Santa Rosa Portion of the Oyster Mapping and Assessment Project
Santa Rosa County R.E.S.T.O.R.E. has funded the SRC Oyster shell recycling program and the Pensacola, East and Blackwater Bays Intertidal and Subtidal Oyster Reef mapping and Assessment projects. The Nature Conservancy is managing the oyster reef mapping and assessment project and has contracted with MREC Environmental, LLC to get the work done.
The purpose of the project is to map and assess the condition of known and potential intertidal and subtidal oyster reef resources in the Santa Rosa County portion of the Pensacola Bay system. Results of this mapping project will establish a baseline of the existing locations and condition of oyster resources in SRC. This information will help to guide future restoration projects.
Subtidal oysters are harvested in clumps and are culled using a large knife or hatchet. Photo credit: Calvin Sullivan
Intertidal reefs are typically exposed at low tides and found along the shoreline of our bay system. Sub-tidal reefs are found under water. Gabe Johnson, owner of MREC Environmental has verified existing intertidal reefs using a jet-ski in the fall of 2020. Our bay system does not have as many natural intertidal reefs as in other parts of Florida. There are existing intertidal reefs that have been installed for shoreline protection and habitat enhancement.
Gabe Johnson and the crew of MREC Environmental are working to complete the initial bottom survey in early 2021. He has set up grids based on historic locations of oyster reefs throughout the Santa Rosa County portion of the Pensacola Bay system. He will then verify his findings by diving sites where oyster shell was found during the bottom survey.
From left to right: Dale, Gabe and Reese of MREC Environmental. Phot credit: Chris Verlinde
Side scan sonar and echosounder along the side of the boat. Photo Credit: Chris Verlinde
Gabe and his crew are using one Side Scan Sonar, an Edgetech 4125i to map images of the bottom. The other instrument they are using is a Singlebeam Hydrographic Echosounder (Teledyne Odom Echotrac CV100). The echosounder is used to collect water depth data and contours of the water bottom. The echosounder is connected to a transducer. The side scan sonar and the transducer from the ecosounder are placed along the side of the boat and submerged while the boat travels over the transects to collect the underwater images and parameters.
The pink lines are the transect lines of grid #25. Photo credit: Chris Verlinde
About two thirds of grid #25 are completed. Photo credit: Chris Verlinde
Dale dropping the pole to assess bottom characteristics. Photo credit: Chris Verlinde
On a cold day in December 2020, Gabe and his crew covered 149.3 acres in grid #25, just west of the power lines in East Bay. Grid 25 included 32 parallel transect lines (2468 feet long), spaced 100 feet apart. This grid was completed in approximately three and a half hours by running the boat along each transect and recording data. In addition to the electronic data, one of the crew members used a fiberglass pole to assess bottom conditions. Approximately, every 10 feet or so, the pole guy would lower the pole and shout the condition of the bottom, either sand, mud, or shell. Gabe then recorded the point and code on his mapping software.
Image from the side scan sonar showing a sand bottom. Photo credit: Chris Verlinde
Side scan image of bottom with showing potential shell (the darker scatter area). Photo credit: Chris Verlinde
The raw data will be compiled into maps and a report that will be used to based future oyster fishery and habitat enhancement restoration efforts in East, West and parts of Escambia Bay.
Carrie Stevenson is the Coastal Sustainability Agent for the UF/IFAS Escambia County Extension Office, and has been with the organization almost 17 years. Her educational outreach programs focus on living sustainably within a vulnerable coastal ecosystem. She helps clientele better understand how to protect and preserve local ecosystems and water resources, wisely use our abundant rainfall and sunlight, and prepare and mitigate for flooding, coastal storms and climate impacts.
