Category Archives: In the (Sea) Grass


Crown Conchs, Parenting, and Walks Along the Gulf Coast

We’re pleased to introduce our newest blogger, Jessie Mutz. A graduate student in the Florida State University Department of Biological Science, Jessie will be taking a closer look at some of the many fascinating plants and animals in our area. In the process, she’ll introduce us to FSU students and faculty conducting research across various ecosystems.  She starts in a place familiar to this blog when it comes to FSU research- our very own Forgotten Coast.
Jessie Mutz Graduate Student, FSU Department of Biological Science

With summertime officially and emphatically here in North Florida, many of us are coastward bound. Like long walks on the beach?  As it turns out, you’re not the only one.

Low tide on the Gulf Coast.  Photo by Scott Burgess.

Low tide at the FSU Coastal & Marine Lab, St. Teresa, FL. Photo by Scott Burgess.

Meet Dr. Scott Burgess, a marine evolutionary ecologist and one of the newest faculty in FSU’s Department of Biological Science. Although it’s only the start of his first full summer in Tallahassee, Scott has already been hitting the beach – a prime location for researching the reproductive strategies of intertidal invertebrates like the crown conch, Melongena corona. “This area has a lot of species with an unusual life history type, one that is typically less common in other areas,” he says. “So that’s a big interesting thing: Why are there lots of these weird ones here? Why have all of the species chosen this particular life history in this area of the world?” Continue reading


Interning at the Gulf Specimen Marine Lab: Hands On

Video: Interns at the Gulf Specimen Marine Lab in Panacea, FL, get hands on experience working with marine life and equipment.

Rob Diaz de Villegas WFSU-TV

We’re on a boat, speeding through Apalachee Bay on our way back to land.  We’ve accompanied Cypress Rudloe and two Gulf Specimen Marine Lab interns on a trip to collect samples.  Buckets full of octopus and sea urchins slosh as I take a good look to my left and right and get a firm perspective of where I am.  We’re several miles from the St. Marks Lighthouse; it stands out unmistakably as it was designed to do.  Smoke unfurls over it and into the Gulf, from a controlled burn on the St. Marks National Wildlife Refuge.  I look left and see the mouth of the Ochlockonee River, and follow the contour of the land as it curls out of sight to Alligator Point.  These interns are preparing for a life that keeps them in places like this.  Bravo.

P1080062-smallerOf course, it’s more than merely being outdoors that they’re getting out of the deal.  They’re learning about sea turtle rescue, collecting specimens in the wild, and outreach activities.  This includes leading tours and taking the Seamobile out to where kids who don’t always make it to the coast can touch a horseshoe crab.  The day after our trip, the Seamobile is going to Thomasville, GA for a festival.  The stingray and horse conch that inhabit the tank at the rear of the mobile aquarium will be traveling dozens of miles from their home, but to a place bound to their home nonetheless.  Making that connection is part of the educational outreach that interns perform.

“We take the Seamobile around and do programs on sea turtles, coastal watersheds, marine invertebrates,” Tom Harrah told me as he loaded some critters into one of its tanks.  Tom manages the Seamobile and the intern program at Gulf Specimen.

Just a few miles west of Thomasville is the upper Ochlockonee River.  This makes it a part of Apalachee Bay’s coastal watershed.    If rivers are the strings that connect places like Thomasville to the bay, then standing on this boat I am over a knot.  Two watersheds meet here, the Ochlockonee and St. Marks, rivers whose mouths I can alternately see by turning my head one way or the other.  Somewhat by design, every video I’ve produced over the last few months tugs at this knot, and standing here I trace my way backwards to farms and through underwater caves.

Both Full Earth and Turkey Hill Farms compost using fish waste. The compost should release less nitrogen into waterways.  Both farms are near rivers that drain into Apalachee Bay, so a more efficient means of fertilizing their crops helps keep the watershed cleaner, ultimately benefiting the species that provide fuel to their plants.

