by Rick O'Connor | Apr 14, 2018
Shoal grass. One of the common seagrasses in Florida.
Photo: Leroy Creswell
For many, it really does not matter. But is there a difference? Yes… there is. Seagrass is what typically washes ashore on the Sound side – seaweed is what we typically see on the Gulf.
So what is the difference?
Seagrasses are actually grasses. They are true plants in the sense they have roots, stems, and leaves. They also produce flowers, but they are so small it is very hard to see them. Pollen and seed dispersal is via the currents. What the observer sees when snorkeling in seagrass meadows are the leaves – in this case called blades. The stems run horizontal beneath the sand, as many grasses in our lawns do. These are called rhizomes, and the roots extend from them. Turtle grass and Shoal grass are the two most common types we have here.
Seaweeds on the other hand, are not true plants because they lack roots, stems, and leaves. They are often called algae and must be submerged in water in order to absorb it. They are either float and drift in the currents, or can attach to hard objects on the seafloor using a structure called a holdfast. June grass and Sargassum are two common types that drift ashore.
So why don’t seagrasses grow in the Gulf?
Like all plants, seagrasses need sunlight. At least 25% of the sunlight reaching the surface must reach the bottom for them to photosynthesize. Near the shore, there is enough sunlight for seagrass, but they cannot tolerate the larger waves that our nearshore Gulf produces – thus they are restricted to the quieter waters of the Sound. We do have seagrasses growing in Big Lagoon, Old River, parts of Pensacola Bay, and even in some of the local bayous. This ecosystem is important to the overall health of our bay. It is known that 80-90% of the commercially and recreationally important finfish and shellfish require seagrasses, or salt marshes, for at least part of their life cycle – so they are important economically as well.
Seaweeds also need sunlight. In rocky areas, you can find them attached in sunlit waters. Much of our area is sand, so we do not see as many forms of seaweed as they do in the Keys or in California. However, we do have floating forms.
March is “Seagrass Awareness Month”. Many people provide opportunities to educate locals about our seagrasses and the issues they are facing. Excessive run-off from parking lots, ramps, homes, etc. – increase the turbidity and decrease the salinity of the water – both of which are detrimental to seagrass health. This run-off also contains pollutants that are problematic – particularly nutrients from fertilizers. The fertilizers trigger algal blooms which block sunlight and, in some cases, smoother the surface of the grass blades. Then there is prop scarring. The shallow waters where they live are also popular spots for boaters to visit. The propeller scarring leaves open tracts throughout the seagrass meadows and, unlike some grasses in our yards, can take years – even decades – to recover. There has been significant loss of seagrass all across the Gulf region, including Pensacola Bay. The loss of seagrass have also affected species such as bay scallop and horseshoe crabs. There are signs of recovery and we need to continue reducing our impact to keep this trend going. Florida Friendly Landscaping, Clean Boater practices, and Living Shorelines are some methods that can help. Contact your local County Extension Office to learn more about these programs.
by Rick O'Connor | Feb 16, 2018
As a young boy growing up here in the panhandle, I had heard of this thing called a manatee – but had never seen one. They came more into the light when I was a teenager and becoming interested in marine biology. I was the president of the high school marine biology club and one of our goals was to raise money for a trip to Crystal River to snorkel with them. The Save the Manatee Club originated in that time trying to bring more awareness to the plight of this endangered Floridian and at one point, Jimmy Buffett had led the way.
I had learned a lot about them, found out their original range was from North Carolina south to the Caribbean and the entire Gulf of Mexico, but were now down to about 1000 animals and those were found in Florida. Eventually I did get to see manatees, and have snorkeled with them many times, but still thought of them as a south Florida animal – rarely found in the panhandle.
Manatee swimming in Big Lagoon near Pensacola.
Photo: Marsha Stanton
Then the recent news report – two dead manatees in the last two weeks. One washed ashore in Okaloosa county and the other in Escambia. Probably victims of the recent cold fronts. It is not unheard of finding manatees in the panhandle in recent years. I recall since the 1990’s a manatee seen in Bayou Texar in Pensacola. In another year, one was seen near Ft. Pickens. My son worked at a local marina and saw at least one a year there. There have been so many seen in the Mobile Bay area that Dauphin Island Sea Lab now has a Manatee Watch program. There are about 40 individuals that now visit Wakulla Springs. In addition, this summer there were two separate groups living in the Pensacola area. One group was residing near Gulf Breeze and a second group of about eight animals was frequently seen near Perdido Key. These once rare animals in the panhandle are now being found each year, and sometimes in groups.