Growing up an avid reader and science junkie, a young Carrie aspired to find a career that allowed her to “be outdoors and wear jeans,” and in college sought to become a science writer. When National Geographic didn’t come calling, she found a position as a field-based environmental specialist with the Florida Department of Environmental Protection. There, she handled compliance and enforcement cases related to stormwater and wetlands, spending days tromping through the swamps, wet prairies, and newly build subdivisions of northwest Florida. After joining UF IFAS Extension, she spent 6 years as a Florida Yards & Neighborhoods Agent before switching to Coastal Sustainability. Her expertise and articles focus on climate issues, stormwater, hurricanes, native plants, and wetlands.
A lifelong outdoors enthusiast, she enjoys biking, standup paddleboarding, and traveling to national parks with her family. She also has many favorite international outdoor experiences, ranging from hiking glaciers in Canada to snorkeling coral reefs in Belize and watching elephants drink from a South African river. A native of Mississippi, Carrie has lived with her husband in Pensacola since 1999. Carrie earned her master’s degree in Biology/Coastal Zone Studies from the University of West Florida in Pensacola and an undergraduate degree in Marine Science from Samford University (Birmingham, Alabama). She is the proud mom of an Eagle Scout and leads her daughter’s Girl Scout troop. She is a Fellow in the Natural Resources Leadership Institute (NRLI), past president of the Florida Association of Natural Resource Extension Professionals (FANREP), and member of IMPACT 100 Pensacola Bay.
Recently there was a report of high fecal bacteria in a portion of Perdido Bay. I received a few concerned emails about the possible source. Follow up sampling from several agencies in both Florida and Alabama confirmed the bacteria was there, the levels were below both federal and state guidelines (so no advisory issued), and a small algal bloom was also found. It was thought the cause was excessive nutrients and lack of rain.
We hear this a lot.
Excessive nutrients and poor water quality.
What is the connection?
Many people understand the connection, others understand some of it, others still do not understand it. UF IFAS has a program called LAKEWATCH where citizen science volunteers monitor nutrients in some of lakes and estuaries within the state. Here in Escambia County, we have six such volunteers. Some of the six bodies of water have been monitored for many years, others are just starting now, but the data we have shows some interesting issues – many have problems with nitrogen. Let’s look closer.
The nitrogen cycle.
Image: University of Florida IFAS
We have all heard of nitrogen. Many will remember from school that it makes up 78% of the air we breathe. In the atmosphere nitrogen is present as a gas (N2). It is very common element found in living creatures – as a matter of fact, we need it. Nitrogen is used to build amnio acids – which builds proteins – which is needed to produce tissue, bone, blood, and more. it is one of the elements found in our DNA and can be used to produce energy. However, it cannot do these in the atmospheric gas form (N2) – it needs to be “converted” or “fixed”.
One method of conversion is the weather. Nitrogen gas are two molecules of nitrogen held together by strong chemical bonds (N2). However, lightning provides enough energy to separate N2 and oxidize it with oxygen in the atmosphere forming nitrogen dioxide (NO2). This NO2 combines with water in the atmosphere to form nitric acid (HNO3). Which can form nitrates (NO3) with the release of the hydrogen and nitrate (NO3) is usable by plants as a fertilizer… a needed nutrient.
But much of the usable nitrates do not come from the atmospheric “fixing” of nitrogen via lightning. It comes from biological “fixing” from microbes. Atmospheric nitrogen can be “fixed” into ammonia (NH3) by bacteria. Another group of bacteria can convert ammonia into nitrite (NO2), and a third group can convert it from nitrite to the usable form we know as nitrate (NO3). Ammonia can also be found in the environment as a waste product of life. As we use nitrogen within bodies it can be converted into ammonia – which can be toxic to us. Our bodies remove this ammonia via urine, and many times we can smell this when we go to the restroom. Nitrogen fixing bacteria can convert this ammonia to nitrites as well and complete the nitrogen cycle.
Once nitrogen has been fixed to the usable nitrate it can be taken up by plants and used within. Animals obtain their needed nitrogen by eating the plants or eating the animals that ate the plants. In both cases, nitrogen is used for protein synthesis in our bodies and unused nitrogen is released into the environment to continue the cycle.
