Tag Archives: water filtration

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Researchers and Oystermen Fighting for Apalachicola Bay

Last week, Hanna Garland showed us how the Hughes/ Kimbro Lab adapted their techniques for underwater research in Apalachicola Bay. She talked about their difficulties with the weather, and as you can see in the video above, it was difficult for their oysterman collaborator (as it is for Apalachicola oystermen these days) to find enough healthy adult oysters to run the experiment. Below, David Kimbro looks back at the big Biogeographic Oyster study and what it has taught them about how oyster reefs work, and how they’ve been able to take that knowledge and apply it to the oyster fishery crisis.
Dr. David Kimbro Northeastern University/ FSU Coastal & Marine Lab

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Does our study of fear matter for problems like the Apalachicola Bay oyster fishery crash? Absolutely.

Bear with me for a few sentences…

I like to cook. My first real attempt was a chicken piccata and it was a disaster. After ripping off the recipe from my brother (good cook), I quickly realized that the complexity of the recipe was beyond me. To save time and fuss, I rationalized that the ordering of ingredients etc. didn’t matter because it was all going into the same dish. Well, my chicken piccata stunk and I definitely didn’t impress my dinner date.

Way back in 2010, David paddles to one of the St. Augustine sites used in the lab's first tile experiment. Since then they have done two spat tile experiments and two cage experiments ranging from Florida to North Carolina.

2010: David paddles to a St. Augustine oyster reef during his lab's first tile experiment. Since then they've done two spat tile experiments and two cage experiments ranging from Florida to North Carolina.

Around this same time… long, long ago, a bunch of friends and I were also working on a basic science recipe for understanding how oyster reefs work and it only contained a few ingredients: predatory fish frighten crabs and this fear protects oysters….a beautiful trophic cascade! But years later, we figured the recipe was too simple. So, we overhauled the recipe with many more ingredients and set about to test it from North Carolina to Florida with the scientific method.

Now that we finally digested a lot of data from our very big experiment (a.k.a. Cage Experiment 1.0), I can confidently say that the fear of being eaten does some crazy things to oyster reefs. And even though most of the ingredients were the same, those crazy things differed from NC to Florida. While our final recipe isn’t perfect, we now have a better understanding of oyster reefs and that the recipe definitely has many more ingredients.

For instance,

  1. Mud crab hearing testThe fear of being eaten has a sound component to it. Previously, we thought fear was transmitted only chemically, but now we know that crabs can hear. This is huge!
  2. Oyster filtration and oyster pooping can affect the amount of excess nutrients in our coastal environment. Our collaborator (M. Piehler, UNC-CH) showed that in some places, this can remove excess nutrients and that this services makes an acre of oyster reef worth 3,000 every year in terms of how much it would cost a waste water treatment facility to do the same job.
  3. In a few months, I hope to update you on how sharks, catfish, drum, and blue crabs fit into the recipe.

In addition to uncovering some new ingredients, our pursuit of this basic science matters because it allowed us to figure out what methods and experiments work as well as what things don’t  (Watch how they reinvented one of their most depended upon tools: The spat tile experiment). In short, the fruits of this basic science project can now be shunted into applied science and the development of interventions to improve the Apalachicola Bay oyster fishery.

But given that the lack of oyster shell in the bay is clearly the problem and that re-shelling the bay would bring the oysters back, why do we need to conduct the research? Well, then again it could be the lack of fresh water coming down the Apalachicola River and/or the lack of nutrients that come with that fresh water. Oh, don’t forget about the conchs that are eating away at oyster reefs in St. Augustine, Florida and may be doing the same to those in Apalachicola.

Shawn Hartsfield tonging for oysters to be used in the Apalachicola Bay experimentLike the chicken piccata recipe, Apalachicola Bay is awesome, but it’s complicated. Clearly, there are lots of things that could be in play. But if we don’t understand how they are all linked, then we may waste a lot of effort because fixing the most important part with Ingredient A may not work without simultaneously fixing another part with Ingredient B. Even worse, maybe Ingredient B must come first!  Only through detailed monitoring and experiments will we figure out how all of the ingredients fit together.

