Ants protect conifer seedlings from feeding damage by the pine weevil Hylobius abietis
Version of Record online: 22 NOV 2012
© 2012 The Royal Entomological Society
Agricultural and Forest Entomology
Volume 15, Issue 1, pages 98–105, February 2013
How to Cite
Maňák, V., Nordenhem, H., Björklund, N., Lenoir, L. and Nordlander, G. (2013), Ants protect conifer seedlings from feeding damage by the pine weevil Hylobius abietis. Agricultural and Forest Entomology, 15: 98–105. doi: 10.1111/j.1461-9563.2012.00597.x
- Issue online: 22 JAN 2013
- Version of Record online: 22 NOV 2012
- Accepted 22 September 2012
- biological control;
- Formica rufa group;
- insect herbivores;
- integrated pest management (IPM);
- seedling damage;
- trait-mediated interactions;
- trophic cascades
- 1Ants that protect food resources on plants may prey on (or deter) herbivores and thereby reduce damage. Red wood ants (of the Formica rufa group) are dominant ants in boreal forests of Eurasia and affect the local abundance of several herbivorous species.
- 2The pine weevil Hylobius abietis (L.) is a herbivore that causes severe damage by feeding on the bark of coniferous seedlings within areas of forest regeneration.
- 3We investigated whether ants can protect conifer seedlings from pine weevil feeding. In a manipulative experiment, ants were attracted to sugar baits attached to spruce seedlings and the damage caused by pine weevils was compared with control seedlings without ant-baits.
- 4The feeding-scar area was approximately one-third lower on the seedlings with ant-baits compared with the controls. Besides red wood ants, Myrmica ants were also attracted in high numbers to the ant baits and the relative effects of these species are discussed.
- 5The results obtained in the present study support the trophic cascade hypothesis (i.e. damage to herbivores is suppressed in the presence of predators). The decreased pine weevil feeding on the baited seedlings was probably a result of nonconsumptive interactions [i.e. the presence of (or harassment by) ants distracting pine weevils from feeding].
- 6Understanding the role of ants may have important implications for future strategies aiming to control pine weevil damage. For example, maintaining suitable conditions for ants after harvesting stands may be an environmentally friendly but currently unexploited method of for decreasing weevil damage.