When the red lionfish (Pterois volitans) first began to appear along the shores of the Florida panhandle there was a great effort to make locals aware of the potential problem. Today it is rare to find people who do not know what a lionfish is. I was recently working with a group of elementary school students in the beach classroom at the school districts environmental center. There was a tank with a lionfish in it and as I approached, they all yelled out – “that’s a lionfish”. They were all aware of this invasive species.
Red Lionfish
Photo: Florida Sea Grant
The first record of lionfish in the northern Gulf of Mexico was logged in 2010 – though a presentation at our recent panhandle lionfish workshop suggested it may have been here as early as 2008. There was immediate concern from the fishing and diving community. We began to hold workshops and local non-profits formed to begin removal tournaments. The word on the aggressive spread, fast reproductive rate, and lack of predators sent an alarm across the region.
In 2013 we held our 1st panhandle regional lionfish workshop. Researchers indicated that the densities of lionfish off our shores were the highest in the south Atlantic region – a presentation at the recent workshop indicated, at that time, the density of lionfish here may have been the highest in the world. It was not uncommon to see videos of small artificial reefs with 100 or more lionfish hanging about. It was reported that they were opportunistic feeders and had identified no fewer than 70 species of small reef fishes in their guts. The reproductive rates were an average of 30,000 fertilized eggs every four days – basically year-round. Their eggs drifted in a gelatinous sac and the spread of the fish followed the ocean currents, spreading everywhere.
War was declared.
Lionfish tournaments began to pop everywhere. They began with a few hundred or a thousand lionfish turned into events where tens of thousands of lionfish were weighed during three-day events. Lionfish education and outreach expanded across the state. Some engaged in the commercial harvest of these fish. Turned out they were quite tasty. Knowing Pensacola was sort of ground zero for lionfish density – I was contacted by chefs from around the region seeking fillets.
At the 2019 workshop researchers reported that the densities had declined in waters less than 200 feet. Everyone pointed at the recreational and commercial harvest as a possible cause, but something was obviously working. Lionfish were beginning to develop skin lesions. Scientists were not sure of the cause, and not sure whether this played a role in the density declines, but it was happening. Harvesters reported problems on the commercial side. Dive time and location were becoming problems, densities were declining – less fish to harvest, and the price point between the harvesters and the seafood industry were not where either side wanted them. One thing that seemed to be working was ecotourism. Word about huge numbers of lionfish was drawing visiting divers from all over. Dive charters were finding they could make more money but taking visitors out to shoot lionfish, than selling them to the commercial markets. There was also a supply issue. One restaurant from Charleston South Carolina contacted me asking for a source of lionfish. He said he needed about 500 pounds a week. This order would be very difficult to fill. But things from the invasive side, at least in waters less than 200 feet, seemed to be improving.
We just held the 3rd regional workshop in 2024. Researchers indicated that the densities were still down. Anecdotal reports suggest an increase in lionfish. It was thought that the pandemic reduced tournaments and commercial harvest and populations of lionfish were on the rise again. This may very well may be, but science did not show this. More studies were needed. Skin lesions are still occurring, but researchers are still not sure what is causing it. There does seem to be a link between the decline in density and the frequency of these lesions – the researchers believe that these lesions are playing at least a part in controlling their population.
One researcher reported evidence of lionfish in our estuaries. Using eDNA methods she was able to identify lionfish DNA in the upper portions of Escambia, Blackwater, Perdido, and Mobile Bays. The monitoring was done during low tide to reduce the chance of tides moving the eDNA up into the bay. She also found evidence of lionfish DNA in the feces of shorebirds nesting on our barrier islands. They are still working out how this is happening, possibly the birds are feeding on newly hatched lionfish from the drifting egg mass – not sure. But it is very interesting.
The commercial harvest is doing okay in some parts of the panhandle, but not in others. Interviewing restaurants and seafood markets we found several barriers keeping some of these businesses from providing lionfish. First was the size of the fish and percent yield of fillet. Lionfish are small and labor intensive to prepare. A second concern was the venomous spines. There were also concerns about supply and price points. However, all the seafood markets and restaurants we spoke with were interested in selling lionfish if we could overcome these barriers and were very open to the idea of education/meetings on how to do so. Florida Sea Grant does plan to begin these meetings this year.
The tournaments continue to do well. Destin’s Emerald Coast Classic is now the largest lionfish tournament in the world. Interest and participation continue to be strong. Florida Fish and Wildlife Conservation Commission’s Lionfish Challenge is also doing well, though they reported a decline in the number of commercial harvesters participating.
