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The king salmon swim upstream to spawn and complete their lifecycle, also providing a meal for a dipper. On the hillside, it’s the elks’ breeding season, and a black bear fattens up on berries before winter closes in across this magnificently diverse landscape.

A fledgling bald eagle is the fastest-growing young bird in North America, yet it faces a challenging journey to maturity and acquiring its iconic adult plumage. As autumn storms arrive, king salmon migrate to river mouths and their freshwater spawning grounds, while resident orca pods expertly hunt them for a nutritious meal.

In springtime, the sheer cliffs along the wild coastline of the park have become home to the common murre, a bird that comes to land only to breed. The eagles, further along in their nesting process, have a rapidly growing eaglet in need of constant nourishment, and, unfortunately, the murre colony makes easy pickings for them.

While the male bear is distracted by harbor seals, the cubs make their escape. Out at sea, the seals are safe from bears, but not from killer whales. Just to the north of the park lies a deep underwater canyon that can only be explored by submarine. It’s a birthing place for sharks, and a world of rarely glimpsed marine life.

In the summer, the denizens of Olympia National Park feed in the lush alpine meadows, while a mother bear and her cubs forage for food along the shore. Tasty and nutritious crabs make a perfect snack, even in their shells!

Sigrid concludes this "personal journey into the unknown" with optimism about harnessing creativity in order to live a more fulfilling life with Alzheimer's even though it might not slow it down. We have to live in the present!

Spring has sprung and new life stirs on the Olympic Mountain ranges, the third great wilderness environment of this most diverse of national parks. The eponymous Olympic marmots awaken from their winter slumber to enjoy a feast, but must remain on the lookout for the bald eagle.

A year has gone by and Sigrid is back in Tacoma to spend time with her sister, Sylvia. Things have changed quite a bit, and Sigrid shows us Sylvia's new setup.

Gray whales migrating north from Mexico must pass through dangerous waters off the coast of Olympic National Park, where groups of orcas are actively hunting them and their young.

A great deal happens beneath the waves of the park’s dramatic coastline. Sea stars hunt mussels and urchins in shallow pools, while seals, sea lions, and sea otters inhabit kelp beds, feeding on the small creatures that graze there.

The park was designated as a protected area by President Theodore Roosevelt over a hundred years ago. Since then, it has been maintained naturally by the various creatures that live there without human intervention. Each has their role to play in this biodiverse ecosystem.

The two sisters talk about how important singing was for them growing up and Sylvia sings a little bit, too. This is their final appearance together on video before Sigrid's departure the next day.

Having arrived at their spawning grounds, several male coho try out different techniques to impress a single female. The river otters love fish, and need to eat a lot of them to maintain their active lifestyle.

As the orcas celebrate the success of their hunt, silver salmon, or “coho” are moving from the sea to the inland streams where they will breed. But they‘ll have to be careful and lucky too, as otters and black bears are waiting along the way.