Both Full Earth and Turkey Hill Farms compost using fish waste. The compost should release less nitrogen into waterways than synthetic fertilizers. Both farms are near rivers that drain into Apalachee Bay, so a more efficient means of fertilizing their crops helps keep the watershed cleaner, ultimately benefiting the species that provide fuel to their plants.

In our last segment we covered two farms in the Ochlockonee watershed.  Full Earth Farm co-managers Katie Harris and Aaron Suko are cognizant of where their farm is in relation to the river, and it influences the way they work their land.  “We don’t want to negatively impact the local waterways and the groundwater.” Aaron told me. “That’s, I’d say, one of the primary reasons we don’t use synthetic fertilizers.”  In our first segment on the Red Hills Small Farm Alliance, I talked to Louise Divine.  She and her husband, Herman Holley, run Turkey Hill Farm just east of Tallahassee, and near to a small waterway named Black Creek.  Like Full Earth, Turkey Hill is an organic food grower.  And like Aaron and Katie, Louise and Herman are well aware of their place in the watershed.  “I think about it every day.” Louise said.  “I think about it when I drive down the highway and I see Roundup sprayed everywhere.  And I know that that Roundup ends up in Black Creek and I know that Black Creek goes into the St. Marks and I- it makes me insane.”

Excess nitrates from fertilizers figure prominently in stories we’ve done on Wakulla Springs.  It runs off of lawns in Tallahassee and down streets, into sinkhole lakes like Upper Lake Lafayette or into Lake Munson, a heavily polluted waterway that drains into Ames Sink.  Dye trace tests have linked Ames Sink to the springs, its water running through one of the largest underground cave systems in the country.  Nine miles or so after its water emerges from Wakulla Spring, the Wakulla River meets up with the St. Marks.  Wakulla Spring has suffered from an increase an algae due to excess nitrates.  Perhaps due to tidal influence, the lower river’s water appears to be cleaner.

Chloe Jackson is an honors biology student at Florida State University.  She interned at the Gulf Specimen Lab over the summer, and is currently using their dock for an experiment using recruitment tiles (which should look somewhat familiar for those of you who've been following In the Grass, On the Reef over the last few years).

Chloe Jackson is an honors biology student at Florida State University. She interned at the Gulf Specimen Lab over the summer, and is currently using their dock for an experiment using recruitment tiles (which should look somewhat familiar for those of you who followed In the Grass, On the Reef over the last few years).

Both the St. Marks and the Ochlockonee provide an important influx of freshwater to coastal ecosystems.  “There’s a high level of biodiversity in this area” Tom Harrah said.  “There are a lot of rivers coming into the ocean, dumping nutrients.  And there’s just animals everywhere.”*

Tom was new to the area when he volunteered at Gulf Specimen as an FSU biology major.  Eight years later, he’s still here working and enjoying these natural resources.  Intern Cara Borowski’s love of these natural resources manifested itself in a different way, as we cover in the video above.  For her, the thrill is getting kids interested in ecology and fostering a spirit of stewardship.  When she entered the program, she was aiming to be a research biologist.  Now, she’s thinking more about education.  Without an opportunity to host field trips and take the Seamobile to schools, she might never have considered this career path.

 *If you’re confused about the roles of nutrients, which can cause lethal algal blooms but also provide a foundation for all life on earth, I’ll direct you to this blog post written by Dr. David Kimbro about the nitrogen cycle.


Scalloping Saint Joseph Bay Seagrass Beds: Video

Rob Diaz de Villegas WFSU-TV

Double Rainbow

I figured it was a good sign that our first glimpse of Saint Joseph Bay was of it under a double rainbow.  Of course, that required me to ignore all of the rain clouds that caused the rainbows, and some of the far off lightning I saw on our drive to Port Saint Joe.  But why head into my shoot with a negative attitude?  It didn’t take long for the sun to come out after we got on Captain Bobby Guilford’s boat.  I can’t control the weather, but if I could, I’d have arranged it like it turned out.  First, some clouds and precipitation for the rainbow shot, and then the sun we needed to shoot in seagrass beds and, more importantly, to see the scallops we were there to find.  Florida weather is just as often a friend to my shoots as it is a nasty nemesis.

