Warming winters in New Zealand bring insect pests, smaller fruit, and carbon loss from forests

A new article from The Conversation explains how warming winters in New Zealand are already changing forests, farms, and pest patterns. Researchers found that kauri trees in Auckland are growing through winter, but extra respiration means forests are losing more carbon than they store. Flowering times have shifted and fruit biomass has dropped in central North Island forests since the 1950s, hurting native birds like kereru. Warmer winters are also allowing more insect pests to survive the cold season. Wasp colonies are staying active year round, and species like Queensland fruit fly and cattle ticks are expanding their ranges. For horticulture, crops like apples, kiwifruit, and avocados need cold nights to trigger flowering, so warmer winters threaten fruit quality and yields. The article notes that alpine birds like rock wren and kea face greater extinction risk as invasive mammals move to higher elevations.