So, what is the connection to water quality?
You might think that excessive nitrogen (nutrients) in the water would be a good thing. Released ammonia, though toxic, could be “fixed” into nitrite and eventually nitrate and recycled back into life. And you would right. Excessive amounts of ammonia though, may not be converted quick enough and a toxic state could occur. We see this in aquaculture ponds and home aquaria a lot.
Members of the herring family are ones who are most often found during a fish kill triggered by hypoxia.
But what about excessive nitrates? Shouldn’t that be good for the plants?
The concept makes sense, but what we see with increase plant growth in aquatic systems is problematic. Excessive plant growth can cause several problems.
1) Too much plant growth at the surface (algae, leafy vegetated material) can block sunlight to the other plants living on the bottom of the waterway. This can cause die off of those plants and a mucky bottom – but there is more.
2) Excessive plant growth at the surface and the middle of the water column can slow water flow. Reduced water flow can negatively impact feeding and reproductive methods for some members of the community, cause stagnation, and decrease dissolved oxygen – but there is more.
3) Plants produce oxygen, which is a good thing, so more plants are better right? Well, they do produce oxygen when the sun is up. When it sets, they begin to respirate just as the animals do. Here excessive plants can remove large amounts of dissolved oxygen (DO) in the water column at night. If the DO levels reach 3.0 µg/L many aquatic organisms begin to stress. We say the water is hypoxic (oxygen starving). When a system becomes hypoxic the animals will (a) come to the surface gasping, (b) some even approach the beach (the famous crab jubilee of Mobile Bay), (c) leave the water body for more open water, (d) die (a fish kill). This is in fact what we call a dead zone. Not always is everything dead, in many cases there is not much alive left – they have moved elsewhere so we say the bottom is “dead”. Here is something else… as the dead fish and (eventually) dead plants settle to the bottom they are decomposed by bacteria. This decomposition process requires dissolved oxygen – you guessed it – the DO drops even further enhancing the problem. In some cases, the DO may drop to 0.0 µg/L. We say the water is now anoxic (NO oxygen). I have only seen this twice. Once in Mobile Bay, and once in Bayou Texar. But I am sure it happens more often. The local environment can enhance (or even cause) this problem as well. Warm water holds less oxygen and much of the oxygen dissolved in water comes from the atmosphere – by way of wave action. So, on hot summer days when the wind is not moving much, and excessive nutrients (nitrogen) is entering the water, you have the perfect storm for a DO problem and possible fish kill.
4) Oh, and there is one other issue… some of the algae that produces these blooms release toxins into the water as a defense. These are known as harmful algal blooms (HABs). Red tide is one of the more famous ones, but blue-green blooms are becoming more familiar. So now you have a possible hypoxic situation with additional toxins in the water that can trigger large fish kills. Some of these HABs situations have killed marine mammals and sea turtles as well.
Though this process can occur naturally (and does) excessive nutrients certainly enhance them, and in some cases, initiate them. So, too much nitrogen in the system can be bad.
So, what does the LAKEWATCH data tell us about the Pensacola Bay system?
Well, first, we have not had volunteers on all bodies of water for the same amount of time. We currently have volunteers monitoring (1) northern Pensacola Bay, (2) Bayou Texar, (3) Bayou Chico, (4) Bayou Grande, (5) Big Lagoon, and (6) lower Perdido Bay. Pensacola Bay has JUST started, and Big Lagoon has not even started yet (COVID-19 issues) – so we only have data from the other four. Bayou Texar has the longest sample period at 13 years.
Lakewatch is a citizen science volunteer supported by the University of Florida IFAS
Second, this program does not sample for just nitrogen, but another key nutrient as well – phosphorus. When you look at a bag of fertilizer you will see a series of numbers looking like: 30-28-14. This would be nitrogen, phosphorus, and potassium. People adding fertilizer to their lawns should know which nutrient they need the most and can by a fertilizer with a numerical concentration that is best for their lawn. You can have your soil tested at the county extension office. But the point here is that there is more than nitrogen to look at and, as we have learned, more than one form of nitrogen out there. So, what we do at LAKEWATCH is monitor for total nitrogen (TN) and total phosphorus (TP).