This was a segment I’d been wanting to do since the first summer of the In the Grass, On the Reef project.  I spent a lot of time in Saint Joseph Bay following Dr. Randall Hughes’ salt marsh research, and when scallop season started I would see people head into the bay with buckets, kayaking out with buckets, or zipping by on boats.  Scallops are some of my favorite food.   In the Grass, On the Reef could just as easily have been called Getting to Know the Places Where the Food I Like Lives.  And I did get to know about seagrass beds, and snorkel in Saint Joe Bay looking for shots of horse conchs, sea stars, and even scallops.  What I learned in my time with Randall and her colleague, Dr. David Kimbro, is that seagrass beds are really cool!

Seagrass beds are remarkable ecosystems, and they’re a big part of why I love going back to Saint Joseph Bay as well as other locations on the Forgotten Coast.  Here are some of the cool things I learned about them from my collaborators’ research:

Seagrasses and Blue Carbon

Dr. Macreadie looks through seagrass bedIn 2012, Dr. Peter MacReadie visited Randall in Saint Joseph Bay from the University of Technology in Sydney.  We talked to he and Randall about ecosystem services provided by seagrass beds, and Peter talked to us about the surprising ability of seagrass beds to store carbon from the atmosphere.  As Randall points out in a 2012 post, their storage ability is on par with forests.

Robert Paine/ Keystone Species

Horse Conch on Bay Mouth Bar

Horse Conch (Pleuroploca gigantea)

Our local seagrass beds house a wealth of diversity.  Dr. Robert Paine studied Bay Mouth Bar, just off of Alligator Point, over fifty years ago.  The bar may have the greatest diversity of predatory snails in the world. His observations of the top predator- the horse conch- and the rest of the animals on the bar when the horse conch was present versus when it left in the winter, were influential in Paine’s pioneering of the keystone species concept. The horse conch consumes other snails, keeping their numbers in check so that those snails don’t in turn consume too many clams. The clams benefit the seagrass by filtering water, and so the horse conch is of vital importance to clams and to the habitat. As we know, David Kimbro is very much interested in predators, and so it is natural that he would spend years following up on Paine’s work, even unfunded.

(The one clam that horse conchs eat is the largest you can find in our seagrass beds, the pen shell. That’s what we see Bobby and Adrianne eating in the video above.)

Predator Diversity Loss

True Tulip Snail eating a Banded Tulip Snail

True tulip (Fasciolaria tulipa) eating a banded tulip (Fasciolaria hunteria).

While it’s great that seagrass beds help combat global climate change, provide habitat for scallops and other seafood species, and help filter water, they unfortunately are a habitat on the decline. As seagrass beds shrink, they tend to house a less diverse assemblage of animals. David Kimbro’s graduate student, Tanya Rogers, used a local seagrass habitat to look at the effects of losing diversity. Specifically, the loss of a top predator. David and Tanya have been conducting a follow up to Robert Paine’s Bay Mouth Bar research in the early 1960s. Five decades later, they found that the seagrass beds there are shrinking, and certain snail species have disappeared. This includes the true tulip snail and murex, which are still plentiful in Saint Joseph Bay. The true tulip was a major predator on Bay Mouth Bar. Tanya conducted an experiment to determine how the loss of this predator would affect the clams in the sediment, and how those clams in turn affected the sediment where the seagrass grows. Did the loss of habitat force the tulip off of the bar, or did the loss of tulip (which eats clam consuming snails) help cause the seagrass habitat to shrink?

Ocean Acidification

As global temperatures rise, the ocean is acidifying. This will have increasing ramifications for the plants and animals living in saltwater ecosystems, such as the oysters, clams, and scallops whose shells will weaken. However, recent research shows that seagrass beds might fight that acidification.  Good news for the clams and scallops that live there!

