This is an EarthCache and you MUST complete the educational portion in order to log this cache. The terrain rating is 2.5 due to almost 2 miles of walking/hiking activity so bring your comfortable shoes and plenty of water. This is Florida so bring bug spray and be careful of the wildlife.
Bring a measuring tape to complete Stage 1 of the educational tasks.
About the park: The Guana Tolomato Matanzas National Estuarine Research Reserve encompasses approximately 73,352 acres of salt marsh and mangrove tidal wetlands, oyster bars, estuarine lagoons, upland habitat and offshore seas in Northeast Florida. The GTM Reserve is located in the East Florida subregion, south of Jacksonville and sandwiching St. Augustine. It contains the northernmost extent of mangrove habitat on the east coast of the United States, some of the highest dunes in Florida, measuring 30-40 feet, and one of the few remaining "inlets" in northeast Florida not protected by a jetty thus presenting an easy study of what an inlet might have looked like in the past. The coastal waters of the GTM Reserve are also important calving grounds for the endangered Right Whale.
Fees are:$3.00 per vehicle up to 8 people. $1.00 per Pedestrians, Bicyclists, Extra Passengers in vehicle beyond 8 to this area of the GMT recreation. The Reserve is open all year. The hiking trails are opened from 8:00 AM to SUNSET.
Recreational Activities that can be enjoyed at the GMT
- Beach-going.
- Bicycling.
- Birding and other wildlife viewing.
- Boating.
- Camping.
- Canoeing/kayaking.
- Fishing.
- Hiking.
- Horseback riding.
- Picnicking.
You are encouraged to visit the GTM Research Reserve’s Environmental Education Center to learn more about the Reserve. The center provides a one-of-a-kind opportunity for people of all ages to learn about the many functions of the coastal and estuarine ecosystem and the natural history of Northeast Florida. Staff-led programs are offered to school teachers, students (high school, college, and 7th grade LIFE program with partner schools), adults and environmental professionals. Volunteer-led programs are offered to 4th grade students. Other grade levels can participate on a self-guided visit or a guided tour by a GTM Research Reserve volunteer if available. Other programs at the center include Coastal Science Seminars, brown bag lunch programs on the first Friday of the month, guided walks, and nature movies on the weekends. Please call (904) 823-4500 for a list of special events and guided walks. Admission Fee to the Environmental Education Center is Adults $2.00, Children (10-17) $1.00, Children under 10 - Free. The Center is open from 9:00 AM to 4:00 PM (Closed on state holidays)
While at GMT you will be on marked trails so please stay in them. You will be going on a hiking journey to the Freshwater Marsh.
A marsh is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss. A marsh is different from a swamp, which has a greater proportion of open water surface and may be deeper than a marsh. The freshwater marsh relies on rainfall for its water. This is in contrast to the saltwater marsh which relies on the tides.
Wait a minute! You are talking about marshes but this EarthCache name is: Coastal interdunal swale at GMT. All right! Coastal interdunal swales are marshes, moist grasslands, dense shrubs, or damp flats in linear depressions formed between successive dune ridges as sandy barrier islands, capes, or beach plains build seaward. In the case of the GMT the coastal interdunal swales is a dune and swale topography where groundwater intersects with the bottom of the swale and saltwater flooding is infrequent.
So... What is a swale? A swale is a low tract of land, especially one that is moist or marshy. The term can refer to a natural landscape feature or a human-created one. Artificial swales are often designed to manage water runoff, filter pollutants, and increase rainwater infiltration. Dunes are sandy hills built by wind.
Coastal interdunal swales are found along sandy coastlines in Florida, principally along the Gulf coast and the northeast Atlantic coast south to Cape Canaveral. The community varies from flooded to completely dry depending on rainfall, as well as on height and area of the surrounding dunes.
Near N30° 01.284 W81° 20.164 the GTM Research Reserve created a "low-water crossing" that allows for water to flow freely any time the water level rises. Previously the water flow was obstructed by an elaborate network of mosquito ditches that were dug along a component of the Guana peninsula. Associated spoil piles and berms caused a serious decline in water levels by impeding the natural water flow in this region. Also, a roadway added to the problem by dividing the marsh.
The GTM Research Reserve completely removed the center of the roadway and layed down layers of an expandable, stabilizing grid on the marsh bottom. The grid, called a geoweb, was covered with gravel to hold the sediment in place. Fresh water is now able to flow freely throughout the reserve's marsh. During dry spells, reserve vehicles are still able to cross over the gravel bottom. This trail is now used primarily for recreational hiking. The rangers at the reserve built a wooden boardwalk spanning the entire marsh to allow hikers to cross the marsh at any water level.
Now to test your learning experience:
Stage 1. Interdunal Swale. Go to the following coordinates N30° 01.284 W81° 20.164
Answer the following questions:
S1-1. Using your GPSr determine the width of the marsh at this location?
S1-2. I hope you brought the measuring tape. Right! What is the elevation difference from the top of the boardwalk in relation to the bottom of the swale? If you forgot, indicate the number of steps on the west side of the boardwalk.
Stage 2 Freshwater Marsh. Go to N30° 01.345 W81° 20.269 and Answer the following questions:
S2-1. Why are you standing on a board walk?
S2-2. Describe the conditions at the marsh. Is the marsh wet or dry?
As optional additional logging requirements (ALR) post a photo of you and your GPSr in your favorite location. You are welcome to post additional photos of your visit to the GTM. Please do not post photos that would give away the answers to any of the educational portion of this cache (stages 1 and 2). Logs with photos that provide the required answers to the questions will be deleted.
Email me the answers to the questions for Stages 1 and 2 to the address on my profile: Click here.
While you are visiting GTM can also get the following caches:
GTM Reserve Cache - GCYQ81
Guana Backwoods - GC1Y6TV
"cache with a view" - GC108NV
Additional websites:
The Friends Of The GTM Reserve
Guana Tolomato Matanzas National Estuarine Research Reserve is part of The National Estuarine Research Reserve System
Sources:
GTM Trail Map
GTM Website
Wikipedia - Dune
Wikipedia - Marsh
Wikipedia - Swale
Wikipedia - Tidal Marsh
Thanks to Guana Tolomato Matanzas National Estuarine Research Reserve for allowing the placement of this cache.
Revised 2011-02-24 for entrance fee to this area.