Nocturnal Moth Pollination in Montane New Zealand: Insights From Pollen Loads and Exclusion Experiments

Abstract

While most pollinator studies have focused on diurnal taxa, nocturnal moths are increasingly recognised as important pollinators across diverse ecosystems. However, experimental studies on moth pollination in natural ecosystems, particularly montane regions, remain limited. This study examines the role of nocturnal moths as pollinators for four native montane shrub species in New Zealand using pollen load data, a pollen-transport network, and pollinator exclusion experiments. We found that many moths transport Dracophyllum, Veronica brachysiphon, and Leptospermum scoparium pollen. Pollinator exclusion experiments revealed that nocturnal pollinators significantly contribute to seed set in Dracophyllum, but not in Leptospermum scoparium or Discaria toumatou. This study highlights the value of combining observational pollen load data with pollinator exclusion experiments to assess the role of nocturnal moth pollinators for subalpine shrubs.