Seagrass bed in St. Joseph Bay, FL

Music in the video by pitx.

Saint Joseph Bay scallop, shucked and ready to eat

Shucking a Saint Joseph Bay Scallop: Video

Wednesday, August 20th, at 7:30 pm ET: WFSU premieres the eighth season of Dimensions.  Tune in to watch our Saint Joseph Bay scalloping EcoAdventure.  We snorkel  seagrass beds, see some fun critters, and breathe underwater with the Snuba.  We also eat some tasty scallops.  But you can’t taste these guys if they’re still in their shells.  Below, Captain Bobby Guilford of Break-A-Way Charters shows us how to shuck our catch.  Captain Bobby took us out on the water in July, and he gave us this quick demo:

Rob Diaz de Villegas WFSU-TV

Another season of EcoAdventures is so close we can almost taste it.  Next week, it’ll taste like bay scallops as we return to Saint Joseph Bay not for science, but to enjoy the products of the seagrass bed ecosystem.  Saint Joe Bay is of course where we’ve been partnering with Dr. Randall Hughes to explore the inner workings of salt marshes and seagrass beds.  Just a bunch of grass?  Not if you like seafood.  Randall will have more about what she’s learned from Saint Joe Bay next week.

P1060980This summer we also spent some time with the WFSU/ FSU Mag Lab SciGirls.  Their annual two week whirlwind through the many aspects of science takes them on a few choice EcoAdventures of their own.  We accompany them to Tall Timbers Research Station as they get to know pine flatwoods ecology in the best way possible- by trapping birds and handling snakes, of course!  Our area is blessed with some of the best examples of longleaf pine forest, an ecosystem that thrives with fire.  We’ll see how various animal species (like those birds and snakes) benefit from burning.

Pied billed grebe at Wakulla SpringsWe also soak the SciGirls in our Water Moves game.  In our last video centering on the game, we followed water from urban Tallahassee to Wakulla Springs, passing through troubled waterways Munson Slough and Lake Munson.  That piece spent most of its time on the game and learning about the Leon County side of the Wakulla Springs watershed.  In our upcoming video, we visit Wakulla Springs itself.  It is an ecological marvel that’s had it’s share of troubles, but can still wow you with impressive sites and an abundance of wildlife.

And there’s more to come.  This year it’s all about connectivity- between lands and waters, between people and the natural spaces around them.  You can see from our new video open that we’ve seen some cool stuff over the last few years.  What would you like to see coming up?

In next week’s video, Captain Bobby also shucks one of these…

Dr. Randall Hughes holds large clam in St. Joe Bay

Keep up with the latest posts, environmental coverage from the WFSU News department and more at @wfsuIGOR.


Predator Diversity Loss and Bay Mouth Bar: The Next Stage

David and Randall’s NSF funded oyster study looks to understand how predators control oyster eating animals such as mud crabs and crown conchs. But this dynamic isn’t exclusive to oyster reefs. They are also investigating how predators might help maintain salt marshes and seagrass beds. In their seagrass bed studies, they have focused on a system loaded with predators: Bay Mouth Bar.
Tanya Rogers FSU Coastal & Marine Lab

Tanya RogersThe very first time I drove from Tallahassee to the FSU Coastal & Marine Lab I saw a black bear crossing the Crawfordville highway. No joke. This was in June of 2010, and I had just driven 5 days and 2800 miles from San Francisco to the Florida panhandle to take up my new job on the Gulf Coast. I had just finished college in Washington state, and I had never before been to the Southeast. What sort of wild place had I ended up in?

