Barrier Island Wonderland

Barrier Island Wonderland

Along the northern Gulf coast is a string of long-thin sand bar islands we call barrier islands.  They are called this because they serve as a barrier to the mainland from open water storms.  These long sandy islands are very dynamic and constantly shift and move with the tides, currents, and waves.  They can shift as far as 300 feet after a strong hurricane.

The white quartz sand beaches of the barrier island in the northern Gulf of Mexico.
Photo: Molly O’Connor

Life on these islands can be very tough.  In addition to the constantly moving sand, there is salt spray in the wind, intense sunlight much of the year, high winds at times, and little rainfall to provide freshwater.  Even though our area can receive as much as 60 inches of rain a year, much of this falls in the northern end of the counties, and not on the beaches.  That said, there are freshwater ponds on some the islands and even larger dune lakes in Walton County – there life is not as hard.

 

As you cross a barrier island from the Gulf to the bay, you will cross distinct environmental zones.  These zones are defined by the abiotic factors wind and salt spray and are named by their dominant plant forms having distinct animal life associated with them.

The beach zone seems life-less but it is not. Look beneath the sand.
Photo: Molly O’Connor

The beach is barren.  This is the section of sand that extends from the water line of the Gulf to the first line of dunes.  Few, if any plants can grow here.  The high wave energy will not allow plants to grow along the shoreline, nor in the water itself.  The wind and salt spray are high and the sand ever changing.  All of the animal life here lives beneath the sand.  They emerge when the wind and waves have slowed and scavenge on what they can find for food.  Their primary production comes from the decomposition of the strands of seagrass and seaweed that line the shore – what we call wrack.  Many will filter phytoplankton from the water as the waves wash in and seabirds are constant predators.  When conditions get a little too much, they migrate a little offshore in deeper water to wait it out.  But here fish and larger invertebrates become predators – so, they may not stay long.

The primary dune is dominated by salt tolerant grasses like this sea oat.

Inland of the beach is the first dune line – the primary dune.  This dune field is dominated by grasses because woody plants cannot tolerate the high wind.  Most of these herbaceous plants have fibrous root systems that trap blowing sand and form dunes.  The dominant grasses found here would include panic grass, beach elder, and the sea oat.  The seeds of these plants provide food for creatures like the beach mice and some birds.  Ghost crab burrows are often found here seeking shelter from the high energy environment of the beach.  And, as you would expect, predators visit.  Snakes, coyotes, and fox seeking the small mice.

 

Small round shrubs and brown grasses within the swales are characteristic of the secondary dune field.
Photo: Rick O’Connor

This primary dune line blocks some of the wind and salt spray from the Gulf and allows small woody shrubs to grow.  These shrubs will form a secondary dune system, which may grow slightly higher than the primary dunes.  Shrubs like seaside rosemary, goldenrod, and false rosemary can be found here and give the dunes color when they are in bloom.  The grasses found in the primary dune can also be found here.  Beach mice and ghost crabs can work their way to this environment but because the wind is blocked by the primary dune other animals can be found here including: armadillos, opossum, a variety of snakes, and maybe even a gopher tortoise.  Within the secondary dune field there are low areas that, at times, fill with rainwater.  These are called swales and have their own unique wildlife.  Grasses like broomsedge, needlerush, and bull rush can be found here.  Along the edge you may find carnivorous plants such as the sundew.  Freshwater attracts all wildlife, but the tenants could include a variety of amphibians, reptiles, and even some hardy species of fish.

The top of a pine tree within a tertiary dune.
Photo: Molly O’Connor

On the back side of the island are some of the largest dunes.  These are held in place by salt tolerant trees such as live oak, pine, and even magnolia.  However, these trees look different than the ones that grow in our yards.  They are the same species, but their growth seems stunted and often they look like the wind has blown their growth northward.  This is known as wind sculpting and all of it is caused by the salt spray coming from the Gulf.  These trees form a maritime forest where a variety of wildlife species do well.  Deer, armadillo, opossum, skunks, coyote, fox, raccoon, hawks, owls, eagles, all sorts of snakes and woodland birds can be found here.  In these xeric conditions, it is not uncommon to find a lot of cactus.  Most of these creatures are hiding during the day, but at sunset they begin to move.