Another parameter monitored is total chlorophyll a (TC). The idea is… if there are excessive amounts of nutrients in the water there will be excessive amounts of algae. You could collect a sample of water and count the number of algal cells in the water – but another way is to measure the amount of chlorophyll in the water as a proxy for the amount of algae. Chlorophyll, of course, is the compound within plants that allows photosynthesis to happen. There is a chemical process used to release the chlorophyll within the cells and you can then use an instrument to measure the amount of chlorophyll in the water.
LAKEWATCH volunteers also monitor water clarity. It is true that clarity can be impacted by sediments in the water as much as an algal bloom, but anything that contributes to less sunlight reaching the bottom can be problematic for some bodies of water. This is done by lowering a disk into the water and measuring the depth at which it “disappears”.
For those not familiar with the term salinity, it is the measure of the amount of dissolved solids in the water – what most people say, “how salty is it?”. For reference, the Gulf of Mexico is usually around
35‰, most open estuaries are between 20-30‰.
Below is a table of the LAKEWATCH data we have as of the spring 2020.
|Year of Sampling
||Body of Water
||Total Phosphorus (µg/L)
||Total Nitrogen (µg/L)
||Total Chlorophyll (µg/L)
||Water Clarity (feet)
|2014 – 2018
||350 – 600
||10 – 30
||2.6 – 4.2
||7.0 – 8.2
|2012 – 2017
||16 – 19
||320 – 340
||4.0 – 5.2
||17 – 18
|2007 – 2018
||17 – 18
||600 – 800
||6 – 8
||3.4 – 3.8
||8 – 10
|2014 – 2018
||350 – 360
||5.3 – 6.1
There are a couple of things that stand out right away
(keep in mind some water bodies have not been monitored very long by LAKEWATCH).
1) Phosphorus is not as big a problem in our part of the state. In the peninsula part of Florida there is a lot of phosphorus in the sediments and much of it is mined. You can see this in the average value for the state. Actually, because of this, many of the central and south Florida lakes are naturally high in phosphorus and this is not considered “polluted”. All that said, there are higher levels of phosphorus in Bayou Chico. Which is interesting. More on solutions in a moment.
2) We have a lot of nitrogen in our waters. Bayou Texar in particular is much higher than the state average. More on this in a moment.
3) We have a little more chlorophyll than the state average, but not alarming.
4) Bayou Grande and lower Perdido are clearer than Bayou’s Texar and Chico.
5) All these bodies of water are less than 20‰. More on this as well.
1) We already discussed the phosphorus issue (or non-issue), but what about Bayou Chico? Phosphorus is NOT introduced to the system from the atmosphere as nitrogen is – rather, it comes from the sediments. High levels of TP would suggest high levels of sediments in the water column (the water clarity data supports this) – which suggest high levels of run-off. The watershed for Bayou Chico is highly urbanized and run-off has historically been a problem.
2) Nitrogen can come from many sources, but when numbers get high – many will hypothesize they are most likely from lawn run-off (fertilizers), or sewage (septic leakage, sanitary sewage overflows, animal waste). There are certainly other possibilities, but this is where most resource managers and agencies begin.
3) Elevated chlorophyll indicates elevated primary production. This is not unusual for an estuary. They are known for their high productivity. Bayou Chico seems have more algae than the others. Most probably due to the increase levels of nutrients entering the watershed.
4) Bayou Grande and lower Perdido Bay have better water clarity than Bayou’s Chico and Texar. Though all four bodies of water have significant coastal and watershed development, Bayou’s Chico and Texar and completely developed as well as their “feeder creeks”. Again, indication of a run-off problem.
5) All four bodies of water have several sources of freshwater input as well as stormwater run-off that has contributed to the lower salinities found here. It is possible that the salinities here were less than 20‰ prior to heavy development.
