Invasive rats consuming mountain flax nectar – resource competitors and possible pollinators?

Abstract

The long history of human-mediated species introductions has resulted in a multitude of novel interactions around the globe. Many of these interactions have been to the detriment of native species. In New Zealand, the ship rat (Rattus rattus) is considered culpable for the rapid declines in the populations of numerous bird species. While seed masts have been implicated in rat population booms, alternative food resources, such as floral nectar, may play an underappreciated role in rat-bird interactions. Here, we present video footage and nectar volume data that indicate likely resource competition between rats and birds for floral nectar. Additionally, this footage indicates possible pollination services by rats. These findings suggest that attention should be paid to nectar as a limited resource that may bolster rat populations, as well as attract rats for pollination services.