Calling on citizen scientists to help fill the gap in the thousands of unphotographed native plants

New research has found that 20 percent of all native Australian plant species don’t have a verifiable photograph in their natural habitat.

This can have consequences for the many species which are difficult to identify in the wild, which may go extinct if scientists cannot properly identify them with the help of photos. 

“We had assumed every plant species would have simply been photographed by someone, somewhere, throughout history. But it turns out this isn’t the case,” says Associate Professor Will Cornwell, from the University of New South Wales Sydney, and senior author of the study in New Phytologist.

“This is where citizen scientists can come in and help us fill this gap with their photos.”

Why are plant photographs necessary?

Photos are an important part of documenting plant species for botanists and taxonomists – scientists who name, describe, and classify organisms. Plant characteristics which can get lost over time, like flower colour, don’t degrade in photos like they do in samples. Photos can also provide additional information like leaf orientation, bark appearance.

“Having a comprehensive photographic set helps us to be confident in our identifications,” says Thomas Mesaglio, a PhD student at UNSW and lead author of the study.

“Particularly when it is practically challenging to collect and preserve the entire plant, photos complement the physical voucher by showing the soil type, the habitat it’s growing in, and other species growing alongside it.”

To examine the photographic record of Australian plant species, the researchers surveyed 33 major online databases of plant photos. They discovered that not all plant species are photographed equally.

“We noticed a charisma deficit, so the species that tend to be harder to see are the ones missing out. They may have innocuous or pale-looking flowers or be smaller and harder to spot grasses, sedges and herbs,” Mesaglio says.

Geography also plays a part, because while the south-eastern states’ records are quite comprehensive, 52% of all unphotographed species were found in Western Australia.

“The primary ‘hotspots’ for unphotographed Australian plants are areas with high plant diversity, but the environments are rugged and often difficult to access, particularly by road,” Mesaglio says.

“But it means there’s an exciting opportunity to visit these locations because we might capture something that has never before been photographed.”

Citizen scientists can capture those much-needed snaps

This is where citizen scientists come in.

“Because digital photography is so accessible now, anyone can also help make a meaningful contribution to science using the camera in their pocket,” says Mesaglio.

Through the iNaturalist platform citizen scientists can upload their plant pics to be identified by experts, and the data can be shared with aggregators like the Atlas of Living Australia and the Global Biodiversity Information Facility to be used in scientific research and conservation.

“Since April last year, we’ve identified nearly 10 per cent of those previously unphotographed species thanks to members of the public uploading their photographs and experts who’ve kindly identified them,” says Mesaglio.

“There could be many more in personal collections, or behind paywalls, just waiting to be shared.”

The researchers recommend that a standardised system for scientific plant photography should also be developed, beginning with a requirement in the International Code of Nomenclature for Plants to include at least one field photo where possible in new species descriptions.

“Of the species with photographs, many have a single photo. We not only want to capture those unrepresented species but also continue building the photographic record for all species,” says Mesaglio.

“Doing so will help us identify, monitor and conserve our native species for generations to come.”