ALAN (Artificial Light At Night) is a significant anthropogenic hazard can alter the circadian rhythm of animals. We have considered Macrobrachium lamarrei as the model organism to assess if ALAN can cause neurological stress in aquatic invertebrates and have effectively measured collective grooming behaviour in the prawn population. Animal grooming is recognised as an indicator of neuro-behavioural stress. Our primary goal is to assess the alteration in collective grooming activity in prawns due to ALAN exposure in a time kinetic manner.