So as of now
Lionfish remain in the Gulf of Mexico
Densities are still low
Lesions are still occurring
Commercial harvest has not gone as well as hoped
Tournaments are doing well
Lionfish appear to be moving into the estuaries
We will see what updates the 2029 workshop will add to the story.
Each year scientists, resource managers, science educators take some time in February to make the public aware of the invasive species issue. Over the last few decades, I believe this has happened. News articles, fact sheets, public events, even kids’ television programs have covered the topic. You wonder what else needs to be said. But I have found that there is still a lot of confusion about invasive species.
For one… what exactly IS an invasive species. The term is used for almost any creature we do not like or seems to be a problem for us. And on the flip side of that, some species which have been deemed invasive we don’t see a problem with. Many have told me – “What problem does the Chinese Tallow cause? I like this tree in my yard. It is one of the few that shows color in the fall and I want to keep it”.
The Chinese tallow is an invasive species the entire state is dealing with. Photo: Rick O’Connor
There are several characteristics used to identify a creature as invasive but causing an environmental or economic problem is a big one. Many species of vine come to mind. Kudzu, Japanese Climbing Fern, and Old World Climbing fern are good examples. These plants grow rapidly, covering all things in their way – other shrubs, trees, homes, garages, electric wires, and more. You can see them expand like a cancer across the landscape and realize that all other plant life will not be able to compete with them. Then you might realize that animals that depend on those native plants are in trouble as well. And then add into the labor and cost of removing them only to watch the invasion reoccur next year. I know here on Pensacola Bay they have spent thousands of dollars trying to remove kudzu from a shoreline bank near a popular restoration area. Only to find the entire area covered again in a couple of years.
Then there are the invasive animals that have caught our eye. The Burmese python and red lionfish come to mind. Burmese pythons can reach lengths between 15-20 feet and weigh almost 200 pounds. They can consume almost any small mammal in the environment and have even taken on large ones, as well as alligators. There are thousands of them now in heavily populated south Florida and their presence is unnerving to those residents – to say the least.
The Invasive Lionfish
The red lionfish is one of the most successful invasive species ever. After the initial release(s) in southeast Florida in the 1980s they have expanded to cover the entire south Atlantic region. They are opportunistic feeders consuming whatever they can get into their mouths and altering the ecology of our coral reef systems.
But then there are comments I have heard concerning the expanded growth of native muscadine or dewberry vines across one’s yard. “These things are invasive, aren’t they?” Actually… no they are not. They may be problematic, a nuisance, but not invasive. Living in the Florida panhandle I have had residents who have moved here from south Florida ask me whether mangroves would be considered invasive here. But the spread of mangroves north is occurring naturally – so, no it would not.
So… how DO we define an invasive species?
The University of Florida IFAS Extension defines an invasive species as (1) a species not native to the area, (2) a species that was introduced by humans – whether intentional or not, (3) a species that causes either an environmental or economic problem – possibly both.
Battling invasive species can be labor intensive and costly. As you can see on the graph below, the best method is preventing the species from ever reaching your area. Easier said than done. First you need to know which species to be on the lookout for. Second you need to know how it is dispersing across the environment before you can prevent it. If you miss the initial invasion, you will see Early Detection and Rapid Response (EDRR) is the next plan of attack.
The Invasive Species Curve
Making the public aware of these species, and the problem, is what NISAW is all about. Helping the public to better understand how to manage the invasive species and prevent new ones from arriving is also a part of this effort. We will post articles about invasive species found in the Florida panhandle throughout the rest of this week. Some are in the red part of the invasive curve. Some are just beginning to be found here. If you ever have questions about a species on your property, you can always reach out to your county extension office for help and advice.
Over the course of the last week, we have been discussing invasive species issues from across the panhandle. The primary purpose was to provide information for local decision makers to develop management plans for these species. The second was to educate the local residents about which species are the largest concerns in their counties so that they too could help with management.
Cogongrass (Ray Bodrey)
Three species came up more than once: lionfish, feral hogs, and cogongrass. All three of these present large problems for the panhandle and all three are well established – party of the “dirty dozen”. In each case eradication is probably not an option. But as Ian Stone’s article from Walton County on cogongrass shows, a well thought out plan with buy in from everyone can make a difference on how bad of an impact they will have. Georgia was able to significantly reduce the impact of this grass with their comprehensive plan. The 2018 Lionfish Workshop in Ft. Walton Beach also showed that a team effort across the panhandle has helped manage that problem. Though we did not hear from Chinese Tallow, Chinese Privet, or Japanese Climbing Fern, similar efforts can go along way to reducing their impacts as well.