 

During these colder winter months, we encourage you to explore these beach habitats.

What is the La Nina? did it impact this hurricane season?

What is the La Nina? did it impact this hurricane season?

I think we can all agree it has been one crazy hurricane season.  We have gone through the entire alphabet, and much of the Greek alphabet, naming storms – a record 30.  Here in Pensacola we had Sally, but we had to prepare for many others that were wobbling around out there.  It seemed this year the computer models were struggling predicting landfall locations.  The “spaghetti” paths of the recent Eta were all over the Gulf.   So, what is going on?  It probably has to do with a warmer Gulf but there has to be more to it than that.  Some have mentioned that it has been a La Nina year, and that the Gulf is more active during such years.  Fair enough… what is the La Nina?

 

It is the opposite of the El Nino – a term more people have heard of.  Okay… what is the El Nino?

The red indicates warm water temperatures. Notice the warm temps in the eastern Pacific – not normal.
Graphic: NOAA

 

 

The El Nino is a warming trend observed in the eastern Pacific Ocean every 2-7 years around Christmas time.  El Nino… “the child”.  There are records of this event going back over a century.  It was first noticed by Peruvian fishermen, who fish some of the most productive waters on the planet.  These productive waters are fueled by the cold Humboldt Current and an upwelling bringing nutrient rich cold waters from the seafloor.  When the El Nino occurs the Humboldt Current warms and “caps” the upwelling from reaching the surface where the food chain can benefit.  The fish move away, and the fishermen notice it.  When people began to colonize southern California, and began fishing for tuna and sardines, they noticed the same thing.  The El Nino moved north of the equator just as it moves south of it. 

 

To better understand this, we will need to know a little about the ocean currents. 

The world rotates on its axis every 24 hours – there, we are off to a good start. 

The sun’s rays hit the earth more directly in the equatorial part of the planet, making it warmer there. 

The cold polar water is more dense and sinks.  The warmer equatorial waters move across the surface of the ocean to fill the void left by the sinking polar water.  But it does not move in a straight line to that point.  The world is turning remember, and this cause the moving water to bend in a curved pattern.  The equatorial water moves west by northwest, warming more as it moves.  This is the equatorial current.  When it reaches Indonesia it is a balmy 80F+ (or so).  This is the land of palm trees and coral reefs – “Bali-Hai”. 

The equatorial currents of the Pacific.
Image: NOAA

The water now moves north towards Japan and Korea before heading towards Alaska.  Here it is called the Kuroshio Current and here it slowly begins to lose its warmth.  As it slides beneath Alaska heading for Canada it is called the North Pacific Current, and then becomes the California Current as it passes the western United States heading back towards the equator.  Here the water is much cooler (60-70F).  There are no coral reefs, but you do find palm trees in southern California.  This coast is also bathed with an upwelling and supports a rich fishery.  

 

The southern Pacific is the same – but the current names are different.  The equatorial current heads west reaching Indonesia and heads south to Australia where they call it the East Australian Current (the EAC of Finding Nemo fame).  This is the home of the Great Barrier Reef.  The currents circle near Antarctica, become colder, and head north along South America as the Humboldt Current (also known as the Peru Current). 

 

Now imagine this…

Imagine the warm equatorial water near Indonesia begins to slide back towards California and Central America.  Imagine this warm water layer then heads north and south to the coasts of California and Peru.  This warm water caps the upwelling and the fish leave – near Christmas time – the El Nino.  Bad times for the fishing fleet. 

Commercial fishing in the California Current.
Photo: NOAA

The atmosphere responds to these ocean temperature shifts.  Normally, the cooler waters reaching the equator from California and Peru move westward forming the equatorial current.  This cool water helps form east winds that move across westward as well.  Known as the Trade Winds, sailors have used them for centuries to reach “good trading locations”.  They are steady and dependable… unless it is an El Nino year.  During El Nino the warmer ocean slows the strength of these winds.  They actually move eastward across Central America and impact the Gulf of Mexico.  During El Nino years these eastward moving Pacific winds push hurricanes out of the Gulf into the Atlantic.  These are the hurricane seasons when Bermuda is hit frequently. 

