Columbia River Estuary

Ecology & Conservation 

Habitat Description
Shorebird Use
Causes of Disturbance to Shorebirds
Management Issues and Research Priorities

Habitat Description:
A number of different habitat types relevant to shorebirds can be found within the 60 river miles along the Columbia River. Habitat types include intertidal mud and sand flats, intertidal marshes, intertidal forested wetlands, sand/pebble shores, and estuarine waters, as well as sand dunes.

The most prevalent habitat type within the site, other than estuarine waters (which comprise the majority of the site area) is the intertidal marshes, followed by intertidal mudflats. There are a few areas comprised of inland wetlands (e.g. Julia Butler Hansen NWR). These small inland wetlands can be described as seasonal freshwater marshes. The vast majority of the site is natural in origin. The site is tidally influenced and water levels are also highly influenced by dams upriver. 

Shorebird use:
More than 20, 000 shorebirds use the Columbia River Estuary each year. Species include: Black-bellied Plover, Semipalmated Plover, Killdeer, Greater Yellowlegs, Spotted Sandpiper, Whimbrel, Marbled Godwit, Ruddy Turnstone, Red Knot, Sanderling, Western Sandpiper, Least Sandpiper, Dunlin, Short-billed Dowitcher, and Red-necked Phalarope.

Causes of Disturbance to Shorebirds:
Although the site is largely undeveloped, many activities that occur in or near the site can affect shorebirds. The major causes of disturbance to shorebirds at the site include:

·  Human-caused disturbances, including recreation, excessive noise, and dogs.

·  Habitat alterations/destruction and altered hydrologic regimes caused by sea-level rise, dams, dikes, removal/lack of large woody debris, and sediment accumulation.

·  Altered climate and extreme weather events caused by climate change and El Nino and La Nina events.

·  Potential for disturbance from oil spills.

Management Issues and Research Priorities:
The Northern Pacific Coast Regional Shorebird Management Plan (“Plan”, revised March 2000) outlines a number of management issues and research priorities for conserving shorebird species in the Northern Pacific Region. Priorities for research and monitoring, management, habitat protection, and outreach are briefly listed below.

Of the research and monitoring priorities listed below, the lack of regular monitoring of shorebird populations is the largest barrier to further meaningful shorebird research or management. No regular monitoring of shorebird populations is currently done in the Columbia River Estuary. A coordinated, large-scale, and annual or semi-annual survey effort is needed. A surveying effort similar to the Program for Regional and International Shorebird Monitoring (PRISM) following International Shorebird Survey protocols would be extremely valuable.

Additional research and monitoring priorities identified in the Plan that apply to the estuary include:

·  Monitoring the condition, distribution, and availability of shorebird habitat in the estuary;

·  Examination of shorebird response to introduced species, and development of control methods;

·  Identification and monitoring of specific areas where contaminants have a reasonable likelihood of impacting shorebirds, and study of the effects on shorebirds of various contaminants (e.g., lead, agricultural, and industrial chemicals, oil, plastic particles);

·  Development of strategies to reduce threats to shorebirds from contaminants, disturbances, introduced species, hazardous structures, human- and predator-caused mortality, and habitat loss or degradation;

A number of other management recommendations are outlined in the Plan that may apply to the estuary, including:

·  Facilitation and promotion of public enjoyment of shorebirds (e.g., building observation platforms and kiosks at key shorebird locations, organization of shorebird festivals, encouraging volunteer shorebird monitoring by the public, development of documentaries and K-12 education programs, and media outreach);

·  Education of agencies, NGOs, landowners, and the public on shorebird ecology and population status. Target groups for outreach efforts include the agricultural community, watershed councils, landowners of important shorebird sites, the aquaculture community, hunting clubs, schools, tourism agencies, and public officials;

·  Prioritization and funding of wetland protection, restoration, and enhancement projects;

·  Provision of access to data, maps, and other information to county and municipal planning agencies to promote management efforts for shorebirds at the local scale;

·  Protection from human disturbance of key nesting, roosting, and foraging sites;

·  Protection of important sites using tools like acquisition, conservation easements, and voluntary conservation plans;

·  Removal and/or prevention of deleterious silt accumulation in marsh and mud flats;

·  Planting or encouraging growth of native vegetation conducive to shorebird use in restored areas;

·  Managing water levels and vegetation to create conditions suitable for use by wintering or migrating shorebirds, including discing and mowing where and when appropriate.