Oxpeckers are more than just familiar birds on the backs of cattle and game – they are an important part of natural tick control systems. However, the wrong choice of tick remedy can place these beneficial birds at risk. In this Q&A, Dr Sunelle Strydom outlines which insecticide groups are safe to use in areas where oxpeckers occur, which products should be avoided, and how farmers can balance effective tick control with environmental responsibility.
Question: Which insecticide groups are safe to use in areas where oxpeckers occur?
Answer: There are two kinds of oxpeckers: Yellow billed oxpeckers and red-billed oxpeckers. Oxpeckers have a symbiotic relationship with cattle and game which benefits both bird and mammal. Oxpeckers use their beaks to comb through the animal’s fur for ticks.
Five groups of remedies are registered in South Africa for the chemical control of ticks, namely pyrethroids, amidines, organophos- phates, macrocyclic lactones and tick growth regulators (TGRs), also known as acarid growth regulators (AGRs). If AGRs are used on their own in a product or with amidines, the product is safe for mammals and birds, including oxpeckers. If amidine is used on its own in a product or with pyrethroids, it is safe for the environment, especially mammals and birds. Amidines break down rapidly.
Organophosphates are the most toxic dipping ingredient and should not be used at all in areas where oxpeckers occur. An injectable remedy containing macrocyclic lactones for the control of blue ticks, and also pour-ons containing AGR, are safe for oxpeckers.
Also read: Ask the Vet: Ticks outwit chemical remedies
Do the following to prevent resistance in ticks:
- Use a dip that has only one active ingredient; in combined remedies, resistance is developed to all groups concerned.
- If the dip is no longer effective, tick resistance tests and dip analyses can be done to determine whether there is really resistance, which tick species are resistant, at what dosage, to which groups or active ingredients and whether the dip was used at the right concentration.
- If resistance is confirmed, the farmer can switch to another group. If a pyrethroid was used, an amidine can now be used and if an amidine was used, a pyrethroid can now be used.
- If resistance to the new group occurs and is confirmed, the farmer can switch back to the previous group, because the resistance decrea ses with time. This concept is called reversion.
- Macrocyclic lactones may be used if there are resistant blue ticks.
- Remember; if the animals are kept completely tick-free by using acaricides, there will be no food for the oxpeckers. This can also accelerate the development of resistance.
Also read: Combat ticks in a natural way
Sources: Fletcher, W. A. 2001. A Guide to Practical Cattle Tick Control in Southern Africa. Oberem P., Odendaal D., Oberem P. T., Snyman M. G. S., Ludwig L. & Mynhardt H. 2006. Siektes en Parasiete van Beeste, Skape en Bokke in Suid-Afrika. Paarl Print (Paarl); www.ewt.org.za/species/oxpeckers.htm; www.bigfive.jl.co.za/compatibility.htm
