by Rick O'Connor | Aug 3, 2018
Of all the issues facing our local estuaries, high levels of fecal bacteria is the one that hinders commercial and recreational use the most. When bacteria levels increase and health advisories are issued, people become leery of swimming, paddling, or consuming seafood from these waterways.
Closed due to bacteria.
Photo: Rick O’Connor
I have been following the fecal bacteria situation in the Pensacola Bay system for several decades. Cheryl Bunch (Florida Department of Environmental Protection) has done an excellent job monitoring and reporting the bacteria levels, along with other parameters, for years – she has been fantastic.
The organisms used for monitoring have changed, so comparing numbers now and 30 years ago is somewhat difficult – but those changes came with good reason.
Fecal bacteria are organisms found in the large intestine of birds and mammals. They assist with digestion and are not a real threat to our health. Understanding that both birds and mammals in and near our estuaries must defecate, it is understandable that some levels of these bacteria are in the waterways. However, when levels are high there is a concern there are high levels of waste in the water. This waste can carry other organisms that can cause health problems for humans – such as hepatitis and cholera. So fecal bacteria monitoring is used as a proxy for other potential harmful organisms. No one wants to swim in sewage.
E. coli is a classic proxy for this type of monitoring and has been used for years. Recently it was found that saline water could kill some of the fecal bacteria – giving monitors’ low readings in estuarine systems – suggesting that there is little sewage in the water – when in fact there may be high levels of sewage undetected. They have found Enterococcus a better proxy for marine waters, particularly Enterococcus faecalis. Researchers have determined that a single sample of bay water should have more than 35 colonies of Enterococcus (ENT). If they find 35 or more colonies – a second sample is taken. If the counts are again high – a health advisory will be issued.
Over the last 30 years of monitoring FDEP’s reports on the Pensacola Bay area – there have been patterns. Most of the “hot spots” have been bayous and locations where rivers are discharging into an estuary. In addition, the periods of high fecal counts correspond well with periods of high rainfall. Locally, in the Pensacola Bay area, sampling has been reduced due to budget issues and some bodies of water are not sampled as often as others. Today both FDEP and the Florida Department of Health (FDOH) monitor and post their data via the Healthy Beaches Program. In this program, the sample stations are commonly used swimming areas – meaning some other locations are rarely, if ever, sampled. Based on these data, 30-40% of the samples from local bayous annually require a health advisory to be issued.
Health advisories can reduce interest in human related recreation activities, such as wakeboarding, paddling, or even fishing – and certainly impacts interest in swimming. Decades ago, swimming and skiing were very popular in local bayous. Today it is rare to see anyone doing so – most are motoring through heading to open bodies of water to spend their day. It may also be effecting property purchases. I have been contacted more than once with the question “would you buy on a house on XXX Bayou?”
Several local waterways are listed as impaired, and one is a BMAP area, due to high levels of bacteria. A BMAP (Basin Management Action Plan – read more at the link below) is a state designated body of water that is impaired (for some reason) and is required to make annual improvements to reduce the problem.
The spherical cells of the “coccus” bacteria Enterococcus.
Photo: National Institute of Health
So What Can We Do to Reduce This Problem?
In the Pensacola area, both the city and county have made efforts to modify and improve stormwater problems. Baffle boxes in east Pensacola have helped to reduce the amount of runoff entering the bayous and bays, thus reducing the frequency health advisories are being issued. That said, during heavy events the counts still increase – and rainfall seems to be increasing in the area in recent years. We will continue to monitor the frequency of advisories and post these on Sea Grant Notes through the Escambia County extension office each week.
From our side of the story (you and me) – anything you can do to reduce runoff will certainly help. Florida Friendly Landscaping techniques are a good start (see article on FFL posted below). Clean up after your pet, both in your yard and after walks – most people do… but not all. Septic systems have been a point of concern. If you have a septic system, maintain it (see article below on how). If the opportunity presents itself, you can move from septic to a sewer system. At many public places along the waterfront have signs asking everyone not to feed the birds. Congregating birds equals congregating bird feces and this can be a health issue.
Local and state governments are working to reduce the stormwater impacts on our local estuaries – which trigger other problems as well as high bacteria counts. Local residents and businesses can do the same.
References
Lewis, M.J., J.T. Kirschenfeld, T. Goodhart. 2016. Environmental Quality of the Pensacola Bay System: Retrospective Review for Future Resource Management and Rehabilitation. U.S. Environmental Protection Agency. Gulf Breeze FL. EPA/600/R-16/169.
