Title: Stream Habitat Assessment Project: Afognak Island
Project Year and Number: 1992: R047
Other Fiscal Years and Numbers for this Project: None
Principal Investigator (PI): Mark Kuwada, Alaska Department of Fish & Game
Assisting Personnel: Kathrin Sundet
Research Location: Kodiak Island
Restoration Category: Damage Assessment
Abstract: Coastal stream systems and associated riparian areas are important habitat for a number of species that were injured by the Exxon Valdez oil spill. Stream surveys by ADF&G intend to focus on habitats that are of potential importance to pink salmon, Dolly Varden char, cutthroat trout, harlequin ducks, and bald eagles. These species are documented to have sustained injuries as a result of the oil spill, and all are associated to some extent with stream environments. Pink salmon, Dolly Varden char and cutthroat trout are anadromous species of fish that utilize freshwater environments for important life functions such as spawning, rearing and over wintering. Harlequin ducks use freshwater streams for nesting and feeding activities. Bald eagles frequently nest in the vicinity of freshwater streams where feeding opportunities are abundant.
Pink salmon exhibited higher than normal egg mortality rates in oiled areas (70 percent in 1989; 50 percent in 1990), and fry showed evidence of gross physical abnormalities. Dolly Varden char and cutthroat trout sustained higher than normal annual mortalities (up to 32 percent) compared to unoiled areas; cutthroat trout had reduced growth rates in oiled areas. In excess of 200 harlequin ducks died from direct exposure to oil in 1989, and studies indicate that ducks may have suffered a nearly complete reproductive failure in the Prince William Sound oil spill area during 1990 and 1991. At least 144 bald eagles died as a result of direct exposure to oil or by eating oiled carrion, and bald eagles have experienced higher rates of nest failure in oiled areas.
Certain development activities, particularly clear-cut logging of mature forests, represent a potential threat to fish and wildlife resources that rely on these habitats for critical life functions. This threat is expressed as an incremental loss of habitat that may impede the recovery of injured species populations or may inflict additional injury. The proposed surveys are intended to focus on private lands that are scheduled for logging or other types of major habitat alteration. Unless these surveys are conducted in 1992, opportunities may be lost to identify and protect key habitats that sustain fish and wildlife populations. The surveys will cover the entire spill area.
Survey data will be designed and presented to provide the basic habitat information needed to identify and prioritize the most important habitat areas for protection and enhancement decisions.
Another benefit is that previously unidentified streams will be added to the ADF&G Catalog and Atlas of Anadromous Waters and consequently protected under the provisions of the state's Anadromous Fish Act and Forest Practices Act.
Stream habitat surveys will be coordinated with ADF&G Sport Fish and Wildlife Conservation division efforts to restore other injured species habitats. In the case of Dolly Varden/cutthroat trout, surveys may enhance the possibility of recovering tagged study fish and provide new information on Dolly Varden/cutthroat trout distribution and habitat, particularly in areas outside of Prince William Sound. In the case of harlequin ducks, key habitat requirements remain undefined for birds in the oil spill area; therefore, survey results can assist in documenting features that promote habitat use. It is also possible that surveys may record observations of previously unidentified bald eagle nesting habitat.
Fish - Salmon
Seabirds - Sea ducks
|Fields of Expertise||
Geographic information systems/Mapping
Proposal: PDF Not Available
Funding Recommendations: View
Funding Detail For: 1992
Quarterly Project Tasks For: 1992
Annual Report: 1992: Not Applicable
Final Report: View
Publications from this Project: None Available