A cactus no bigger than a paperclip grows across the rocky eastern slopes of the Kaibab Plateau. Its thin, long spines protrude from its rotund body like a plump hedgehog.
This species of Pediocactus, sometimes called the bristly plains or Kaibab pincushion cactus, is a species of concern to ecologists, who have seen decreasing numbers of the petite succulent in the past decade.
These wee cacti can disappear underground when stressed, making population data challenging to obtain. Still, researchers at Northern Arizona University are studying pollinators attracted to the cacti’s pearly yellow flowers as they open in early spring.
For three consecutive seasons, they recorded data like pollinator species and time spent on flowers. A closely related cactus species experienced extremely low flower visitation in 2016 and 2017, so the large number of pollinators seen in recent years was surprising.
Bees visited about 10 flowers per minute. Sweat bees were the most frequent, though flies were also seen nestling into flower cups. The same research group is growing pollinated seeds in a greenhouse to see just how successful these cactus pollinators are.
Pollinators are essential for flower reproduction and drive biodiversity through their role in seed production. Understanding which pollinators visit Pediocactus flowers supports efforts to maintain genetic diversity, a critical part of conserving this native, compact cactus.
This Earth Note was written by Danika Thiele and produced by KNAU and the Sustainable Communities Program at Northern Arizona University.