BMAP
https://floridadep.gov/dear/water-quality-restoration/content/basin-management-action-plans-bmaps.
Florida Friendly Landscaping
Restoring the Health of Pensacola Bay, What You Can Do to Help? – Florida Friendly Landscaping
http://blogs.ifas.ufl.edu/escambiaco/2018/06/08/restoring-the-health-of-pensacola-bay-what-can-you-do-to-help-a-florida-friendly-yard/.
Septic Systems
Maintain Your Septic Tank System to Save Money and Reduce Water Pollution
https://nwdistrict.ifas.ufl.edu/nat/2017/04/29/maintain-your-septic-system-to-save-money-and-reduce-water-pollution/.
Septic Tanks: What You Should Do When a Flood Occurs
https://nwdistrict.ifas.ufl.edu/nat/2018/05/04/septic-systems-what-should-you-do-when-a-flood-occurs/.
by Rick O'Connor | Jul 6, 2018
The manatee may be one of the more iconic animals in the state of Florida. In Wyoming, we think of bison and bears. In Florida, we think of alligators and manatees. However, encountering this marine mammal in the Florida panhandle is a relatively rare occurrence… until recently.
Manatee swimming in Big Lagoon near Pensacola.
Photo: Marsha Stanton
For several years now, visitors to Wakulla Springs – in the eastern panhandle – have had the pleasure of viewing manatees on a regular basis. It is believed about 40 individuals frequent the river. Last year there were eight individuals that frequent the Perdido Key area, and a couple more were seen more than once near Gulf Breeze. This is not normal for us, but already this year one manatee has been spotted in the Big Lagoon area – so we may be seeing more as the summer goes on.
So what exactly is a manatee?
It is listed as a marine mammal, but frequents both fresh and saltwater habitats. Being mammals, they are warm blooded (endothermic). Maintaining your body temperature internally allows you to live in a variety of cold temperature habitats but water can really draw the heat quickly from anyone’s body. Marine mammals counter this problem by having a thick layer of fat within the skin – insulation called blubber. However, the manatees blubber layer is not very thick. So they are restricted to the tropical parts of the world and, in Florida, spend the winter near warm water springs. Many have learned the trick of hanging out near warm water discharges near power plants. In the warmer months, they venture out to find lush seagrass meadows in which to graze.
They are herbivores. Possessing flat-ridged molars for grinding plant material, they are more closely related to deer and cattle than the seal and walrus they look like. They lack canines and incisors, which deer and cattle use to cut the grass blades, but have large extending lips that grab and tear grasses with – very similar to the trunk of an elephant, which is their closest relative. Like many mammalian herbivores, they grow to a large size. Manatees can reach 15 feet in length and over 1000 pounds. They have two forearms that are paddle shaped and used for steering. The tail is a large circular disk called a fluke, which propels them through the water and is often seen breaking the surface. They are generally slow moving animals but can startle you when they decide to kick into “fourth gear” and burst across the river.
They are generally solitary animals, gathering in the wintertime around the warm springs. Males usually leave the females after breeding and do not form family units, or herds. Females are pregnant for 13 months and typically give birth to one calf, which stays with mom for two years. Like all mammals, the young feed on milk from mammary glands, but these glands are close to the armpits on the manatee. This makes it much easier for the calf to feed while both are swimming. This is not the case with dolphins and whales, where the mother must roll sideways to feed her young.
Manatees hanging out in Wakulla Springs.
Photo provided by Scott Jackson
There are three species of manatees in the world today. The Amazonian Manatee (Trichechus inunguis), the West African Manatee (Trichechus senegalensis) and the West Indie Manatee (Trichechus manatus). The Florida Manatee is a subspecies of the West Indian (Trichechus manatus latirostris). In the 1970’s it was estimated there were about 1000 West Indian manatees left in the word. Today, with the help of numerous nonprofits and state agencies, there is an estimated 6600 in Florida. Due to this increase, the manatee has moved from the federal endangered species list to threatened species. That said, human caused mortality still occurs and boaters should be aware of their presence. Since 2012, an average of 500 manatees die in Florida waters. Most of these are prenatal or undetermined, but about 20% are from boat strikes. Manatees tend stay out of the deeper channels, so boats leaving the ICW for a favorite beach or their dock should keep an eye out. Most of the time they are just below the surface and only their nostrils break for a breath of air. They usually breathe every 3-5 minutes when swimming but can remain below for up to 20 minutes when they are resting. Approaching a manatee is still illegal. Though their status has changed from endangered to threatened, they are still protected by state and federal law.