Luckily, my brother shared the fruits of his basic culinary experiments so that I could quickly solve my applied problem: cooking a good dinner for the second date. Similarly, it’s great that we received funding from NSF to conduct our biogeographic oyster study, because now we can quickly apply the same methods and personnel to help figure out what’s ailing the Apalachicola Bay oyster fishery. Basic and Applied science, Yin and Yang.

–David

What’s next?

David’s colleague, Dr. Randall Hughes, takes us through another ecosystem that has been affected by drought in recent years, the coastal salt marsh.  As severe droughts become a normal occurrence, coastal ecosystems like marshes or the oyster reefs of Apalachicola Bay stand to take a beating.  Randall is looking at what makes a marsh stronger in the face of drought and other disturbances.

In the Grass, On the Reef is funded by a grant from the National Science Foundation.

RiverTrekkers climb into Means Creek, named for biologist Bruce Means.

Video: RiverTrek 2012 Days 1 & 2

Rob Diaz de Villegas WFSU-TV

Part 2 of our RiverTrek adventure is now live. You can watch it here.

RiverTrekkers climb into Means Creek, named for biologist Bruce Means.

IGOR chip- filtration 150The web version of the video, which you see above, has some shots of our impromptu spelunking expedition by Means Creek that were not in the air version.  I was waiting on permission to show our cave adventure, which was in a part of Torreya State Park that we were told will be opened to the public at some point in the future.  I got that permission after last week’s Dimensions had been completed.  You may notice that, for a video about a kayak trip, we spend a lot of time in caves, bushwhacking in the woods, or climbing up bluffs.  None of our off-river excursions were in lands open to the public, but were instead near parklands that were (Means Creek in Torreya and Alum Bluff on The Nature Conservancy’s Apalachicola Bluffs and Ravines Preserve, near the Garden of Eden Trail).  With those parks in the northern stretch of the river and the Apalachicola Wildlife and Environmental Area in the south, there are ample opportunities to explore the areas adjacent to the river.  Those protected lands are valuable for their ecotourism potential, but they have a indirect value when it comes to the water in the river, in Apalachicola Bay, and into the Gulf of Mexico.

It has to do with clean (or cleaner, anyway) water.  I wrote last week about the Army Corps of Engineers visit to Apalachicola Bay, and the meeting during which various presenters made their case for the why the river needed more water than has been flowing through the Woodruff Dam.  One presentation that left an impression was that of Dr. Felicia Coleman, Director of the FSU Coastal and Marine Lab.  She was showing how the water flowing from the Apalachicola River had positive effects beyond the bay, and she made an interesting contrast.  She was comparing the “green river” plumes from both the Apalachicola and Mississippi Rivers, the two largest North American sources of freshwater in the Gulf.  Along with the fresh water, they contribute chlorophyll and other nutrients.  There is a striking difference in what each river is putting into the Gulf.

“The two sources are quite different, because one is man made, agricultural… excess nutrients are falling into the Gulf” Dr. Coleman said, referring to the Mississippi, “and the other is a natural nutrient base that’s coming into the bay,” referring to the Apalachicola.  The Mississippi River drains 41% of the continental United States, along with considerable nitrogen and phosphorus such as are found in concentrated fertilizers typically used to grow crops and and keep lawns green.  The areas at the mouth of the Mississippi have been heavily developed, so there aren’t the kinds of coastal ecosystems that would filter these nutrients (though as David Kimbro pointed out to me, the sheer volume of runoff from the Mississippi is greater than what these coastal ecosystems could filter).  All of that nitrogen and phosphorous was of course meant to make plants grow, and a farmer can control how fertilizer is applied to get crops to grow how they want and to maximize their yield.  When it runs off of farms and lawns and into the water, you can’t control what plants grow and how fast.  If phytoplankton gets a super dose of nitrogen, its growth can become unchecked and it can suck the oxygen out of water.  Dr. Coleman estimated that the dead zone off of the Mississippi is about the size of New Jersey.

Shrimp boats in Apalachicola, at the very end of RiverTrek 2012.

