The stink bug season, which runs from September to May in South Africa, results in millions of rands’ worth of crop losses for the macadamia industry every year. Investigating a revolutionary approach to controlling this pest is Tongaat farmer Tanya Goble, who is currently trialling the use of guinea fowl in their 135 hectares of macadamia nut orchards.
Tanya, wife to the 2015 Kwanalu Young Farmer of the Year and Toyota SA/Agri SA National Young Farmer of the Year winner, Anthony Goble, took her love for fowls and turned it into a promising solution for controlling the stink bug population and reducing the need for continual spraying in their orchards. Currently most macadamia farmers use the scout and spray method; a year-round stringent process that is both time-consuming and expensive.
According to a fact sheet published by Macadamias South Africa (SAMAC) in 2016, the chemicals used in the spraying process is indiscriminate and long lasting. The neo nicotinides found in these products have been banned in the EU since 2015 due to concerns over the effect on essential pollinators; specifically bees. SAMAC also reported that chemical control accounts for 16 percent of the overall production cost; the second highest after labour.
“Timing, scouting and application for these pests is vital otherwise they won’t be picked up in time. With guinea fowl foraging all the time, I’m hoping to keep the stinkbug numbers low so that we don’t have to spray as much,” said Goble.
The idea originated from keeping a few guinea fowls as pets and subsequent research into their diet.
“Through my research, I learnt that 90 percent of a guinea fowl’s diet consists of bugs, but which other bugs in a South African context remains to be seen. I discovered that stink bugs were on the list of pests they eat and so two years ago, I decided to start breeding guinea fowls to test their use as a natural pest control in our macadamia nut orchards,” said Goble.
Starting with a flock of 50 birds, Goble released them into their 135 hectare macadamia orchard in February 2022. Already, she has discovered some insightful areas of improvement.
“The home flock naturally only roam around 20 hectares. There simply aren’t enough guinea fowl yet to notice a real difference within this sample area and many more are needed. The age which they are released is also important as they have many natural predators when they are too small, so it a very much a learning process at the moment,” said Goble.
She is currently incubating a further 200 guinea fowl, with hopes of releasing them when they are six months old. When released, she will be able to assess whether they would be a useful control method for other pests as well, such as thrips and macadamia nut borer within macadamia orchards.
Not limiting themselves to their own farming operations, the Gobles are known for their progressive attitude towards agriculture, one of the factors contributing to Anthony being named 2015 Kwanalu Young Farmer of the Year and Toyota SA/Agri SA National Young Farmer of the Year.
“During the competition evaluation on all aspects of the his thriving sugarcane, banana, macadamia nut and seed cane business, he stood out for his involvement and approach to economic development and land reform,” said Kwanalu CEO, Sandy La Marque.
Tanya is no different and hopes to have a broader impact should the use of guinea fowl in pest control prove to be effective.
“If all goes well in the next stages of release, I hope to start a breeding and incubation programme to benefit other farmers in their orchards,” said Goble.
“Kwanalu and its members take pride in the holistic perspectives and sensitivity towards environmental matters within KwaZulu-Natal’s agricultural sector. It is through investigations like Tanya’s, that agriculture is able to find novel ways to reduce crop losses while peacefully co-existing within existing biodiverse ecosystems,” said La Marque.