First release of a captured Sumatran striped rabbit Nesolagus netscheri (Schlegel, 1880) into the wild

The Sumatran striped rabbit Nesolagus netscheri (Schlegel, 1880) is a rare, endemic mammal found only in mainland Sumatra, Indonesia. In late September 2021, the Nature Conservation Agency of Bengkulu province received two young N. netscheri individuals caught from a village in Bengkulu province, Sumatra, Indonesia. After four months in captivity, in early February 2022, the Nature Conservation Agency of Bengkulu Province decided to release the rabbits in the general area where they had been collected. This is the first known instance of a release of N. netscheri into the wild after a period of captivity.


Introduction
The Sumatran striped rabbit Nesolagus netscheri is one of the rarest lagomorph species and is endemic only to Sumatra, Indonesia (Schai-Braun & Hacklander 2016). This species is classified as Data Deficient by IUCN, owing to a lack of data on which to base estimates of population size, density, and distribution (McCarthy et al. 2019). The species is thought to be found primarily at elevations above 600 m in montane and sub-montane primary habitat of Bukit Barisan mountain range in western Sumatra, from Leuser National Park in the north, to the Bukit Barisan Selatan National Park in the south (Flux 1990;Setiawan et al. 2019). The Sumatran striped rabbit is presumed to be strongly forest dependent, with the only records in the agricultural landscapes reported around the border of the forest, or in newly clear areas from which they have been displaced (McCarthy et al. 2012;Setiawan et al. 2018).
The N. netscheri was a species protected by Indonesian law since 1972 (Noerdjito & Maryanto 2001), and this species still recently protected by new updated Indonesian law (Ministry of Environment and Forestry 2018). However, conservation awareness was very limited, and it is no wonder if N. netscheri still found offers for sale on social media (Setiawan et al. 2019;Supardi 2021). McCarthy et al. (2019) proposed one of the conservation actions of N. netscheri is to conduct a targeted study of the species, with a methodology designed specifically to maximize its detection.
Due to its rarity, we report the incidental capture of two young N. netscheri, and their subsequent release into the wild after four months in captivity.

Methods
In late September 2021, the Nature Conservation Agency of Bengkulu Province (Balai Konservasi Sumber Daya Alam Provinsi Bengkulu or BKSDA Bengkulu) received two young N. netscheri from local people. It is presumed that the rabbits were roughly one month of age, and they were both males. The rabbits were collected by local people in a garden in a village at Curup Selatan Subdistrict (specific location is not mentioned because of rarity and endemicity of the species), Rejang Lebong District, Bengkulu Province. Local people who had obtained the rabbits did not recognize that the animals were officially protected by Indonesian law. They gave the rabbits to the Nature Conservation Agency of Bengkulu Province after they were informed of the species's identity and national regulations protecting the species. After four months in captivity at the Nature Conservation Agency (from late September 2021 to early February 2022), it was decided that the individuals should be released back into the wild. The release went smoothly with attended by a small number of people (less than 10 people) from representation of the Nature Conservation Agency of Bengkulu Province, Forest Management Unit Protected of Bukit Balai Rejang and local people. The location of release is the similar area where N. netscheri was first time caught by local people. There is no specific monitoring program on N. netscheri, but there is a regular monitoring regarding patrol on conservation areas (that also detected the presence of N. netscheri).

Results and Discussion
The two captured individuals of N. netscheri had darker colour, indicating that these individuals were young (Fig. 1). Nesolagus netscheri is a distinctive mammal in Sumatra, and easily identifiable by its morphological characters and size (Schai-Braun & Hacklander 2016). This species has a conspicuous dark brown or wide black stripes on a yellowish-gray background that become rusty brown toward the rear, the ventral fur and the chin; having black ears; and the inside of the legs are whitish, with young individuals displaying a slightly darker coloration (Flux 1990;Schai-Braun & Hackländer 2016;Setiawan et al. 2019).
The condition of two young N. netscheri are very in health condition. They are very active in the movement, particularly at night. Unfortunately, there are none of any samples collected (eg. tissue, feces or other), The keeper try to reduce any disturbance to avoid stress to the rabbits. The captive N. netscheri were fed some vegetables during quarantine, but Water spinach Ipomoea aquatic was the favourite plant ate by the captive individuals. Flux (1991) summarized possible plants and food accepted by N. netscheri, including Cyrtandra sp., Aracea sp, to cooked Rice Oryza sativa, young Maize Zea mays, bread, ripe Bananas Musa sp., Pineapple Ananas comosus, Beans, Radishes Raphanus raphanistrum, Carrots Daucus carota and young shoots (Oak Quercus sp., Elm Ulmus sp. and Beech Fagus sp.); and few plants were eaten reluctantly such as sweet potato Ipomoea batatas, Jussieua suffruticosa, Knotweed Polygonum sp., Spiderwort Tradescantia sp., Elatostemma sp., Hemigraphis colorata and Clover Trifolium sp. Among the plants, the Cyrtandra sp. was considered as important diet of N. netscheri in the wild (Setiawan et al. 2018).  The N. netscheri was in captivity for four months (from late September 2021 to early February 2022). As the young rabbits continued to grow and become more active, the Nature Conservation Agency of Bengkulu Province became afraid that the rabbits would escape, so the captive individuals were released into the wild in early February 2022 (Fig. 2). The successful release of the individuals after confiscation, is the success story of conservation actions conducted by government authority for this little known endemic mammal in Sumatra. This case reflect N. netscheri is adaptable to various plants and food if the species keep with great care. Furthermore, working close to local people could be potentially duplicated in the other conservation region areas in this country. Public conservation awareness is a key to support effective conservation efforts, particularly in forest large areas with limited staff in many conservation areas in Indonesia.