The imagos are the destructive stage, they bore into the crown of the palm resulting in wedge shaped or \"V\" cuts in the fronds that unfurl. The beetle feeds on tissue juices. Some of the crushed fibre is pushed outside the entrance hole, where it indicates the insect’s presence. In India damage of inflorescence is also reported in severely infested areas which cause reduction in yield up to 10% (Nair, 1986). Ramachandran et al. (1963) has reported a loss in yield of 5.5 to 9.1% due to beetle attack. From artificially pruned leaf damage stimulation studies it was observed that damage to 50% fronds corresponds to leaf area reduction of 13% and decrease in nut yield by 23% (Young, 1974).

In oil palm O. rhinoceros bores into the base of cluster of spears, causing wedge shaped cuts in the unfolded fronds. In younger palms the effect of damage can be much more severe (Wood, 1968; 1976). Attack by adults may reduce yield and kill seedlings. They may provide entry points for lethal secondary attacks by the palm weevil Rhyncophorus or by other pathogens, in some countries (Bedford, 1980). Apart from coconut and African oil palm recorded host plants include the date palm and a variety of palms grown for ornamental purpose, including Roystonea regia, Livistona chinensis, Corypha umbraculifera and Raphia ruffia (Gressitt, 1953; Bedford,1980); also recorded are pine apple, sugarcane, pandanus and banana (Lever, 1979).

Biological: Biological control of the beetle is the most important component of the IPM package. The green Muscardine fungus Metarhizium anisopliae M. is a pathogen which kills the pest in conditions of low temperature and high humidity. The viral pathogen Baculovirus of Oryctes (OBV) is very effective and kills the grub in 15-20 days of infestation and it affects the longevity and fecundity of adult beetles. Insect predators are frequently observed in the natural breeding grounds of the beetle, which feed on the eggs and early instar larvae of the beetle. The important predators are Santalus parallelus Payk., Pheropsophus occipitalis Macleay, P. lissoderus, Chelisoches morio (Fab.) and species of Scarites, Harpalus and Agrypnus. As these predators help in the natural check of the pest population, conservation of the predator fauna is essential. Restricting and managing the breeding sites could check the proliferation of the pest. Proper disposal of breeding grounds and field sanitation are important steps in IPM of Oryctes. An effective trapping method with rotting castor cake slurry kept in mud pots has been developed for rhinoceros beetle. More details are available from Integrated Pest Management Information Package.

A list of control options from Controlling rhinoceros beetle in coconut: India an article in 'The Hindu' July 7 2005.