So, that’s me taking a hike on Alum Bluff and trying to make it about the oysters in the bay.  But there is a connection to the bay, and as Felicia Coleman illustrated, beyond the bay and into the Gulf.  Gag and red grouper are commercially important fish that are caught in waters that are about 60 feet deep.  They spawn when the green river plume is at its seasonal peak (the flow of the river is not constant).  Dr. Coleman presented a map that showed the greatest concentration of grouper spawning happened within that plume.    So the water flow, which is at an all time low (since people have started measuring it), is crucial to that fishery as well as to the shrimp, crab, and oyster fisheries of the bay.  “If you look at rivers around the world that have had intense fresh water withdrawals,” Dr. Coleman said, “There have been some of the most spectacular fishery failures that we know about, in a global sense.”

Riverlinks

I’m not the only one publishing blog posts on RiverTrek 2012.  My fellow paddler (and author) Doug Alderson wrote this post for his Visit Tallahassee blog.

The Army Corps of Engineers is updating the Apalachicola/ Chattahoochee/ Flint Master Water Control Manual, and they are taking public input.  You can let your voice be heard here.

Stay tuned for Part II of the RiverTrek Adventure on Wednesday November 14 at 7:30 PM/ ET as we complete our journey to the bay.

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Backyard Ecology (Plus new video on Bay Mouth Bar)

Episode 7: Where Everything is Hungry

It’s always a good shoot day at Bay Mouth Bar as every animal seems to be eating every other animal.  Oyster reefs, salt marshes, and seagrass beds- the habitats we’ve covered over the last three weeks- reward those who take the time to look closely.  At Bay Mouth Bar, everything is all out in the open.  For a limited time, anyway…
Dr. David Kimbro FSU Coastal & Marine Lab

IGOR chip_ predators_NCE 150IGOR chip- filtration 150Like most kids, I spent a lot of my formative years in the backyard practicing how to throw the game-winning touch down pass, to shoot the game winning three-pointer, and to sink the formidably long putt.  Although my backyard facilities obviously didn’t propel me into the NFL, NBA, or PGA, they never closed, required no admission fee from my pockets (thanks Mom and Dad!), and were only a few steps away.

Now that I’m striving to be an ecologist at Florida State University, I’m feeling pretty darn lucky about my backyard again. Instead of spending tons of time flying, boating, and driving to far away exotic places, I can use a kayak and ten minutes of David-power to access some amazing habitats right here along the Forgotten Coast.

Part of this coastal backyard was first intellectually groomed by one of the more famous and pioneering scientists of modern-day ecology, Dr. Robert Paine. Five decades ago, Dr. Paine noticed that the tip of Alligator Point sticks out of the water for a few hours at low tide. Of course, this only happens when the tides get really low, which happens about 5 days every month. But when the tip of Alligator Point (which is locally called Bay Mouth Bar) did emerge from the sea each month, Dr. Paine saw tons of large carnivorous snails slithering around a mixture of mud and seagrass. When I first saw this place, my eyeballs bulged out at the site of snails as large as footballs!

Fast- forward 2 decades later: Dr. Paine is developing one of the most powerful ecological concepts (keystone species), one that continues to influence our science and conservation efforts to this very day. Using the rocky shoreline of the Pacific North West as his coastal backyard, he is showing how a few sea stars dramatically dictate what a rocky shoreline looks like.

By eating lots of mussels that outcompete wimpy algae and anemones for space, the sea star allows a lot of different species to stick around. In other words, the sea star maintains species diversity of this community by preventing the mussel bullies from taking over the schoolyard. That’s one simple, but powerful concept….one species can be the keystone for maintaining a system. Lose that species, and you lose the system.

Lightning Whelk

A large lightning whelk found on Bay Mouth Bar in December of 2010.

Ok, let’s grab our ecological concept and travel back in time to Dr. Paine’s earlier research at Bay Mouth Bar. Wow, the precursor to the keystone species concept may be slithering around our backyard of Bay Mouth Bar in the form of the majestic horse conch! In this earlier work, the arrival of this big boy at the bar was followed by the disappearance of all of the former big boys (like this lightning whelk). By eating lots of these potential bullies, the horse conch may be the key for keeping this system so diverse in terms of other wimpy snails.

