by Rick O'Connor | Oct 31, 2015
Many coastal Panhandlers woke up this week to the sight and smell of dead fish. Thousands of them washed ashore from Panama City to Pensacola. This mass die off included a variety of species including whiting, sheepshead, hake, cusk eels, and even lionfish; there were also reports of dead bass from the Dune Lakes in Walton and Okaloosa counties. What caused this mass die off of fish?
The suspect is red tide…
Most of us along the panhandle have heard of red tide but we may not know what it is or what causes it. Many attribute the red tide events to human impacts, stormwater runoff etc., but in fact they have been around for centuries. There are records suggesting that the European colonials experienced them and I have read one account that the Red Sea got its name from the frequency of these events there. So what is this “red tide” and what causes it?
Dead fish line the beaches of Panama City.
Photo: Randy Robinson
It is actually a bloom of small single celled plants called dinoflagellates. There are thousands of species of dinoflagellates in the world’s oceans and not all cause red tide, but there are several species that do. These small microscopic plants drift near the surface of the ocean acquiring sunlight to photosynthesize. They possess two small “hairs” called flagella (hence the name “dinoflagellate”) to help orient themselves in the water column. Most have a shell covering their body called a theca and some shells have small spines to increase their surface area to resist sinking. One method of defense found in some dinoflagellates is the production of light – bioluminescence. This light is produced by a chemical reaction triggered by the creature as a flash of blue – many locals refer to it as “phosphorus”. Other dinoflagellates instead will release a toxin… some of these are ones we call “red tide”.
Red tide organisms are always in the water column of marine environments but are usually in low concentrations, maybe 300-500 cells per milliliter of water. But under favorable conditions, warm water with nutrients, they multiple… sometimes in great numbers, such as 3000-5000 cells/ml, and we have a “bloom”. The number of cells within these blooms can be high enough that we can actually see the water change color… hence “red tide”.
The dinoflagellate Karenia brevis.
Photo: Smithsonian Marine Station-Ft. Pierce FL
The most common red tide dinoflagellate associated with the Gulf of Mexico is Karenia brevis. Karenia blooms typically form offshore and are of little impact to the coastal communities. However when the wind and tides are right these blooms will drift towards shore. When they do fish kills occur and humans have eye and throat irritations. Marine mammals in particular struggle with red tide. As the bloom comes near shore it reaches the bottom of the water column and many of the bottom dwelling fish suffer. Most of the photos of fish I saw in the October 2015 fish kill were bottom dwellers, including many invasive lionfish.
Is there anything we can do to prevent red tides?
Not really… Again, they are naturally occurring event. We may increase the frequency of the events by discharging excessive nutrients into the water from our run-off but they would probably occur anyway. Red tide events are not as common in the panhandle as they are in southwest Florida. The Gulf waters near Charlotte Harbor are shallow, warm, and near the many manicured lawns, gold courses, and the discharge of much of the agriculture in the state. Occasionally blooms formed in that part of the state drift north but this year a bloom formed off of Bay and Gulf counties in early October. The recent storm that passed through probably pushed the bloom inland and to the west. The biggest hazard of humans is eye, throat, and skin irritation. It is quite uncomfortable to be around these blooms. In 1996 a local bloom was concentrated enough that the campground at Ft. Pickens had to be closed. I was in Galveston Texas when I heard about the red tide occurring in the Florida panhandle. As I was leaving Galveston the newspaper reported the closer of all oyster harvesting in Texas due to a red tide generated in the Padre Island area and was moving north. Seems that red tide is covering a large portion of the Gulf coast the last week of October. That said… anything communities can do to reduce nutrient runoff will certain decrease the frequency of red tides.
The carcass of the invasive lionfish was part of the October red tide kill.
Photo: Shelly Marshall
The Florida Fish and Wildlife Conservation Commission post red tide updates from around the state on their website and the Escambia County Extension Office post a local water quality update each Friday that has red tide information as well.
FWC
http://myfwc.com/research/redtide/
Escambia County Extension
http://escambia.ifas.ufl.edu
by Rick O'Connor | Sep 24, 2015
The red area indicates where dissolved oxygen levels are low.
I don’t want this to sound like a “Debbie Downer”… but there are problems with our estuaries and panhandle residents should be aware of them. There are things you can do to correct them – which we will discuss in the final issues of this series – but you need to understand the problem to be able to solve it. Unfortunately there are many issues and problems our bays and bayous face and we do not have time in this short article to discuss them all, but we will discuss some.
