Alaska Park Science Anchorage, Alaska

Alaska Park Science Anchorage, Alaska

National Park Service U.S. Department of Interior Alaska Support Office Alaska Park Science Anchorage, Alaska Scientific Studies in Kenai Fjords National Park Volume 3, Issue 1 Table of Contents Introduction __________________________________________ 3 Ecological Overview of Kenai Fjords National Park ____ 5 Harding Icefield’s Clues to Climate Change __________ 13 Lingering Mysteries of the 1964 Earthquake __________ 18 About the Authors Wandering Rocks in Kenai Fjords National park ______ 21 Peter J. Armato, Ph.D., is Director of the Jeffrey T. Freymueller, Ph.D., is an associate Live Feed Video Monitoring of Harbor Seals __________ 25 Ocean Alaska Science and Learning Center professor at the Geophysical Institute, Monitoring Nesting Success and an affiliated associate professor at the University of Alaska Fairbanks. of the Black Oystercatcher __________________________ 30 University of Alaska Fairbanks. Anne Hoover-Miller is a marine mammals The Ice Worm’s Secret ______________________________ 31 Shannon Atkinson, Ph.D., is Research Director biologist for the Alaska SeaLife Center. Connecting with the Past — The Kenai for the Alaska SeaLife Center and a professor Fjords Oral History and Archeology Project ____________ 33 at the University of Alaska Fairbanks. Gail V. Irvine, Ph.D., is an ecologist for the The Lowell Family and Alaska’s Fur Trade Industry: Alaska Science Center, U.S. Geological Survey. Seward, Alaska ______________________________________ 39 Sandy Brue is Chief of Interpretation for Kenai Fjords National Park. Russell Kucinski is a geologist for the Cover photograph © Page Spencer National Park Service, Alaska Region. Susan Campbell is a teacher in the Alaska Park Science Fairbanks Northstar Borough School District. Daniel H. Shain, Ph.D., is an assistant professor http://www.nps.gov/akso/AKScienceSpring2004.pdf in the Biology Department, Rutgers University. Editor: Monica Shah Anne D. Castellina is Superintendent of Page Spencer, Ph.D., is a landscape ecologist Copy Editor: Thetus Smith Kenai Fjords National Park. for the National Park Service, Alaska Region. Project Lead: Robert Winfree, Regional Science Advisor, email: [email protected] Aron L. Crowell, Ph.D., is an archeologist and Park Science Journal Board: Alaska Director of the Arctic Studies Center, Michael Tetreau is a resource management Ted Birkedal, Team Leader for Cultural Resources specialist for Kenai Fjords National Park. Don Callaway, Cultural Anthropologist National Museum of Natural History, Terry DeBruyn, Regional Wildlife Biologist Smithsonian Institution. Joy Geiselman, Deputy Chief, Virginia Valentine is a research Biological Science Office USGS Alaska Science Center technician for the Geophysical Institute, Russ Kucinski, Team Leader for Physical Resources Keith Echelmeyer is a professor of John Morris, Education Coordinator geophysics at the Geophysical Institute, University of Alaska Fairbanks. John Quinley, Assistant Regional Director for Communications University of Alaska Fairbanks. Jane Tranel, Public Affairs Specialist Sandra Zirnheld is a research Ralph Tingey, Associate Regional Director for Resources and Education Robert Winfree, Regional Science Advisor and Chair of Journal Board Anthony R. Fiorillo, Ph.D., is a curator at the technician for the Geophysical Institute, Funding provided by the National Park Service and other contributors Dallas Museum of Natural History. University of Alaska Fairbanks. Produced in cooperation with the Alaska Natural History Association Printed on recycled paper with soy based ink Printed in China 2 Ecological Overview of Kenai Fjords National Park Photograph ©Page Spencer By Page Spencer and Gail V. Irvine Plate Tectonics during the Holocene (Hamilton and Nelson Kenai Fjords National Park rides the 1989) (Figure 2). A dozen earthquakes of The major drivers of Kenai Fjords exposed edge of the North American plate magnitude 6.0 or greater have occurred in ecosystems are tectonics and climate. In where the Pacific plate is “diving” beneath the region during the past century this overview, we describe how these forces the North American plate. As crustal plates (Haeusser and Plafker 1995). The last great have contributed to the shaping of the have slowly moved northward, they have earthquake in southcentral Alaska, before lands and ecosystems of Kenai Fjords. brought parcels of land (terranes) that were 1964, occurred approximately 800 years Physically, the park is comprised of accreted onto the margin of the North ago (Mann and Crowell 1996). several distinct components, set within American plate in a series of deformed The epicenter of the 1964 Great Alaska a broader ecophysical framework that arcuate ridges and basins. These features Earthquake was 95 miles (150 