There is a common theme with each of these – stormwater run-off. Rain that historically fell on the land and percolated into the ground water, now flows off impervious surfaces (streets, driveways, parking lots, even buildings) into drainage pipes and discharges into the waterways. This stormwater carries with it much more than just fertilizers and animal waste, it carries pesticides, oil, grease, solid waste, leaf litter, and much more.
How do you reduce stormwater?
Well, there is not much you can do with impervious surfaces now, but the community should consider alternative materials and plans for future development – what we call “Green Infrastructure”. Green roofs, pervious streets and parking lots, there are a lot of methods that have been developed to help reduce this problem.
Another consideration is Florida Friendly Landscaping. This is landscaping with native plants that require little (or no) water and fertilizer. It also includes plants that can slow run-off and capture nutrients before they reach the waterways and methods of trapping run-off onto your property.
If you happen to live along a waterway, you might consider landscaping your property by restoring some of the natural vegetation along the shoreline – what we call a living shoreline. Studies have shown that these coastal plants can remove a significant amount of nitrogen from the run-off of your property as well as reduce coastal erosion and enhance fisheries by providing habitat.
Closed due to bacteria.
Photo: Rick O’Connor
What about sewage issues?
Unfortunately, most septic systems were not designed to remove nitrogen – so leaks occur and will continue. The only options you have there are (a) maintain your septic by pumping once every five years, (b) consider taping into a nearby sewage line.
Sewers systems are not without their problems. Sanitary sewage overflows do occur and can increase nitrogen in waterways. These are usually caused by cracks in old lines (which need to be replaced), are because we flush things down drains that eventually “clog the arties” and cause overflows. Things such as “flushable wipes”, which are flushable – they go down the drains – but they do not breakdown as toilet paper does and clog lines. Cooking grease and oil, and even milk have been known to clog systems.
Our LAKEWATCH volunteers will continue to sample three stations in each of their bodies of water. We are looking for a volunteer to monitor Escambia Bay. If interested contact me.
If you are interested learning more about green infrastructure, Florida Friendly Landscaping, or living shorelines lines contact your county extension office (850-475-5230 for Escambia County). If interested in issues concerning sanitary sewage overflows or septic issues, contact your county extension office, or (if in Escambia or Santa Rosa counties) visit ECUAs FOG website (Fats, Oils, and Grease) https://ecua.fl.gov/live-green/fats-oils-grease.
In my time educating the public about Florida turtles I have found that most Floridians have not heard of diamondback terrapins. They have heard of, and seen turtles, but are not sure what the names of the different species are and are not familiar with the term terrapin at all. Which brings up the question – what is the different between a turtle, a tortoise, and a terrapin?
The light colored skin and dark markings are pretty unique to the terrapin.
Photo: Molly O’Connor
Honestly, they are cultural terms and not “biological” descriptions. We associate the term “tortoise” with a land turtle – and this is true – yet we call the box turtle a “turtle” – which is fine. In Great Britain they call almost everything a “terrapin”. The term “terrapin” is a Delaware Indian term meaning “edible turtle”. Most turtles are edible, but this term stuck to a group of brackish water turtles in the Chesapeake area near Delaware we now call “terrapins”.
In the Mid-Atlantic states, terrapins are more known than they are here – and they appear to be more abundant. They are the mascot of the University of Maryland, and the official state reptile there. “Turtle Soup”, a popular cultural dish in the Chesapeake, is made with terrapins. It was served as part of the state dinner when Abraham Lincoln was president – considering it a classic “American” dish. They were harvested by walking through the marshes with a burlap sack and a gig. A sack could bring a harvester about $10, but when the popularity of the dish increased, hand harvesting could not keep up with demand and terrapin farms began. I know there were terrapin farms in the Carolinas, but there was one near Mobile, Alabama as well. Apparently, terrapins existed outside of the Chesapeake – and that brings us back to Florida… we have them too!