But why should anyone other than an ecologist care about the keystone species concept and its ability to link Bay Mouth Bar with rocky shorelines of the Pacific NW? Well, what if the lightning whelks eat a lot more clams than do other snails, and less clams buried beneath sediments means less of the sediment modification that can really promote seagrass (Read more about the symbiotic relationship between bivalves and seagrasses here)?  Thanks to Randall’s previous seagrass post, we can envision that less horse conchs could lead to less clams, less seagrass, and then finally a lot less of things that are pleasing to the eye (e.g., birding), to the fishing rod (e.g., red drum), to the stomach (e.g., blue crabs), and ultimately to our economy.

For the past two years, I’ve really enjoyed retracing Dr. Paine’s footsteps at Bay Mouth Bar. But lately, I’m feeling a little more urgent about needing to better understand this system because it’s disappearing (aerial images provided by USGS’s online database at http://earthexplorer.usgs.gov/).

To figure this out, we repeat a lot of what Dr. Paine did five decades ago. At the same time, we are testing some new ideas about how this system operates. For example, if the horse conch is the keystone species, is it dictating what Bay Mouth Bar looks like by eating stuff or by scaring the bully snails? How exactly does or doesn’t the answer affect clams, seagrasses, birds and fishes?

Luckily, because this system is so close, with some persistence and some good help, we’ll soon have good answers to those questions.

Cheers,

David

Ps: Many thanks to Mary Balthrop for helping us access this awesome study system every month.

In the Grass, On the Reef is funded by a grant from the National Science Foundation.

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Four Ways (and more) That Salt Marshes Earn Their Keep

Episode 5: The True Value of a Salt Marsh

Dr. Randall Hughes FSU Coastal & Marine Lab

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Much like David finds it hard to distill why the oysters that he studies are so intriguing, I often struggle to convey the charisma of the salt marshes and seagrass beds where I spend so much of my time. At least people like to eat oysters! It can be harder for people to find a connection with the plants that form so many of the critical habitats along our coast (unless of course people misunderstand the meaning of “In the Grass” and think I study a VERY different type of plant!). But even if it is not recognized, there is a connection between the salt marsh and our everyday lives. Like oyster reefs, salt marshes provide many benefits to society, particularly along the coast:

1. A place to live (for marine and terrestrial animals)

Periwinkle snails are among the many animals that make use of the salt marsh habitat.

Even if you’re one of those folks who find it hard to get excited about a bunch of plants, don’t tune out – the salt marsh is teeming with animals! Snails, fiddler crabs, mussels, grasshoppers, dragonflies, and snakes (!) are all critters that we encounter regularly when the tide is out. And there’s always a bit of an adrenaline rush when you see an alligator hauled out nearby. Even better, when the tide comes in, there are lots of animals that you and I (or at least, I) like to eat. Think blue crabs, mullet, and sea trout, for starters. Studies in Florida estimate that marshes provide up to nearly $7000 per acre for recreational fishing alone. Not bad.

2. A safer place to live (for people)

Although it’s generally frowned upon to build houses in the marsh (since it makes it hard for all those animals I just mentioned to live there), it’s a great idea to have lots of healthy marshes near your coastal property. Marshes can protect the coastline from waves and storms, leading to less damage in areas with marshes present. One estimate places the dollar value of coastal protection in the U.S. at over $8000 per hectare per year in reduced hurricane damages! Although here’s hoping that we don’t get an opportunity to test that particular benefit this year.

In addition to reducing the size and strength of waves, marshes also prevent coastal erosion. An unfortunate example of the role of marshes in erosion control came following the Deepwater Horizon oil spill – plants in areas of the marsh that were heavily oiled died, leading to greatly increased rates of erosion in those areas (Silliman et al. 2012). Although the benefit of marshes for reducing erosion and combating sea level rise has been recognized for a long time, there are not any good estimates for what this erosion control is worth in $$. Given expectations of sea level rise in the coming years, I think that the motivation to understand the conditions that lead to sediment accumulation in marshes will only get stronger.

3. Clean water (for animals and people)

Because marshes lie at the intersection of the land and the sea, they serve as a filter for things trying to move between the two. When it comes to run-off and pollution from the land, it’s a very good thing that they do. Simply having a marsh present can serve as an effective alternative to traditional waste treatment. Of course, the protection can go the other direction too – marshes played a critical role in keeping oil from the Deepwater Horizon oil spill from getting to higher elevations.

