuss different options for improving the protection in biodiversity conservation. Despite high endemism, mon- status of Gunung Slamet, including designation as a tane forests across the island of Java are under-represented National Park or Essential Ecosystem. in Indonesia’s protected area network. Here, we document Keywords Conservation planning, Garrulax rufifrons the montane biodiversity of Gunung Slamet, an isolated slamatensis, Gunung Slamet, Hylobates moloch, Indonesia, volcano in Central Java, and provide evidence to support Java, species distribution models, threatened species its increased protection. During September–December , we surveyed multiple sites for birds, primates, terrestrial Supplementary material for this article is available at mammals, reptiles, amphibians and vegetation. Survey doi.org/./S methods included transects, camera traps and targeted searches at six sites, at altitudes of –, m. We used species distribution models for birds and mammals of con- servation concern to identify priority areas for protection. Introduction We recorded bird species ( globally threatened), n the face of the current global extinction crisis mammals (five globally threatened) and reptiles and I(Bradshaw et al., ; Ceballos et al., ), it is vital amphibians (two endemic). Our species distribution models to establish protected areas that can serve as biological reser- showed considerable cross-taxon congruence between im- voirs for species and ecological processes (Chape et al., ; ’ portant areas on Slamet s upper slopes, generally above Jenkins & Joppa, ; Le Saout et al., ; Venter et al., , m. Particularly important were records of the en- ). Governments, who are primarily responsible for creat- demic subspecies of the Endangered Javan laughingthrush ing and maintaining protected areas, report their progress by Garrulax rufifrons slamatensis, not recorded in the wild reference to Aichi Target of the Convention on Biological since , the Endangered Javan gibbon Hylobates moloch Diversity (CBD). However, with the majority of biodiversity and Javan surili Presbytis comata, and the Vulnerable Javan concentrated in the tropics, the pressure on developing lutung Trachypithecus auratus and Javan leopard Panthera nations across the equatorial belt to fulfil their CBD pardus melas. Recent forest loss has been modest, at least obligations is overwhelming (Chandra & Idrisova, ; km of continuous forest remain above m, and Harrop & Pritchard, ; Mallari et al., ; Jones et al., our surveys show that forest habitats are in good condition. ). Indonesia is a so-called megadiverse country, with par- However, the mountain is widely used by trappers and hun- ticularly high biological richness on the islands of Borneo, ters. Given its importance for biodiversity conservation, Sumatra and Java, and is considered one of the top three biodiversity hotspots globally because of high levels of both endemism and habitat loss (Mittermeier & Mittermeier, CHRISTIAN DEVENISH (Corresponding author, orcid.org/0000-0002-5249- ; Myers et al., ). Conserving biodiversity on Java 0844), OLIVER POOLE and STUART J. MARSDEN Department of Natural Sciences, is a particular challenge, with a human population of c. Manchester Metropolitan University, Chester Street, Manchester, M1 5GD, UK. E-mail [email protected] millionandapopulationdensityof. , people/km ACHMAD RIDHA JUNAID,ANDRIANSYAH,RIA SARYANTHI,FAJAR KAPRAWI and RICHARD (Badan Pusat Statistik, ). Biological endemism is concen- C. STANLEY* Burung Indonesia, Bogor, Indonesia trated on the island’s volcanic mountains, particularly in the S. (BAS) VAN BALEN Basilornis Consults, Arnhem, The Netherlands western part where the equatorial climate delivers high levels GANJAR CAHYO APRIANTO Faculty of Biology, Jenderal Soedirman University, of rain to the forests that cover the slopes of c. mountains Purwokerto, Indonesia (Whitten et al., ). Forest cover in the area declined by c. % ANDREW OWEN Chester Zoo, Chester, UK during – and then stabilized at c. , km .The N. J. COLLAR BirdLife International, Cambridge, UK remaining forests are highly fragmented and in need of pro- *Current address: University of Florida, Gainesville, USA tection (Higginbottom et al., ). Received June . Revision requested August . The mountains in western Java harbour numerous Accepted October . endemic and Sundaic species (Whitten et al., ). The This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, Downloadeddistribution, from