PERTH’S burbs are full of bees and a new research project aims to find out how many species there are using DNA barcoding.
Bee scientist Kit Prendergast has been surveying native bees in WA’s urban southwest for more than two years.
The region is a biodiversity hotspot and she’s identified about 150 species in Perth alone.
The majority of Australian native bees are very different from the introduced European honey bees: “Most of them are solitary and don’t make honey, they don’t live in hives or large colonies, and each female can reproduce,” Ms Prendergast says.
But species are hard to identify by sight: “Some of them look so similar you can only tell them apart by looking at the genitalia under a microscope.
“Then there are cryptic species – they look extremely similar but are still in fact genetically distinct,” indicating they do not interbreed.
In some cases the male and female might look so different you’d never guess they were the same species, unless they’re seen breeding.
DNA barcoding is a surer tool for identifying species: DNA is extracted from a bee’s leg and the DNA from a particular gene is sequenced. Each species has a unique DNA sequence which acts as a “barcode”.
“It will really help us understand the diversity of bees we have in WA,” Ms Prendergast says.
Her ‘Barcoding Bees for Biodiversity Assessments’ project has been awarded $5000 from the NSW-based company BeeInventive. They’re donating all of the profits from their flow pollinator house – which allows honey to drip out of hives into waiting containers with less bee disturbance than traditional harvesting – to eight not-for-profit, pollinator projects in Australia and the US.
“With this funding I’ll able to identify species with confidence,” Ms Prendergast says. “In Australia much of our species have not been described, and so by DNA barcoding them I’ll be able to create an inventory of the biodiversity of bees in the ‘burbs.
“This is very important so we can identify hotspots of bee biodiversity and see what environmental factors enhance the diversity of bees. Our cities are expanding, so we really need to make sure we protect our pollinators as our human population grows.”
Most native bees are reliant on remnant bushland: The smaller ones, some as little as 2mm long, have a much shorter flight radius than European honey bees and can’t travel far to remnant pockets of native vegetation.
“If they’re isolated from other bushlands, they can’t just fly to another one: for most native bees their flight ranges are only 500m or less”; Ms Prendergast says.
But suburban gardens can provide some respite if they have the right plants.
Native bees seem to do okay co-existing with European bees provided they’re not all competing for the same few plants: “If we keep clearing keystone native plants like the marri, jarrah and native pea plants, which are especially common in the bushland remnants, then there’s not going to be enough foraging resources for all of them to go around.”
by DAVID BELL