It is essential that grain farmers start implementing precautionary measures as soon as possible, said Dr Gerhard Verdoorn, CropLife SA’s operations and stewardship manager.
Registered rodenticides listed in CropLife’s gerbil management plan must be placed in bait stations or in gerbil burrows, he cautioned. Scattering rodenticides on the surface of the soil is not only illegal, but ineffective.
“We also encourage grain farmers to create an environment conducive to owls and diurnal raptors, such as erecting owl boxes. These birds are valuable assets in gerbil control,” said Verdoorn.
“It’s also vital that producers regularly check hedgerows for burrows and gerbil droppings.”
Gerbils are found in South Africa’s grasslands, savannah, Karoo and fynbos biomes, according to Verdoorn.
“The animals start digging out seed just after planting, but the most damage is caused when seeds are germinating. This is probably due to seed being soft and more palatable than when newly planted,” he said.
Reports of 40 000 gerbils per hectares were not uncommon, said Verdoorn.