 

La Nina is the opposite.  The Pacific waters moving into the equatorial area from California and Peru are colder than normal.  These colder waters move faster and farther across the equatorial waters of the Pacific increasing the Trade Winds moving west… not east.  With these Trade Winds moving in the direction they should, even stronger than normal, hurricanes are “sucked” into the Gulf of Mexico.  La Nina seasons are very busy hurricane seasons for us.  And you guessed it, it is a La Nina year.  La Nina usually follows the El Nino and we can sometimes experience them for two seasons, but 12 months is typical. 

 

The thing is La Nina’s have been occurring for centuries.  We have certainly had hurricane seasons that were busier than normal but not to the extent we saw this year.  You have to look at climate change in general, and other atmospheric conditions that could influence this.  I am sure the meteorologists and climatologists are as interested in what happened (is happening) this year as we are. 

 

Hopefully we will not see another season like this for some time. 

Happy Thanksgiving. 

Meet the Author: In Memory of Shep Eubanks

Meet the Author: In Memory of Shep Eubanks

This bio of our friend Shep Eubanks was prepared by Dr. Pete Vergot; Northwest District Extension Director.

Mr. Shepard “Shep” Eubanks, County Extension Director and Extension Agent IV

Shep Eubanks
Gadsden County Extension Director

In 1982 Shepard “Shep” Eubanks began working for the University of Florida as a student in Animal Science where he completed his bachelor’s degree in Animal Science in 1985 and then completed a master’s degree in Animal Science at the University of Florida in 1988. After graduation he started his first position with the University of Florida IFAS Extension as the Livestock Extension Agent I for Columbia County. During this time, Shep cultivated his knowledge and experience of working with farmers and ranchers and introduced his knowledge and love for natural resources and the outdoors. In 1993 Shep was promoted to Extension Agent II with Permanent Status and began his new position in Holmes County Florida as the County Extension Director and Agricultural and Natural Resources Agent where he continued to develop his skills of consulting with farmers, ranchers, and homeowners and a new audience of local county officials. As the County Extension Director, Shep was instrumental in moving from a small three-room office in the Holmes County courthouse to a recently renovated Agricultural Center and Extension office in Bonifay, Florida. Shep hired and worked with a staff of Extension Agents and support staff.  In 1997, Shep was promoted to Extension Agent III and in 2003 he was promoted to Extension’s highest rank of Extension Agent IV.

 

Having an opportunity in 2015 Shep moved “home” to Gadsden County, with his
wonderful wife Genea and their two grown sons, John and Justin, to become the University of Florida IFAS County Extension Director and Agriculture and Natural Resources Extension Agent for Gadsden County. Shep worked with farmers, ranchers, and large landowners and homeowners, assisting them in all areas of agriculture and natural resources providing educational programming leadership and individual consultations to all Gadsden County residents. As the County Extension Director, Shep provided leadership for other Extension Agents and support staff. Shep worked with the former County Extension Director Dr. Henry Grant, along with the Gadsden County Commissioners and leadership, to continue to secure funding and build a new Gadsden County Agricultural Center and convert the older building into the Inman Livestock Pavilion.

 

Shepard “Shep” Eubanks will always be remembered as a kind and thoughtful person, willing to help and assist everyone that he met. Shep was a mentor to many younger Extension Agents and a friend to all Extension Agents across the Florida Panhandle and the State of Florida.

Fish From the Florida Panhandle – Sharks

Fish From the Florida Panhandle – Sharks

This is not a word that most visitors to the beach want to hear.  However, shark attacks are actually not that common and the risk is very low.  People hear this every year on shark programs, but it does not seem to make them feel any better.  Here is what the International Shark Attack File says (as of 2020)…

          Since the year 1580 there have been 3164 unprovoked shark attacks around the world. 

Let that sink in for a moment… 3000 unprovoked attacks on humans in the last 440 years.

Now consider the number of car accident victims that have occurred in the last month within the United States.  See what they are getting at?  Let’s look at more…

          Of the 3164 reported unprovoked attacks (yes… these data only include what was reported) 1483 were from the United States… 47% of them.  This may be due to the fact we are “water people”.  The other top countries are Australia, South Africa, and Brazil, all “water people” as well. 

