Two species of introduced wasps are costing New Zealand's economy more than $130 million a year.
A German wasp on a thistle flower (file photo) Photo: 123RF
A study by the Department of Conservation and the Ministry for Primary Industries showed German and common wasps, which belong to the genus Vespula, have had huge economic impacts on farming, beekeeping, horticulture and forestry.
Department of Conservation scientist Eric Edwards said the loss of honey production was one of the major costs.
"When hives are placed down the back of the farm, wasps will come along, and they are interested in the honey and the bees themselves. They will eat both.
"They just worry the hives initially and so the bees spend time, energetic resources defending their hive. So that's the cost when bees could otherwise be doing pollination work."
Mr Edwards said wasps were one of the most damaging pests by harming native birds and insects and competing for food with native species.
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