Environmental Conditions and Vigilance Behaviour in the Smooth-coated Otter, Lutrogale perspicillata

Abstract

Vigilance is an ecologically important behaviour that acts as a defence mechanism against threats such as predators, competitors, and environmental pressures. Being vigilant can place energetic constraints on an individual, as conducting other behaviours such as grooming can be limited. The smooth-coated otter is a vulnerable species, and understanding baseline behaviour, such as vigilance, and stressor effects can be a crucial step in implementing any conservation strategies. However, literature on this charismatic species is relatively sparse, with the majority of research covering prey items, habitat use and extent of occurrence. Using camera trap footage along with historical climate datasets, the current study assessed various aspects of vigilance behaviour of the smooth-coated otter. These aspects include how long individuals dedicated to being vigilant, what they prioritised being vigilant over, and how intense their vigilance efforts were. Variables that are expected to change with global climate change such as temperature, and to an extent, air pressure, were associated with increases in vigilance duration. Wind speeds, which are also expected to be affected by climate change, along with increasing numbers of conspecifics, were linked to increased intensity possibly highlighting that increasing ambient movement results in more frequent head rotations. When vigilance is ineffectual however, such during periods of higher rainfall, cloud cover or at night, intensity decreases, and gazing towards conspecifics increases - possibly to reaffirm where safety lies when threats cannot be adequately monitored.