FWC suggest the following practices for boaters, and PWC, near manatees
- Abide by any speed limit signs – no wake zones
- Wear polarized sunglasses to aid in seeing through the water
- Stay in deeper water and channels as much as possible
- Stay out of seagrass beds – there is are numerous reasons why this is important, not just manatees
- If a manatee is seen, keep your boat/PWC at least 50 feet from the animal.
- Please do not discard your hooks and monofilament into the water – again, numerous reasons why this is a bad practice.
So Why are There More Encounters in the Florida Panhandle?
Good question…
Their original range included the entire northern Gulf coast. When their numbers declined in the 1960’s and 70’s there were fewer animals to venture this far north. Manatee sightings at that time did occur, but were very rare. Today, with increasing numbers, encounters are becoming more common. There is actually a Manatee Watch Program for the Mobile Bay area (https://manatee.disl.org/) and they have been seen as far west as Louisiana.
They are truly neat animals and to see one in our area is a real treat. Remember to view and photo, but do not approach. I hope that many of you will get to meet what maybe new summer neighbors.
Manatee swimming by a pier near Pensacola.
Photo: Marsha Stanton
References
2017 Manatee Mortality Data. Florida Fish and Wildlife Conservation Commission. http://myfwc.com/media/4132460/preliminary.pdf.
Florida Manatee Facts and Information. Florida Fish and Wildlife Conservation Commission. http://myfwc.com/education/wildlife/manatee/facts-and-information/.
Manatee Information for Boaters and PWC. Florida Fish and Wildlife Conservation Commission. http://myfwc.com/education/wildlife/manatee/for-boaters/.
Manatee Sighting Network. https://manatee.disl.org/.
West Indian Manatee. Wikipedia. https://en.wikipedia.org/wiki/West_Indian_manatee.
by Rick O'Connor | Jul 6, 2018
This week’s article is a bit different… it is about nature we hope you DO NOT see – but hope you let us know if you do. Most of you know that Florida, along with many other states, continually battle invasive species. From Burmese pythons, to lionfish, to monitor lizards, we have problems with them all. Many of our invasive species are plants, which grow aggressively and take over habitats. They have few, if any, predators to control their populations and can cause environmental or economic problems for us.
The pretty, but invasive, beach vitex. Photo: Rick O’Connor
The best way to tackle an invasive species is to detect it when it first arrives and remove it as quickly as possible – this provides you the best chance of actually eradicating it from an area at the lowest cost. One such invasive plant that has recently invaded Escambia and Santa Rosa county beaches is Beach Vitex (Vitex rotundifolia).
Beach vitex is a vine that grows along the surface of sandy areas, like dunes. It has a main taproot from which the runners (stolons) extend in a radiating pattern, like a skinny-legged starfish. The stolons will develop secondary roots, which can form smaller deep root systems, and the entire maze of vines grows very quickly in the summer. The leaves are ovate, more round than elongated, and have a grayish-blue-green color to them – they tend to stand out from other plants. The plant can grow vertically to about three feet, giving it a bush appearance.
Another key characteristic for identification are the lavender flowers it produces, few other plants in our dunes do – so this is a good thing to look for. The flowers appear in late spring and summer. They are actually quite pretty. In the fall, the flowers are replaced by numerous large seeds, which form in clusters where the flowers were. These seeds are problematic in that they can remain viable for up to six months if they fall into the water – increasing their chance for dispersal.
So what is the problem?
In the Carolina’s this species was planted intentionally. They quickly learned of its aggressive nature and have had a state task force to battle it. The plant is allopathic – it can release toxins that kill neighboring plants allowing them to move into that space – this includes sea oats. Beach vitex has a taproot system, unlike the fibrous one of the sea oat, and cannot stabilize a dune as well – which is a problem during storms. In the Carolina’s there are numerous beach fronts where this is the only plant growing, a problem waiting to happen. Though there are no reports of it happening, it also has the potential to affect sea turtle nesting.
Beach Vitex Blossom. Photo credit: Rick O’Connor
So what do I do if I see it?
