Juvenile salmon return to Kingston

The Appletree Cove and the Carpenter Creek estuary abound with fish becomes obvious as the lowest tides shift toward midday in spring and summer.

This is not so much because we see the fish themselves, but rather because we see the birds that come to feast on them. When the tide is in, ospreys plummet talons first into the water and, when they catch something, speed away to elude eagles that will harass them until they drop their catch.

When the tide is out, herons stand sentinel where the shallow cove gives way to deeper water awaiting the fish that will come in with the tide. Fish come into the estuary with the incoming tides in the evenings to forage far up into the salt marsh 10-12 feet high. But below a 5-6 foot tide, the estuary drains and becomes a mudflat so that most of the fish must leave every morning. That is when eagles, herons, crows and gulls congregate along the narrow creek channel running out of the estuary before the tide fills the cove — a gauntlet of sharp-eyed predators the fish must run.

In addition to perch and sculpin, juvenile salmonids frequent the estuary this time of year to take advantage of its abundant food and relative safety of its murky water. Depending on the species, young salmonids (smolts) may spend days or months in the brackish water of estuaries, transitioning from life as freshwater to saltwater fish, and growing bigger to better survive their migration to the ocean.

In 2011-15, biologists from the Suquamish Tribe used beach seines to census fish species in the estuary and cove. It was a community affair with tribal members and Kingston residents, including schoolchildren and college students, all joining in to marvel at the diversity — particularly of salmonids — in the nets.

In addition to the sea-run cutthroat trout and coho salmon spawned in Kingston creeks, salmon species whose natal streams were elsewhere also turned up. These included pink salmon that only spend a brief time in estuaries, and chum and chinook that stay longer. Chum spawn in numerous Kitsap streams, and some may have been from Kingston creeks, but most were from hatcheries or streams further south. Chinook smolts were mostly hatchery fish, as streams in west central Puget Sound do not have sufficient flows to support large natural populations of this species.

Chinook, the largest salmon, can spend up to four months in estuaries between leaving their natal streams and reaching the ocean. Puget Sound chinook were declared threatened under the federal Endangered Species Act in 1999. Subsequently, estuary restoration was deemed critical to the species recovery: increasing river and hatchery production doesn’t work if there is not enough estuary habitat for them as smolts.

Hatchery chinook have the same habitat requirements as wild fish and are just as important to local fishers and endangered southern resident orcas. Their presence in restored North Kitsap estuaries like ours is a good sign that estuary restorations work, and wild chinook will also be able to utilize these estuaries more as their numbers grow.

Melissa Fleming recently retired as program director at Stillwaters Environmental Center, which has a monthly column in this newspaper.

Suquamish biologist Paul Dorn shows seine contents to some youngsters.