The use of salt licks by birds in Peninsular Malaysia

Abstract

Numerous wildlife species visit salt licks to consume soil (geophagy) or to drink water. Studies have mostly focused on salt lick use by mammals as they are easily identified owing to larger body size, predominance in using these resources, and predictable movement and behaviour, as well as several established hypotheses such as mineral supplementation. However, salt licks are also crucial to some birds. The interest in and documentation of avifaunal geophagy at salt licks have increased in recent years. However, few studies have investigated this phenomenon in Southeast Asia. We used camera traps to document bird species richness, diversity and encounter rates at 20 salt licks (nine natural and 11 artificial) within three reserves (the Royal Belum State Park, Perak and Krau Wildlife Reserve, Pahang, both primary forest, and secondary forest in Tembat Forest Reserve) in Peninsular Malaysia. We compared parameters between the two types of salt lick (natural and artificial) and two types of habitats (primary and secondary forest). We found that salt licks were used by 24 bird species, including pheasants, hornbills, rails, herons, doves, cuckoos, pittas, bulbuls, flycatchers, and estrildid finches. Raptors did not exhibit geophagous behaviour, except for the Brown Wood-Owl (Strix leptogrammica). Most salt lick users were resident carnivores and insectivores. The Asian Emerald Dove (Chalcophaps indica) and Red Junglefowl (Gallus gallus) were the most frequent birds at salt licks. Avian species richness in primary forests was similar for both types of salt licks, but species diversity was higher at natural salt licks. Meanwhile, species diversity at artificial salt licks was similar by habitat type, but bird’s species richness was significantly higher at primary forest artificial salt licks than at secondary forest artificial licks. Encounter rates of birds at artificial salt licks were higher than natural salt licks in primary forests. Furthermore, bird encounter rates at secondary forest artificial salt licks were higher than at primary forest artificial licks. We suggest that artificial salt licks can be used to enrich degraded forests since they serve a role similar to that of natural salt licks and can attract birds and other animals. This information is crucial to conservation and biodiversity management planning for protected forests, particularly secondary and degraded forests.