IGOR chip_ predators_NCE 150IGOR chip- biodiversity 150A very wild and unique one it turns out, and one I’ve come to know better working for the past few years as a research technician for Dr. David Kimbro in the fascinating coastal habitats of this region. Primarily I’ve been traipsing around oysters reefs across the state for the collaborative biogeographic oyster study (now drawing to a close), but for the past year or so I’ve also been managing our side project in the Bay Mouth Bar system, a sandbar and seagrass bed near the FSU Marine Lab. Bay Mouth Bar is a naturalist’s playground filled with surprises and an astonishing diversity of marine creatures that never ceases to amaze me. It is also a unique study system with an intriguing history out of which we can begin asking many interesting questions. This coming fall I’m excited to be starting as Dr. Kimbro’s Ph.D. student at Northeastern University, and for part of my dissertation I’ve decided to conduct some new experimental research this spring and summer out on Bay Mouth Bar.

Horse conch consuming a banded tulip snail on Bay Mouth Bar.

A horse conch in Tanya’s experiment consuming a banded tulip snail.

Bay Mouth Bar is known for its especially diverse assemblage of large predatory snails, which the ecologist Robert T. Paine conducted a study of in the late 1950’s. In 2010, we began surveying the snail community on the bar, interested in what changes might have occurred in the 50 years since Paine’s time, a period during which very little research had been done in this system. I began synthesizing some of the data we’ve gathered, as well as talking to some of the long-term residents of the area. So what has changed on Bay Mouth Bar since the 1950’s? A number of things in fact:

  • Of the 6 most common predatory snail species, 2 are no longer present: the true tulip and the murex snail.
  • The number of specialist snails (like the murex, which only eats clams) has declined relative to the number of generalist snails (those that eat a variety of prey, like the banded tulip).
  • There has been a drastic reduction in the overall area of the bar and changes in the coverage seagrass, specifically the loss of large meadows turtle grass (Thalassia testudinum).
  • Surface dwelling bivalves (e.g. scallops, cockles), once enormously abundant, are now very rare.
True Tulip and murex Snails (no longer found at Bay Mouth Bar)

The two main snail species no longer found at Bay Mouth Bar, true tulip (The larger snail on the left, eating a banded tulip) and murex (right). The true tulip was, along with the horse conch, a top predator of the ecosystem, while the murex is a specialist snail, eating only clams.

Why is this interesting? Worldwide, we know that species diversity is declining as a result of human activities, that specialists are being increasingly replaced by generalists, and that consumer and predator species often face a disproportionate risk of local extinction. So what are the consequences of realistic losses and changes to biodiversity? Is having a diversity of predators beneficial (e.g. both horse conchs and true tulips) to an ecosystem as a whole? Do some species matter more than others? And how do the effects of predators depend on the type of habitat they’re in, given that habitats (like seagrasses) are also changing in response to the environmental changes? These are some of the questions I’m hoping to address in Bay Mouth Bar system, in which we have documented historical changes in predator diversity.

Tethered community in Tanya's Bay Mouth Bar experiment

One of communities in Tanya’s experiment. At the center are top predators reflecting either the current assemblage (a horse conch alone) or the historic assemblage (the horse conch and true tulip).  The predators are tethered to posts and given enough line to reach the lower level predatory snails (murex, lightning whelks, banded tulips, and Busycon spiratum) on the outside.  Those snails have enough line to get out of the large predator’s reach and forage for food.

This past week, I set up an experiment featuring a menagerie of snails tethered in different assemblages across Bay Mouth Bar. Some assemblages mimic the current assemblage, whereas others mimic the assemblage found on the bar during Paine’s time. These historical assemblages include the snail species no longer found there, which I collected from other locations where they are still abundant. Some assemblages have top predators (e.g. horse conchs) whereas others do not. Some are in turtle grass, others are in shoal grass. We’ll see how, over the course of the summer, these different assemblages affect the prey community (clams, mussels, small snails) and other elements of seagrass ecosystem functioning.

Music in the piece by Donnie Drost.  Theme by Lydell Rawls.

