NISAW 2024 – Beach Vitex

NISAW 2024 – Beach Vitex

National Invasive Species Awareness Week

ARE YOU AWARE OF THE INVASIVE DUNE PLANT CALLED BEACH VITEX?

I would say most are not.  Though the plant was known over a decade ago, the education/outreach on this species has not been equal to the effort of lionfish. 

Vitex beginning to take over bike path on Pensacola Beach. Photo credit: Rick O’Connor

In 2012 I was contacted by a Gulf Breeze resident who had the invasive vine – beach vitex (Vitex rotundifolia) growing on her property.  They told me that had it under control but felt it was coming from Pensacola Beach.  I checked the EDDMapS database and found only three records of the plant in the state of Florida.  Two were in Jacksonville and one was on Pensacola Beach.  So, I went to investigate. 

It was there… and it was pretty bad.  The front yard was about 25% covered with the plant but a side yard and the back yard were 100% covered.  I surveyed other parts of Pensacola Beach and found the plant in other locations.  If you remember from Part 1 of this series, if you cannot prevent the invasive species from reaching your location, the next thing is Early Detection Rapid Response (EDRR).  This was definitely an EDRR species.  We needed to get on top of this as soon as possible. 

In 2013 I conducted a survey of Pensacola Beach on my bicycle.  I found eight more locations that had the plant.  They were all on private property.  I asked the homeowners if they knew how the plant got there.  Some replied that they had planted it.  Others said that they had hired a landscaper, and this was the plant they had chosen.  Others had no idea where it came from.  At the time, beach vitex was not listed as an invasive species in Florida.  It is now and is also listed as a Florida noxious weed (you can no longer sell it).  It was time for a Rapid Response – education about the plant, its invasiveness, and how to manage. 

Beach vitex is native to the Pacific coast of Asia.  There, it grows in coastal areas where there is plenty of open sunlight and well drained soils.  It was brought to the U.S. as a possible ornamental plant in the 1950s.  There are no records of what happened to those initial plants, but a second wave was brought to North Carolina in the 1980s.  They decided to use the plant in dune restoration after a hurricane and that is when it “raised its ugly head”.

Beach vitex is allelopathic – it releases compounds that pull water away from the native plants causing their death – vitex then takes over the newly empty space – spreading across the beach.  The plant has a taproot from which extend vines that run across the surface of the sand in almost a 360° pattern.  It begins as a soft herbaceous vine, but with time, becomes woody and larger in diameter.  It will eventually grow vertical and become more of a shrub.  In the Carolina’s it took over the dune systems forming a thick monoculture resembling kudzu – giving it their local name “beach kudzu”.  During the summer months the vines can grow very quickly – up to 20 feet in one week – covering the landscape.  At the time they were concerned this would impact sea turtle nesting, now there is evidence that it has.  It also impacted a state listed dune plant they were trying to protect.  North and South Carolina formed a state task force to battle the plant and have spent hundreds of thousands of dollars doing so.  When we first posted we had found it on Pensacola Beach I was contacted by the Carolina Task Force and advised to get rid of it as quickly as possible. 

My most recent survey was conducted in the fall of 2023.  Currently the plant has been found at 100 sites. 

  • 61 of these are on Pensacola Beach.  57 (93%) are east of Casino Beach and 32 of those (56%) are north of Via DeLuna Blvd. 
  • 25 are within Gulf Islands National Seashore and 24 of those are at Naval Live Oaks.
  • 7 sites at Navarre with 6 of those on Navarre Beach.
  • 3 sites are in Gulf Breeze proper. 
  • 2 sites are on Perdido Bay.
  • 2 sites are on Perdido Key.

At this time 74 of the 100 sites have been treated or removed. 

36 of those 74 sites (49%) the plant has not returned.  Treatment continues on the other 38 sites. 

39 of the 61 sites on Pensacola Beach are private property, and it is up to the homeowner to manage the plant.  Florida Sea Grant continues to hold community events to manage the 9 public sites on Pensacola Beach. 

The most recent EDDMapS database shows that beach vitex occurs in two other panhandle counties.  These include Okaloosa and Franklin.  It is very possible they occur in others, but surveys have not been conducted. 

