What We Monitor

The Southwest Alaska Network uses long-term ecological monitoring to track changes in selected park resources and processes, called "vital signs." Monitoring these key resources helps us to understand the overall condition of park resources.

Freshwater Systems

  • Lake trout in a net.
    Freshwater Contaminants

    To understand freshwater contaminants, we monitor mercury levels in resident, non-migratory lake fish.

  • A researcher collects a water sample.
    Water Quality

    Water quality is an indicator of aquatic and terrestrial ecosystem health in Southwest Alaska.

  • A researcher measures lake characteristics.
    Water Quantity

    Lake levels affect how water integrates energy, nutrients, and pollutants from the landscape and atmosphere.

  • Bright red salmon in clear turquoise waters.

    Each year, millions of sockeye salmon return to Bristol Bay, infusing life into the culture, economy, and ecosystem at large.

Nearshore Marine Systems

  • Close up of a bed of kelp.
    Kelp and Eelgrass

    Kelps and eelgrasses provide understory and ground cover for planktivorous fish, clams, and urchins.

  • A researcher prepares instruments to measure ocean characteristics in the intertidal zone.
    Marine Water Chemistry

    Marine water chemistry, including temperature and salinity, are critical to intertidal fauna and flora.

  • A researcher surveys  mussels.
    Marine Intertidal Invertebrates

    Intertidal marine invertebrates are a food source for seabirds, marine mammals, and terrestrial carnivores, such as bears.

  • A puffin floats in the ocean.
    Marine Birds

    Marine birds are top-level consumers of marine invertebrates such as mussels, clams, snails, limpets, and forage fish.

  • A Black Oystercatcher on a rocky beach.
    Black Oystercatchers

    Black Oystercatchers provide a unique opportunity to view the nearshore zone from the perspective of an avian predator.

  • A sea otter floats looking attentive.
    Sea Otters

    Sea otters can dramatically affect the structure and complexity of their environment.

Terrestrial Systems

  • A Bald Eagle at the top of a tree.
    Bald Eagles

    Southwest Alaska parks support large populations of Bald Eagles.

  • Evidence of insects under tree bark.
    Insect Outbreaks

    A warmer climate is known to facilitate the growth of spruce beetle and spruce aphid populations.

  • A tidewater glacier.
    Glacial Extent

    Glaciers currently cover approximately one-eighth of Southwest Alaska parks.

  • Ice from break up piles on the shore.
    Seasonal Processes

    Seasonal processes are natural cycles such as lake ice formation and breakup or snowpack accumulation and melt.

  • A bear in a salt marsh.
    Sensitive Plant Communities

    Salt marshes are important habitat to many species and are sensitive to environmental changes.

  • Researchers measure plant communities.
    Vegetation Composition and Structure

    Vegetation drives ecosystem productivity, provides habitat and forage for wildlife, and food and materials for subsistence.

  • A group of visitors watch bears at the Brooks Falls platform in Katmai National Park and Preserve.
    Visitor Use

    Identifying where visitors go in our parks and what they do helps us maintain excellent visitor experiences and protect natural resources.

Weather, Climate, & Air Quality

  • A researcher maintains a weather station.
    Weather and Climate

    Weather and climate are key physical drivers of ecosystem structure and function.

  • A sunrise.
    Air Quality

    The air quality monitoring program has three primary components: visibility, atmospheric deposition, and gaseous pollutant monitoring.

Vital Signs On Hold

  • Sunrise lights the grasses along the beach.
    Geomorphic Coastal Change

    Changes in shoreline geomorphology affect coastal and nearshore habitats and the species that depend on them.

  • Two bear cubs on the beach.
    Brown Bears

    Brown bears play an important ecological role as top predators influencing population dynamics of other species.

  • A bull moose in the vegetation.

    Moose are an important subsistence and cultural resource to local Native Alaskans.

  • An aerial view of the landscape showing different vegetation cover and features.
    Land Cover Change

    Land cover change examines biophysical patterns on the landscape and how they change over time.

Last updated: May 3, 2018