Faunal survey in Kerala’s Vazhachal adds 26 species to checklist of wildlife division in Western Ghats

An intensive faunal survey in the Vazhachal wildlife division in Thrissur, Kerala, has documented 26 species previously unrecorded from the area, highlighting the rich biodiversity of the key corridor in the Western Ghats.

The survey was conducted by the Kerala Forest department in association with the Travancore Nature History Society (TNHS) from February 26 to March 1.

Around 50 experts and delegates, along with an equal number of forest frontline staff, participated in the exercise. Fourteen field camps were set up across diverse habitats ranging from dry and moist deciduous forests to evergreen systems, covering elevations from the Malakkappara-High Forest borders to the Chalakudy landscape. The researchers adopted a multi-taxa methodology to document butterflies, birds, odonates, cicadas, spiders, ants and other faunal groups.

Butterfly diversity was particularly striking, with 175 species recorded during the survey, including 13 new additions to the Vazhachal wildlife division’s checklist. Among the notable sightings were Red-spot Duke, Acute Sunbeam, Hampson’s Hedge Blue, White-tipped Lineblue, Common Tinsel and Sahyadri Purple-spotted Flitter. Seasonal migration of Dark Cerulean butterflies and large congregations of Blue Tigers, Dark Blue Tigers and Crows were also observed to indicate an active seasonal movement even during the dry phase.

The team also recorded 187 species of birds, including 10 additions. The significant sightings included Black Stork, Black-headed Ibis, Black Baza, Greater Spotted Eagle, Large Hawk-Cuckoo, White-bellied Sholakili and Tree Pipit. Other notable observations were Grey-headed Fish Eagle, Lesser Fish Eagle, Sri Lanka Frogmouth, White-rumped Shama, Grey-bellied Cuckoo and Blue-eared Kingfisher.

Besides, the researchers reported healthy populations of Great Hornbill, Malabar Grey Hornbill and Malabar Pied Hornbill. Their presence emphasises the structural integrity of the forest canopy and fruiting tree networks within the division.

Despite being a dry season, the survey documented 45 species of odonates, including three additions, viz., Trithemis pallidinervis,Lestes elatus and Caconeura risi. The team also recorded 30 species of ants, 33 species of spiders and six species of cicadas, reflecting substantial arthropod diversity.

Wildlife sightings

Wildlife sightings during the survey included tigers, leopards, herds of elephant, stripe-necked mongoose and the endangered lion-tailed macaque.

Vazhachal Divisional Forest Officer Suresh Babu I.S., who led the exercise, termed the addition of the new species, particularly during a dry-season survey, as a remarkable achievement. The findings, he added, reaffirms ecological significance of the Vazhachal landscape as one of the most biologically significant forest divisions in Kerala.

TNHS research associate Kalesh Sadasivan points out that the scale of additions recorded is an indication of how biologically under-documented the region is. The habitat heterogeneity across elevation gradients supports substantial faunal turnover.

A structured post-monsoon survey is likely to reveal even greater diversity, particularly among butterflies and odonates, he added.