by Rick O'Connor | Oct 18, 2024
We are going to begin this series of articles with a “creature” that some do not consider alive – viruses. While studying marine science in college, and my early days as a marine science educator, there was a debate as to whether viruses were actually alive and should be included in a biology course. A quick glance at the textbooks of the time shows they were often omitted – though they were included in my microbiology class. Why were they omitted? Why did some consider them “non-living creatures”?
The coronavirus next to a strand of DNA.
Image: Florida International University.
Well, we always began biology 101 with the characteristics of life. Let’s scan these characteristics and see where viruses fit.
- Made of cells. This is not the case for viruses. A typical cell will include a cell membrane filled with cytoplasm and a nucleus, which is filled with genetic material (chromosomes containing DNA and RNA). An examination of a virus you will find it is either DNA or RNA encapsulated in a protein coat. It is “nucleus-like” in nature. Most cells run between 10-20 microns in size. A typical nucleus within a mammal cell will run between 5-10 microns. A typical virus would be 0.1 microns – these are tiny things – MUCH smaller than a cell.
- Process energy. Nope – they do not. Most cells utilize energy during their metabolism. Viruses do not do this.
- Growth and development. Nope again. They “spread”, which we discuss in a moment, but they do not grow. We are now 0-3.
- Homeostasis. Homeostasis is the movement of material and environmental control to remain stable – and viruses do not do this.
- Respond to stimuli. Yes… here is one they do. Studies show that viruses do respond to their chemical and physical environment.
- Metabolism. As mentioned above, this would be a no.
- Adaptation. Studies show that through very rapid reproduction they can adapt to the changing environment they are in.
- Reproduce. This is a sort of “yes/no” answer. They do reproduce (as we say – “spread”) but they do not do this on their own. They invade the nucleus within the cells of their host and replace their genetic material with that of the host creature. Then, during cell replication within the host, new viruses are produced and “spread”.
So, you can see why there is a debate. Of the eight common characteristics of life, viruses possess only three – and one of those can only be achieved with the assistance of a host creature. Now the question would be – do be labeled as a “creature” do you need ALL eight characteristics of life? Or only a few? And if only a few – how many? Because of this most biologists do not consider them alive.
During one class when we were discussing this a student made a comment – “don’t we KILL viruses? If so, then it must be alive first”. Point taken – and we should understand the phrase “kill a viruses” does not mean literally killing. It is a phrase we use. Though some argue we do kill viruses and thus…
Another point we could make here is that all life on the planet has been classified using a system developed by the Swedish botanist Carlos Linnaeus. Each creature is placed in a kingdom, then phylum, class, order, family, genus, and eventually a species name is given. We “name” the creature using its genus and species name – Homo sapiens for example. We do not see this for viruses.
All that said, both the National Oceanic and Atmospheric Administration and the National Institute of Health indicate the “most common form of life in the sea are viral-like particles” – with over 10 million in a single drop of seawater. We will leave the debate here. Your thoughts?
by Sheila Dunning | Oct 4, 2024
Coastal wetlands are some of the most ecologically productive environments on Earth. They support diverse plant and animal species, provide essential ecosystem services such as stormwater filtration, and act as buffers against storms. As Helene showed the Big Bend area, storm surge is devastating to these delicate ecosystems.
Hurricane Track on Wednesday evening.
As the force of rushing water erodes soil, uproots vegetation, and reshapes the landscape, critical habitats for wildlife, in and out of the water, is lost, sometimes, forever. Saltwater is forced into the freshwater wetlands. Many plants and aquatic animal species are not adapted to high salinity, and will die off. The ecosystem’s species composition can completely change in just a few short hours.
Prolonged storm surge can overwhelm even the very salt tolerant species. While wetlands are naturally adept at absorbing excess water, the salinity concentration change can lead to complete changes in soil chemistry, sediment build-up, and water oxygen levels. The biodiversity of plant and animal species will change in favor of marine species, versus freshwater species.
