Estimating the abundance of Nepal's largest population of tigers Panthera tigris

Abstract

Information on the abundance of tigers Panthera tigris is essential for effective conservation of the species. The main aim of this study was to determine the status of tigers in Chitwan National Park, Nepal, including the Churia hills, using a camera-trap based mark-recapture abundance estimate. Camera traps (n 5 310) were placed in an area of 1,261 km 2 from 20 January to 22 March 2010. The study area was divided into three blocks and each block was trapped for 19-21 days, with a total effort of 3,582 man-days, 170 elephant-days and 4,793 camera-trap nights. The effectively camera-trapped area was 2,596 km 2 . Camera stations were located 1.5-2 km apart. Sixty-two tigers (age > 1.5 years), comprising 15 males, 41 females and six of unidentified sex, were identified from 344 photographs. The heterogeneity model Mh (jackknife) was the best fit for the capture history data. A capture probability (P) of 0.05 was obtained, generating a population estimate (N) of 125 ± SE 21.8 tigers. The density of tigers in the area, including Churia and Barandabhar (buffer zone forest linked with mid hill forest), was estimated to be 4.5 ± SE 0.35 tigers per 100 km 2 , using a Bayesian spatially explicit capture-recapture model in SPACECAP. Our study showed the use of Churia by tigers and we therefore conclude that the Chitwan tiger population serves as a source to maintain tiger occupancy of the larger landscape that comprises Chitwan National Park, Parsa Wildlife Reserve, Barandabhar buffer zone, Someswor forest in Nepal and Valmiki Tiger Reserve in India.

Diet of Bengal Tigers (Panthera tigris tigris) in Chitwan National Park, Nepal

“…1) and holds the largest population of tigers in the country (Karki et al 2013). The park is adjacent to Parsa Wildlife Reserve (PWR) in the East and the Barandabhar corridor forests and Himalayan Mahabharat Mountains in the north.…”

Density and carrying capacity in the forgotten tigerland: Tigers in the understudied Nepalese Churia

“…The inter-trap distance between 2 consecutive stations ranged from a minimum of 0.6 km to a maximum of 3.52 km, with an average distance of 1.56 km (SE 0.09). To maximize capture probabilities, we positioned camera traps along river banks (dry and wet, n = 119), animal and human trails (n = 29), and fire-lines (n = 10), where the presence of car-nivore signs was high and because predators are known to follow these routes (Karanth & Nichols 2002;Karki et al 2013). Due to a limited number of cameras, we followed the 4th design protocol of Karanth and Nichols (2002) and rotated camera traps from block to block sequentially to cover the area of interest.…”

“…The first systematic tiger census carried out in Chitwan National Park (CNP) did not sample the Churia habitat (Karki et al 2009). Following that, Karki et al (2013), recorded a few individual tigers within the Churia in CNP during a camera survey. However, whether tigers frequented the extensive Churia hills was still unknown.…”

Mitigating Human-Tiger Conflict: An Assessment of Compensation Payments and Tiger Removals in Chitwan National Park, Nepal

“…Harboring the largest (125) and increasing tiger population of Nepal, CNP serves as the source population for surrounding landscapes of Nepal and India [15]. In 2004, as many as 19 people were reported killed by tigers in and around CNP [9], indicating that the impact of HTC is substantial.…”