We’ll start at the top… with our rivers. Since the founding of our nation many communities were built on estuaries; those that were not were built on the rivers. Water was an easy way to move throughout the country – much easier than wagon crossing over the Appalachians or through a bog. There are several communities that developed along the rivers that feed the panhandle bays. Though the situation has improved in the last few decades, most of these communities have used these rivers as a place to dump their waste. Assorted chemicals, sewage, and solid waste were discharged… and it all came down to us. The Mississippi River is an example of this problem. Discovered in the 1990’s the Louisiana Dead Zone is an area in the Gulf where the levels of dissolved oxygen are so low that little or no life can be found on the ocean floor there. It is believed to be trigger by nutrients, chemical fertilizers and animal waste, being discharged upstream. These nutrients create a bloom of plankton, which can darken the water. Though the phytoplankton can produce oxygen during the daylight hours, they consume it in the evening, lowering the concentration of dissolved oxygen within the water column. The plankton are relatively short lived and eventually die. As the dead plankton fall out to the seafloor bacteria begin to decompose their bodies thus dropping the dissolved oxygen levels further. When the dissolved oxygen concentrations drop below 4.0 millgrams/liter we say the water is hypoxic (low in oxygen). Many species of aquatic organisms begin to stress. At 2.0 mg/L many species will die and we have a “dead zone”. If it reaches 0.0 mg/L we say the water is anoxic (without oxygen). This process is called eutrophication and not only a problem at the mouth of the Mississippi River, it occurs in almost all of the bays and bayous of the panhandle and is the primary cause of local fish kills.
A more recent issue with our rivers has been the reduction of water. In the so called “Water Wars” the state of Georgia has used its damn system to block the flow of the Chattahoochee River to create electricity and a reservoir of drinking water for river communities. Under normal conditions this has not created a problem however in recent years the southeast has experienced drought and the state of Georgia has had the need to hold back water for large communities – such as Atlanta. This has reduced the amount of water flowing towards the Gulf and has impacted communities all along the way. It is not the only issue but is the primary factor triggering the collapse of the oyster industry in Apalachicola. The reduced freshwater flow has increased salinities in the bay. This has disrupted the life cycle of the eastern oyster and has increased both predation and disease within these populations. Apalachicola produces over 90% of Florida’s oysters and 10% of the oysters for the entire country! Oysters are a huge industry in this town. Many are oystermen and many others process the product when it is landed… the industry is on the verge of collapsing. (Learn more).
Oysterman on Apalachicola Bay.
Photo: Sea Grant
These are just some the issues stemming from the rivers… what about the issues initiated from the communities that live along the bay…
How about the seafood? We discussed the oyster industry in Apalachicola Bay but oyster production in other local bays has declined as well (for other reasons). Scallops are gone from many of their historic estuaries, shrimp and blue crab landings are down, this year mullet seem to be hard to find. What is going on here? For the most part the decline in seafood products can be tied to either a decline in water quality or from over harvesting. The harvesting issue is easy… do not harvest as much. However these fisheries management decisions impact many lives and has caused a lot of debate. First you need to determine whether the decline is due to overharvesting or some other environmental factor… easier said than done. Certainly the biology of your target species will give you an idea of how many animals you can remove from the system and sustain a healthy population (maximum sustainable yield) but this method has triggered debate as well. Most fishermen do not want to see the fishery collapse and are willing to work with fishery managers to assure this – but they do have bills to pay. Fishery managers have a responsibility to assure the fishery remain for current and future generations of fishermen and they are basing their decisions on the best available science. It is a touchy subject for many and a problem within our estuaries.
