LUDHIANA: Fish needs special care during winters, being a cold-blooded animal. Dr. Meera D. Ansal, Dean, College of Fisheries, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana said that during winters farmers shall keep the pond water depth up to 6 feet to provide enough space to the fish for hibernating in the warmer bottom zone. In shallow waters, the whole water column becomes cold, which affects the fish and can prove fatal. Regular addition of tube well water at dusk helps in keeping the surface water warm.