4. A place to graze (for livestock)

Support for livestock grazing is an important role of marshes in some areas, including the U.K. Although it’s not a benefit commonly associated with marshes in this area, the decaying fence posts that extend out into some areas of St. Joe Bay suggest that it wasn’t too long ago that marshes were used for a similar purpose here!

I could go on, but these and other benefits of marshes are described in greater detail in a recent review by Barbier and colleagues (which I referenced on this blog in May of 2011). Here is the table that they put together summarizing the monetary benefits that we derive from intact salt marshes:

Luckily for us, salt marshes keep working their magic even in the absence of accolades or appreciation. But greater appreciation is needed to help curb the decline of salt marshes around the world – estimated to be as much as 2% per year! We hope that this blog will help generate greater understanding and enthusiasm for the incredible coastal habitats that we are lucky enough to work in every day. Let us know how we’re doing!

In the next two weeks, we delve into a habitat that we have only occasionally covered: seagrass beds.  Next week we examine, with visiting researcher Dr. Peter MacReadie, seagrass beds’ role in fighting global climate change.  The week after that, we head to Bay Mouth Bar, one of the most ecologically unique places in the world.  Also, we’ll be look at the failure of the Apachicola Bay oyster reefs from a biological perspective.  Here are a few images of our visit to a Saint Joseph Bay seagrass bed and of Bay Mouth Bar at low tide, when you see all kinds of strange and interesting creatures:

In the Grass, On the Reef is funded by a grant from the National Science Foundation.

Music in the piece by Kokenovem and Pitx
DCIM100GOPRO

Oyster reefs. Huh! What are they good for!

Episode 4: The Hidden Value of an Oyster Reef

Weeks ago, we came up with a schedule for posts and videos and somehow had our video on oysters due for the week after Governor Scott declared this year’s oyster harvest a failure.  This led to one minor alteration in the above video, but the video was meant as an overview to the services provided by oyster reefs.  There will be content related specifically to Apalachicola Bay in the coming weeks.

Dr. David Kimbro FSU Coastal & Marine Lab

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There are a lot of things that a marine scientist can study such as charismatic animals (dolphin and turtles) or the waves and currents that fuel my surfing addiction. So, why do I spend most of my time mucking around in mud to study the uncharismatic oyster?

Short answer: because they can provide the foundation for a lot of things that we depend on. Now, some of these benefits or services are obvious and many others aren’t.

Let’s start with the obvious. Just like raising cattle supports tons of jobs and our appetite for hamburgers (I recommend reading Omnivores Dilemma if you want to see how eating meat can be environmentally friendly), the harvesting of oysters financially supports many folks as well as the scrumptious past time of tasting oysters on the half shell as the above video just showed me doing at my local favorite, the Indian Pass Raw Bar!

Unfortunately, the importance of this service was made all to clear to us when the Florida governor recently declared this year’s harvest to be a failure and applied for federal relief for the local economy (Download a PDF of the Department of Agriculture and Consumer Services report here). It’s also unfortunate that this type of bad news has a history of indicating that this natural resource is in trouble and that more trouble may be on the way. To see why, check out a study by Dr. Michael Kirby that showed how this service progressively collapsed from New England down to Florida over the past three centuries. In a nutshell, the pattern of collapse mirrors the increasing number of humans that have over-used this service.

But even if there are no questions about the importance and collapse of the previous service, many folks are asking great questions about whether oysters provide other important services in the form of protected reefs that may offset or exceed their commercial/restaurant value. In other words, what good are oysters to us if they don’t make their way to the raw bar?

A sand flat oyster reef in 2002

An oyster reef built by Dr. Jon Grabowski and Dr. Randall Hughes in 1997, pictured in 2002.

Well, my good buddy Dr. Grabowski’s research used relatively tiny oyster reefs to highlight one less obvious service that involves reefs really ramping up the numbers of commercially and recreationally important fishes (drum) and crabs (stone crabs and blue crabs)….yum!  Given that the oyster reefs used to be 12 feet tall and as long as football fields, can you imagine how many crabs and fishes hung around those really big reefs way back then? Heck, even I could have caught a fish!

Another thing that charismatic and good tasting animals need in order to keep our eyes and tummies happy is some healthy coastal water. Having too much plant-like material (phytoplankton) floating around in the water, sinking to the bottom, and decaying can deplete all of the water’s oxygen. Because such a place is very uninviting for lots of sea life, low oxygen areas will not have many animals that are pleasing to the eye, the fishing rod, or our palette.