          Of the 3164 reports 851 were from Florida (27%).  This is the number of reported shark attacks in our state since the Spanish settled it.  This comes out to 2 each year – though the data shows a sharp increase in attacks starting in the 1970s (most have occurred since then). 

          Of the 3164 reports 25 were from the panhandle region (0.8%) and 7 from the Pensacola Bay area (0.2%). 

Let that sink in for a moment.  Seven reported attacks from the Pensacola Beach area since the time DeLuna landed here in 1559… 7. 

And lets once again consider the number of vehicle accidents that will occur in the bay area today. 

 

These numbers have been posted before.  Yet people are still very worried when the hear sharks are in the Pensacola Beach region.  When attacks occur, they are big news.  The International Shark Attack File does give trends and suggestions on what to do.  But as many say, sharks are the least of your worries when you are planning a day at the beach.

 

Now that we have said all of that, they are truly amazing animals. 

 

They are fish but differ in that their skeletons lack hard calcified bone – they are cartilaginous.  There are 25 species in 9 different families in the Gulf of Mexico.  Many are completely harmless – 13 of the 25 have been reported to have had unprovoked attacks somewhere around the world – the white, tiger, and bull sharks leading the way.  Several rarely come close to shore. 

Sharks lack a swim bladder and thus cannot “float” in the water column the way your aquarium fish do.  Some, like the nurse and angel sharks, rest on the bottom.  Others, like the white and blue sharks, swim constantly to get water flowing over their gills. 

Because of this, they are very streamlined with reduce scales.  They actually have modified teeth for scales – called placoid scales.  Their fins are angular and rigid (as are other open water fish) and some can swim quite fast – makos have been clocked at over 30 mph for short distances.  Many have seen video of large white sharks exploding with a burst of speed on a sea lion and actually leaping out of the water with it. 

Many species do lay eggs, but others keep the eggs within and give live birth after they hatch.  One species, the sand tiger, produce four embryos within the mother.  The first to hatch consumes the other three! 

The teeth of sharks are famous.  Rows of them, some pointed, some are serrated, all are designed to cut and swallow.  The tiger shark has a serrated tooth that is angled like a can opener.  They can use this to “open” sea turtle shells – adding them to their rather large menu.  They “shed” these frequently – placing a new sharp tooth where the dull old one was – and will go through tens of thousands of teeth in a lifetime.    

The sensory system is one of the most amazing in the world.  Tiny gelatinous cells along their sides, called the lateral line, detect pressure waves from great distances.  Splashing, thrashing movements made by fish can be detected a mile away – and get their attention.  As they approach the sound their sense of smell kicks in.  It has been said that a shark can detect one drop of blood in thousands of gallons of water – and it is true.  However, the sharks must be down current of the victim to detect it.  Their eyes are much better than most think.  They have “crystals” within their retina that act as mirrors reflecting light that enters.  Imagine turning on a flashlight in a dark room.  Now imagine doing this if the walls and ceiling were mirrors – you kind of understand how they can actually see pretty well even in the low light.  That said, light does not travel well under water, so they rely on their other senses more.  And as if that were not enough.  They have small gelatinous cells around the head region that can detect small electric fields.  When a shark bites, it must close its eyes and – as the fishermen say – “roll back” out of the head.  At this point the shark is basically blind and cannot see the target it is trying to bite.  However, if you move out of the way, the weak electric fields produced by your muscles in doing so can be detected by these cells and the shark knows where you are. 

Cool – and scary at the same time.  Let’s meet a few of these amazing fish in our area.          

 

https://www.floridamuseum.ufl.edu/shark-attacks/

The nurse shark. Notice the barbels (whiskers) on its head.
Photo: NOAA

Nurse Shark

This is one of the bottom dwelling sharks that appear harmless – and they are – but if provoked, they will bite.  They have less angular fins, or a brownish-bronze color, and really like structure – they are found on our reefs.  They posses a “whisker-like” structure called a barbel.  These are common on other bottom fish, like catfish, and possess chemo-sensory cells to detect prey buried in the sand.  They are not as common here as they are in the Keys, but they have been seen.  They can reach lengths of 14 feet. 