km) north- includes the Kenai Peninsula and coastal form the present day Kenai and Chugach east of the town of Seward, and 100-150 Figure 2. Aerial view of the drowned cirques marine waters and islands. Squeezed Mountains and the Cook Inlet basin. miles (150-250 km) from the coast of Kenai of the Harris Peninsula. between the Gulf of Alaska and the Kenai Upper Jurassic and Cretaceous-aged rocks Fjords (see article by J. Freymueller, this Mountains, the coastal zone of the park is stretch from Kenai Fjords near Gore Point issue). Land deformation following the a narrow band of exposed headlands and through the Chugach Mountains as far east earthquake was distributed along a “hinge” deep fjords. The Harding Icefield caps the as Glacier Bay (Plafker et al. 1994). line of zero vertical motion that runs off- (Left) Figure 1. Landsat TM image of Kenai Kenai Mountains above the fjords with ice The park’s position on the junction of shore of Kenai Fjords. Subsidence occurred Fjords region. August 8 and July 26, 2000. estimated to be 3,000 feet (1,000 m) thick two crustal plates makes it prone to earth- to the northwest and uplift to the southeast Composited and enhanced by Michael Fleming, USGS. Design by Dave Allen, USFS. (Figure 1). Although not included in the quakes of moderate frequency and intensity, of this line. Additional coastal erosion was National Park Service jurisdiction, the park with resulting ocean floor landslides and caused by underwater landslides in the is ecologically linked to the offshore marine terrestrial uplift and subsidence. The beau- fine-grained silts and clays deposited by ecosystem, and the embedded offshore tiful circular bays of the Aialik, Harris, and glacial rivers at the head of Resurrection islands, most of which are part of the Alaska McCarty Peninsulas are drowned cirques Bay. Similar landslides (and tsunamis) may Maritime National Wildlife Refuge, man- of the Chugach Mountains, which were have occurred in Beauty Bay and North aged by the U.S. Fish and Wildlife Service. partially submerged by tectonic subsidence Arm of the McCarty Fjord at the western 5 Ecological Overview of Kenai Fjords National Park Photograph ©Page Spencer Warming and cooling cycles have More recent glaciations, although impres- resulted in multiple glacial advances sive in their impacts on the landscape, are mere whimpers in the scheme of glacial and retreats. Unlike many glacial cycles. The glaciers reached their last maxi- terrains where cooling trends reduce mum late in the nineteenth century and are summer melting, bringing on glacial currently undergoing a fairly dramatic retreat (Wiles and Calkin 1994). Nearly advances, the Kenai Fjords glaciers 40 outlet glaciers flow off the Harding move forward when warmer weather Icefield, seven of which terminate as tide- brings moisture-laden storms to the water glaciers in Aialik, Northwestern, and McCarty Fjords. Approximately 100 years coast. Air is rapidly forced over the ago, these fjords were filled with glaciers abrupt mountains and drops copious that rested on terminal moraines miles snowfall onto the Harding Icefield. seaward from their current termini (see article by Valentine et al., this issue). McCarty Glacier has retreated 14.5 miles (23 km), and Northwestern and its associ- ated glaciers have retreated more than 9 miles (15 km) since 1909 (Rice 1987). Figure 3. “Ghost forest”: Sitka spruce killed by saltwater intrusion onto land in Beauty Bay that subsided in the 1964 earthquake. The Harding Icefield is the largest of four permanent icefields in the Kenai Moun- end of the park. However, most of the fjords Most obvious, perhaps, is the effect of moisture-laden storms to the coast. Air is tains, covering approximately 700 square have very steep bedrock walls or tidewater climate on glaciation. Basic alteration of the rapidly forced over the abrupt mountains miles (1,800 km2). This flat cap of largely glaciers at their heads and lack sediment weather leads to changes in temperature and drops copious snowfall onto the stagnant ice blankets the mountains above buildups. Saltwater intrusion and tidal and precipitation, which affect snow pack Harding Icefield. 1,650 feet (500 m) (Wiles 1992). Scattered flooding following subsidence have con- formation and glacial movements. It also There have been at least four major gla- nunataks (Figure 4) rise above the icefield verted freshwater wetlands and spruce affects the freshwater contribution into the cial advances in southcentral Alaska during to 6,500 feet (2,000 m) on Truuli Peak, forest bands throughout the fjords to tidal coastal marine system, which coupled with the late Pleistocene and early Holocene the highest point on the Kenai Peninsula. marshes and “ghost forests” (Figure 3). wind, are primary forcers of the

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