To enlarge a photo please click it. Last dayToday, Friday 25 September 2019, is the final day of a week of worldwide school climate protest. It's also the main New Zealand strike day. Earlier, I joined thousands of school pupils and others outside Parliament in Wellington city. Official estimate 40,000. I was answering a call to grandparents to stand behind the young protestors. Will these massive young people strikes in countries all over the globe have any real affect on politicians and powerbrokers? In sceptical mood I think 'No'. In hopeful mood I think 'Yes'. 6th mass extinctionOne of the things students have been protesting about is what many scientists are calling the 6th mass extinction – the die-off of animal species in unprecedented numbers. Insects is one of the groups. In my post for Friday 5 May, this year, just after the UN's 'extinction report' came out, I noted this: '“The world’s insects are hurtling down the path to extinction, threatening a catastrophic collapse of nature’s ecosystems,” says UN Environment biodiversity expert Marieta Sakalian. “We urgently need to take action on many fronts to stem this decline.”' Then I noted that 'pollinators' are particularly at risk, and of the pollinators, bumblebees are in world wide decline. Look for instance at these two sentences from An Annual Review of Entomology February 2008. 'Declines in bumble bee species in the past 60 years are well documented in Europe, where they are driven primarily by habitat loss and declines in floral abundance and diversity resulting from agricultural intensification.' 'In North America, catastrophic declines of some bumble bee species since the 1990s are probably attributable to the accidental introduction of a nonnative parasite from Europe, a result of global trade in domesticated bumble bee colonies used for pollination of greenhouse crops.' In my gardenIn my garden there are no honey bees and hardly any bumblebees. I wanted to know more about bumblebees. What are they really like? Are they good pollinators? So I went to the New Zealand Bumblebee Conservation Trust website and copied this text. I hope you find it interesting. 'A single bumblebee can do 50 times the work of a honeybee and carries a bigger payload of pollen. They will also pollinate flowers honeybees can’t. For example honeybees aren’t boisterous enough to dislodge pollen from tomato flowers whereas bumblebees will vigorously buzz the flower and bee rewarded with showers of pollen falling on their bodies. This technique is known as ‘buzz pollination’. In a glasshouse one bumble bee can pollinate up to 450 flowers per hour. Bumblebees carry up to 90% of their body weight in food and the level of activity required to fly is so great they are only ever 40 minutes away from starvation. They can reach ground speeds up to 54 kms per hour. Bumble bees are fantastic navigators and can remember landmarks to help steer them back to the hive. They will forage out to about 1-1.5 km and equally so are also happy in confined areas. They will work from daylight to dark in rainy weather and will be out and about at temperatures just above freezing. They have a unique body temperature control system which keeps them warm when it’s cold and cool in the heat. The females (queens and workers) have a sting and only sting if disturbed or handled roughly. Generally they are not aggressive at all. Bumblebees have smelly feet and will leave a smelly footprint to show they have been to a flower. Other bees will be able to tell if the flower has already been looted! All flowers replenish their pollen and nectar at different speeds e.g. comfrey takes around 40-60 minutes to refill where as borage takes two hours. Other flowers can take days. Once the flower is full again the smelly footprint wears off giving the green light for whoever visits next. Bumblebees only store a few days worth of food so are more vulnerable to food shortages.' Future
Bumble bees are vital pollinators and I want to help them stay around. That's for the future. So when I have something practical to report I'll write again. ########## John McInnes Friday 27 September 2019 Reference: An Annual Review of Entomology 2008 in Research Gate net New Zealand Bumblebee Conservation Trust -------------------------------------------------------------------------------------------------------------------------------
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