Coastal communities impacted by a hurricane change the view of the landscape for months, or even, years. Construction can replace many of the structures lost. Rebuilding wetlands can take hundreds of years. In the meantime, these developments remain even more vulnerable to the effects of the next storm. Apalachicola and Cedar Key are examples of the impacts of storm surge on coastal wetlands. Helene will do even more damage.
Many of the coastal cities in the Big Bend have been implementing mitigation strategies to reduce the damage. Extension agents throughout the area have utilized integrated approaches that combine natural and engineered solutions. Green Stormwater Infrastructure techniques and Living Shorelines are just two approaches being taken.
So, as we all wish them a speedy recovery, take some time to educate yourself on what could be done in all of our Panhandle coastal communities to protect our fragile wetland ecosystems. For more information go to:
https://ffl.ifas.ufl.edu/media/fflifasufledu/docs/gsi-documents/GSI-Maintenance-Manual.pdf
https://blogs.ifas.ufl.edu/news/2023/11/29/cedar-key-living-shorelines/
by Thomas Derbes II | Jun 21, 2024
In Part 1 of The Estuary’s Natural Filtration System article, we discussed the major contributors to natural filtration inside of the estuary. These examples included oysters, marsh plants, and seagrasses. In Part 2, we will discuss the smaller filter-feeding organisms including tunicates, barnacles, clams, and anemones.
Tunicates
Pleated Sea Squirt – Photo Credit: Don Levitan, PH.D. FSU
Tunicates, also known as sea squirts, are very interesting marine invertebrates and can be easily confused for a sponge. There are many different types of tunicates in the estuaries and can be either solitary or colonial. You might’ve seen these at an aquarium attached to different substrates, and when removed from the water, their name sea squirt comes into play. Tunicates have a defense mechanism to shoot out the water inside their body in hopes of being released by any predator.
Tunicates are filter feeders and intake water through their inhalant siphons and expel waste and filtered water through their exhalant siphons. Tunicates can filter out phytoplankton, algae, detritus, and other suspended nutrients. The tunicate produces a mucus that catches these nutrients as it passes through, and the mucus is then conveyed to the intestine where it is digested and absorbed.
An invader to the Gulf of Mexico, the Pleated Sea Squirt (Styela plicata), hitched rides on the hulls of ships and found the Gulf of Mexico waters very favorable. You can sometimes spot these organisms on ropes that have been submerged for a long period of time in salty waters. Even though they are non-native, these sea squirts can filter, on average, 19 gallons of water per day.
Barnacles
Barnacles along the seashore is a common site for many.
Photo: NOAA
One organism that seems ubiquitous worldwide is the barnacle (Genus Semibalanus and Genus Lepas). The Genus Semibalanus contains the common encrusting barnacle we are accustomed to seeing in our waterways along pilings, submerged rocks, and even other animals (turtles, whales, crabs, and oysters). The Genus Lepas contains Gooseneck Barnacles and can be seen attached to flotsam, floating organic debris, and other hard surfaces and have a stalk that attaches them to their substrate. Interesting fact, certain gooseneck barnacle species are eaten in different parts of the world.
This image from a textbook shows the internal structure of a barnacle. Notice the shrimplike animal on its back with extendable appendages (cirri) for feeding.
Image: Robert Barnes Invertebrate Zoology.
Barnacles have over 2,100 species, are closely related to crabs and lobsters, and are a part of the subphylum Crustacea. At first glance, you might not think a barnacle is closely related to crabs, but when you remove the hard plates surrounding it, the body looks very similar to a crab. Barnacles also have life cycle stages that are similar to crabs; the nauplius and cyprid developmental stages. Inside of the hard plates is an organism with large feather-like appendages called cirri. When covered by water, the barnacles will extend their cirri into the water and trap microscopic particles like detritus, algae, and zooplankton. Barnacles are at the mercy of tides and currents, which makes quantifying their filtering ability difficult.