What is going on?
Why are manatees beginning to visit our area?
Your first hunch would be climate change. Manatees are marine mammals but unlike their dolphin cousins their blubber layer is not as thick and they must seek warm water refuge during the winter months. When water temperatures drop below 67°F, they locate the warm water springs found in central Florida – or move south Florida where the water remains comfortable year round. If they are remaining here, could the average water temperatures have warmed enough for them to make this move?
Along this same line, mangroves are now being found in the panhandle. Both red and black mangroves have been found growing in local estuaries. In the Apalachicola area there have been quite a few located. In the western panhandle there a few individuals here and there. Further west they are found on the islands of Mississippi and have been in the Chandeleurs for many years now. Later this spring Florida Sea Grant will be conducting surveys in each county to see where these tropical trees may be growing.
A small red mangrove growing in Big Lagoon near Pensacola FL
Photo: Rick O’Connor
And most recently are sightings of snook, a south Florida fish that have, though rare, been seen in the northern Gulf of Mexico. No doubt this Januarys hard freezes probably killed the mangroves that were here, and probably the two manatees washed ashore recently, but it will be an interesting time to see what other tropical species begin their slow migration northward. If it does happen, what will that mean? How will these changes impact local ecosystems? At this point, I am not sure if it will happen or, if it does, how fast – but it will be interesting.
by Erik Lovestrand | Feb 2, 2018
Sorting and re-caging take place on-site at the lease
Photo: Erik Lovestrand
There are a number of parallels than can be drawn between shellfish farming and traditional forms of agriculture that take place on the land. The most obvious similarities are the amount of hard work, grit and faith that are required of the farmer on land or sea. In spite of this there are many “salty” farmers in the Florida Panhandle who have mustered the faith requirement and are now putting in the hard work necessary to help build this budding industry in the Southeastern U.S.
Market demand for quality oysters has continued to outstrip available supplies for several years of late. This has been due in part to better marketing strategies employed by growers as well as clientele becoming aware of the health benefits of fresh oysters; a great supply of important vitamins and minerals, including vitamin C and B vitamins, zinc, selenium and iron. However, supply/demand ratios are not the only important factor in developing a thriving oyster aquaculture industry. Also required, is the necessary infrastructure to support the grower’s equipment needs, enough sources of baby oyster “seed”, a reliable refrigerated transportation network for live shellfish, and the support of regulatory agencies in making water leases available in suitable growing areas.
Fortunately, the stars seem to be aligning for many of these industry-growth necessities and the business of oyster farming is gaining a firmer foundation to build upon. One of the important milestones for Florida was the approval of “full-water-column” leases, which allows the use of floating oyster cages or bags. Previously, oysters were required to be grown on the bay bottom and this made them susceptible to higher levels of predation from crabs and snails and severe biofouling (barnacles and algae) on the exterior of the mesh bags. Heavy biofouling reduces the water flow through the oyster’s growing environment, thus the available food for this filter feeding bivalve.
One critical need for this industry is the availability of quality “seed” (baby oysters) to put in the growing waters. Seed oysters are supplied by hatcheries where oyster brood stocks are spawned and babies are raised to the necessary age for grower needs. Some growers use baby oyster larvae that have not settled and attached yet. These “eyed larvae” are put in a tank with old oyster shell and allowed to attach on the shells, which are then deployed at a lease site. Other growers use seed that has already attached to a small particle of crushed shell and are sold as individual oysters to be placed in grow-out bags or cages. The more recent development of oyster stocks with 3 sets of chromosomes (triploids) have provided growers with an oyster that gets to market size faster. Triploid oysters are infertile and do not use energy for spawning, thereby putting more energy into shell and tissue growth. Federal and state laws also govern where growers can buy their seed in an effort aimed at stopping the spread of shellfish disease from one body of water to another (i.e. Atlantic to Gulf of Mexico, etc.).
