Dive Time with Tim Grollimund

The foundation of the reef

May 23, 2013 

The benthic (bottom) layer of the sanctuary is diverse and contains the building blocks of the ecosystem. (Photos by Tim Grollimund)

Last year I bought a house. It’s an old house that needs a lot of work. If I hadn’t bought it when I did, I’m sure it would have been condemned by now. I have a comfortable space with my office, kitchen and big screen for baseball games. I’ll get the repair work done over time. I’m a simple guy, so none of the sub par stuff bothers me.

When I bought the house, I got a good deal because of the condition (Realtors like to call it “as is”). I hired an inspector to check it out. He told me everything that needed attention, and I built my priority repair list from his report. A new roof and a remodeled kitchen — the essentials — are in place. A major reason I bought the house, however, was because the inspector said it had a good foundation, and it was structurally sound.

What does that have to do with underwater stuff?

According to Dr. Steven Miller of NOVA Southeastern University, a lot. He has been studying the benthic (bottom) layer of the Florida Keys for a very long time. At our last Working Group meeting he was one of the speakers. His topic was benthic communities and marine zoning.

Yep, another layer on the map. And this one, literally, is the bedrock of the reef system. See his research summary here: http://floridakeys.noaa.gov/scisummaries/elkhornstaghorn2013.pdf

The day before I interviewed him he sent me a mountain of research, about 200 pages worth of science. I missed the baseball game that night. I got through all the shorter papers, and the summaries of the larger works. It was well worth the effort. His research examines differences in reef structure and type throughout the Keys, and differences in zones, like no-take zones. He is the benthos census taker of the Keys.

We had a great conversation about how that bottom layer stacks up with all the other layers the working groups are examining.

One of the things we discussed is the good news in the benthic census. Many mid-channel and nearshore patch reefs are healthy — as much as 25 percent coral cover — well above the 5 or 6 percent seen on the most popular named reefs.

His thoughts on the good condition of these patches goes something like this: the patches deal with more environmental variability than their offshore counterparts, like greater temperature changes, wider ranges in water quality, and higher variances in turbidity. Perhaps they have adapted to be more resistant to these variables, and perhaps they have not been hit as hard as the offshore areas by other events, like storms, disease, fishing pressure and divers.

Another part of the conversation centered on how this layer is intertwined with the other layers, like spawning aggregations and connectivity. And there are changes taking place. As coral cover on some areas is declining, other species, like sponges, are taking over. Does the future of the reef point towards more soft coral and sponges if the hard, head and branching corals continue to decline? And how will, or could, that affect the spawning aggregations, connectivity and other essential ecosystem elements?

For the marine zoning and review process, identifying candidate areas for protection based on the coral cover, diversity, sponge cover and other measures from the studies is an important part of the process. We know where the areas are, and with more time to study them, we will gain insight as to why they are the healthier portions of the Keys, and perhaps what areas will change next.

When the SPAs were initially drawn in the 1990s — which were, at times, characterized by intense user conflict — parity among competing uses was an important driver. Demonstrative positive observations began to be recorded of the effect of no-take zones on the health and vitality of the entire ecosystem. Inclusion of a wider spectrum of habitat types associated with multiple species in the protected area seemed indicated. Dr. Miller points out that any management system really does not manage the resource itself. Regulatory systems manage the interaction people have on the system.

The ultimate management model is simple in theory, but difficult in the real world. According to Dr. Miller, “deciding on the biggest slice of space for the most meaningful ecosystem protection, while not adversely affecting the economic structure of the region is a trade off, a balancing act, where protection and conservation are in compromise with socio-economic drivers.”

I studied the California process. And it reiterates his point. They balanced what they could. All the competing interests had a say in the process. To me the value of that process is they identified what, where and how far apart the zones needed to be based on the best available science. The California case is a very interesting read. See the special issue of Ocean and Coastal Management covering this experience here: http://www.sciencedirect.com/science/journal/09645691/74/supp/C

In terms of the sanctuary, I believe we will apply the information the inspectors [scientists] bring us, identify the best foundational sites, put the essentials in place and build on that as resources allow. We will incorporate decision making tools to help in the process.

We have to get the foundation right first, and we can prioritize from there. Protection of the entire range of appropriate and necessary habitats that yield the highest probabilities for healthy a benthos, connectivity and spawning will be the furniture that fills the rooms.

As always, these are my thoughts, and are not the official views of the agencies with oversight of the sanctuary.

Tim Grollimund is a freelance photographer and PADI divemaster based in Key Largo. He can be reached at tim@timgimages.com or through his web site at www.timgimages.com. Tim is a member of the Ecosystem Protection Working Group for the Florida Keys National Marine Sanctuary Advisory Council.

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