Unexpectedly low paternal diversity is associated with infrequent pollinator visitation for a bird-pollinated plant

The behaviour of pollinators has important consequences for plant mating. Nectar-feeding birds often display that results in more pollen carryover than insect pollinators, which is predicted to result frequent outcrossing and high paternal diversity bird-pollinated plants. We tested this prediction by quantifying mating system parameters bird visitation three populations an understory herb, Anigozanthos humilis (Haemodoraceae). Microsatellite markers were used genotype 131 adult plants, 211 seeds from 23 maternal populations. While rates high, estimates surprisingly low compared with other Despite nectar-feeding being common at the study sites, visits A. flowers infrequent (62 over 21,552 recording hours motion-triggered cameras, or equivalent one visit per flower every 10 days), majority (76%) a single species, western spinebill Acanthorhynchus superciliosus (Meliphagidae). Pollen counts 30 captured honeyeaters revealed comprised just 0.3% total load. For spinebills, only 4.1% load, equated average 3.9 grains bird. Taken together, our findings suggest loads floral visitors have led observed herb. As such, we shed new light on conditions can lead departures plants competing pollination services generalist birds.