Cuban Treefrog
Photo: UF IFAS
We also learned about “new kids on the block” with Giant Salvinia and Cuban Treefrogs. Depending on how widespread these species are currently, eradication is possible. What it will take is an Early Detection and Rapid Response (EDRR) approach. To be successful at this local decision makers and residents will need to know:
Which species are potential threats to their counties.
How are those species transmitted.
How are they managed.
How many do you currently have in your county.
At this point the community can develop a plan to eradicate what you have and keep anymore from entering. You can find answers to these questions at your county extension office, your local CISMA website, and the EDDMapS website.
Again, with a team effort, we should be able to manage invasive species in the panhandle and reduce their impacts. As always, you can contact your county extension office for more information on invasive species issues in your area.
Ken Langeland, left, and Martha Monroe, University of Florida environmental educators, examine an invasive tallow tree on Paynes Prairie near Gainesville, Thursday 10-19. They’re part of a team of researchers from UF’s Institute of Food and Agricultural Sciences and The Nature Conservancy training people how to manage environmentally sensitive lands. With more than 11-million acres of protected land, Florida needs more trained people to help protect those environmental jewels.
It is National Invasive Species Week, a time where everyone involved in natural resources, agriculture, and related fields works to raise awareness about this issue. It is an issue that costs huge sums of money to control and address, impacts economic sectors, and requires constant inspections at ports of entry to prevent new invasives from expanding the problem. Unfortunately for us, invasive species do not recognize international borders or state and local boarders for that matter. The same is true about property boundaries, which makes controlling them on the landscape difficult. They do not politely stop at the property line. So, what are we to do about the infestation when it crosses a boundary?
In Florida there is no law that requires someone to treat or remove an invasive species from the landscape. Laws do exist that prohibit the importation of species and that prohibit propagation and planting of know invasive species. Cost share programs, grants, and other efforts exist to assist private property owners and public land managers with invasive control programs and encourage the control and eradication of invasives across Florida’s landscape. Across Florida, organizations called Cooperative Invasive Species Management Areas (CISMA’s) exist to help coordinate efforts and provide educational outreach. The CISMA that covers Walton and the surrounding counties is the Six Rivers CISMA, and this outstanding organization even crosses state boundaries to include adjoining Alabama counties. This cross-state collaboration is an outstanding example of working across boundaries to accomplish a common goal. You can learn about the Six River CISMA and it’s efforts to invasive species through their website (LOCAL PRIVATE LANDS ASSISTANCE – Six Rivers Cooperative Invasive Species Management Area (floridainvasives.org) ). Our outstanding University of Florida IFAS extension service provides research and education across the state to help inform control efforts and coordinate through a network of experts from research professionals to local county extension agents. All of these efforts are making great progress in the control and management of invasive species.
One issue still stands out as a major challenge in taking on invasives, and that is that the ability to do control stops at a property line. This is especially true for some of our worst invasives like cogongrass, Japanese climbing fern, Chinese privet, and tallow tree; just to name a few. While animals move and you can trap or remove them as they come across your property; plants stay in place and often spread in an area. If that area happens to be right along a boundary, something like a fence row, the infestation often spreads across the property line. Add to that the fact invasive species, because of the disturbance and vegetation changes, often thrive and colonize in areas like fence rows and you have a major issue. That plant doesn’t see that posted sign and the property owner must stop any treatment effort at that point. Legally a landowner cannot cross a property line, and is liable for doing so especially when mowing, burning, or spraying herbicides. Putting herbicide on a neighboring property, even if it was accidental drift, is a major no go and can land the two parties in court. At best in this situation a property owner has a good relationship with neighbors and can work something out to control the infestation. If not, the treatment must stop where the ownership stops.
Why is it a problem that a treatment stops at the property boundary? Well, cogongrass is a great example. Cogongrass is a major problem in Walton County, and across the Panhandle in general. The western panhandle and southern Alabama are considered the epicenter of this invasive, and in Walton County it is spreading like wildfire. That’s somewhat literal too as this invasive grass massively increases fire intensity and spreads. My fellow extension agent from Gulf County, Ray Bodrey, just wrote a great article about this grass and the issues it is causing. I won’t duplicate his effort and expound on how to identify it. You can see his article here NISAW: A Spreading Menace in Gulf County, known as Cogongrass | Panhandle Outdoors (ufl.edu). Needless to say, if two county agents list it as one of the top issues, then we need to focus on it.