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



Notes From the Field: Leashing Your Clams

Tanya Rogers FSU Coastal & Marine Lab

IGOR chip_ predators_NCE 150It’s a problem commonly faced by field biologists: You want to put some particular critters out in the field in various places, but how do you keep them from getting swept away or wandering off too far, and how do you ever find them again later to see how they did? Behold the tether! So long as tethers are designed not to interfere too much with the animals’ natural behavior (walking around, burrowing, etc), leashing them to a fixed object is generally a good way to relocate them (provided you study something like crabs or snails and not lions or bald eagles). The other fun benefit of tethering marine invertebrates: you can take them for walks (albeit slow ones).

I recently conducted an experiment in which I put tethered baby clams (sunray venus and quahog, about 12 mm long) out on Bay Mouth Bar to see how their growth, survivorship, and burial depth was affected by (1) their location on the bar (NE, SW, SE, NW) and (2) the type of habitat the clams were in (sand, shoal grass, turtle grass). I checked on the clams a month later: some were still alive and growing, others were dead with clues indicating their likely cause of demise – gaping shell with no damage (stress), cracked shell (eaten by crab), drill hole in shell (eaten by predatory snail). My preliminary analysis suggests that survivorship and causes of death varied between habitat types. Next I hope to do a similar sort of study with tethered snails on Bay Mouth Bar.

We want to hear from you! Add your question or comment.

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


Notes From the Field: Horse Conch Honeymoon

Rob Diaz de Villegas WFSU-TV

When we started doing Notes From the Field, the intention was for the researchers and their techs and students to write about interesting things they saw or did while conducting their studies.  But I’m sneaking one in.  A couple of weeks ago I went out to Bay Mouth Bar with David Kimbro and his crew for their monthly sampling of gastropods and bivalves.  Horse conchs were plentiful during the summer months, but as the temperature drops they leave for deeper and warmer waters.  WFSU videographer Dan Peeri and I walked around getting shots of dead turtlegrass, a sign of seasonal change.  Oystercatchers were eating sea urchins; how close would they and the other birds let us get?

It was an interesting but quiet day when we heard a shout at the west end of the bar, facing the open Gulf.  Hanna Garland, newly returned from her graduate study on the crown conch problem south of Saint Augustine, seemed to have found something interesting.  Whenever there’s yelling at Bay Mouth Bar, there’s good footage to be found.  Hanna had found a pair of horse conchs mating.  There were several of the football sized orange snails on this side of the bar, including a second coupled pair.  It seems that they hadn’t quite made it to deeper waters, but were perhaps on the way.  And the behavior we observed got my imagination going.  Do they mate before heading on, laying their eggs in deeper waters?  Is that why they leave in the winter, leaving the door open for increased lightning whelk activity?  We can’t say that based on things we saw one day.  But that is one of the wonderful things about visiting wild habitats: seeing animals behave in different ways and getting glimpses into why things happen the way they do (even if careful study ends up providing an alternate narrative).

Horse conchs make an appearance in my EcoAdventures segment on the Leave No Trace principles on tonight’s episode of Dimensions, at 7:30 PM/ ET.  Part of visiting wild places and witnessing interesting behavior is not influencing it with your own behavior. We go over best practices for not disturbing a habitat and its inhabitants.  And for those who haven’t gotten enough Apalachicola River video, our State Parks One Tank Adventure segment tonight is on Torreya State Park.  Also, you can check out our new Apalachicola River and Bay Basin page, under the EcoAdventures North Florida menu.  From there you’ll have access to all of our videos on the basin (beyond the river and the bay) and play with our interactive photo map.

We want to hear from you! Who has seen any interesting animal behavior based on seasonal change? Add your question or comment.

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


Backyard Ecology (Plus new video on Bay Mouth Bar)

Episode 7: Where Everything is Hungry

(Some species names have changed.)
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

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.



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.

Randall snorkels in a seagrass bed in Saint Joseph Bay Peninsula State Park. Photo by Dr. Peter Macreadie. Peter is a researcher from the University of Technology, Sydney, who is visiting Randall and David.

What Have Seagrasses Done For Me Lately?

