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John Pennekamp State Park

A cache by Jakesnake12013 & USFDad12013 Send Message to Owner Message this owner
Hidden : 6/27/2010
In Florida, United States
2 out of 5
1.5 out of 5

Size: Size: not chosen (not chosen)

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Geocache Description:

What makes the coral reefs of the Florida Keys so special? Well,
for starters, the Florida Keys Reef Tract is the only living coral
barrier reef in North America, and is the 3rd largest coral barrier
reef in the world (after the Great Barrier Reef in Australia and
the Meso-American Reef in Belieze). The reef runs roughly 221 miles
down the south-eastern coast of Florida, paralleling the Florida
Keys from Key Biscayne off Miami down to the Dry Tortugas, 70 miles
west of Key West, from 1 mile to 8 miles offshore. The proximity of
the reef (just a half-hour boat ride from land); the warm, clear
water from the Gulf Stream just offshore; and the fantastic
richness of life found here makes the reefs of the Florida Keys one
of the most uniquely beautiful and accessible wild areas in the
country. Unfortunately, many visitors to the Keys come down with no real understanding of what a coral reef is!

REEF is a general term
usually referring to a relatively shallow area of hard structure
that tends to attract animals. ALGAE REEFS are found in many areas
in the South Pacific, where the primary structure is calcareous
algae; ROCK REEFS are common in the Northeastern U.S., where
accumulations of granite or other rocky outcroppings have gathered
a variety of biofouling organisms and fish to form an active
hardbottom community; in many areas, people have even sunk concrete
structures, old ships, or railroad cars to form ARTIFICIAL REEFS,
which are rapidly colonized by various types of fish and fouling
organisms (ex., sponges, tube worms, and hard and soft corals).
CORAL REEFS are special because of the community of organisms that
build the reef, the HARD and SOFT CORALS. Corals are animals in the
Phylum Cnidaria (the group of animals that includes jellyfish and
sea anemeones), Class Anthozoa. Corals are found in a variety of
forms, from the hard branches of Elkhorn Coral to the soft
leaf-like structures of Sea Fans. Corals can generally be divided
into SOFT CORALS (Subclass Octocorallia), which have a soft,
flexible skeleton of protein (similar to what makes up human
fingernails or hair); and HARD CORALS (Subclass Zoantharia, Order
Scleractinia), which form a hard exoskeleton of secreted calcium
carbonate (limestone). Since the hard corals have a skeleton that
is literally rock, it is their growth that really forms the
structure of the reef. Each coral head is really a colony of
thousands of individual animals called CORAL POLYPS, which look
something like upside-down jellyfish. Many who are viewing corals
for the first time are surprised at their classification as animals
rather than plants, but a closer look clearly reveals
actively-moving tentacles and a central mouth, under which lies the
simplified digestive tract. Most of these little animals are only
around the size of the head of a pin, and are rarely larger than a
pencil eraser, but the coral colonies that they form can be the
size of a small house! Each coral polyp lives on the outside of the
coral head, in a cup or groove in the limestone skeleton. As the
coral colony grows and new polyps form through the division of old
polyps, each individual coral polyp will lift itself up off the
floor of its old cup and will secrete a new calcium carbonate floor
underneath it, causing the entire coral head to expand up and
outwards. A cross-section of a coral head clearly shows the
successive layers formed by each polyp’s growth and expansion
outwards. As the polyps move outwards, they leave behind them a
dead limestone skeleton, so the only living part on any coral head
is the outer 2-3 millimeters.

Most hard corals in the Keys grow at
a rate of 1/4 - 1/2 inch a year, and it ends up taking about 50
years for a brain coral to grow to the size of a basketball.
Branching corals (such as the hard coral Acropora cervicornis,
Staghorn Coral) grow somewhat faster, up to 1 1/2 inches a year,
but at the price of being much more brittle and prone to damage
from storms, ship groundings, or careless divers. Since the soft,
jellyfish-like outer layer is the only living part of any coral
head, a diver or snorkeler can easily damage or kill a coral merely
by touching it! This is the reason behind the Sanctuary
Preservation Areas, better known as "No Touch, No Take" Zones. The
polyps of hard corals get most of their nutrition from the sun!

Each hard coral polyp has within it many single-celled plants,
algae called ZOOXANTHELLAE, which give the coral its color (coral
tissue itself is completely colorless). The polyps use these
zooxanthellae to make most of their food through photosynthesis
(each algal cell makes much more food than it needs, and releases
the excess food to the coral polyp through oil droplets, a process
called "blebbing"); and the rest of their diet comes from active
feeding on a mixture of microorganisms suspended in the water
colony (phytoplankton and zooplankton). Because of this feeding
strategy, hard corals must have clear, shallow water to grow, so
that they can get enough sunlight to remain healthy. Corals also
tend to be very temperature sensitive, and when the water
temperature drops below 68 F or rises above 86 F, the
coral-zooxanthellae relationship breaks down (a process called
CORAL BLEACHING, because the coral colony turns white) and the
coral colony will usually starve and die. Coral’s sedentary
lifestyle also requires very high water quality, with a constant
flow of new nutrients and dissolved oxygen over the reef.