This grass spreads rapidly and easily, especially along roadsides, right of ways, and fencerows. You might wonder why that is? Well it happens to love to hitch a ride on equipment or move in contaminated fill dirt. Add to that it is tough to kill and takes multiple years of herbicide treatment to do the trick; and you have what has been identified as the Gulf Coast’s worst invasive. In fact, it is usually listed as one of the worst invasive species worldwide. Tack all that together and throw the fact that you cannot always work across a boundary and you’ve got quite the intractable issue. And that is just our top offender, we still haven’t touched tallow tree and the other of Six River CISMA’s “Dirty Dozen”.
What can be done then if invasives are such a herculean task that requires cross boundary management? We have several options, many of which I mentioned earlier in the article. Lots of work is being done right now by everyone from private landowners to local governments and even at the federal level. Here in Walton County the local public works has an active program to report and control cogongrass in the roadway and other county right of ways. They use in house and contract teams to report, track, and treat cogongrass infestations. This is a great effort and shows a great proactivity on the part of the county government. The program will go a long way in the congongrass control effort, but it still must stop at the right of way. If the infestation goes onto private property, it is then on the private property owner to have a control plan. Without some good communication the property owner may not even realize the problem is there.
Cogongrass is a good example of why it pays for a private landowner to treat an infestation too. This grass has no forage value and chokes out any other crops, lowering agricultural yields and values. It ruins yards, turf grass, and golf courses along with dulling and damaging mowing equipment. It contaminates fill dirt and borrow pits and then spreads to areas as development and construction occurs. If you are in the fill dirt business, clients that know usually reject soil that is contaminated or could be contaminated with cogongrass rhizomes. Forest landowners suffer major impacts from this invasive grass as it makes reforestation next to impossible, increases wildfire risk, makes using prescribed fire difficult at best, reduces timber yields, and ruins the habitat value for wildlife. An unchecked cogongrass infestation can ruin land values and it will do that as it spreads across onto other property.
This loss of land value is not just conjecture either. An article published in the Journal of Agricultural and Applied Economics from research performed by scientists from the University of Florida and the University of New York found that cogongrass infestations in slash pine forests reduce the return on investment and the land value. The study (Alavalapati et al 2007) looked at the impact of cogongrass infestation on rates of return and land values in several situations: no threat of infestation, infestation uncertain with no management, infestation uncertain with treatment by one landowner, and infestation uncertain with treatment by all landowners. The study found that cogongrass negatively impacts rental rates and the land value. To assess the land value, they used a forestry measurement called the Land Expectancy Value, which is a formula that uses the expected productivity of the land, input costs, and expected timber value to determine how valuable timberland is. The study found that the land value can be decreased by up to 50% on timberland. The study also found that the annual net returns per acre are decreased by between $17.00 and $25.00 depending on the infestation and management scenarios. Those are big economic and land value impacts, and that is just for forested lands. The big finding was that the scenario that resulted in the biggest loss of land value and returns was when only one landowner was treating. Alavalapati et al 2007 found that when control measures are undertaken by all landowners in an infestation zone the impacts are lowest and the most value is preserved. They suggest that the study results show the best outcomes will be when collaborative efforts are used. While the study only looked at cogongrass, the methodology and results are applicable to other invasive species. Working across that property line has real economic benefits as well as all the ecological and landscape benefits that come from invasive species control.
Donn Shilling and Eldridge Wynn look over a research field
of cogongrass, which has become a problem for cattle ranchers.
Practical experience shows that this collaborative approach works as well. Since 2004 the Georgia Forestry Commission and the State of Georgia have implemented a cogongrass task force. Georgia recognized the severity of the issue early on, to some degree from seeing what was occurring in Florida and Alabama. They also recognized the state could not completely prevent cogongrass from entering the state but could be proactive at control and eradication. They launched a collaborative effort lead by the Georgia Forestry Commission, where landowners and others would report congongrass and the infestation would be identified and treated at no cost to the landowner. The program was structured where they could work with other landowners at an infestation site as well. The program also implemented a tracking and follow up program, which tracked the infestation until it was eradicated or became inactive. In 2007, 72 Georgia counties had detections, but as of 2021, 34 of those 72 have no active cogongrass and 85% of all known cogongrass spots in Georgia are inactive (2021-Dirty-Dozen-List.pdf (gatrees.org). That is a huge success and something that can be replicated in other states. This program took federal and state funding, state and local government involvement, coordinated tracking, and reporting and detection from landowners. It could not have happened without this collaborative effort that reached across boundaries.