The other cause of declining seafood is poor water quality. You can talk to any “ole timer” and they will tell you about the days when the water was clearer, the grass was thicker, and the fish were more abundant… what happen? I spoke with my father-in-law before he passed away about the changes he saw in Bayou Texar in Pensacola. He remembers being able to see the bottom, more seagrass, and being able to catch a variety of finfish as well as shrimp the size of your hand. The first change he remembered was a change in water clarity… it became murkier… and this happen about the time they began to develop the east side of the bayou. As our communities grew more land was cleared for development. The cleared land allowed more runoff to reach the creeks, bayous, and bays. Infrastructure had to be placed to reduce flooding of yards and streets – Bayou Texar has 38 storm drains. All of this led to more runoff into our water ways. With the increase in turbidity the amount of sunlight reaching the bottom was reduced and seagrasses began to decline. Many species of seagrass require salinities of 25 parts per thousand or higher and the increase in freshwater runoff lowered the salinity which also stressed these grasses. Much of this runoff included sand and silt and the grasses were basically buried. All in all seagrasses declined… and with them many of the marine creatures. Salt marshes were removed for coastal developments, industries were located on our rivers and bays and introduced their chemical discharge, and boating activity increased… our estuaries were being literally “loved to death”. I have seen in my lifetime the decline of sea urchins and scallops from our bay, the increase in turbidity, and the decline of seagrasses. But we cannot blame all of this on habitat loss and pollution. Speaking recently with fisheries managers they believe the recent decline in blue crab landings is due to drought. Reduction in rainfall means reduction in river discharge, which means an increase in salinity and a disruption of the crab reproductive cycle.
Power plant on one of the panhandle estuaries.
Photo: Flickr
Another problem that is associated with runoff has been the increase in bacteria. Fecal coliform bacteria are found in the stomachs of birds and mammals. They assist with our digestion and are released into the environment whenever we (or they) go to the bathroom. So finding fecal coliforms in the water is not unusual… the problem is TOO many fecal coliforms. As mentioned coliforms are not a threat to us but they are used as an indicator of how much waste is in the water. Feces harbors many other microbes in addition to coliforms – hepatitis and cholera outbreaks have been linked to sewage in the water. So agencies monitor for these each week. Most agencies will monitor for E. coli when sampling freshwater and Enterococcus in saline waters. E. coli values of 800 colonies / 100 milliters of sample or higher, and Enterococcus values of 104 colonies / 100 ml of sample will trigger a health advisory being issued – and some bodies of water being closed. In the Pensacola area the Florida Department of Environmental Protection and the Escambia County Health Department both monitor for bacteria. They post their results each week and I, in turn, post to the community. Our local bayous are averaging between 8-10 advisories each year. The problem with these advisories is that residents who live on the waterways, businesses (such as hotels and ecotours) who use the waterways become concerned about entering the water. It is not good for business or property values if the body of water you are on has high levels of bacteria and signs posting “no swimming”.
Closed due to bacteria.
Photo: Rick O’Connor
There are many problems our estuaries are facing but for this article we will end with solid waste. Trash and garbage has been a problem since I can remember. Campaigns have been launched each decade to try and reduce the problem but the problem still exist. Plastics and monofilament litter the beaches and waterways creating problems for marine life and an “eye soar” for those enjoying the bay. I am currently working with the Wildlife Sanctuary of Northwest Florida and CleanPeace to monitor solid waste in Pensacola Bay. Each week CleanPeace host a Saturday event they call “Ocean Hour” where they select a location on the bay and clean for an hour. They submit the top three items to me each week and have been doing this since January… it has been pretty consistent… cigarette butts, plastic food wrappers, and plastic drink containers. We are not going to get rid of garbage on our beaches but if we can consistently reduce the “top three” we should be able to reduce the problem.
More on what we can do to help in the final issue.
by Rick O'Connor | Jul 10, 2015
What is the Gulf of Mexico Dead Zone you ask? Well…it’s a layer of hypoxic water (low in dissolved oxygen) on the bottom of the Gulf of Mexico. It was first detected in the 1970’s but reached its peak in size in the 1990’s. The low levels of dissolved oxygen decrease the amount of marine life on the bottom of the Gulf within this zone, including many commercially valuable species supporting the Gulf seafood industry.
The red area indicates where dissolved oxygen levels are low.
What Causes this Dead Zone?
Drops in concentrations of dissolved oxygen within the water column can occur for a variety of reasons but is usually caused by one of two reasons. (1) Increasing water temperatures—as water temperature increases, its ability to hold dissolved oxygen decreases. (2) A process called eutrophication.
What is eutrophication?
