Bees waking up earlier due to climate change risk falling out of sync with plants

Bees in Britain waking up weeks earlier due to warming climate may threaten the pollination of crops such as apples and pears, according to a new study. For every degree Celsius rise in temperature due to climate change , wild bees, including bumblebees, are emerging 6.5 days earlier on average from their nests, the research, published in the journal Ecology and Evolution, found. Bees waking up earlier in spring may lead to them losing sync with the plants they depend on and having less food to consume, warn scientists, including those from the University of Reading in the UK. This could lead to the bees not having enough energy to pollinate crops effectively, or missing crop blossom completely, they say. ‘Rising temperatures are making life tougher for bees. Warmer conditions mean bees emerge from hibernation earlier, but there may not be enough food to provide energy for them when they start buzzing about,’ study co-author Chris Wyver explained. Scientists have previously found that it is vital for bees to match their waking-up dates with the exact time of plant flowering so that they find pollen and nectar that increase their chances of survival and produce offspring. ‘A mismatch means bees cannot pollinate effectively,’ Dr Wyver said. Less-effective natural pollination could lead to farmers needing managed honeybees, which could mean greater costs that may be passed on to consumers. ‘We could see even more expensive apples, pears and vegetables in supermarkets as a result,’ Dr Wyver said. In the research, scientists examined 88 different species of wild bees over a period of 40 years, analysing more than 350,000 individual recordings. They found shifts in the emergence dates of bees in relation to temperature changes linked to the climate crisis. On average the 88 species are emerging 4 days earlier per decade, according to the study. Researchers say spring is likely to continue to start earlier with the UK Met Office predicting winters to be between 1 and 4.5°C warmer and up to 30 per cent wetter by 2070. This may lead to bees continuing to become active earlier in the year, the study warned. Early emergence of bees in spring is expected to have a greater effect on plants heavily dependent on pollination, such as apple trees. To better track plant flowering and its links to climate change, researchers have set up a project named FruitWatch to encourage people to report when fruit trees in parks or their gardens start to flower.