Unfortunately, these very specific conditions only occur in a few
places on earth, which is the reason that coral reefs only make up
0.5% of the world’s oceans! Many coral reefs can easily be
classified into one of various types. BARRIER REEFS are those that
are found some distance offshore following a shoreline and that
come nearly to the surface of the water; these reefs are so named
because they tend to form a barrier between the open ocean and the
land, and usually cause waves to break on the outside of the reef,
leaving a more sheltered area (usually called a LAGOON) behind
them. FRINGING REEFS also parallel the shoreline, but closely,
often without any lagoon area behind them; in some areas, fringing
reefs may grow right up the slope of an island to the low tide
mark. BANK REEFS are found offshore, but usually are at a greater
distance (frequently open ocean) and are associated with a spot
where the bottom raises up from greater surrounding depth; these
reefs rarely come as close to the surface and have no protected
lagoon. Some open ocean reefs are circular and enclose a shallow
lagoon; these are known as ATOLL REEFS, and are often associated
with extinct volcanic cones that have subsided below the
ocean’s surface. PATCH REEFS are exactly what they sound
like: small patchy areas of reef growth, ranging from a few coral
heads up to several square miles of coral cover, that are found at
various distances offshore and are separated by sand flats and
seagrass beds. The reefs of the Florida Keys usually span several
of these categories.

The only reef type not found in the Keys is
the atoll! True fringing reefs are rare in the Keys, and are found
almost exclusively in the Dry Tortugas, which means that you must
take a boat ride if you wish to see the reef. However, the outer
reef tract is much closer to shore than many barrier reefs,
becoming almost a "fringing barrier reef"; the outer patch reefs
are often closer to bank reefs, with the deep water surrounding
them, whereas several of the inshore patch reefs are fantastic
miniature models of a barrier reef, complete with the protected
lagoon area behind them. Although this tends to drive coral
researchers to distraction, snorkelers and divers greatly benefit;
the Keys provide some of the most unique snorkeling and diving
opportunities in the world! The reef system can also be categorized
by "relief," the height that the coral ridges reach above the sand,
and once again the Florida Key Reef Tract astounds with its
variety. Several inshore reefs are very low-relief and shallow,
with the coral growing as a carpet along the bottom and the fish
hovering over the top, fantastic for novice snorkelers; other
offshore reefs are high-relief, and divers will find themselves
cruising down coral canyons surrounded by schools of multicolored
wrasses and parrotfish. The depth ranges greatly as well. Several
of the inshore reefs have sections that stick out of the water at
low tide (these frequently have names ending in "Rocks"). Offshore,
the depth ranges from 15 down to 60 or 70 feet over the reef, and
if that isn’t deep enough for you, there are several
fantastic shipwrecks that have been put down as artificial reefs
outside the reef tract; many of these are right at the limits of
recreational scuba diving, and most are covered with soft and hard
coral growth, multicolored sponges, and schools of large fish.

Although the state park waters extend out from shore to the 3-mile
limit (this was the first underwater park of any kind in North
America!), the majority of the reefs off Key Largo were ceded over
to the Key Largo National Marine Sanctuary in 1975, which was then
incorporated into the Florida Keys National Marine Sanctuary in
1990. As a result, the reefs that we visit are now under heavier
protection (with heavier enforcement of violations!), and are
already showing great benefits from this protection! Many of the
most sensitive, healthiest reefs are now protected as Sanctuary
Preservation Areas, a designation that was put in place July 1st,
1997, to provide additional protection for those areas by making it
illegal to fish, lobster, stand, anchor on the reef, or even touch
anything within the SPA boundaries. This protection has boosted
levels of large gamefish on the reefs and greatly stabilized the
overall health of the reef tract while still allowing for
eco-tourism activities.

Please do your part to protect the reefs
when you visit the state park! Respect the boundaries of the SPAs
when fishing. Do not stand up on reefs or touch anything while
snorkeling or scuba diving.

To claim credit for this Earthcache
please answer the following questions and email them to the CO
prior to logging the cache. You do not have to wait for approval to
log after you have sent in your answers... but if your answers are
not correct your log may be deleted.

1. Based on the Reef information above... What type of Reef is represented here?

2. How many types of Reef Fish have been seen here on the reef? (poster)

3. What man-made additions have been placed on the reef just off
shore? How many are there?

4. There is a sample of the man-made addition (Question 3) located at GZ. How long is it? Take a picture of
yourself with your GPS on this object and email it to the CO at

Additional Hints (Decrypt)

Gur nafjref sbe nyy gur dhrfgvbaf ner ba gur Xvbfx

Decryption Key


(letter above equals below, and vice versa)



569 Logged Visits

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Current Time:
Last Updated: on 9/6/2017 3:45:33 PM Pacific Daylight Time (10:45 PM GMT)
Rendered From:Unknown
Coordinates are in the WGS84 datum

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