Eutrophication is a process where an increase of nutrients in an aquatic system triggers an algal bloom of microscopic phytoplankton. These phytoplankton produce oxygen during the daylight hours but consume it in the evening. Once the bloom dies, decomposing bacteria begin to break them down and consume larger amounts of dissolved oxygen in doing so. When the dissolved oxygen concentrations drop below 2.0 mg/L we say the water is hypoxic and many marine organisms either begin to move out or die. The nutrients that trigger such blooms are primarily nitrates and phosphates. These can be introduced to the water column with plant and animal waste and with synthetically produced fertilizers we use on our fields and lawns. There is natural eutrophication, but when the process is triggered or accelerated by human activity we use the term cultural eutrophication.
So which is it; warming waters or eutrophication?
The Gulf of Mexico Dead Zone usually forms in spring and lasts through September. These are certainly the warmer months of the year, but the warmer waters are near the surface and much of the water column is not warm enough to cause this. Another point is that the Dead Zone is near Louisiana and there are warm locations in other parts of the Gulf where dead zones do not occur. However the Mississippi River does discharge near Louisiana. This river drains 41% of the continental United States, which contains 52% of the nation’s farms. The agricultural waste (plant, animal, and synthetic fertilizers) discharged into the Mississippi River contains nitrogen and phosphorus, the two key nutrients that trigger algal blooms. Based on this, most scientists agree that cultural eutrophication is the primary cause of the Gulf Dead Zone.
When they say it will be a “typical year”, what does that mean – what is a “typical year”?
Scientists from NOAA, the U.S. Geological Survey, and six partnering universities have released their annual forecast of the Dead Zone. The 2015 prediction has the area of the dead zone about equal to the size of Connecticut, which has been the average size for the past several years. This is what they mean by typical.
Can these dead zones occur in our area waters?
Yes, and they do. We do not typically call them “dead zones” but the same process occurs all over the world, including the bays of the Florida panhandle.
What can we do to reduce cultural eutrophication locally?
If you can do without fertilizing your lawn (or field), then do. If this is not an option then only put the amount of fertilizer required for your land/lawn. Most people over fertilize, which not only reduces water quality but is expensive for the property owners. If you can compost your plant waste, do so. With animal waste, please dispose of properly, in a manner where it not reach local waterways.
For more information on hypoxia, eutrophication, and solutions to reduce this problem, contact your county Extension office.
http://www.tulane.edu/~bfleury/envirobio/enviroweb/DeadZone.htm
http://www.iseca.eu/en/science-for-all/what-is-eutrophication
http://earthobservatory.nasa.gov/Features/Phytoplankton/
by Rick O'Connor | Jul 10, 2015
After the recent report of a fatality due to the Vibrio bacteria near Tampa many locals have become concerned about their safety when entering the Gulf of Mexico this time of year. So what are the risks and how do you protect yourself?
The rod-shaped bacterium known as Vibrio. Courtesy: Florida International University
What is the Flesh Eating Disease Vibrio?
Vibrio vulnificus is a salt-loving rod-shaped bacteria that is common in brackish waters. As with many bacteria, their numbers increase with increasing temperatures. Though the organism can be found year round they tend peak in July and August and remain elevated until temperature decline.
How do people contract Vibrio?
The most common methods of contact with Vibrio are entrance through open wounds exposed to seawater or marine animals and by consuming raw or undercooked shellfish, primarily oysters. The bacterium can also be contracted by eating food that is either served, and has made contact with, raw or undercooked shellfish or the juice of raw or undercooked shellfish.
What is the risk of serious health problems after contracting Vibrio?
Cases of Vibrio infection are rare and the risk of serious health problems is much higher for humans who are have a suppressed or compromised immune system, liver disease or blood disorders such as iron overload (hemochromatosis). Examples include HIV positive, in the process of cancer treatment, and studies show a particularly high risk for those with a chronic liver disease. The Center for Disease Control indicates that humans who are immunocompromised have an 80 times higher chance of serious health issues from Vibrio than healthy people. He also found that most cases involve males over the age of 40. According to the Center for Disease Control there were about 900 cases reported between 1988 and 2006; averaging around 50 cases each year. The Florida Department of Health reported 32 cases of Vibrio infections within Florida in 2014 with 7 of these begin fatal. Five of the cases were in the Florida panhandle but none were fatal. So far this year in Florida there have been 11 cases statewide, 5 of those fatal. Only 1 case was in the panhandle and it was nonfatal. Though 43 cases and 12 fatalities over the last two years in Florida are reasons for concern, when compared to the number of humans who enter marine and brackish water systems every day across the state, the numbers are quite low.
What are the symptoms of Vibrio infection?