Even if all of the hardware and infrastructure is in place, there is still one other factor that plays a significant role in whether an oyster farmer will be successful. Just like the dairy farmer, the cattle rancher, the cotton or peanut grower, or the blueberry producer; backbreaking labor is necessary for many stages of the production cycle. Oyster growers work their leases either bending over the gunnels of a boat or actually being in the water, lifting heavy bags or cages of shellfish, sorting by size, re-caging, and moving lots of materials to and from the lease area. True grit and a dogged determination to stay on top of things, regardless of unpleasant conditions, are vital to raising a successful crop of oysters. And by the way, don’t forget that Mother Nature will have the final word. As all farmers know, they are required to be a good listener when she speaks.
by Rick O'Connor | Jan 5, 2018
Last year I began a series of articles on the Gulf of Mexico. They focused on the physical Gulf – water, currents, and the ocean floor. This year the articles will focus on the life within the Gulf, and there is a lot of it.
Single celled algae are the “grasses of the sea” and provide the base of most marine food chains.
Photo: University of New Hampshire
We will begin with the base of food web systems, the simplest creatures in the sea. The base of food systems are generally plants and the simplest of these are the single celled plants. Singled celled plants are a form of algae, not true plants in the sense we think of them, but serving the same role in the environment – which is the production of much needed energy.
What these single celled algae need to survive is the same as the more commonly known plants – sunlight, water, carbon dioxide, oxygen, and nutrients.
Sunlight is difficult for marine plants because sunlight only penetrates so deep. Therefore, marine plants and algae must live in shallow water, or have some mechanism to remain near the surface in the open sea. In relation to their overall body volume, smaller creatures have more surface area than larger ones. More surface area helps resist sinking and the smallest you can get is a single cell. Thus, most marine algae are single celled. Many single celled plants are encased in transparent shells that have spines and other adaptations to assist in increasing their surface area and keeping them near the surface. Some actually have drops of oil (buoyant in water) making it even easier to stay near the surface. These small floating algae drift in the surface currents, and drifting organisms are called plankton. Plankton that are “plant-like” are called phytoplankton.
The next needed resource is water; the Gulf and Bay are full of it. However, saltwater is not what they need – freshwater is, so they must desalinate the water before absorbing it. They can do this by adjusting the solutes within their cytoplasm. The greater the ratio of surface area is to volume, the more diffusion of solutes can take place – thus these small phytoplankton are very good at diffusing resources in (like water and carbon dioxide) and expelling waste (like ammonia and oxygen).
Image showing how deep different colors of light penetrates in the sea.
Image: Minnesota Sea Grant
Carbon dioxide and oxygen are dissolved in seawater and, like water, are diffused into the phytoplankton. Warmer water holds less oxygen so there would be a tendency to have more phytoplankton in colder waters. However, warmer waters are so because there is generally more sunlight, a needed resource. The colder, sunlit, surface waters off some coasts – such as California – have higher amounts of dissolved oxygen and are some of the most productive areas in the ocean. Phytoplankton can also serve as “carbon sinks” by removing carbon dioxide dissolved in the seawater coming from the atmosphere. However, this may not be the answer to excessive CO2 in the atmosphere because, like all creatures, you can only consume so much “food”. Excessive loads of carbon dioxide will not be consumed.
Finally, there is the need for nutrients. All plants need fertilizer. Nutrients in the sea come from either run-off from land, or decayed material from the ocean floor. Much of the nutrients are discharged into the Gulf by run-off from land. Because of this, much of the phytoplankton are congregated nearshore where rivers meet the sea. We think of marine life as equally distributed across the ocean, but in act it is not, there is more life nearshore. For the compost on the ocean floor to be of used by phytoplankton, it must reach the surface. This happens where a current called an upwelling occurs. Upwellings rise from the seafloor bringing with them the nutrients. Where upwellings occur, the seawater is colder, and sunlight abundant, you have the greatest concentration of marine life – all fueled by these phytoplankton.
In the Gulf, one of the most productive places is “the plume”, where the Mississippi River discharges. This massive river brings water, sediments, and nutrients, from most of the continent. The large plankton blooms attract massive schools of plankton consuming fish, predatory fish, sea birds, and marine mammals.
In the next post, we discuss some of the different phytoplankton that inhabit our coastal waters and the amazing things they do.
A satellite image showing the sediment plume of the Mississippi River. This plume brings with it nutrients that fuel plankton blooms.
Image: NASA satellite
References
Kirst G.O. (1996) Osmotic Adjustment in Phytoplankton and MacroAlgae. In: Kiene R.P., Visscher P.T.,
Keller M.D., Kirst G.O. (eds) Biological and Environmental Chemistry of DMSP and Related Sulfonium Compounds. Springer, Boston, MA
by Rick O'Connor | Oct 31, 2017
In our continuing battle with invasive species, northwest Florida is now home to an invasive lizard. Known as both the Cuban and Brown Anole, this animal has been reported from Big Lagoon, East Hill, North Hill, and Gulf Breeze in the Pensacola area. I have seen it at almost every rest area on I-10 between here and Gainesville and in large numbers at some local nurseries.