Methods of managing this plant vary.  Small, individual plants can be successfully removed by hand with no regrowth.  Small patches can be removed to the taproots and those can be spot sprayed with herbicide.  Large patches are very difficult to remove by hand and herbicides are recommended. 

If you have questions as to whether or not you have beach vitex in your area, or need advice on how to manage it, contact your county extension office.  It is EDRR time. 

NISAW 2024 – Red Lionfish

NISAW 2024 – Red Lionfish

National Invasive Species Awareness Week

ARE YOU AWARE OF THE RED LIONFISH?

Yes… I would say most of you are.

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.

NISAW 2024 – Introduction

NISAW 2024 – Introduction

National Invasive Species Awareness Week

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. 

Winter Wildlife Part 2 – Bald Eagles

Winter Wildlife Part 2 – Bald Eagles

Six months ago, they were predicting a colder than normal winter.  In January that seemed to be the case.  We had multiple fronts with high winds and temperatures dropping into the 20s.  But February has been different.  As I type this, it is 62°F and we have had some of the nicest days we have had in a while.  Sunny, low humidity, really nice.  AND THE GROUNDHOG SAW HIS SHADOW!!! So… maybe an early spring? 

With the warmer temperatures I thought we might encounter some of our ectothermic friends (amphibians and reptiles).  On days like we have seen, snakes and turtles will come out from their winter hiding spots to bask in the sun.  Since our early winter article, two cottonmouths have been seen on Santa Rosa Island.  They were both reported as being very sluggish – but that is to be expected – it is still winter, and the temperatures are still low in the mornings.  With that thought in mind we did our February mid-winter hike at Ft. Pickens. 

A cottonmouth found on the trail near Ft. Pickens. Photo: Ricky Stackhouse

The hike was on February 6.  It was a beautiful sunny day, the temperature was 49°F, light wind from the north.  I will say, in the wind it was a bit chilly, but behind the dunes it was very pleasant. 

Along the trail I noticed a lot of green plants, but nothing was in bloom.  Often the change in temperature can fool flowering plants into blooming early.  However, the pine trees were full of male and female cones.  They were definitely getting ready for pollen season. 

The female cone of a pine tree. Photo: Rick O’Connor
The male cones of this pine tree are releasing the all too familiar yellow dust pollen. Photo: Rick O’Connor

I began in the middle of the island in the hardwoods, moving slowly hoping to find a basking snake.  I did not, but I did see numerous woodland songbirds.  I am not a good birder, but I believe there were varieties of warblers, titmice, wrens, and the always present mockingbird.  I did spot a great blue heron on a nest.  Birds are endothermic – and this is their time – a great time to do some birding if you like that. 

Blue herons often use the tops of pine trees for nesting. Photo: Rick O’Connor

I took another trail heading towards the beach.  This crossed through more woodlands before reaching the dunes and the shore.  It was in the woodland area I came across a bald eagle nest.  Many of us remember a time when we never saw bald eagles around here.  Now they are becoming more common and nesting all around the bay area.  These awesome birds are similar to dolphins, sea turtles, manatees, and the Blue Angels – you never get tired of seeing them.  It is always an exciting moment when one flies over.  

The American bald eagle. Photo: Rick O’Connor

There was no wildlife on the beach that day but there were plenty of tracks.  Mammals, even in the winter, still prefer to move around under the cover of darkness.  I found the tracks of armadillo and raccoon, common mammals on our island, but there was another set that was harder to identify.  The paw had the imprint of a cat (no claws visible) but the track was quite large for a feral cat.  If it was, it was a big cat.  I have seen bobcats in the Gulf Breeze area, and you cannot rule them out, but the pattern of the stride appeared more like an otter.  Otter tracks would be webbed – these were not – so… I am not sure what it was.

Most encounter island mammals by finding their tracks. Photo: Rick O’Connor

Leaving the beach, I returned to the inland trail heading back to the truck.  On this portion of the trail, you cross over ponds just outside the walls of the fort.  As I glanced across the water – hoping for a swimming snake – I saw something else.  It surfaced briefly and then dove again.  At first, I thought it was a diving bird, such as a cormorant or loon, but when it resurfaced, I saw that it was not.  It was an otter.  I had seen otters before in this area, and other pond areas on the island, but – like the bald eagle and dolphin – it is always exciting to see them again. 