For healthy people who consume Vibrio containing shellfish symptoms could include vomiting, diarrhea, and abdominal pain. Wounds exposed to seawater that become infected will show redness and swelling. For the at-risk populations described above the bacteria will enter the bloodstream and rapidly cause fever and chills, decreased blood pressure, and blistering skin lesions. For these at-risk population 50% of the cases are fatal and death generally occurs within 48 hours.
It is important that anyone who believes they are at high risk and have the above symptoms that they seek medical attention as quickly as possible.
How can I protect myself from Vibrio infection?
We recommend anyone who has a chronic liver condition, hemochromatosis, or any other immune suppressing medical condition, not consume raw or undercooked filter-feeding shellfish and not enter the water if they have an open wound.
The Center of Disease Control recommends
- If harvesting or purchasing uncooked shellfish do not consume any whose shells are already open
- Keep all shellfish on ice and drain melted ice
- If steaming, do so until the shell opens and then for 9 more minutes
- If frying, do so for 10 minutes at 375°F
- Avoid foods served, and has had contact with, raw or poorly cooked shellfish or that has had contact with raw shellfish juice
- If shucking oysters at a fish house or restaurant, wear protective gloves
It is also important to know that the bacteria does NOT change the appearance or odor of the shellfish product, so you cannot tell by looking at them whether they are good or bad.
For more information on this bacteria visit:
http://www.floridahealth.gov/diseases-and-conditions/vibrio-infections/vibrio-vulnificus/
http://www.cdc.gov/vibrio/vibriov.html
by Rick O'Connor | May 15, 2015
Following a previous article on the number of ways you can help sea turtles, this week we will look at ways that local residents can help keep our waterways clean. Poor water quality is a concern all over the country, and so it is locally as well. When we have heavy rain all sorts of products wash off into streams, rivers, bays, and bayous. The amount and impact of these products vary but most environmental scientists will agree that one of biggest problems is excessive nutrients.
Marine science students monitoring nutrient levels in a local waterway. Photo: Ed Bauer
Nutrient runoff comes in many forms. Most think of fertilizers we use on our lawns but it also includes grass clippings, leaf litter, and animal waste. These organic products contain nitrogen and phosphorus which, in excess, can trigger algal blooms in the bay. These algal blooms could contain toxic forms of microscopic plants that cause red tide but more often they are nontoxic and cause the water to become turbid (murky) which can reduce sunlight reaching the bottom, stressing seagrasses. When these algal blooms eventually die they are consumed by bacteria which require oxygen to complete the process. This can cause the dissolved oxygen concentrations to drop low enough to trigger fish kills. This process is called eutrophication. In addition to this, animal waste from birds and mammals contain fecal coliform bacteria. These bacteria are used as indicators of animal waste levels and can be high enough to require health advisories to be issued.
So what we can do about this?
- We can start with landscaping with native plants to your area. Our barrier islands are xeric environments (desert-like). Most of our native plants can tolerate low levels of rain and high levels of salt spray. If used in your yard they will require less watering and fertilizing, which saves the homeowner money. It also reduces the amount of fertilizer that can reach the bay.
- If you choose to use nonnative plants you should have your soil tested to determine which fertilizer, and how much, should be applied. You can have your soil tested at your county Extension Office for a small fee. Knowing your soil composition will ensure that the correct fertilizer, and the correct amount, will be used. Again, this reduces the amount reaching the bay and saving the home owner money.
- Where ever water is discharged into the bay you can plant what is called a Living Shoreline. A Living Shoreline is a buffer of native marsh grasses that can consume the nutrients before they reach the bay and also reducing the amount of sediment that washes off as well, reducing the turbidity problem many of our seagrasses are facing.
These three practices will help reduce nutrient runoff. In addition to lowering the nutrient level in the bays it will also reduce the amount of freshwater that enters. Decrease salinity and increase turbidity may be the cause of the decline of several species once common here; such as scallops and horseshoe crabs. Florida Sea Grant is currently working with local volunteers to monitor terrapins, horseshoe crabs, and scallops in Escambia and Santa Rosa counties. We are also posting weekly water quality data on our website every weekend. You can find each week’s numbers at http://escambia.ifas.ufl.edu. If you have any questions about soil testing, landscaping, living shorelines, or wildlife monitoring contact Rick O’Connor at roc1@ufl.edu. Help us improve water quality in our local waters.
