The Mary E. Theler Exhibit Building, located at the Hood Canal
Watershed Project Center near the trailhead, offers hands-on
interactive displays and educational exhibits. It depends on
volunteers to keep it open from 11 am - 3 pm on weekends and
holidays, so there is no guarantee the building will be open on
those days. Look for the "open" sign as you are walking by.
Four separate trails are open to the public free of charge
during daylight hours, seven days a week. Sorry, but your pets are
not permitted on the wetlands trails.
The Hood Canal and its tidal shorelines
The Hood Canal is the only salt water fjord in the lower United
States. It was created about 13,000 years ago, during the Late
Pleistocene, by the western lobe of the Cordilleran Ice Sheet
called the Puget Lobe. This ice sheet covered a vast part of North
America, to include Washington, Idaho, and Montana. When it
retreated, it left behind deposits and erosional landforms.
About 1100 years ago, there was a sudden uplift in this section
of the Hood Canal. Prior to this, the area was mostly a mudflat
that was exposed during normal low tides. The sudden uplift was
accompanied by a tsunami, a huge surge of water and soil that
covered the ancient mudflat above the reach of the tides. Plants
grew and eventually decomposed to form layers of peat. The presence
of abundant wood, and diatoms, seeds, and pollen in the basal layer
of peat are characteristic of moist upland meadows, freshwater
marshes, and swamps and show that the peat formed above the highest
tides. A subsequent rise in relative sea level has led to the
formation of peat containing plant rhizomes and diatoms
characteristic of tidal salt marshes.
Tidal marshes, a type of wetland, can be found along protected
coastlines in middle and high latitudes worldwide. They are most
prevalent in the United States on the eastern coast from Maine to
Florida and continuing on to Louisiana and Texas along the Gulf of
Mexico. Some are freshwater marshes, others are brackish (somewhat
salty), and still others are saline (salty), but they are all
influenced by the motion of ocean tides. Tidal marshes are normally
categorized into two distinct zones; the lower or intertidal marsh,
and the upper or high marsh.
In saline tidal marshes, the lower marsh is normally covered and
exposed daily by the tide. It is predominantly covered by the tall
form of smooth cordgrass. The saline marsh is covered by water only
sporadically, and is characterized by short smooth cordgrass, spike
grass, and black grass. Saline marshes support a highly specialized
set of life adapted for saline conditions.
Tidal marshes serve many important functions. They buffer stormy
seas, slow shoreline erosion, and are able to absorb excess
nutrients before they reach the oceans and estuaries. High
concentrations of nutrients can cause oxygen levels low enough to
harm wildlife, such as the "Dead Zone" in the Gulf of Mexico.
Pressure to fill in these wetlands for coastal development has
lead to significant and continuing losses of tidal marshes,
especially along the Atlantic coast. Pollution, especially near
urban areas, also remains a serious threat to these ecosystems.
Fortunately, most states have enacted special laws to protect tidal
marshes, but much diligence is needed to assure that these
protective measures are actively enforced.
Information source:
http://www.eoearth.org/article/Tidal_marsh
http://riverhistory.ess.washington.edu/research/tidal_marshes.php
http://earthquake.usgs.gov/regional/pacnw/paleo/reports/lynchcov.php
http://vulcan.wr.usgs.gov/Glossary/Glaciers/IceSheets/description_ice_sheets.html
FINDING THIS CACHE:
To claim a find on this cache you must do the following:
- BEFORE logging your find, email me and tell me what you
see.
- As you walk to the given coordinates, take note and observe
what kind of marsh this is. Is it a lower or high marsh?
- Is it high tide or low tide and is the area covered by water or
not? Is the water salt or freshwater?
- How far did the glacier reach and did it cover this area? What
evidence suggests that this body of water was formed by a
glacier?
- To verify that you were there, include your estimation of the
distance to the open water in the Hood Canal.
- Log your find as soon as the answers to have been sent to
me.
- You may post a photo of yourself near the posted coordinates to
your log, but it is NOT required.
Important!! Send your answers and write your log at the same
time. EVERY CACHER LOGGING A FIND MUST SEND ANSWERS AT THE SAME
TIME AS THE FOUND LOG. No group answers. No exceptions. If I delete
your log, it will be due to a failure to follow this instruction.
You can then send the answers and re-post your find at the same
time.