Plan Your Trip!

Intertidal Flat at Grays Harbor NWR

When shorebirds stop to feed in Grays Harbor, they feed on worms and other invertebrates in the substrate. Shorebirds move with the tides wading in shallow water edges and freshly exposed flats. Birding sites differ in habitat characteristics and shorebird viewing is reliant on the tide, exposure of intertidal flats, and coverage of shallow water.

Grays Harbor National Wildlife Refuge is one of the best places to view shorebirds from the Sandpiper Trail. The location at the backside of Grays Harbor and its distance from the mouth results in a longer period when the intertidal flat is exposed for shorebirds to feed – it is one of the first areas to expose mudflat as the tide recedes and the last area to be covered with the incoming tide. The recommended time to view shorebirds is during the period from 3 hours before high tide to 3 hours after high tide. During this time, birds are closer and more concentrated for better viewing from the Sandpiper Trail. To plan your visit, refer to the Best Shorebird Viewing Times at Grays Harbor National Wildlife Refuge.

Based on shorebird surveys, the peak migration typically occurs between the last week of April through the beginning of May. If you’re heading to Ocean Shores, Westport, Grayland, and Tokeland to see shorebirds, you can reference the area-specific tide charts.

Semi-Palmated Plover Photo by John Whitehead

Weather conditions such as wind and storms can greatly alter tides in Grays Harbor so good shorebird viewing is dependent on a number of factors and can be unpredictable.

For coastal viewing, tidal cycles are not as critical. High tides along the coast are about 20 minutes earlier than at Grays Harbor National Wildlife Refuge, inside the harbor.

Water Level Information: Storms generally cause higher surface water conditions in the estuary for a few reasons:

1) Heavy rains in previous days cause rivers and hillsides to rapidly drain into the estuary, which can add to tide level. If soils are saturated count on quick, heavy runoff.

2) On-shore winds push water into the dead-end (bathtub-like) basin and as it fills, mudflats become inundated and can flood into the saltmarsh. Of course strong winds exacerbate the situation.

3) Low atmospheric pressure (associated with stormy conditions) allows tide waters to rise vs high atmospheric pressure which pushes down on the water surface. These conditions, often in combination, cause the tide to come in as much as 2-3 hours early and cause tide levels to be above predicted tide peak levels. Check the predicted tide level for 'Aberdeen' and consider the recent and current weather conditions to plan an appropriate arrival time. Plan your trip and expect to spend a few hours to maximize viewing potential.

Generally tides at or near 8-8.5' are good for consolidating shorebirds into limited area of mud flat and make viewing easier. However, higher water levels (predicted or not) cause water to cover more mud. So that means go early to see them before water covers the mudflat and stay until the tide recedes to see the birds come back and resume feeding.

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