Ornate Diamondback Terrapins Depend on Coastal Marshes and Sea Grass Habitats
There are seven subspecies of this brackish water turtle. They range from Massachusetts to Texas. It is the only resident brackish water species, spending its whole life in salt marshes (or mangroves in south Florida). Florida has five of the seven subspecies, and three of the seven ONLY live in Florida – yet most of us do not know the animal exist.
Very few researchers worked with terrapins in this state – there was virtually nothing known about them in panhandle. In 2005 I began to survey panhandle marshes to see if terrapins existed here. I grew up in the panhandle, and like so many others, had never seen or heard of one. I asked local fishermen who use to gillnet the marshes back in the 1950s and 1960s (when it was allowed) if they were aware of this this turtle. I asked them “did you ever capture a terrapin?” They did not know what I was talking about. And then I showed them a picture… “OH… yea, we did catch these once in a while – what are they called again? Terrapins?”. This was a game changer for me in terrapin education – show them a terrapin and ask if they have ever seen a turtle that looks like this.
The response was still “what is that? It’s beautiful!”… and they are. Terrapins have light colored skin with dark specks or bars – a really pretty cool looking turtle. Oh, and they are in the panhandle, just not in big numbers – or, at least, we have not found them in big numbers 😊.
These brackish water turtles spend their entire lives in a marsh system feeding on mollusk and crustaceans. Like map turtles (their nearest cousins), the females are larger with wide heads for crushing the shells of their prey. They are considered an important member of the ecosystem in that the reduction of terrapins can cause an increase in the marsh periwinkle (a popular snail food) who would in turn stop feeding on leaf litter and attack the live plants themselves – threatening the existence of the marsh. So, they are important predators on marsh grazers. Not having a lot of trees in a salt marsh, you do not see them basking on logs as you do with other riverine turtles. They do, however, exit the water and bury in the mud/sand for long periods to bask.
A baby terrapin.
Photo: Molly O’Connor
After mating, the females usually leave the marsh for the open estuary, swim along the shorelines looking for high/dry ground for nesting. More often than not, these are sandy beaches – but they have been known to dig nest in crushed shell mounds, dredge spoil islands, along highways, backyards, and even runways of airports – wherever “high and dry” can be found in a marsh. In Louisiana a lady found one roaming around inside her outdoor shower – good luck nesting there!
The females lay about 10 eggs in a clutch and will lay more than one clutch each year. Baby terrapins are one of the coolest looking turtles you will see. They emerge from the nest in late summer and fall, hiding in the wrack debris along the shoreline. It is believed they actually have a more terrestrial life early on before entering the water and living out their lives in the marsh.
The popularity of turtle soup has waned since the Civil War, as have the wild harvest and aquaculture projects. However, the turtle is still under tremendous pressure from humans. We began using wired crab traps in the 1950s and terrapins have a habit of swimming into these, where they drown. The problem is not that large in Florida, but in the Chesapeake, they have found as many as 40 terrapins in one crab trap! Most of these are “ghost crab traps” – ones that “got away” from the owner but are still harvesting marine live – including crabs. One paper indicated that in the early part of the 21st century, in one year in the Chesapeake, over 900,000 blue crabs died in ghost crab traps – a commercial value of about $300,000. So, the ghost crab trap is a problem whether it kills terrapins, redfish, flounder, or blue crab. Today, many crab traps have biodegradable panels so that if the trap “gets away” it will eventually breakdown and not capture organisms like terrapins. In the Chesapeake many states require crab traps to have a By-Catch Reduction Device (BRD) to keep terrapins out – but allow crabs in. They are not required in Florida, however FWC will provide them for free if you are interested. I have some in my office in Pensacola and more than willing to give them to you. FWC also hosts crab trap removal programs, and I encourage you to participate in these.
This orange plastic rectangle is a Bycatch Reduction Device (BRD) used to keep terrapins out of crab traps – but not crabs.
