Coral Reef Presentation
I am an avid snorkeler and soon to be open water diver and I am completely consumed by
my love of the ocean. Actually, that’s one of the reasons we moved to Florida.
A few weeks ago I had the opportunity to snorkel at John Pennekamp Coral Reef State
Park in Key Largo and this is pretty much what I saw. Corals with vibrant colors,
amazing species diversification, clear water and healthy plant life. It was an absolutely
fascinating and enjoyable experience
Unfortunately, all too many of the oceans reefs are beginning to look like this – the corals
are bleached, preyed upon, broken and dead. Seeing this dismal display is not quite the
uplifting experience that a vibrant reef offers.
Here is a small example of what is happening to our reefs. This is an image taken by Dr.
Phillip Dusten of Carysfort Reef in 1975. It shows a healthy outcrop of elkhorn coral.
Unfortunately, when he returned in 1985 to photograph this exact same location, this is
what his eyes beheld. The entire bed of coral was decimated. Sometime during the
interval between these two pictures a boat had run aground on the coral bed, totally
destroying the coral (I don’t imagine the boat fared to well either). What makes the
situation even worse is that when he again returned in 1995, the coral showed no signs of
improvement or regrowth. It lacked the robustness and conditions required to heal its’
self. The only evidence of life was an overgrowth of filamentous algae. This is one
isolated image, but it’s not an isolated event.
Let’s first spend a little time discussing the importance of coral reefs other than their
aesthetic value
Reefs are undeniably the densest and most biodiverse environment on earth and are the
rainforests of the marine ecosystem. They directly provide the necessary habitat for over
25% of all marine life and serve as the basis for the entire oceanic food chain.
And what’s truly amazing, they doing this while covering only 0.07-0.2% of the ocean
floor. To put that in perspective, assume that the floor of this room is the area covered by
all the oceans in the world. The area that is occupied by all the reefs would be equal to
an area about the size of your foot.
There are some very disturbing statistics out there concerning the future of reefs. 27% of
reefs are currently classified as dead and are showing no signs of regeneration. 60% of
the remaining worldwide reefs are at serious risk and 32% could be lost within the next
20 years. The most alarming statistic is that in as little as 50 years all natural coral reefs
could be dead. That certainly doesn’t paint a pretty picture for the health of our oceans.
On a more local level, let’s take a closer look at Florida reefs. They stretch from around
the Miami area down to the very tip of the Keys and they truly are a state treasure.
Unfortunately, if we look at the reefs that are in the Caribbean, it quickly becomes
evident that the picture of reef health is pretty dismal. About the only reefs that are doing
okay are those that are fairly far offshore. And what about our own reefs, how are they
fairing – not much better. A few are okay, most are at moderate risk and some are at high
risk.
So, what’s threatening our reefs? :
There are a number of natural threats that the reefs are facing: Disease, Predators,
Weather events, bleaching. With the exception of aspergillosis (more on that later), these
are threats that reefs have faced for centuries and have stood their ground and survived
the assault. However, giving the onslaught of new environmental stressors, that is no
longer exactly true
Man has exponentially compounded stress induced to reefs. Some of these stressors are
somewhat localized and include – as demonstrated in the images from Carysfort Reef,
Fishing practices, or lack there of – overfishing, the use explosives that not only kills fish,
but turns vibrant reefs into rubble, poisoning – basically dumping of cyanide in to water,
poisoning all living things in the area. Collecting – coral mining – visit any of the shell
shops that are strewn up and down the coast and the shelves will be full of dead coral.
Did ya ever wonder where they got all these specimens? They were harvested form living
reefs, dried and bleach and put on display. Marine aquariums have become very popular
and one of the reasons is the beautiful assortment of fish that can be added to the
collection. Well, just like the coral, these fish are harvested form living reefs. Very few
of these gorgeous creatures can successfully be bred in captivity.
Dives/snorkelers, either purposely or inadvertently can damage the fragile coral of the
reef – harvesting, standing, accidentally brushing up against the fragile polyps all cause
damage.
Onshore – the removal of mangrove swamps. This is done for a couple of reasons –
make more usable land to build on or mariculture. Those cheap farm raised shrimp that
you buy at the local grocery store – there is a good chance that they were raised in an area
that used to be a thriving mangrove swamp. There are negative effects with the removal
with the remove of these ecosystems. 1) Remove the nursery for a number of reef
species 2) allow terrestrial runoff to flow directly onto the oceans. Mangroves help
establish a buffer zone that prevents this from happening
Let’s take a look at a few global events that are negatively affecting the reefs.
Silting – with all the coastal development worldwide, there is little to prevent soil ladened
runoff from flowing into the sea. Silting clouds the water and directly contributes to the
spread of aspergillosis. Aspergilla are bacteria that normally reside in the soil. It
basically hitches a ride with the soil particles, settles on the coral and starts to establish
colonies that interfere with the normal balance of the ecosystem. Fertilizers and effluent
both add unnatural levels of nutrients which can throw the delicate balance required by
the coral off kilter. They encourage the growth of algae, which can overwhelm the coral
and in essence, smother it. Industrial pollution – heavy metals, toxins, petroleum based
products all add additional stress to reef, not to mention that it’s not so healthy for people
that are surviving of the reef. Global warming is also devastating for the reefs. It
increases the sea temperature and the sea depth, both of which increase coral stress.
Communities worldwide are aware of the potential fate of our reefs and are trying to at
least slow down the process. It just so happens that 2008 has been declared the year of
the reef. One of the main goals of this declaration is to educate and increase awareness of
the reef environment Bush – marine sanctuary off Hawaii, International Coral Reef
Initiative – partnership between governments, international organizations that is designed
to preserve coral reefs and their unique ecosystems.
At this point, you may be asking yourself – what can I do? Educate yourselves and your
friends. If you’re boaters, know what’s beneath you when you drop anchor. Study your
navigational charts and avoid plowing into a reef. If you dive or snorkel, use reef
friendly practices and be aware of your surroundings so you do no harm. Reduce your
carbon foot print. Become an informed consumer. Become active in reef preservation
and protection organizations. Check out any of these sites for more ideas on how you can
help.