This Cuban Anole was photographed on a public hiking trail near Perdido Key.
Photo: Jerry Patee
Who is this new invader to our area?
We will start with “new”.
Compared to the rest of the state, it is new. First reported in 1887, this lizard hitchhiked over from its native Cuba and Bahamas via boats. DNA studies suggest there were at least seven different “invasions” of the lizard to Florida. This is not surprising since the lizard is small (between 5-8 inches) and likes moist areas to lay eggs. A fan of warmth, vegetation, and insects – it did very well once it arrived. Like most invasive species, it quickly spreads into disturbed areas… and we have disturbed Florida in a major way. It is now found in all counties within the Florida peninsula and in many, it is the most common lizard seen.
Is it an “invader”?
Yes, in the sense that it moves into disturbed habitats quickly and competes with the native Green Anole (Anole carolinensis). Both lizards are beneficial to humans in that they consume great numbers of insects and spiders. However, the Cuban Anole will consume the eggs and juveniles of the Green Anole. Where the two co-exist, the Green Anole is forced to live higher up in the vegetation. This is a form of resource partitioning where each species is co-existing in the same area but not directly competing. However, biologists are not sure how this co-habitation of the two lizards will affect local ecology. It is currently listed as an invasive species in Florida.
So is it new to the panhandle?
Well, based on records – yes. Based on anecdotal comments – no. Some folks have seen it for some time now. The most probable means for dispersal have been with forms of transportation visiting the panhandle from south Florida and the transport of landscaping plants from south Florida nurseries. One local nursery had a greenhouse over-run with the lizard. If you view the invasive database EDDMaps. It shows 13 records between Alabama and the Aucilla River. There are certainly more than that. EDDMaps has the distribution broken down as:
| County |
Number of Cuban Anole Records |
| Bay |
1 |
| Calhoun |
0 |
| Escambia |
0 |
| Franklin |
0 |
| Gadsden |
0 |
| Gulf |
0 |
| Holmes |
0 |
| Jackson |
1 |
| Jefferson |
0 |
| Leon |
2 |
| Liberty |
0 |
| Okaloosa |
4 |
| Santa Rosa |
4 |
| Wakulla |
0 |
| Walton |
0 |
| Washington |
1 |
Several local residents have sent me photos of the Cuban Anole in Pensacola (used in this article). I will need to post these soon and we will need help from the public posting more. To report anoles, you will need to log into EDDMaps at www.EDDMaps.org. You will need an account, but it is free. You can also download their app “I’ve Got 1”, which can be found on the website. If you have questions about EDDMaps, please contact me at the Escambia County extension office (850) 475-5230.
This Cuban Anole was photographed at the east end of Big Lagoon near NAS Pensacola.
Photo: Carole Tebay
Until then, check your cars before heading back from south Florida and any plants you may buy from nurseries to be sure you are not bringing any friends home. If you are finding them in your yard and wish to control them, contact me at the Escambia County extension office.
References
Anoles. 2017. University of Florida IFAS Gardening Solutions. http://www.gardeningsolutions.ifas.ufl.edu/design/gardening-with-wildlife/anoles.html.
Brown Anole (Anole sageri) Introduced. Savannah River Ecological Laboratory. University of Georgia. http://srelherp.uga.edu/lizards/anosag.htm.
Dunning, S. 2017. The Cuban Anole. NISAW 2017. Panhandle Outdoors Electronic Newsletter. https://nwdistrict.ifas.ufl.edu/nat/2017/02/28/nisaw-2017-cuban-anole/.
EDDMaps. 2017. Distribution Map by County. http://www.eddmaps.org/distribution/uscounty.cfm?sub=18342.
Johnson, S.A. 2011. Focal Species: Cuban Brown Anole. The Invader Updater. Vol 3 (1). http://ufwildlife.ifas.ufl.edu/InvaderUpdater/pdfs/InvaderUpdater_Winter2011.pdf.
Nonnative Species: The Brown Anole. Florida Fish and Wildlife Conservation Commission. http://myfwc.com/wildlifehabitats/nonnatives/reptiles/brown-anole/.
