Symptoms

• Rats damage tender nuts and cause severe crop loss in many places.
• Shed tender nuts with characteristic holes can be located at the base of the affected palms (Image1).

Control Measures

• Fix G.I sheet bands, 40 cm wide around the trunk of palms at a height of 2 m from the ground to serve as mechanical barriers.
• Poison baiting using either single dose acute poisons like zinc phosphide or multiple dose anti blood coagulants like bromadiolone.
• Fumigate rat burrows in the field with aluminum phosphide tablets.
• Poison baiting with 0.005 per cent bromadiolone in coconut crown at 3-4 days intervals at the rate of 30 palms (bait points)/ha reduces the rat population and damage.
• Poison baiting at the ground level does not have much effect in controlling the rats since they seldom come to the ground. If there are residential buildings within the plantations, undertake rat control in both the places to check reinfestation.
• The best period to undertake the field operation to control the rat is late summer.
• Rat control is more effective, if measures are taken on a community and area basis.