Bees and other pollinators prefer salty nectar when it is available. This refers to bees, butterflies and flies. When sodium was added to flower nectar, the number of visits by pollinators rose.
A team of researchers from various institutions in the USA has had a paper published in the journal, Biology Letters.
The researchers describe in their paper how they added sodium to the nectar produced by five flower species in potted plants on the grounds of the University of Vermont. Then they observed and recorded local pollinator interaction.
Animals and humans generally prefer certain foods when there is a higher sodium content, so the researchers wondered if this might carry over to pollination insects like bees as well.
This unrelated 3:46-minute video by Frederick Dunn asks if bees drink salty water. He used iodized salt in the experiment:
Initially the potted plants were kept in a greenhouse, and the researchers added artificial nectar to every plant. They left half the plants in their natural states, and the other half contained higher sodium levels. These same plants were then moved to the meadow on the grounds of University of Vermont and left in pots on the ground.
For one month, researchers filmed the pollinators as they arrived, and visited the natural plants in the meadow as well as the ones that had been placed there in pots. They noted which pollinators visited, and how many visited the plants.
According to their data, the sodium-enhanced plants received twice as many visits as the other potted plants and the natural meadow plants. There was also greater diversity of pollinators visiting the salty plants. Bees, flies, and butterflies.
The researchers concluded that their findings indicate saltier plants stand a better chance of being visited by pollinators. This might be a very strategic piece of information if the presence of pollinators drops due to such things as climate change and human activities like pesticide use, habitat loss, monocultures, and more.
Their paper also notes that according to prior work, some flowering plants may be affected with lower sodium levels as water cycles change in their region.
This is clearly an area where further research would be beneficial.