Seasonality and prevalence of pollen collected from Hawaiian nectarivorous birds: a summary

摘要

This article is a research summary by the 2017 Winter/Spring Hawaii Audubon Research Grant Awardee Kathryn N. van Dyk. The subject of this published work differs slightly from that described in the grant proposal. The research team was able to exam nectar preference and seasonality trends from the birds at Hakalau. However, they did not include an analysis on forest fragmentation because they found extremely low levels of pollen on the birds from the kīpuka, the fragmented forest. They decided that more sampling was needed before definitive conclusions could be published and suggested the results obtained so far are important and meaningful. The following is a link to the early view of the full published work with Pacific Science: https://pacificscience.files. wordpress. com/2018/12/pac-sci-early-view- 73-2-l.pdf Hawaiian nectarivorous forest birds play a vital ecological role as pollinators in Hawaiian ecosystems, as many flowering plant and bird species have coevolved with one another (Sakai et al. 2002, Price and Wagner 2004). However, little is known of the nectar resources used by Hawai'i's nectarivorous birds, other than 'ōhi'a (Metrosideros polymorpha), how seasonality influences nectar availability, and how nectar preference differs by bird species (Richards and Block 1973, Warning et al. 1993). By addressing these questions, biologists may better understand and conserve Hawaiian ecosystems and biodiversity. To quantify which plant species are important to Hawai'i's nectarivorous birds, we studied pollen samples collected from birds at Hakalau National Wildlife Refuge on the windward side of Hawai'i Island.