Contact us… You can contact me at roc1@ufl.edu, or call (850) 475-5230. Try to give us the best description of where the location is as you can. Many phones now come with an app that has a compass. This app also gives you your latitude and longitude. If your phone does not have this, again, give us the best description of the location you can. If you can include a photograph, that would be great. There are numerous other invasive species roaming our area, and you are welcome to report any you find to us. We hope to stay on top of these early arrivals and keep them under control.
by Rick O'Connor | Jul 6, 2018
Shrimp, oysters, blue crab and fish have been harvested from the Pensacola Bay System (PBS) for decades, although there has been a decline in all in recent years. Annual landings (in pounds) have ranged from
- Fish 66,000 – 4,600,000 (most are scaienids)
- Brown shrimp 43,000 – 906,000
- Oysters 0 – 492,000
- Blue crab 400 – 137,000
There is a concern about the safety of seafood harvested from our estuary… sort of. Many local residents and visitors ask frequently about the safety of these products. However, when programs are held to provide this information they are not well attended, and when articles are posted – few view them. I think there is a concern for the safety of seafood products, particularly those from our estuaries – so I cannot explain the lack of interest in the presentations and articles.
Commercial seafood in Pensacola has a long history.
Photo: Rick O’Connor
One contaminant that gets a lot of press is mercury. The toxic form of mercury is methylmercury. This form of mercury impairs brain development of fetuses – hearing, vision, and muscle function in adults. Studies suggests that the primary source of mercury in the waters of the PBS is the atmosphere. Advisories have been issued for Escambia, Blackwater, and Yellow Rivers. There have also been advisories for local largemouth and king mackerel. This is one of the metals whose concentrations within the PBS is higher than neighboring estuaries – especially in our bayous (see https://blogs.ifas.ufl.edu/escambiaco/2018/06/13/restoring-the-health-of-pensacola-bay-what-can-you-do-to-help-bioaccumulation-of-toxins/.) Florida Department of Environmental Protection (FDEP) has issued Total Maximum Daily Loads (TDMLs) for mercury in the PBS.
So How Much is Too Much?
For monitoring purposes, total mercury (THg) is easier and less expensive to than the toxic form methylmercury (MHg). Many believe the amount of THg is equivalent to the concentration of MHg, and so it is used as a proxy for MHg.
Both the U.S. EPA and the FDEP recommend concentrations of THg not be higher than 0.3 ppm, and 0.1 ppm for pregnant women (or women planning a pregnancy).
Fish
Since 2000, four studies have been conducted on six species of fish in the PBS. Concentrations of THg ranged from 0.02 – 0.88 ppm and averaged between 0.2 – 0.4 ppm.
Blue Crab
Two studies have been conducted since 2007 found mercury concentrations ranged from 0.07 – 1.1 ppm.
Oysters
30 years ago, studies were finding concentrations of THg in oysters around 0.02 ppm. Repeated studies between 1986 and 1996 found an increase to 0.3 ppm.
Overall
Studies suggest that shrimp and oysters have lower concentrations of THg than blue crab and fish.
Seafood has a long history along Florida’s panhandle.
Photo: Betsy Walker
How often have samples exceeded the safe levels suggested by EPA, FDEP, and FDA?
| Group |
Recommended highest level |
% of times samples from PBS exceeded this limit |
| Subsistence Fishermen |
0.049 ppm |
50-90%
(89% for blue crab and oysters) |
| Pregnant females |
0.1 ppm |
50-90%
(88% for blue crab) |
| General public |
0.3 ppm |
5-20%
(12% for blue crabs)
(27% for fish) |
| Food and Drug Administration recommendation |
1.0 ppm |
0% |
The concern for mercury in local seafood has led to a reduction of consuming all seafood by pregnant women – period. Recent studies have shown this can have negative effects on the developing baby as well. The recommendation is to avoid fish that have been tested high in THg. Most of these are high on the food chain – such as king mackerel, shark, and swordfish. You can find the latest on seafood safety and advisories at https://myescambia.com/our-services/natural-resources-management/marine-resources/seafood-safety. Another piece of this story is the belief, by many, that selenium can lower the toxicity of MHg. Many believe that molar ratios of selenium and mercury greater than 1.0 can reduce the toxicity. However, there have been no studies on molar ratios of these elements in the PBS.
The bottom line on this issue is to be selective on the seafood products you consume.
The most popular seafood species – shrimp.
Reference
Lewis, M.J., J.T. Kirschenfeld, T. Goodhart. 2016. Environmental Quality of the Pensacola Bay System: Retrospective Review for Future Resource Management and Rehabilitation. U.S. Environmental Protection Agency. Gulf Breeze FL. EPA/600/R-16/169.
by Rick O'Connor | Jun 22, 2018
Just a decade ago, few people would have known what a gopher tortoise was and would have hard time finding one. But today, because of the protection they have been afforded by the state, they are becoming more common. This is certainly an animal you might see visiting one of our state parks.
