Species from faeces: tracking bats through poo 'barcodes'
A new DNA tool can identify multiple species of the flying mammal in a single glob of guano. Amy Middleton reports.
There are an astounding 1,300 species of bats known to science, but around 16% of these are endangered thanks to urban development, deforestation and introduced species.
Conservation efforts aren’t helped by the fact that they’re notoriously difficult to study, with their nocturnal sleep-cycles, long flights and very subtle differences between species.
Now, a team of researchers has come up with a handy way to monitor the whereabouts of different bat species without having to engage with the animals themselves.
"Species from Faeces" was developed by a team led by Faith Walker, a bat ecologist at Northern Arizona University in the US and published in the journal PLOS One. It’s a tool in the form of a test which functions just as its name suggests – identifying different bat species by analysing their poo.
Using DNA analyses, the test confirms a species from its poo by picking out mitochondrial gene segments that are particular to each bat and recorded on a database that currently includes a third of the world’s bat species.
Bat poo, or guano, is much easier to collect and study than the animals themselves and can hold a plethora of information about its animal host.
The tool facilitates easy identification, much like the barcodes on grocery items, from a glob of guano, “and determine all the species that contributed to the sample, and can do so for bat species from around the world,” Walker explains.
“With global declines in bat populations and emerging diseases such as White-nose Syndrome in North America, it is increasingly important to know which species are where […] or to verify identification of species that appear similar.”
During testing, the tool correctly identified 54 different species of bat from poo samples and successfully distinguished relevant DNA from that of the bats’ insect prey.
“Our assay has applications worldwide for examining disease impacts on vulnerable species, determining species assemblages within roosts, and assessing the presence of bat species that are vulnerable or facing extinction,” the researchers write.
The team also hopes for a flow-on effect from the development of this tool to potentially benefit other animals in decline.
“The development and analytical pathways are rapid, reliable, and inexpensive and can be applied to ecology and conservation studies of other taxa,” they write.