https://www.cambridge.org/core and reproduction in any medium,. IP address: provided 170.106.35.229 the original work, on is 23 properly Sep 2021 cited. at 10:05:57, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/termsOryx, Page 1 of 10 © The Author(s),. https://doi.org/10.1017/S0030605320001222 2021. Published by Cambridge University Press on behalf of Fauna & Flora International doi:10.1017/S0030605320001222 2 C. Devenish et al. FIG. 1 Gunung Slamet, Central Java, with study sites, camera-trap locations, protected areas, forest cover in and forest loss since . Camp locations correspond to the survey sites, with transects not further than km from these points. easternmost of these mountains, Gunung Slamet, in western north and five flowing south, are currently managed by Central Java province, shares many taxa with the mountains the State Forest Management Agency (Perum Perhutani). further west but also possesses a degree of endemism of its The absence of formal protection for its biodiversity has own, such as a distinctive subspecies of the Javan laughing- left Gunung Slamet threatened by encroachment of hu- thrush Garrulax rufifrons slamatensis (Collar & van Balen, man activities (Setiawan et al., ). As part of a wider ). Its forests, like those in other mountain areas in initiative to document the biodiversity of western Java’s Central Java, transition from tropical in the west to mon- montane forests and to make recommendations for imple- soon in the east (Widhiono, ), and comprise lowland, menting a protected area status, we undertook field research montane and subalpine types (Soemarno & Girmansyah, on Gunung Slamet in , to assess its biological diversity ). The biological richness of Gunung Slamet was first and identify priority conservation areas. Here, we present described during Indonesia’s colonial period. Since , data on the distribution and relative abundance of key there have been studies of ferns (Praptosuwiryo, ), ter- faunal taxa, and on forest cover, forest loss and threats such mites (Pribadi et al., ), butterflies (Widhiono, ), bees as bird trapping. and wasps (Widhiono et al., ), birds (Widodo, , ), the Javan surili Presbytis comata (Setiawan et al., ), Javan gibbon Hylobates moloch (Setiawan et al., Study area ; Wahyuni & Nasution, ) and Javan leopard Panthera pardus melas (Wibisono et al., ). In the Gunung Slamet, an active stratovolcano in Purbalingga Indonesian Institute of Sciences published a compilation Regency in Central Java (Fig. ), is the second highest moun- of studies on the mountain’s geology, climatology and tain on Java, at , m (Maryanto et al., ). It receives an biodiversity (Maryanto et al., ). annual rainfall of c. , mm, which is among the highest When Indonesia’s protected area system underwent a precipitation levels in Indonesia. The rainy season is review in the early s, km of natural habitat at October–May/June, and the dry season July–September. ,–, m altitude on Gunung Slamet were recom- Daytime temperatures are – °C (Widhiono, ). The mended for protection as a nature reserve (MacKinnon, volcano last erupted in , and previously in , with ; MacKinnon et al., ; Nijman & Sözer, ; Sözer some forest burnt as a result. We worked at six study sites et al., ). However, no action was taken on this recom- on accessible trails leading up to the summit, at altitudes mendation and forest areas on the mountain, which serve of –, m(Table , Fig. ), avoiding the most heavily as hydrological protection forest for five rivers flowing used tourist trail and the site of a recent forest fire on the Oryx, Page 2 of 10 © The Author(s), 2021. Published by Cambridge University Press on behalf of Fauna & Flora International doi:10.1017/S0030605320001222 Downloaded from https://www.cambridge.org/core. IP address: 170.106.35.229, on 23 Sep 2021 at 10:05:57, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605320001222 Biological richness of Gunung Slamet, Java 3 eastern side of the mountain, and the restricted area sur- of cameras that had recorded mammal species, thus avoid- rounding the proposed Baturraden geothermal plant on ing some of the issues associated with identifying indepen- the western side. dent observation events (Wearn & Glover-Kapfer, ). Methods Identifying priority areas for conservation Biodiversity surveys To prioritize areas of particular significance for the protec- tion of biodiversity, we built species distribution models for We carried out fieldwork