Columbia River Water Diatoms

Diatoms, single celled phytoplankton. © Pacific Northwest National Laboratory

Enter the filter-feeding oyster.

While it’s hard to know if today’s tiny amount of oysters reefs sufficiently filter enough water, we do know that the really big reefs of our grandparents and their grandparents time were essentially like huge skimmers in swimming pools as big as the Chesapeake Bay.

As the ESPN football talking heads like to say: C’mon Man! Really?

I kid you not, because Jeremy Jackson and colleagues dug through some Chesapeake mud to figure this out for us. Preserved in the mud is stuff that settled out from the water over time, with deeper mud containing older stuff and shallower mud containing newer stuff. It turns out that as we over-ate and turned the larger oyster reefs into small ones, the stuff in the mud transitioned from sings of healthy water to symptoms of unhealthy water. And because the oyster crashes came before the drop in water quality, it’s more likely that oysters maintained the good water signs as opposed to the reverse scenario of the good water signs maintaining the big oyster reefs.

So this points to a third type of service that oyster reefs CAN provide in the form of water-quality. Admittedly, it’s hard to put a dollar amount on that as opposed to the dollar amount that a dozen raw oysters brings in at a raw bar.

But another less obvious way that oysters can help maintain water quality is by removing the nutrients that a lot of the unwanted phytoplankton depend on.

C’mon Man!

Slide by Ashley R. Smyth, Piehler Lab, UNC Chapel Hill Institute of Marine Sciences.

You see, after oysters suck in the water, filter out their preferred phytoplankton (some are good, but some probably taste as bad as my poor attempt of making southern biscuits), they eventually “poop” their waste out into the mud. Some of this waste makes all sorts of bacteria do all sorts of different things. One of these cool things involves taking a form of nitrogen (think fertilizer on your lawn) that is readily sucked up by nasty phytoplankton and converting it into a form that phytoplankton can’t use (think bad fertilizer that you want to return for a refund).  This is called de-nitrification, and it’s a way that oyster feeding and pooping can help maintain healthy coastal conditions. Even cooler, we can slap a dollar amount on it if we think about how much money it costs a waster-water treatment facility to remove the same amount of nitrogen. My buddy in North Carolina Dr. Mike Piehler did just a study and found that the value of this service is about 2,718.00 dollars per acre of oyster reef. And unlike a dozen raw oysters, this service keeps on giving like the energizer bunny.

Finally, and we are now at service 4 in case you are counting, oyster reefs can buffer the waves and storms that eat away at our shorelines, coastal roads, and homes.

Before signing off, I have to also acknowledge that not every oyster reef performs each of these services. Just like my brother and I look pretty darn similar to someone outside of my family, when you look closer, we are really different. Individual oyster reefs are the same way. Heck, while I can do different things well if you catch me in the morning with a cup of coffee, I often really stink at those same things if you check in with me after a too big and sleep-inducing lunch!

This point segues nicely into my research interest about the “context-dependency” of the obvious and not so obvious services that coastal habitats can provide. In other words, why are some reefs doing some services but others are not? This question really crystallizes the essence of a collaborative project that I’m working on with colleagues from FSU, Northeastern University, University of North Carolina, and University of Georgia.

In our crazy-fun, at times maddening, and democratic research team, we are testing whether the answer depends on differences in big hungry and scary predators like drum and crabs lurking around the reefs. Sure, some of these might eat an oyster that doesn’t make it on to my plate at the raw bar. But overall, they may benefit some reefs by eating a lot of the smaller crabs that really like to munch on oysters. And even if they don’t eat all of these oyster munchers, we’re thinking that their presence may sufficiently freak out oyster munchers so that they spend more time watching their backs and less time munching. Hence, the ecology of fear!

Thanks for wading through this long post. If I promise to write shorter posts in the future, then I hope you’ll follow our journey of testing whether predators help maintain services not only in oyster reefs, but also in the marshes and mudflats of the southeast Atlantic and Gulf coastlines.

Cheers,

David

In the Grass, On the Reef is funded by a grant from the National Science Foundation