This gopher tortoise was found in the dune fields on a barrier island – an area where they were once found.
Photo: DJ Zemenick
The gopher tortoise is one of only two true land dwelling turtles in our area and is in a family all to its own. They are miners, digging large burrows that can extend up to a depth of 7 feet and a length of 15 feet underground. However, tortoises are not very good at digging up towards the surface, so there is only the one entrance in and out of the burrow. The burrow of the tortoise can be distinguished from other burrowing animals, such as armadillos, in that the bottom line of the opening is flat – a straight line – and the top is domed or arched shaped; mammalian burrows are typically round – circular. Tortoise burrows also possess a layer of dirt tossed in a delta-shaped fan out away from the entrance (called an apron). Many times the soil is from deeper in the ground and has a different color than the soil at the surface. The general rule is one burrow equals one tortoise, though this is not always true. Some burrows are, at times, shared by more than one and some may not be occupied at all. Many field biologists will multiple the number of burrows by 0.6 to get an estimate of how many tortoises there are in the area.
The tortoise itself is rather large, shell lengths reaching 15 inches. They can be distinguished from the other land dwelling turtle, the box turtle, by having a more flattened dome to the shell and large elephant like legs. The forelimbs are more muscular than the hind and possess large claws for digging the burrow. They are much larger than box turtles and do not have hinged plastrons (the shell covering the chest area) and cannot close themselves up within the shell as box turtles can. Tortoises prefer dry sandy soils in areas where it is more open and there are plenty of young plants to eat; box turtles are fans of more dense brush and wooded areas.
Tortoises spend most of the day within their burrows – which remain in the 70°F range. Usually when it is cooler, early morning or late afternoon, or during a rain event – the tortoises will emerge and feed on young plants. You can see the paths they take from their burrows on foraging trips. They feed on different types of plants during different type times of the year to obtain the specific nutrients. There are few predators who can get through the tough shell, but they do have some and so do not remain out for very long. Most people find their burrows, and not the tortoise. You can tell if the burrow has an active tortoise within by the tracks and scrap marks at the entrance. Active burrows are “clean” and not overgrown with weeds and debris. Many times, you can see the face of the tortoise at the entrance, but once they detect you – they will retreat further down. Many times a photo shot within a burrow will reveal the face of a tortoise in the picture. There is a warning here though. Over 370 species of creatures use this burrow to get out of the weather along with the tortoise – one of them is the diamondback rattlesnake. So do not stick your hand or your face into the entrance seeking a tortoise.
Most of the creatures sharing the burrow are insects but there are others such as the gopher frog and the gopher mouse. One interesting member of the burrow family is the Eastern Indigo Snake. This is the largest native snake to North America, reaching a length of eight feet, and is a beautiful iridescent black color. It is often confused with the Southern Black Racer. However, the black racer is not as long, not as large around (girth), and possess a white lower jaw instead of the red-orange colored one of the indigo. The indigo is not dangerous at all, actually it feeds on venomous snakes and it is a good one to have around.
Federal and state laws protect the indigo, as with the gopher frog and mouse. All of these animals have declined in number over the past few decades. This is primarily due to loss of the needed gopher burrows, which have declined because the tortoises have declined, and this is due to habitat loss and harvesting. Again, tortoises like dry sandy soils for digging burrows. They prefer wooded areas that are more open and allow the sun to reach the forest floor where young grasses and flowers can grow. The longleaf pine forest is historically the place to find them but they are found in coastal areas where such open wooded areas exist. The lack of prescribe burning has been a problem for them. Florida is the number one state for lightning strikes. Historically, lightning strikes would occasionally start fires, which would burn the underbrush and allow grasses to grow. In recent years, humans have suppressed such fires, for obvious reasons, and the tortoise community has suffered because of it. Therefore, we now have prescribe fire programs on most public lands in the area. This has helped to increase the number of tortoises in the area and your chance of seeing one.
All of the members of the tortoise community are still protected by state, and – in the case of the indigo snake – federal law, so you must not disturb them if seen. Photos are great and you should feel lucky to have viewed one. Though they could be found anywhere where it is high, dry, and somewhat open – the state and national parks are good places to look.
Reference
Meylan, P.A. (Ed.). 2006. Biology and Conservation of Florida Turtles. Chelonian Research Monographs No. 3, 376 pp.
