Summary

Description

The Hawaiian duck or Koloa maoli Anas wyvilliana is endemic to Hawaii and one of three extant waterfowl species occurring on the Hawaiian Islands. Relatively common during the early 1900s, the Koloa has since experienced a significant statewide population decline because of factors that include wetland loss, over harvest by hunters, and introduced mammalian predators. More recently, the genetic integrity of the species has been threatened by hybridization with feral Mallards. Consequently, Koloa was listed as a Federallyendangered species in 1967 and has the highest recovery priority for the four listed wetland birds that occur on the main Hawaiian Islands. Kauai is the only island that likely supports a viable population of pure Koloa, and Hanalei and Hulia NWRs are at this time the number one and two most important sites for Koloa in the state. Beginning in December of 2010, we used grant money from Region 1 Refuges, Ecological Services, Migratory Birds and Oregon State University, and inkind contributions from Kauai NWRC to initiate a capture, banding and survey protocol that can achieve multiple monitoring and research objectives listed in the Draft Hanalei and Hulia NWR CCP and Hawaiian Waterbird Recovery Plan. The protocol for our survey also allows us to move forward with key conservation and research activities that will support implementation and assessment of the refuges CCP and inform refuge staff about the value of habitat management programs on both refuges. The grant provided by the Inventory and Monitoring program, USFWS Region 1, allowed us to continue and expand on that work. Our specific objectives for this grant include: 1. Investigate the value of using banded birds and a markresight analysis approach to estimate the population size of Koloa using Hanalei and Hulia NWRs.2. Determine the prevalence of MallardKoloa hybrids on Hanalei and Hulia NWRs.3. Collect data to help refine the MallardKoloa hybrid key to improve implementation of hybrid removal activities at both Kauai refuges and James Campbell NWR on Oahu.4. Conduct field surveys at Hanalei and Hulia to survey for extent and seasonality of intraisland movements. 5. Develop operational survey to annually detect and remove hybrids from Hanalei and Hulia NWRs; explore application of these methods to James Campbell NWR on Oahu.