The last destination on our Alaskan journey was the Kenai Peninsula and the town of Seward. After a few days respite from the wildfire smoke in Wrangell-St. Elias, it returned with a vengeance as we headed back to Anchorage and down to the the coast:
After baking in the heat of the Alaskan interior for the last week, the marine climate of Seward was a welcome change. We even had a bit of rain for one of the few times in our entire trip.
While temperatures in Seward we’re somewhat more mild, the coastal location meant the humidity was not. On our first day in Seward, we partook in a brutal hike up to the Harding Icefield in Kenai Fjords National Park. The hike itself was not abnormally difficult, but we were definitely not used to the combination of heat and humidity, leaving me feeling physically ill at several points during the slog up the mountain. The day had started off overcast, but as we climbed, the clouds evaporated leaving us with stellar views of the rapidly retreating Exit Glacier and the Harding Icefield from which it originates. An icefield is essentially a large mass of interconnecting glaciers. The Harding Icefield is the largest — and one of only four — remaining icefields in the United States. The Exit Glacier itself has retreated more than a mile in the last 200 years, leaving trees and other vegetation to begin re-occupying it’s former valley.
The white and blue ice of the glacier made for a stellar contrast with the lush green vegetation of the alpine zone:
The wet climate of coastal Alaska results in extremely heavy snowfalls, making this one of only a handful of places in the world where glaciers flow all the way down to sea level to meet the ocean. Known as tidewater glaciers, these glaciers exhibit complex patterns of advance and retreat that, unlike standard alpine glaciers, are not purely the result of variations in climate. While warmer temperatures or prolonged drought can certainly reduce their mass, the movement of tidewater glaciers is also subject to complex interactions between the ice, the geomtery of the ocean floor, and the depth of the water into which they flow.
On our second day in Seward, we took a water taxi into the heart of Kenai Fjords National Park and then kayaked to within about a quarter mile of the terminus of Holgate Glacier. Tidewater glaciers have a tendency to “calve”, in which large chunks of ice break off the glacier and fall into the ocean, necessitating a safe distance. Glacier “social distancing” if you will. It is not hard to find videos on YouTube of people getting too close to calving tidewater glaciers, with quite predictable results. From our safe distance, we observed and heard several calving events in the few hours we were kayaking around the bay, but unfortunately I was not adept enough at kayaking into position quickly enough to actually capture one on camera.
Our boat ride back to Seward through Resurrection Bay also resulted in sightings of sea lions, seals, puffins, and even two pods of orcas: an exciting end to the trip!
Up until a few days ago, I would have felt extremely confident saying that I’ve seen more fossilized sea snails in my life than I have real ones. After all, teaching a lab that revolves around sedimentary rocks for two quarters will put one in close contact with more dead gastropods than one ever thought possible. And when you spend a lot of time staring at multi-million-year-old fossils, it’s often easy to forget that lots of the little buggers have closely related relatives still trolling the high seas today.Just a few of the many, many, MANY different colored and patterned varieties of nucella lamellosa, the Frilled Dogwinkle
A few days ago though, I stumbled upon a sea snail breeding ground of epic proportions at a place called Point Whitehorn Marine Reserve. I had gone there with the express purpose of looking at rocks and I remain convinced that the snails made their dramatic appearance in order to force me to confront the inherent irony in going to a marine reserve to look at rocks. Near the low-tide line, a couple of bright orange striped shells grabbed my attention, sticking out marine creamsicles amidst the backdrop of drab green algae and seaweed, dull brown barnacles, and grey sky reflected in the waves. I soon realized that I was surrounded (in a benign and not even remotely threatening way) by hundreds upon hundreds of sea snails exhibiting a dazzling array of different colors and patterns.
Now, my knowledge of sea snail taxonomy is limited, but it appears that despite the disparate appearance of these snails, they are all part of the same species: nucella lamellosa, also known as the Frilled Dogwinkle or Frilled Whelk (if anyone has information to the contrary, please let me know). Most of the snails in these photos are smooth; they have lost their ridges or frills that normally run along the length of their shell. This is apparently a common fate of nucella lamellosa that choose to spend their lives in places like Pt. Whitehorn which experience very rough surf during the winter. The frills literally get worn away, not at all surprising when you consider that the shells are made out of calcium carbonate, a substance that in it’s crystalline form is only a we bit harder than drywall.
Many rocks were encrusted with dozens of the snails, varying in size from babies barely larger than a pea, to a few gargantuan snails nearly four inches long. This species hatches in late winter and early spring, so this is a good time to get a sneak peak at the next generation. A female sea snail can apparently lay thousands of eggs each year, although like most species who opt for quantity over quality when it comes to reproduction, only a small percentage survive to adulthood. In the case of nucella lamellosa, that number is estimated at a paltry 1%. Upon reading this, I realized in horror that the occasional sharp “crunch” heard from underneath my boots while I was taking these photographs was nothing other than the sound of my contribution to this rather depressing and morbid statistic. But with any luck, those shell fragments I (inadvertently) created will get weathered, transported, buried, and fossilized, eventually re-surfacing in the collection of some enterprising geologist a few million years from now, a fate that can only be described as THE ultimate honor for any ambitious gastropod.