Photo: Rick O’Connor
A bigger issue for Florida is the land-based predators. As we moved closer and closer to the salt marshes, we built bridges and roads that allowed land-based predators to reach the nesting beaches they previously did not have access to. Raccoons in particular are a big problem, depredating as many as 90% of the terrapin nests. Poaching for the pet trade is rising and FWC is working on this. Several major arrests have been made in Florida in recent years. It is illegal to sell Florida turtles, so do not buy them if you see them being sold somewhere. Report the activity to FWC.
Due to all of this, terrapins afford some form of protection in each of the coastal states where they exist. Some list them as “endangered” or “threatened”. In Florida, they do not have this label, but they are protected by FWC. No one is allowed to have more than two in their possession, and you are not allowed to have any eggs.
It is an amazing turtle. I currently conduct a citizen science program monitoring them in the western panhandle. I have a lot of eager volunteers wanting to see their first one in the wild. I hope they do soon. I hope they hang around long enough for everyone to see one in the wild.
As we embrace the marine life of the Gulf of Mexico during this year of “Embracing the Gulf”, we are currently hooked on worms. In the last article we talked about the gross and creepy flatworms. Gross because they are flat, pale in color, only have a mouth so they have to go to the bathroom using it – and creepy in that many of them are parasites, living in the bodies over vertebrates (particularly fish) and that is just creepy. You may ask why would we even “embrace” such a thing? Well… because they do exist and most of us know nothing about them.
A nemertean worm.
Photo: Okinawa Institute of Science
This week we continue with worms. We continue with a different kind of flatworm. They are not as gross, but maybe a little creepy. They are called nemertean worms and I am pretty sure (a) you have never heard of them, and (b) you have never seen one. So why “embrace” these? Well… again it is education. They do exist, and one day you MAY see one – and know what you are looking at.
Nemerteans are flatworms. They are usually pale in color but a different from the classis fluke or tapeworm in a couple of ways.
1) They do have a way for food to enter and another for waste to leave, what we call a complete digestive tract – and that’s nice.
2) They have this long extension connected to their head called a proboscis. Many of them have a dart at the end they can use to kill their prey – and that’s creepy.
3) And as mentioned, most are carnivores, feeding on small invertebrates – and that’s okay.
We rarely see them because they are nocturnal – hiding under rocks, shells, seaweed during the day and hunting at night. Most are about eight inches long but some in the Pacific reach almost eight feet!
I would put that in the creepy file.
As we said, they are usually pale in color, though some may have yellow, orange, red, or even green hues to them. Their heads are spade shaped and, again, hold a retracted proboscis. This proboscis can be over half the length of the worm. At the end is a stylet (a dart) which they can use to stab their prey (small invertebrates). They can stab repeatedly, like using a knife, – they may stab and grab, like using a claw – or they may be a species that has toxin and kills their prey that way.
Some would add this to the creepy file as well. A long pale worm, moving at night, extending a long proboscis when they get near you with a sharp dart at the end they essentially “sting” you like a bee.
But we NEVER hear about such things with humans. They hunt small invertebrates like amphipods, isopods, and things like that. If you picked one up, would it stick the dart in you? My hunch would be yes – I honestly don’t know, I have only seen one to two in the 35+ years I have been teaching marine science and I did not pick them up. I have never met anyone who has and have never read “DON’T PICK THESE UP – VERY DANGERSOUS”. So, my hunch is that it would not be very painful at all.
But don’t take my word for it – again, I have rarely seen one… so, don’t pick them up 😊
There are about 650 species of nemertean worms in the world, 22 live in the Gulf of Mexico, and 16 live in the northern Gulf (near us). They are basically marine, move across the environment on their slime trails, seeking prey primarily by the sense of smell at night. Unlike the flukes and tapeworms, there are male and females in this group. They fertilize their eggs externally to make the next generation of these harpooning hunters of the Gulf.
