Mite-hunting arachnids could help Bermuda’s bees
The public have been asked to look out for tiny bugs that could potentially help to protect Bermuda’s birds and bees.
Mark Outerbridge, a wildlife ecologist, said in the summer edition of the Department of Environment and Natural Resource’s EnviroTalk newsletter that minuscule pseudoscorpions could be valuable tools for conservationists.
Dr Outerbridge said pseudoscorpions, also known as false scorpions, could feed on mites that damage the island’s honey bee and bluebird populations.
However, he said there was a lack of information about which pseudoscorpions lived on the island.
“There are 27 species recorded from the British isles and over 350 from North America but, to date, only one species has been described from Bermuda, Pachyolpium atlanticum, which lives on the coast in the intertidal zone,” he noted.
“I find the local paucity surprising given how long Bermuda has been colonised by humans and how frequently we have traded and continue to trade with both North America and the UK.”
Dr Outerbridge added: “Perhaps these secretive arachnids are just understudied rather than under-represented on Bermuda.”
Pseudoscorpions are arachnids related to spiders, mites and true scorpions, but they average only a few millimetres in length and are known to live outdoors and indoors.
While the animals have tiny pincers, called pedipalps, which makes them resemble true scorpions, they do not have a stinger and are harmless to humans, instead hunting smaller insects and mites.
Dr Outerbridge said their choice of prey could make them useful to conservationists to address mite species that are causing problems locally, without pesticides.
“The mite Varroa destructor is a significant pest to honeybees around the world, including Bermuda,” Dr Outerbridge said. “Some research has shown that there may be the potential of using pseudoscorpions to naturally control varroa mites within beehives.
“Most of the local beekeepers I know are not using the harsh pesticides typically employed by beekeepers in the rest of the world to manage varroa infestations in hives, so engaging the services of a natural predator could be an appealing prospect.”
Dr Outerbridge added that another mite species, Dermanyssus gallinae, was known to infest bluebird nests, causing harm and even death to bluebird chicks.
“Anyone who has erected a bluebird box and monitored its use has very likely noticed just how problematic these parasitic pests can be to a breeding pair of bluebirds,” he said.
“Current efforts to control mite infestations include scorching the inside of the box with boiling water after removing the chicks and nest, throwing away a heavily infested nest and making a new one using dry grasses or casuarina pine needles, and sprinkling diatomaceous earth under the nest.
“Perhaps another management tool could be introducing a few adult pseudoscorpions into the nest to hunt down the poultry mites.”
However, he said that for such an approach to be embraced, researchers needed to know if the “right kind” of pseudoscorpions were in Bermuda.
“First, we need to look for them and determine which species are established on Bermuda,” Dr Outerbridge said. “Members of the public can assist with this by reporting any they encounter.
“Places to search for the synanthropic species, those which are ecologically associated with humans, include warehouses, storerooms, timber yards, botanical gardens, plant nurseries, garden centres, farm buildings and animal stables.
“Some species, like the book scorpion Chelifer cancroides, are even found inside homes across North America and Europe, where they hunt for mites among the shelves of old dusty books.”
Anyone who spots a pseudoscorpion was urged to e-mail photographs and a short description of where they were found to environment@gov.bm.