Blacktip sharks are one of the smaller sharks in our area reaching a length of 59 inches. They are known to leap from the water. Photo: Florida Sea Grant

BlacktipSpinner

These are grouped together because (a) they resemble each other, and (b) they are both common here. 

They are both stream-lined in shape and have blacktips on their fins.  Actually, spinner sharks have more fins tipped-black than the blacktip.  The anal fin of the spinner is tipped black, but this is not the case for the blacktip.  The spinner gets its name from the habit of leaping from the water and spinning very fast as it does so.  Both are quite common in the Gulf and the bay.  They reach about eight feet in length and unprovoked attacks are very rare. 

The Scalloped Hammerhead is one of five species of hammerheads in the Gulf. It is commonly found in the bays. Photo: Florida Sea Grant

Hammerheads

This is a creepy group – check out the head.  It is one that many people fear, and unprovoked attacks have occurred.  The reader may not know that there are more than one kind – five species actually.  They have a tall dorsal fin which sometimes extends above the water when swimming near the surface – the classic “shark is coming” look.  Their heads are aerofoil shaped and there are several possible explanations for this.  1) It is more aerodynamic, making it easier for this ram-jetter to swim, using less energy to do so.  2) It is a battery of sensory cells.  By swinging the head back and forth, as they do, it is an advanced radar searching for prey, possibly finding it before other sharks do.  There are stories of hammerheads arriving first.  3) It is also believed they use their electric sense to detect buried prey – the shape making this easier to find and expose them.  It could very well be that all of these could explain the shape. 

This pregnant bull shark has an impressive girth.

Bull Shark

Since the film Jaws the world has turned its attention from solely the white shark – to the bull shark.  As you can imagine, it is hard for a shark attack victim to tell you which species bit them – “I don’t know… it was a big gray thing chomping on my leg!”  or “It was a great white!”  because that is the only one many know.  But studies sine the 1970s suggest that the bull shark is an aggressive species and may be responsible for a lot of attacks.  Particularly in the estuaries and upper estuaries.  Bull sharks are what we call euryhaline – they have tolerance for a wide range of salinities.  This shark has been reported in low salinities of the upper estuaries and even into freshwater rivers.  One report had them over 100 miles from the coast – they are certainly where the people are. 

The extremely long upper lobe of the thresher shark.
Image: NOAA

Thresher Sharks

These are bizarre looking sharks.  Most sharks have what we call a heterocercal tail – different – different meaning the upper lobe of the forked tail is longer than the lower.  But the threshers take this to the extreme – the tail can make up almost half of their body length, which can be 20 feet.  It is believed that use this extremely long tail to herd and stun baitfish – their favorite prey.  They prefer colder waters and records in the Gulf are not common.  Those that exist suggest they live offshore and are rarely encountered near beaches.  There are no unprovoked attacks reported from this shark. 

The massive whale shark.
Photo: Florida Museum of Natural History.

Whale Shark

Amazing… heart stopping… what else can you say.  Encounters with the largest fish on our planet are rare – but when they do happen you will never forget it – it will be one of the highlights of your life.  As the name suggest – these are large sharks, with a mean length of 45 feet but some reporting in at 60 feet.  They are easily recognized first by their size, but also their coloration.  They are brownish color with beige or white spots in nice rows running across the dorsal side.  They swim slowly filtering plankton from the sea – though will occasionally take in a fish.  Some reports show them vertical in the water column moving up and down filtering from a school of plankton or tiny fish.  They are rarely seen because they tend to dive deeper during the day with the plankton layer – then surfacing at night following the same plankton.  They are, unfortunately, sometimes struck by boats while at the surface. 

Fish From Florida’s Panhandle Seagrass Beds

Fish From Florida’s Panhandle Seagrass Beds

Seagrasses have been described as the “nursery of the sea”.  Studies show that up to 90% of the commercially valuable fin and shellfish species spend part, or all, of their lives in these submerged meadows.  As you can imagine, these grasses must grow in clear, relatively shallow waters – so they are more inshore.  You might also imagine that most of the fish living here are going to be small.  There are the larger predators in this grassy world, but most are going to be small enough to hide amongst the blades. 