I don’t know if you will ever come across one of these. You will know it by the flat body, pale color, and spade-shaped head, but I think it would be pretty neat to find one. There are more worms to learn about in the Gulf of Mexico, but we will do that in another edition.
Black Skimmers foraging for fish. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Black Skimmers and Least Terns, state listed species of seabirds, have returned along the coastal areas of the northern Gulf of Mexico! These colorful, dynamic birds are fun to watch, which can be done without disturbing the them.
Shorebirds foraging. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Black Skimmer with a fish. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
What is the difference between a seabird and shorebird?
Among other behaviors, their foraging habits are the easiest way to distinguish between the two. The seabirds depend on the open water to forage on fish and small invertebrates. The shorebirds are the camouflaged birds that can found along the shore, using their specialized beaks to poke in the sandy areas to forage for invertebrates.
Both seabirds and shorebirds nest on our local beaches, spoil islands, and artificial habitats such as gravel rooftops. Many of these birds are listed as endangered or threatened species by state and federal agencies.
Juvenile Black Skimmer learning to forage. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Adult black skimmers are easily identified by their long, black and orange bills, black upper body and white underside. They are most active in the early morning and evening while feeding. You can watch them swoop and skim along the water at many locations along the Gulf Coast. Watch for their tell-tale skimming as they skim the surface of the water with their beaks open, foraging for small fish and invertebrates. The lower mandible (beak) is longer than the upper mandible, this adaptation allows these birds to be efficient at catching their prey.
Least Tern “dive bombing” a Black Skimmer that is too close to the Least Tern nest. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Adult breeding least terns are much smaller birds with a white underside and a grey-upper body. Their bill is yellow, they have a white forehead and a black stripe across their eyes. Just above the tail feathers, there are two dark primary feathers that appear to look like a black tip at the back end of the bird. Terns feed by diving down to the water to grab their prey. They also use this “dive-bombing” technique to ward off predators, pets and humans from their nests, eggs and chicks.
Least Tern with chicks. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Both Black Skimmers and Least Terns nest in colonies, which means they nest with many other birds. Black skimmers and Least Terns nest in sandy areas along the beach. They create a “scrape” in the sand. The birds lay their eggs in the shallow depression, the eggs blend into the beach sand and are very hard to see by humans and predators. In order to avoid disturbing the birds when they are sitting on their nests, known nesting areas are temporarily roped off by Audubon and/or Florida Fish and Wildlife Conservation Commission (FWC) representatives. This is done to protect the birds while they are nesting, caring for the babies and as the babies begin to learn to fly and forage for themselves.
Threats to these beautiful acrobats include loss of habitat, which means less space for the birds to rest, nest and forage. Disturbances from human caused activities such as:
- walking through nesting grounds
- allowing pets to run off-leash in nesting areas
- feral cats and other predators
- driving on the beach
- fireworks and other loud noises
Audubon and FWC rope-off nesting areas to protect the birds, their eggs and chicks. These nesting areas have signage asking visitors to stay out of nesting zones, so the chicks have a better chance of surviving. When a bird is disturbed off their nest, there is increased vulnerability to predators, heat and the parents may not return to the nest.
Black Skimmer feeding a chick. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
To observe these birds, stay a safe distance away, zoom in with a telescope, phone, camera or binoculars, you may see a fluffy little chick! Let’s all work to give the birds some space.
Special thanks to Jan Trzepacz of Pelican Lane Arts for the use of these beautiful photos.
To learn about the Audubon Shorebird program on Navarre Beach, FL check out the Relax on Navarre Beach Facebook webinar presentation by Caroline Stahala, Audubon Western Florida Panhandle Shorebird Program Coordinator:
In some areas these birds nest close to the road. These areas have temporarily reduced speed limits, please drive the speed limit to avoid hitting a chick. If you are interested in receiving a “chick magnet” for your car, to show you support bird conservation, please send an email to: firstname.lastname@example.org, Please put “chick magnet” in the subject line. Please allow 2 weeks to receive your magnet in the mail. Limited quantities available.