Based on this hike, it is still the time of the “warm-blooded”.  Birds and mammals were the creatures most visible.  We will see if this warming trend continues.  Maybe during the late winter hike in March, we will see some of the “cold-bloods” come out.  Maybe it WILL be an early spring. 

Get out and hike – the weather is fine! 

Tagging Wildlife Part 2 – Leatherback Sea Turtles

Tagging Wildlife Part 2 – Leatherback Sea Turtles

The leatherback sea turtle is the largest of the five species that have been found in the northern Gulf of Mexico.  With a carapace (top shell) length between 6-7 feet and weighing between 800-1000 pounds it is truly a magnificent creature.  Any encounter with them is amazing. 

Most encounters occur with fishermen or divers who are out searching for artificial reefs to fish or dive.  Though very rare, they have been known to nest in this area.  They feed exclusively on jellyfish and will follow them close to shore if need be.  But what do leatherbacks do with most of their time?  Do they hang offshore and follow jellyfish in?  Do they circle the entire Gulf of Mexico and we see them as they pass?  Based on past studies, many encounters with this turtle occur in the warmer months.  They often become entangled in commercial fishing longlines set in the central Gulf of Mexico.  But what do they do during the fall and winter?  One of the tagging projects presented at a recent workshop tried to answer that question. 

The project was led by Dr. Christopher Sasso of the National Oceanic and Atmospheric Administration.  The tag chosen for this was a satellite tag.  Since the leatherback must surface to breath air, and often is found near the surface following jellyfish, orbiting satellites would be able to follow them.  As we mentioned in Part 1, catching the creature is step 1, and catching a six-foot 1000-pound sea turtle is no easy task. 

The team used a spotter aircraft to locate the turtles.  Once found, the pilot would radio the chase boat who would zip in with a large net.  The net was connected to a large metal hoop and was designed to give way once it was around the turtle.  Once in the net the turtle was hauled onto a small inflatable boat where the work of tagging could be done.  They would measure the animal, take blood samples, place a PIT tag within them (similar to a microchip in your pet) and then attach the satellite tag by a tether to the tail end of the turtle before releasing it.  The entire operation took less than 30 minutes.    

Between 2015-2019 19 leatherbacks were tagged in the northern Gulf.  17 of these were females and 2 were males.  Data obtained from these tags ranged between 63 and 247 days at liberty.  The behavior the team noticed was divided into foraging behavior (feeding on jellyfish) and transiting behavior (direct swimming ignoring all). 

The turtles foraged in this part of the Gulf until the fall season.  At that point most of them moved south along the Florida shelf, past the western peninsula of the state, heading towards the Keys.  A few chose to swim directly south against the Loop Current, and a small number remained in the area. 

Those moving along the Florida shelf appeared to be foraging as they went.  Those crossing the open Gulf may have foraged some but seemed to be focused on getting south to the nesting beaches.  Almost all of the turtles entered the Caribbean on the east side of the Yucatan channel, following the currents, with their final destination being their nesting beaches.  When they returned, they did so in the warmer months and used the western side of the channel – again following the currents – until they once again reached the northern Gulf and foraging began again.  One interesting note from this study, the two males tagged did not leave the Gulf.

The tagging studies do show that leatherbacks use the Gulf of Mexico year-round.  They usually head south to the Caribbean when it gets colder and use the currents to do so.  It is during the warmer months we are most likely to see them here foraging on jellyfish.  It is an amazing experience to encounter one of these large turtles.  I hope you get to experience it one day.

Satellite tracks of leatherback movement in the GoM. Red (2015), Blue (2018), Black (2019). Image: Sasso (et.al.) 2021.

Reference

Sasso, C.R., Richards, P.M., Benson, S.R., Judge, M., Putman, N.F., Snodgrass, D., Stacy, B.A. 2021. Leatherback Sea Turtles in the Eastern Gulf of Mexico: Foraging and Migration Behavior During the Autumn and Winter. Frontiers in Marine Science., Vol. 8., https://doi.org/10.3389/fmars.2021.660798.