Hard Clams
Clams of North Florida – UF/IFAS Shellfish
Even though not as abundant in the Florida Panhandle as they were in the 1970’s – 1980’s, hard clams (Mercenaria mercenaria and M. campechiensis) can still be found in the sand along the shoreline and near seagrass beds. These clams are also known as Quahogs and are in the family Veneridae, commonly known as the Venus clam family, and contain over 500 living species. Most of the clams in the family Veneridae are edible and Quahogs are the types of clams you would see in a clam chowder or clam bake.
Being the only bivalve on this list does not make it any less important than the oyster or scallop on Part 1’s list. In fact, a full-grown adult Southern Quahog clam can filter upwards of 20 gallons of water per day and have a lifespan of up to 30 years. Clams also live a much different lifestyle than their oyster and scallop cousins. Clams spend the majority of their life under the sand. Their movement under the sand helps aerate and mix the soil, which can sometimes stimulate seagrass growth.
Right outside the Florida Panhandle and in the Big Bend area, Quahog clams are commercially farmed in Cedar Key. Southern Quahog clams are also being used for restoration work in South Florida. Clams are being bred in a hatchery and their “seed” are being released into Sarasota Bay to help tackle the Red Tide (Karenia brevis) issue. According to the project’s website, they have added over 2 million clams since 2016, and the clams are filtering over 20 million gallons of seawater daily.
Anemones
Tube-Dwelling Anemone Under Dissection Scope – UF/IFAS Shellfish
Anemones are beautiful Cnidarians resembling an upside-down, attached jellyfish, which couldn’t be closer to the truth. The phylum Cnidaria contains over 11,000 species of aquatic animals including corals, hydroids, sea anemones, and, you guessed it, jellyfish. Anemones come in many different shapes and sizes, but the common estuary anemones include the tube-dwelling anemone (Ceriantheopsis americana) and the tricolor anemone (Calliactis tricolor), also known as the hitchhiking anemone. If you have ever owned a saltwater aquarium, you might have run into the pest anemone Aiptasia (Aiptasia sp.).
Anemones filter feed with their tentacles by catching plankton, detritus, and other nutrients as the tide and current flows. The tentacles of the anemone are lined with cnidocytes that contain small amounts of poison that will stun or paralyze the prey. The cnidae are triggered to release when an organism touches the tentacles. If the anemone is successful in immobilizing the prey, the anemone will guide the prey to their mouth with the tentacles. Just like the barnacle, anemones are at the mercy of the tides and currents, and filtration rates are hard to calculate. However, if you ever see an anemone with food around, they move those tentacles to and from their mouths quickly and constantly!
In Parting
As you can see, there are many different natural filters in our estuary. Healthy, efficiently filtering estuaries are very important for the local community and the quality of the waters we love and enjoy. For more information on our watersheds and estuaries and how to protect them, visit Sea Grant’s Guide To Estuary-Friendly Living.
by Ray Bodrey | Jun 3, 2024
The University of Florida/IFAS Extension & Florida Sea Grant faculty are reintroducing their acclaimed “Panhandle Outdoors LIVE!” series on St. Joseph Bay. This ecosystem is home to some of the richest concentrations of flora and fauna on the Northern Gulf Coast. This area supports an amazing diversity of fish, aquatic invertebrates, turtles and other species of the marsh and pine flatwoods. Come learn about the important roles of ecosystem!
Registration fee is $40. You must pre-register to attend.
