Science1 publisher2 min readPublished
Australia lacks the data to tell which of its 1,700-plus native bee species are at risk, review argues
Australian bee researchers say only three of the country's more than 1,700 native bee species are on the national threatened species list. Their review blames thin research funding for the missing data and sets out a conservation plan built on behaviour studies and long-term monitoring.
The Scientist · Science desk
What happened
- The global IUCN Red List identifies six native Australian bee species, twice the number on the national list.
- Listing a species requires data on its population size and distribution plus a recognised scientific name, and many native bees lack that information.
- A 2009 paper named land clearing, disease and competition from introduced plants and bees as threats; the authors say climate change and habitat loss remain the most pressing.
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Why it matters
- constraint Protection for an Australian bee has to wait for taxonomy and fieldwork, since a species without an accepted name and population counts cannot pass the national listing test.
- exposure Species whose habitat burned in the Black Summer fires stay off the national list until someone collects the population data the authors say is missing.
- decision Funders deciding where conservation money goes now face the authors' case that obscure bees with no crop value need it more than the better-known crop pollinators.
Three listed species out of more than 1,700 is fewer than two in every thousand [1]. Adding the 11 Black Summer candidates would take the national count to 14, still under 1 percent of the known species [2]. Both numbers are limited by the listing test. They count bees that have been studied well enough to pass it [11].
The denominator moves, too. Researchers described more than 115 new species last year [2], about 7 percent of the current total if both figures are taken at face value [3]. They included Megachile lucifer and 71 species of resin pot bees in the genus Megachile [2]. Some are tiny: Euryglossina clypearis grows to 1.8 millimetres [3]. A newly named bee starts with no population record, and the listing test asks for one [11].
The thing this review doesn't tell you is how fast any Australian bee population is shrinking. The decline it cites is worldwide, driven by habitat destruction, invasive species, pesticide use and climate change [4], and the authors drew on overseas research as well as Australian work [5]. Their Black Summer estimate is based on how much bee habitat the 2019-20 fires destroyed [10]. Burned habitat is a reasonable proxy for lost bees. It assumes populations fell in step with the habitat, and for many species there are no counts to check that against [11]. The authors wrote that "Even native bee researchers don't have all the answers." [17]
They trace the shortfall to money. Research and funding for native bee conservation have been scarce since the 2009 paper, according to the authors [7]. Attention goes to crop pollinators, such as the buzz-pollinating Amegilla, and to the introduced European honeybee [15]. The authors wrote that "bees that don't pollinate popular food crops actually need the most help." [14]
The plan is split by timescale. In the short term the authors point to regulating pesticides that harm bees and protecting native habitat; in the long term, to monitoring programs that bring together researchers, farmers and community members [13]. They also want studies of how bees navigate, search for flowers and choose plants, to judge how species will cope with climate change [12]. I think monitoring matters most for the listing problem, because it is the only item in the plan that produces repeated population counts [11][13]. I'd expect it to help only if the programs run for years: one survey can estimate a population, but a rate of decline needs repeat counts.
What to watch
- Whether any of the 11 Black Summer candidate species are nominated for, or added to, Australia's national threatened species list.
- Publication of the species-by-species list behind the 11 candidates and the habitat-loss data used to select them.
- Whether government or research funders back long-term native bee monitoring programs involving farmers and community members.