Migratory Birds

American black duck ( Anas rubripes) utilize inland and tidal freshwater and brackish marshes throughout the Chesapeake Bay and are considered to be an indicator species of the ecosystem’s health. Thus, conserving and increasing black duck habitats will subsequently benefit the general health of the bay. The goal of this study was to create a mechanistic model to determine the amount of...

The Laysan teal has the most restricted range of any duck species and is especially vulnerable to extinction because of its small population size and vulnerability to climate change. The species was believed to be endemic to one island until new sub-fossil evidence and ancient DNA-testing revealed Laysan teal were widespread across the Hawaiian archipelago. Despite its previously wide distribution...

USGS and Oregon State University (OSU) have joined forces to support USFWS with research needed help manage and recover the endangered Hawaiian duck, locally known as koloa maoli. Hybridization of koloa with feral Mallards on O‘ahu and Maui is believed to have resulted in complete introgression in those populations (Engilis et al. 2002), and Kaua‘i is the only island that likely supports a viable...

The federally endangered nēnē, or Hawaiian Goose, once present on most of the Hawaiian Islands, was found only on Hawai‘i Island by 1900. This remnant population was reduced to as few as 30 individuals by 1952 due to the combination of unregulated hunting, introduced mammalian predators, and large-scale habitat degradation. Nēnē have been restored to a few places like Hawai‘i Volcanoes National...

Hawai‘i has more endangered species than any other state - over 394 species. In spite of this fact, there is not a central clearing house for information on the status and trends of these species. Information is spread over the following areas: 1. USGS maintains some information on Forest Birds. 2. USFWS maintains summary data on listed and proposed plants. 3. The University of Hawai‘i maintains...

Population trends suggest that the Florida Grasshopper Sparrow may go extinct within five years. USGS research aims to collect demographic information to help identify the current status of the species.

USGS scientists sampled grebes in California lakes to compare mercury levels in these predators versus the small fish they prey on—developing a new tool for water quality monitoring.