Registration link: https://www.eventbrite.com/e/panhandle-outdoors-live-st-joseph-bay-by-land-sea-tickets-906983109897
or use the QR code:
Meals: Lunch, drinks & snacks provided (you may bring your own)
Attire: outdoor wear, water shoes, bug spray and sunscreen
*If afternoon rain is in forecast, outdoor activities may be switched to the morning schedule
Held at the St. Joseph Bay State Buffer Preserve Lodge: 3915 State Road 30-A, Port St. Joe
| 8:30 – 8:35 Welcome & Introduction – Ray Bodrey, Gulf County Extension (5 min) |
| 8:35 – 9:20 Diamondback Terrapin Ecology – Rick O’Connor, Escambia County Extension |
| 9:20 – 10:05 Exploring Snakes, Lizards & the Cuban Tree Frog – Erik Lovestrand, Franklin County Extension |
| 10:05 – 10:15 Break |
| 10:15 – 11:00 The Bay Scallop & Habitat – Ray Bodrey, Gulf County Extension |
| 11:00 – 11:45 The Hard Structures: Artificial Reefs & Derelict Vessel Program – Scott Jackson, Bay County Extension |
| 11:45 – Noon Question & Answer Session – All Agents |
| Noon – 1:00 Pizza & Salad! |
| 1:00 – 1:20 Introduction to the Buffer & History – Buffer Preserve Staff |
| 1:20 – 2:20 Tram Tour – Buffer Preserve Staff |
| 2:20 – 2:30 Break |
| 2:30 – 3:00 A Walk in the Mangroves – All Agents |
| 3:00 – 3:15 Wrap up & Adjourn – All |
by Thomas Derbes II | May 10, 2024
The Panhandle of Florida is home to many estuaries along the coast, from the Escambia Bay System in the west to the Apalachicola Bay System in the east. These estuaries are very important and are the intersection where rivers (fed from their respective watersheds) meet the Gulf of Mexico and contain many different organisms that help filter the waters before they reach the Gulf. These organisms include oysters, marsh plants, seagrasses, scallops, tunicates, and other invertebrates. In this two-part article, we will explore marsh plants, seagrasses, oysters, and scallops.
Marsh Plants
Marsh Plants is a broad term for a family of grasses that lines the shore and contain grasses like Smooth Cordgrass (Spartina alterniflora), Saltgrass (Distichlis spicata), and Gulf Cordgrass (Spartina spartinae). These plants help trap sediments before they enter the estuary and are excellent at erosion prevention. When the water encounters the plants, it slows the flow, and this allows for sediments to collect. Marsh Plants are a great tool for shoreline restoration and are a major part of the Living Shorelines Program. The roots of the plants are also very efficient at removing nutrient pollutants like excess nitrogen and phosphorus which are major influencers in eutrophication. Marsh Plants also absorb carbon dioxide from the atmosphere and have been tabbed as “superstars of CO2 capture and storage.” (CO2 and Marsh Plants)
Marsh Grass and Oyster Reef in Apalachicola, Florida – Thomas Derbes II
Seagrasses
Seagrasses are different than Marsh Grasses (seagrasses are ALWAYS submerged underwater), but they offer some of the same ecological services as Marsh Grasses. The term seagrasses include Turtle Grass (Thalassia testudinum), Shoal Grass (Halodule wrightii), Widgeon Grass (Ruppia maritima), and Manatee Grass (Syringodium filiforme) to name a few. Seagrasses help maintain water clarity by trapping suspended sediments and particles with their leaves and uptake excess nutrients in their roots. Seagrasses are very efficient at capturing carbon, capturing it at rates up to 35 times faster than tropical rainforests. (Carbon Capture and Seagrasses) They also provide habitat for crustaceans, fish, and shellfish (which can filter the water too) and food for other organisms like turtles and manatees.
Grassbeds are also full of life, albeit small creatures.
