Cockroaches and ants big winners of climate change
Creepy crawlies we love to hate are marching south as climate change warms temperatures and lengthens breeding seasons. Cockroaches, Argentine ants, and oversized ladybirds were among bugs getting a foothold in regions where they were previously rare. Spring is the time of year when everybody notices the environment come alive with bugs, but each year the rising average temperatures mean insect activity is starting earlier and finishing later. South Island centres such as Nelson and Christchurch have experienced pest problems in recent years they have never had to deal with before. READ MORE: * How to kick flies, ants, wasps and fleas out of your house this summer * 'Hideous' ant infestation plagues north Auckland homes * The battle against bugs: Its time to end chemical warfare Pest Management Association of New Zealand vice president Paul Craddock is an entomologist with a good handle on how some of the more bothersome insects have expanded their territories. He said climate change was giving insects longer breeding seasons, which was dramatically affecting numbers and viable habitats. Insects, being cold-blooded, are very dependent on the overall climate, will have good seasons and bad seasons depending on the weather. What were getting is longer, warmer summers and autumn and spring is generally a lot warmer. They start a bit earlier, and they last a bit longer in summer ... and it also changes the potential area they can exist in around the country. Craddock said some of these pests may have been in southern areas before, but more temperate seasons were allowing them to flourish. New Zealand is home to many species of cockroach, some of which are becoming much more commonly found in households in the lower and central North Island, and upper South Island. They have become a nuisance in places such as Wairarapa and the Hutt Valley, although Wellington city has largely been spared. Another good example of pest expansion is Darwins ant, which has become a big problem in the South Island. Its slowly spreading its range and climate change is helping that along, Craddock said. Sandra Speirs, the Bug Lady, deals with pest insects in the Tasman region and has noticed a huge increase in cockroaches and ants around the Nelson area. It increasingly gets worse each year. When she started in the pest control business 12 years ago there were virtually no cockroaches and very few ants. Now ants is the most, then cockroaches, then spiders and then flies. Another bug that has burst on to the scene is the invasive Harlequin ladybird . It was first discovered in Auckland in 2016 and is now moving down the country. It is much bigger than the native variety most people are used to, and could well end up displacing the local species. Dawn Hendrikse runs a pest management firm in Christchurch and said ants had become a serious problem in Canterbury. Its been a long term thing, where theyve slowly but surely spread across the country. Over the last 10 years our ant work has increased quite significantly and probably in the last five years its been even quicker still. Hendrikse said black house ants and white-footed ants were the most common with Argentine and Darwin species starting to appear more recently. It seems as though cockroaches do not yet have a firm hold in the southern parts of the country, but recently have been found as far south as Timaru .