Episode 6: Blue Carbon Where the Stingray Meets the Horse Conch

At the beginning of September, Randall and David had a visit from Dr. Peter Macreadie of the University of Technology, Sydney.  In this video, Randall takes Dr. Macreadie for a snorkel in St. Joseph Bay.
Dr. Randall Hughes FSU Coastal & Marine Lab

IGOR chip- habitat 150IGOR chip- filtration 150
We now focus our attention to seagrasses, which as it turns out, often don’t get a lot of attention, at least in comparison to other marine habitats like coral reefs or even salt marshes.

Randall snorkels in a seagrass bed in Saint Joseph Bay Peninsula State Park. Photo by Dr. Peter Macreadie. Peter is a researcher from the University of Technology, Sydney, who is visiting Randall and David.

In part, this lack of attention is due to the fact that seagrasses typically live completely underwater, except at very low tide, and so they are not as noticeable as marshes are. In addition, seagrasses often occur in shallow estuaries not known for their great visibility (and thus not as ideal a location as coral reefs for snorkelers or scuba divers). And, although I disagree, some people just don’t find them very pretty.

Last week as I was starting to think about this post, there was a small uptick in the number of media articles related to seagrasses, at least in Australia. The increased interest was in response to a proposal by the Environment Minister, Tony Burke, to require greater seagrass protection from mining and development projects (read more in this article from the Brisbane Times). As justification for the increased financial burden on companies, Mr. Burke cited the many benefits that seagrasses provide. And just what are those?

Scallop in St. Joseph BaySeagrasses (like salt marshes and oyster reefs) provide habitat for many, many fishes and invertebrates. Studies have found that the number of animals living in seagrasses beds can be an order of magnitude higher than the number living in adjacent coastal habitats. Many of these animals rely on the seagrass beds as a “nursery” that protects them from predators until they grow larger. And lots are recreationally and commercially important species that we like to eat. (Scallops, anyone?)

Seagrasses are also incredibly productive plants, sometimes growing more than 1cm per day, and rivaling our most productive crop species like corn. Because a significant portion of this plant material (particularly the roots and rhizomes below ground) stays in place once the plants die, seagrasses can also serve as important ‘carbon sinks’, or buried reservoirs of carbon. In fact, a recent study estimates that the carbon stored in the sediments of seagrass beds is on par with that stored in the sediments of forests on land!

Although lots of the productivity of seagrass beds makes its way underground, some of it does get eaten. Major consumers of seagrasses include urchins and fishes, as well as the more charismatic dugongs, manatees, and sea turtles.

Spider Crab in St. Joe BaySeagrasses (like salt marshes) also play an important role in reducing nutrients that run off from land into the water. Unfortunately, these nutrients can also lead to the loss of seagrasses, by promoting increased growth of algal “epiphytes” that grow on the blades of the seagrasses themselves. When there are not enough small fishes and invertebrates around to eat these algae, they can overgrow and outcompete the seagrass, leading to its decline. And when the seagrasses become less abundant, the animals that rely on them are also often in danger.

The Big Bend and Panhandle of Florida are home to expansive seagrass beds that also often go unnoticed. But they contribute to the productivity, diversity, and beauty of this area in many ways, as anyone who has been scalloping recently has surely realized!

Here is a quick guide to the animals featured in the video above:
0:40 Horse conch and sea urchin joined suddenly by a stingray
1:41 Juvenile pinfish
1:18 Two shots of a bay scallop
1:33 Sea urchin
1:49 Pen shell clam covered in sea stars (2 shots)
1:56 Horse conch

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


Shells, Buried History, and the Apalachee Coastal Connection

Rob Diaz de Villegas WFSU-TV

IGOR chip- human appreciation 150IGOR chip- habitat 150Have you ever found oyster shells in the dirt of your backyard?  If you have and you live in Tallahassee’s Myers Park neighborhood, then you might be looking at the remains of a powerful native village that rose to prominence over 500 years ago.