Could we see something like this in Walton County or across the Panhandle? Absolutely, we could definitely build a collaborative effort on one or more invasives. Cogongrass is a great place to start, and even though it is so difficult to eradicate we have evidence that a program can be successful. What it takes is reaching across boundaries and the “Think Global, Act Local” approach, or as the Florida Invasive Species Partnership puts it “Think Locally, Act Neighborly”. Florida does not have a statewide coordinated cogongrass control effort like Georgia, but the nature of the issue in Florida is very different. Given the size and scope, a Florida eradication program would likely look much different. But why wait for a statewide program like Georgia? It would be much easier to replicate a cooperative program on invasive species at the county level. It will take working across boundaries and communicating across communities and ownerships; but we know it works. The bottom line is that inaction will result in a growing and extending problem, spreading across more and more ownerships and areas. Invasives are not just an ecological or environmental problem either, they impact land values and our economy too. The information we have shows that when control efforts are sporadic and individual; economic impacts are actually higher because landowners controlling the invasive incur costs while infestations persist in an area. To keep our land base productive and valuable we have to work together and take community efforts. This is everything from identifying and tracking infestations to control and monitoring. If it can work with cogongrass, it will work with the other major invasives as well. Most of our greatest achievements as Americans, things like making it through the Great Depression, building the Transcontinental Railroad, or winning World War II, have been through collaborative efforts. Invasive species control is going to be the same thing, and research and results on cogongrass show reaching across boundaries works. Invasives move across boundary lines; so we need to work across them to be successful. A collaborative cogongrass effort would be a great start, and then we can expand.
References and Resources
Alavalapati, J. R. R., Jose, S., Stainback, G. A., Matta, J. R., & Carter, D. R. (2007). Economics of Cogongrass Control in Slash Pine Forests. Journal of Agricultural and Applied Economics, 39(s1), 61–68. https://doi.org/10.1017/s1074070800028947
Cogongrass continues to be a thorn in the side of many landowners and municipal public works departments, as it spreads in areas across the Panhandle, with Gulf County being no exception. Thankfully, there are ways to combat cogongrass, but it seems to be an uphill battle. Identifying and being persistent with treatment are paramount in control.
Figure 1: Cogongrass infestation and uneven mid-rib in leaf blade.
Credit: Ray Bodrey, UF/IFAS Extension Gulf County.
Cogongrass (Imperata cylindrica) is found all over the world. In the U.S, it is primarily found in the southeast. Cogongrass was purposely introduced as a soil stabilizer for pasture lands in Florida during the 1930’s and 1940’s. It wasn’t long before ranchers and agricultural scientists realized that cogongrass was an invasive species. Once established, cogongrass has the ability to overrun pastures and natural areas to the point that it will be the only plant species occupant. It’s a perennial grass with a vast, ever expanding root system. This grass can grow in any soil type and low soil fertility nor drought, are concerns either. Therefore, it thrives no matter how poor the soil environment. Even with multiple days of periods of well below freezing temperatures and a prior application of herbicide, figures 1 & 2 display the resiliency of cogongrass. The major concern is the ability to eliminate native plant habitat.
Cogongrass can be confused with other grasses, like switchgrass. This is especially possible early in the year before the bloom. To identify cogongrass, first investigate the growing pattern. It usually infiltrates an area in patches. As shown in figure 1, the grass blades are flat and have a defining white mid-rib. Blades are finely serrated, yellow to green in color and are uneven in width on each side of the mid-rib. The seed head is fluffy, white and feather shaped. The seed head can alarmingly yield 3,000 seeds per head.
Figure 2: Cogongrass spreading.
Credit: Ray Bodrey, UF/IFAS Extension Gulf County.
The management strategy most successful with eradicating cogongrass consists of multiple types of herbicides sprayed over multiple year applications, with additional spot treatments. Prescribe burning can also be used in concert as an integrated approach.
For control measures, see the tables in the document referenced below. Also, contact your local county extension agent for further details.
Information for this article is from the UF/IFAS EDIS publication: “Cogongrass (Imperata cylindrica) Biology, Ecology, and
