Rhinoceros Beetle – Why is it important?

The coconut rhinoceros beetle recently arrived in Solomon Islands and is causing serious damage to coconut palms on Guadalcanal, Savo, North Malaita and Ngela, and to oil palms on Guadalcanal. Many people are asking, “Why is it important?”

Everyone knows coconuts are the most important crop in the country but few know just how important. Here are some facts take

n from a 2014 World Bank, DFAT, IFAD report:

1. Solomon Islands has about 40,000 families or 80% of the population, living in the rual areas. Most of these families grow coconuts for many  different uses.

2. Most Solomon Islands families, in villages and in towns, use coconuts for cooking, eating and drinking every day. This is estimated at nearly 200,000 nuts EVERY DAY for food.

3. 2 – 3 times this amount of nuts are used daily to make copra which is the main source of income in villages. That is 4 – 600,000 nuts every day.

4. The value of copra exports is as follows:

   1. SI$110 – 150 million per year as raw copra.

   2. SI$40 – 50 million per year as copra and virgin oil.

   3. SI$20 – 40 million per year as copra byproducts.

   4. SI$300 – 400 million per year in total = US$40 – 50 million.

Remember most of this income goes directly into the village economy. That is up to SI$10,000 per rural houshold per year from copra alone. The true value of coconuts is even higher as coconuts also provide income from domestic sales or local use of coconut products.

1. When the coconut rhinoceros beetle arrived in Samoa, Tonga and Fiji 100 years ago more than half the coconut palms were killed and the yield in the remaining palms was severely reduced.

2. Similar effects can be seen in Honiara and North Guadalcanal today.

As the beetle spreads village people will have to make some hard decsions. They will have to choose between making copra or eating the nuts, there is unlikely to be enugh nuts for both. Should they feed their family with free healthy food or should they make copra to pay school fees, food and other things.

If families choose to make copra then they will have to buy more food from the shops; this is likely to be the cheapest, but less healthy, food available. Consuption of soft drinks will go up and soon after so will the number of diabetes cases.

Other palms are also affected including oil palm, betel nut, sago and royal palms. Attacks on these will have a range of effects but the most serious will be on oil palm as this provide livelihoods for thousands of people and SI$150 - 200 million in export earnings.

As mentioned in an earlier news story everyone can help to control the pest by cleaning up and destroying the breeding sites as the beetles love piles of rotten vegetation especially dead, decaying, palms. Around town and anywhere else, dead palms should be cut down and destroyed as they are perfect breeding places. Palms which are not yet dead (they still have a growing spike) might recover and perhaps they can be left in place in case they do recover, but as soon as they are clearly dead they too should be destroyed.

Photo: Fiji c. 1960. The effect of coconut rhinoceros beetle attack. G.O. Bedford (2013) Annu Rev Entomol 58: 353–72