Native bees are also facing a novel pandemic

July 9, 2020 11:35am IST Source

    There is growing evidence that another 'pandemic' has been infecting bees around the world for the past two decades, and is spreading a fungal pathogen known as Nosema . It's been documented across Europe, Canada and even in Kenya. This infection has almost exclusively been recorded in the European honeybee, the recognizable commercial pollinator.

The study published in Plos Pathogens reveals that almost nothing is known about the impact of this pathogen on native, solitary bees, which make up the majority of the approximately 20,000 bee species on the planet. Not only are native bees incredibly important as pollinators in their local ecosystems, as honeybees are not generally found in these places, but they also contribute to the pollination of agricultural crops.

Bee populations and specifically honeybee hives, around the world, have been declining in the past two decades due to colony collapse disorder. While there is no singular cause behind this phenomenon, bees' and their colonies' health are affected by what's known as the four P's: pests, pathogens, poor nutrition, and pesticides. Nosema is a fungal pathogen, a type of Microsporidia, or a spore-forming single-celled parasite.

It survives by infecting the guts of bees, where it germinates, infects the host's cell, reproduces, and ruptures the host cell to release its spores. While being passed through the digestive tract, these spores can infect other cells in the bee's body, sickening the bee and contaminating flowers, pollen, and hives along the way. Some strains of Nosema even lower sperm count and mutilate the male genitalia of bumblebees, reducing their reproductive success.

The study authors say it's crucial for scientists to better understand how these Nosema strains are traveling the globe and affecting native, solitary bees, as they could lead to further bee pandemics and contribute to colony collapse.