pushing out of the dock of a boat called capelinSandy Milner’s small team of scientists head north, making their way through patchy fog and past a giant cruise ship. capelin As you slowly run through the humpback feeding grounds, a distant plume of exhalation rises from the water on this calm July morning. Dozens of sea otters dot the water. Some have babies in their arms, but they turn their heads curiously as the boat speeds past. Seabirds and seals spot the floating icebergs in the serene expanse of Alaska’s Glacier Bay.
After about two hours, the ship reaches the rocky shores where Wolf Point Creek meets the sea. Creeks are a relatively new feature in the landscape. Melting and retreating glaciers first freed estuary lands from ice in the 1940s. Fed by mountain lakes that slowly formed as isolated masses of glacial ice slowly melted, they took shape throughout the 1970s. Wolf Point Creek has undergone nearly its entire life, from the first sparse rivulets melting beneath the ice rim to a mature stream ecosystem teeming with aquatic life, from tiny chironomid larvae to tiny fish. Special. Edge — is well known and its history has been carefully documented.
Milner, a river ecologist at the University of Birmingham in the UK, has visited the site almost annually since the 1970s to catalog how life, especially aquatic invertebrates, arrived, flourished and changed over time. . He observed a few midges in his 1977 and in 1989 he came here to spot 100 pink his salmon.
The stream now supports all kinds of creatures that live off its abundance, from small algae to midges, salmon and their predators. is. A National Park Service boat with his captain, Justin Smith, idling the motors and preparing to land the crew. Sweeping the crescent coastline left to right with his binoculars, he stops, points across the beach and announces, “There she is.” Perhaps 500 meters from her, a giant sandy brown head munches on her tall grass and three dark brown cubs scurry at her feet.
“Do you still want me to drop you off?” Smith asks. Milner nods and expresses agreement. The wader-clad crew disembarks in shallow water and heads for the beach.
This place where Wolf Point Creek meets Muir Cove is a dynamic place. Once completely ice-bound, Muir Cove is now more than 20 miles long. The cove, at least for now, is part of a much larger glacier bay that boasts over 1,000 glaciers. Over the past 200 years, glaciers here have retreated rapidly as the planet warms. Alaska’s glaciers are shrinking the fastest on Earth, making this place a natural laboratory for ecologists.
How will ecosystems change? Melting glaciers put the science of ecological succession in the spotlight. It is the name given to the pattern of successive arrivals of species as they emerge in previously lifeless habitats. There is a longstanding ecological debate about inheritance that research by Milner and others may help resolve.
And how will salmon adapt? Wild salmon are known for their homing instinct, but not all return to the rivers of their birth. This is important in warm climates. Stray fish can settle in new rivers that form where glaciers have melted for a long time. As the streams, traditional salmon spawning grounds in the south, become increasingly inhospitable in temperate waters, some fish are actually dispersing to new areas, filling new niches that have opened up.
New rivers also create challenges, including for indigenous peoples who rely heavily on salmon for their livelihoods. Some have found salmon migrating to spawn in areas unprotected from development. May be excluded from fishing access to habitat.
