Plans are under way to strip-mine coal deposits in the Beluga field near the west side of Cook Inlet and transport a coal slurry via pipeline to a thermal electric generation plant opposite Anchorage on the Inlet. Impact on tidal areas may be minor, but thermal pollution of the waters is a possibility.
Development plans for tin and tungsten deposits in the Lost River area of Alaska's Seward Peninsula are under way after several years of faltering starts and stops. These activities and possible extraction of gold lying offshore from Nome may ultimately have some effect on these coastal areas. Methods for recovering gold, regardless of the type, would disrupt marine and estuarine environments used by marine birds (Bartonek et al. 1971), and transportation of ores would also increase freighter traffic in the Bering Sea.
Timber Resource Development
Although the timber industry has long been established along the coast from Washington north through southeastern Alaska, timber harvests are rapidly expanding on U.S. Forest Service lands in Alaska. The impact of this industry is principally on terrestrial ecosystems, but certainly log rafting in estuarine areas, disposal of wastes from pulp mills, and freighter traffic transporting wood pulp or logs to Japan and west coast markets contribute to the chronic degradation of marine bird environments. Recent meager studies on the Vancouver Canada goose (Branta canadensis fulva) in southeastern Alaska have pointed out the importance to this species of coastal timber stands for nesting and estuarine environments for brood rearing and wintering. This essentially nonmigratory goose (Hansen 1962) may be particularly vulnerable to logging activities in these areas. Similarly, recent evidence indicates that marbled murrelets may nest in large conifer trees adjacent to the coast, from northwestern California to northern southeastern Alaska (Harris 1971; Savile 1972). If this is true, logging may eventually greatly restrict the breeding of this numerically important inhabitant of northern coastal waters.
Assessment of Resource Development and Potential Conflicts with Marine Bird Conservation
Although extraction of hard mineral resources, expansion of the timber industry, and resultant increases in human pressures along North Pacific and Arctic coasts will ultimately affect northern marine bird populations, current and proposed activities of the petroleum industry pose the most immediate threat to marine birds. Chronic degradation of estuarine and marine coastal waters by logging wastes, pulp mill and sewage effluents, and bilge oils is an insidious process, the impacts of which will be difficult, at best, to quantify. Results of a major oil spill or even low-level contamination of marine ecosystems with oil will be more apparent, however. For this reason, and the fact that the industry is expanding rapidly into the North, most of this discussion will be directed at the impacts of oil development on northern marine birds.
Potential sources of adverse environmental degradation affecting these birds resulting from oil and gas exploration, development, and production include: (1) oil discharges into marine waters, both chronic and catastrophic, (2) gravel excavation and dumping in coastal areas, (3) seismic activities, (4) discharge of drilling mud and drill cuttings into marine waters, including toxic heavy metal constituents of drilling mud, (5) disturbance resulting from petrochemical activities, and (6) increased human populations resulting in interference with critical life processes and increased hunting of game species. Each source of environmental change will vary by latitudinal and seasonal factors in their effects upon the birds. We consider herein only coastal and ocean floor developments and their anticipated generalized impacts on populations.
Although this is a discussion of "northern" marine birds, it is important to remember that we are considering a diverse avifauna existing in an environmental gradient from temperate to polar regions. In general, the more southerly portions of this marine environment are characterized by a greater diversity of species, more complex food chains, and a resultant greater stability (Dunbar 1968). Arctic marine ecosystems, on the other hand, are characterized by numerical dominance by a few species, relatively simple food chains, and an inherent instability or fragility (Dunbar 1968). According to Dunbar, arctic systems are regulated primarily by temporal oscillations in the physical environment, whereas biological interactions (e.g., competition, predation) are considered more significant in the maintenance of temperate and tropical ecosystems.
Because of their relative instability, arctic ecosystems are more susceptible to alteration by extreme environmental perturbation, either natural or man-imposed (Burns and Morrow 1973). Slow growth and maturation rates of the avian constituents of these ecosystems and resultant long recovery periods (Ashmole 1971) further aggravate this situation.
Regardless of their seasonal availability, these arctic waters constitute some of the most productive areas for seabirds in the western hemisphere (Bartonek et al. 1974). Upwelling, nutrient-rich waters, combined with intense and prolonged incident radiation, result in lush phytoplankton "blooms" that form the foundation of relatively simple but numerically strong plant and animal communities (Ashmole 1971). A relatively small number of avian species have evolved to take advantage of this seasonally available food supply, and the ability to migrate to lower latitudes in winter is a characteristic of most arctic-nesting species. Because summers are short in arctic regions, early arrival and a synchronous breeding schedule are necessary to enable the young to leave the breeding grounds before severe weather conditions prevail (Ashmole 1971). Arrival of these birds generally coincides closely with the earliest availability of nesting habitat and food (Williamson et al. 1966). Migration, molting, and reproduction place tremendous stresses on these birds, and as a result, arctic-nesting species tend to reproduce less often and at older ages than do those of more temperate regions (Ashmole 1971).