These inshore seagrass meadows not only provide hiding places but provide food as well.  Interestingly, most do not feed on the grass directly, but rather the tiny plants and animals that are attached to the blades – what are called epiphytes and epizoids.  Those that feed on these are then preyed upon by slightly large creatures until we find the larger apex predators – like the speckled trout. 

Many of those who reside here are specialist in camouflage and mimicry, and others might be ones who actually live in the sand bordering the edge of the meadows – waiting for a chance to pounce on unsuspecting food.  Let’s meet a few of these interesting fish. 

Photo: Nicholls State University

 

Pinfish

You are at the beach for a day of fun and sun.  You enter the water of Santa Rosa Sound to play at the edge of the seagrass bed, or maybe to snorkel and explore it.  As you stand on the sand you feel little nips at your ankles and immediately think – CRAB! But you would be wrong.  As you look closer you will see it came from a small fish – and the more you stir the sand, more of these small fish arrive.  They are probably feeding on the small invertebrates that are stirred up from your movement, but they periodically nip at you as well. 

This small fish is a very common member of the inshore fish community known as the pinfish.  They are members of the Porgy family, related to sheepshead, and have incisor teeth for crushing the shells of their prey.  Most locals are first introduced to them as a kid while fishing.  They seem to bite, or steal, any bait you put on.  Most often used as bait themselves, they are actually edible – but you need one of the large ones to have a meal.  They get their common name from the sharp spines of their dorsal fin.  When snorkeling in the grassbeds you will find they are the most common fish there. 

Photo: USGS

Needlefish

These guys look scarier than they are.  Long skinny fish with long skinny snouts that hold long skinny teeth.  They resemble barracuda and have the look as if they could attack and do some damage – but they are harmless, unless you catch one in a net, then they will swing their long skinny heads towards your hand for snip. 

These small predators travel above the grassbeds looking for potential prey hiding among.  Small juvenile fish seem to be what they want.  Though often just referred to as “needlefish”, there are actually four species, but they are hard to tell apart. 

Photo: NOAA

Seahorses

These are captivating fish, and very hard to find as they blend in so well, but they are there – along with their close cousins the pipefish.  It seems hard to call it a fish at all – it certainly does not look like one.  Swimming vertically in the water, no tail to speak of, they seem like a creature in their own group.  But they are fish.  The scales are fused into an armor plating and they do have both gills and fins – characteristics of fish.  They will use their prehensile tail to grab onto a grass blade, hanging there waiting for tiny shrimp to swim by which they inhale using a vacuum like motion with their tube-shaped mouths. 

Pipefish resemble seahorses but are elongated, with a distinct fin for a tail, and swim horizontally as most fish do.  They will turn vertically in the grass to appear to be a blade themselves and hunt similar prey as their seahorse cousins. 

A well-known characteristic of this group is the fact that the males carry the fertilized eggs – not the females.  Males can be identified by the brood sac on their ventral side and they may carry up to 80 eggs.  The eggs hatch within the pouch and the young are born alive. 

Photo: NOAA

Puffers

This group of fish are famous for their ability to “blow up”, or inflate like a balloon, when threatened.  Kids love to play with them and get a kick out of watching them inflate.  These are round bodied – slow moving fish, which is one reason they inflate.  It does not matter if you can catch them, you cannot swallow them if you do! 

There are actually two different families of “blowfish”.  The true puffers are smaller (3-12 inches), have tubercles on their bodies instead of long spines, and the teeth in the upper and lower jaw have a space forming four teeth (two on the top jaw, two on the bottom) – giving them their family name “tetradontidae”.  The “burrfish” are larger in size (1-2 feet), have long spines on the body, and no median in the teeth – so only one tooth on the top jaw, one on the bottom – “diodontidae”. 

The most common one found is the striped burrfish.  The big boy of the group – the 2-foot porcupine fish – is rare in the northern Gulf and prefers the reefs of the open sea to grassbeds. 

When threatened they will inflate with water (or air) and try to continue swimming.  After the danger has passed, they will deflate and go about their merry way.  There are stories about their flesh being poisonous and dangerous to eat – it is true.  The compound they produce is one of the more toxic found in the fish world.  Though there are certified chefs around the world who can safely clean them, it is not recommended you eat these.