Missions San Luis scallop-oysterI was on a shoot for the first episode of our newest program, Florida Footprints. We were at the Florida Museum of History interviewing KC Smith about her involvement in the excavation of the Hernando de Soto winter encampment in 1987.  Back then the city was abuzz about the artifacts being found so widely dispersed off of the appropriately  named Apalachee Parkway.  They had likely discovered the central Apalachee village of Anhaica, where de Soto spent the first winter of his North American expedition.  People were finding piles of artifacts in their backyards.  After the interview, I asked Smith how deep I’d have to dig to see if I had artifacts in my yard.

“Do you have oyster shells in your yard?”  she asked.

Oyster shells?  Evidently, these were the indicator of an Apalachee site.  No one is sure what the shells were used for, though she believes they were used as small dishes.  This is consistent with the interpretation in the photo above, taken at Mission San Luis, of scallop shells storing food stuffs.  As Dr. Bonnie McEwan, Director of Archeology at the Mission, points out, “… Apalachees undoubtedly harvested and ate a lot of oysters when they were near the coast.  But because there was no way to preserve them, they didn’t carry them.”  So they weren’t eating oysters in Anhaica, so far from the coast, they were just bringing the shells back.  Of all the shells they carried with them from Apalachee Bay, the most valuable belonged to a resident of the oyster reef, and to all of the intertidal habitats we follow: The lightning whelk (Busycon contrarium).

whelk-black drink vesselMuch like our coastal shellfish are economically important today, lightning whelk shells were of particular value for the Apalachee.  This had less to do with their meat than it did the size and shape of their shell.  Whelks are predatory snails that get quite large, with an elegant sinistral (left hand) curve.  I imagine that it’s the impressive appearance of a mature Busycon that led to their use in ritual life.  “The outer shells with the columellae removed were used as dippers or cups,” Dr. McEwan said, “and these were used in Black Drink ceremonies. As we discussed, Black Drink was an emetic tea brewed from yaupon holly (Ilex vomitoria) leaves.”  Anyone familiar with the effects of holly knows where the vomitoria species name comes from.  The regurgitation caused by the Black Drink was a form of ritual purification, and was a central component of the ceremonies held in preparation for the fierce and occasionally deadly Apalachee ball game (the ball game is the focus of my segment in Florida Footprints).  In the second photo to the right, you can see an interpretation of what a decorated Black Drink vessel looked like.

And whelks had value far outside of our area.  The Apalachee were part of the Mississippian culture, and with it part of a trade network that stretched to the Great Lakes.  Whelks with chemical signatures identifying them as from the Gulf have been found in Arkansas and Illinois.  “In exchange for the shells,” Dr. McEwan said, “the Apalachees received artifacts made from ‘exotic’ or non-local materials such as copper, lead, mica, and steatite, all of which were found associated with burials at the Apalachees’ Mississippian capital– Lake Jackson.”  Lake Jackson was capital of the Apalachee until about 1500.  Judging by the materials for which they were traded, whelks were highly valued.  Dr. McEwan elaborates on this. “In general, most of these items are found in association with burials of high status individuals throughout the Mississippian world since they conferred prestige.”

Here is a video of a lightning whelk roaming nearby St. Joseph Bay:

Since we’ve started the In the Grass, On the Reef project, one of the things that has interested me most is how the many cultures of this area, spanning thousands of years, have connected with the Gulf.  I’ve enjoyed the illumination I’ve received on this little sidebar to the segment I produced.  The next few episodes of Florida Footprints will move forward in time to cover our history since the Spanish arrived.  Hopefully, we will later also look in the other direction at the people who left oyster middens on St. Vincent Island or to the Aucilla River, where the remains of the first Floridians and the mastodons they hunted continue to be found.

My co-producers on this episode are Mike Plummer and Suzanne Smith.  Suzanne is covering the de Soto excavation and the discovery of Anhaica.  Mike is looking at the Spanish mission period in our area.

Watch a preview of Florida Footprints: Once Upon Anhaica: