December 2015. A question of the distance that Oryctes rhinoceros can fly.
A member provided the following: From memory there is reference in Linsey Gressitt’s 1953 paper on the CRB (coconut rhinoceros beetle) in Palau. While working on the Rhino Beetle in Samoa 1969-1974, we had recovery of marked beetle flying at least 7 km. But the observations on colonization of small islets suggest that colonization across the sea was at least 20 km distance (but this is not direct evidence). An experiment was done on a suspended beetle and that it flew for 90 minutes – if you assume a speed of 10 kph this would put 20 km well within range. Of course this is direct flight – but observations suggest that they can orientate towards a light source from at least a kilometre.
Another member commented that there may not be enough consideration given to “normal behaviour of the insect in field conditions”. Where host plants are present, the insects behaviour will be completely different to where no hosts are present. Recently a paper was published on the red palm weevil concluding that the beetle could fly 50 km! The authors did not consider that the behaviour of the beetle is influenced by the density and state of the host plants.
A PDF was sent from Guam.
Flight of Oryctes
Flight Range CRB
Maximum range for a single straight-line flight is 4 km, as measured in a lab experiment with tethered beetles on a flight mill. However, from field observations it appears that natural flight is limited to a few hundred meters. In a mark-release-recapture experiment, Kamarudin and Washid measured a dispersal rate of 19m per day.
Hinckley, A. D. 1973. Ecology of the coconut rhinoceros beetle, Oryctes rhinoceros (Coleoptera: Dynastidae). Biotropica 5 (2):111–116.
“Beetles freshly fed on a palm were flown on a tether in the laboratory. Their flight duration averaged between 2 and 3 hours. Distances traveled were between 2 and 4 km. Beetles exhausted by such long flights were held in moist soil or wood for a day or two, after which they could again fly, although seldom longer than 30 minutes.”
Kamarudin, Norman and Mohd B. Washid. 2004. Immigration and activity of Oryctes rhinoceros within a small oil palm replanting area. Journal of Oil Palm Research 16 (2):64–77.
“Based on the capture, mark, release and recapture experiment using pheromone traps, the beetle’s ability to fly was estimated at about 19 m day-1 or more than 130 m in a week. The range covered was estimated at 10-23 m day-1. This suggests that the flight of beetles within a replanting area is quite limited because of the abundance of food and breeding sites.”
“Earlier reports have suggested the ability of the beetle to fly considerably long distances (Nirula, 1955; Hinckley, 1973). A distance recorded in the field was about 700 m (Monty, 1974). However, a laboratory experiment has indicated that the beetle can fly up to 2 to 4 km in 2 to 3 hr (Hinckley, 1973). Liau and Ahmad (1991) reported a flying distance of 140 m into a replanting area. This was in the case of migration to new breeding areas. But in this study, which was done within a replanting area, the beetle was noted to fly less (estimated around 19 m day-1, and about 133 m a week) (Table 5). These values may be below the actual flight potential as their flights were monitored using pheromone traps. However, the conducive environment, availability of food and abundant breeding sites in the replanting area logically play a role in the flight distance.”