Photo: Virginia Sea Grant
Oysters
Crassostrea virginica (or as we know them, the Eastern oyster) is a native species of oyster that is commonly found along the eastern coast of the USA, from the upper New England states all the way to the southernmost tip of Texas. Eastern oysters are prolific filter feeders and can filter between 30-50 gallons of water per day. As filter feeders, they trap nutrients like plankton and algae from the environment. In areas of high eutrophication, oysters can be very beneficial in clearing the waters by trapping and consuming the excess nutrients and sediments and depositing them on the bottom as pseudo-feces. With oyster farms popping up all over the Gulf Coast, the filtering potential of estuaries is on the rise. (Between the Hinge)
Oysters, The Powerful Filterers of the Estuary – Thomas Derbes II
Scallops
Bay Scallops (Agropecten irradians) were common along the whole Florida Gulf Coast, but their numbers have taken a recent decline and can only be found in abundance in the estuaries to the east of St. Andrews Bay in Panama City, Florida. Scallops make their home in seagrass beds and are filter feeders. While scallops do not contain the filtering potential of an oyster (scallops filter 3 gallons of water per day as an adult), they are still a key part of filtering the estuary. Just like oysters, scallops feed off of the suspended particles and plankton in the water column and deposit them as pseudo-feces on the bottom. The pseudo-feces also help provide nutrients to the seagrasses below.
Bay Scallop.
Photo: FWC
I hope you enjoyed this first article on filterers in the estuary system. While oysters are known as the filterers of the estuary, I hope this has opened your eyes to the many different filterers that call our estuary home. Stay tuned for Part 2!
by Dana Stephens | May 3, 2024
Understanding Salinity in Northwest Florida’s Waters with a Family Activity
Dana Stephens, 4-H Agent
Salinity is the amount of total dissolved salts in water. This includes all salts not just sodium chloride, or table salt. Salinity is important in aquatic environments as many flora and fauna depend on salt and the level of dissolved salts in the water for survival. People interested in the composition of water frequently measure chemical and physical components of water. Salinity is one of the vital chemical components measured and often measured by a device determining how readily electrical conductance passes between two metal plates or electrodes. These units of electrical conductance, the estimate of total dissolved salts in water, is described in units of measurement of parts per thousand (PPT).
At the large scale, Earth processes, such as weathering of rocks, evaporation of ocean waters, and ice formation in the ocean, add salt to the aquatic environment. Earth processes, such as freshwater input from rivers, rain and snow precipitation, and ice melting, decrease the concentration of salt in the aquatic environment. Anthropogenic (human-induced) activities, such as urbanization or atmospheric deposition, can also contribute to changes in salinity.
Salinity and changes in salinity affect how water moves on Earth due to contrasts in the density of water. Water containing no dissolved salts is less dense than water containing dissolved salts. Density is weight per volume, so water with no dissolved salts (less dense) will float on top of water with dissolved salts (denser). This is why swimming in the ocean may feel easier than swimming in a lake because the denser water provides increased buoyancy.
Northwest Florida is a unique place because we have a variety of surface waters that range in salinity. There are ponds, lakes, streams, rivers, and springs, which have no to low salinity levels (0 to 0.5 PPT), and commonly referred to as freshwater systems. We house six estuaries—Perdido Bay, Pensacola/Escambia Bay, Choctawhatchee Bay, St. Andrews Bay, St. Joseph Bay, and Apalachicola Bay. Estuaries are bodies of water with freshwater input(s) (e.g., rivers) and a permanent opening to the ocean (e.g., Destin Pass in the Choctawhatchee Bay). Estuarine waters are termed brackish water (0.5 to 30 PPT) due to the dynamic changes in salinity at spatial and temporal scales. Waterbodies with an even more dynamic change in salinity are the coastal dune lakes Northwest Florida’s Walton and Bay Counties. Coastal dune lakes are waterbodies perched on sand dunes that intermittently open and close to the Gulf of Mexico. Sometimes these waterbodies are fresh and sometimes they have the same salinity as the Gulf of Mexico, like after a large storm event. Finally, the Gulf of Mexico, or ocean, has the highest salinity (> 30 PPT) among the waterbodies of Northwest Florida.
Here is an educational activity for the family to explore salinity and how salinity differs among Northwest Florida waters.
