by Rick O'Connor | May 4, 2018
Humans have inhabited the shores of Pensacola Bay for centuries. Impacts on the ecology have happened all along, but the major impacts have occurred in the latter half of the 20th century. There has been an increase in human population, an increase in development, a decrease in water clarity, a decrease in seagrasses, and a decrease in the abundance of some marine organisms – like horseshoe crabs, scallops, and some marine fishes. There has also been an increase in inorganic and organic compounds from stormwater run-off, fish kills, and health advisories due excessive nutrients and fecal bacteria in local waters.
A view of Pensacola Bay from Santa Rosa Island.
Photo: Rick O’Connor
Since the 1970’s, there have been efforts to help restore the health of the bay. Seagrasses have returned in some areas, fish kills have significantly reduced, and occasionally residents find scallops and horseshoe crabs – but there is still more to do. In this series of articles, I will present information provided in a recent publication (Lewis, et. al. 2016) and from citizen science monitoring. We will begin with an introduction to the bay itself.
The Pensacola Bay System is the fourth largest estuarine system in the state of Florida. The system includes Blackwater, Escambia, East, and Pensacola Bays. There are numerous smaller bayous, such as Indian, Mulat, and Hoffman, and three larger ones, which include Texar, Chico, and Grande. There are two lagoons that extend east and west of the pass. To the west is Big Lagoon and to the east is Santa Rosa Sound. The surface area of this bay system is about 144 mi2 and the coastline runs about 552 miles in length. There are four rivers that discharge into the system: the Escambia, Blackwater, Yellow, and East Rivers. The majority of watershed is in Alabama and covers about 7000 mi2. The mouth of the bay is located at the Pensacola Pass near Ft. Pickens and is 0.5 miles across. Depending on the source, the flush time for the entire bay has been reported between 18 and 200 days.
There are several ecosystems found within the bay system. Seagrasses are be found throughout the bay and bayous, but are more prevalent in Big Lagoon and Santa Rosa Sound. Oyster reefs have provided income for some in the East Bay area in the past, but production has declined in the last 50 years. Salt marshes are found throughout the bay as well, but the greatest acreage is in the Garcon area of Santa Rosa County. There are, of course, freshwater marshes near the mouths of the rivers with the largest being at the mouth of the Escambia River.
Members of the herring family are ones who are most often found during a fish kill triggered by hypoxia.
Photo: Madeline
Members of the drum family are one of the more common fishes found in the system and would include fish like the Spot and Atlantic Croaker. However, speckled trout, striped mullet, redfish, several species of flounder, have also been targets for local fishermen. Target fish include sardines, silversides, stingrays, pinfish, and killifish. Brown shrimp, oysters, and blue crab have historically provided a fishery for locals, but other invertebrates include several species of jellyfish, stone crabs, fiddler crabs, hermit crabs, grass shrimp, several species of snails, clams, bay squid, octopus, and even starfish. There is also a variety of benthic worms found within the sediments.
A finger of a salt marsh on Santa Rosa Island. The water here is saline, particularly during high tide. Photo: Rick O’Connor
There has been a decline in overall environmental quality since 1900 but, again, the biggest impacts have been between 1950 and 1970. Fish kills, a reduction in shrimp harvest, and hypoxia (a lack of dissolved oxygen) have all been problems.
In the articles to follow we will look deeper into specific environmental topics concerning the health of Pensacola Bay.
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.
by Erik Lovestrand | Feb 2, 2018
Sorting and re-caging take place on-site at the lease
Photo: Erik Lovestrand
There are a number of parallels than can be drawn between shellfish farming and traditional forms of agriculture that take place on the land. The most obvious similarities are the amount of hard work, grit and faith that are required of the farmer on land or sea. In spite of this there are many “salty” farmers in the Florida Panhandle who have mustered the faith requirement and are now putting in the hard work necessary to help build this budding industry in the Southeastern U.S.
Market demand for quality oysters has continued to outstrip available supplies for several years of late. This has been due in part to better marketing strategies employed by growers as well as clientele becoming aware of the health benefits of fresh oysters; a great supply of important vitamins and minerals, including vitamin C and B vitamins, zinc, selenium and iron. However, supply/demand ratios are not the only important factor in developing a thriving oyster aquaculture industry. Also required, is the necessary infrastructure to support the grower’s equipment needs, enough sources of baby oyster “seed”, a reliable refrigerated transportation network for live shellfish, and the support of regulatory agencies in making water leases available in suitable growing areas.
Fortunately, the stars seem to be aligning for many of these industry-growth necessities and the business of oyster farming is gaining a firmer foundation to build upon. One of the important milestones for Florida was the approval of “full-water-column” leases, which allows the use of floating oyster cages or bags. Previously, oysters were required to be grown on the bay bottom and this made them susceptible to higher levels of predation from crabs and snails and severe biofouling (barnacles and algae) on the exterior of the mesh bags. Heavy biofouling reduces the water flow through the oyster’s growing environment, thus the available food for this filter feeding bivalve.
One critical need for this industry is the availability of quality “seed” (baby oysters) to put in the growing waters. Seed oysters are supplied by hatcheries where oyster brood stocks are spawned and babies are raised to the necessary age for grower needs. Some growers use baby oyster larvae that have not settled and attached yet. These “eyed larvae” are put in a tank with old oyster shell and allowed to attach on the shells, which are then deployed at a lease site. Other growers use seed that has already attached to a small particle of crushed shell and are sold as individual oysters to be placed in grow-out bags or cages. The more recent development of oyster stocks with 3 sets of chromosomes (triploids) have provided growers with an oyster that gets to market size faster. Triploid oysters are infertile and do not use energy for spawning, thereby putting more energy into shell and tissue growth. Federal and state laws also govern where growers can buy their seed in an effort aimed at stopping the spread of shellfish disease from one body of water to another (i.e. Atlantic to Gulf of Mexico, etc.).
Even if all of the hardware and infrastructure is in place, there is still one other factor that plays a significant role in whether an oyster farmer will be successful. Just like the dairy farmer, the cattle rancher, the cotton or peanut grower, or the blueberry producer; backbreaking labor is necessary for many stages of the production cycle. Oyster growers work their leases either bending over the gunnels of a boat or actually being in the water, lifting heavy bags or cages of shellfish, sorting by size, re-caging, and moving lots of materials to and from the lease area. True grit and a dogged determination to stay on top of things, regardless of unpleasant conditions, are vital to raising a successful crop of oysters. And by the way, don’t forget that Mother Nature will have the final word. As all farmers know, they are required to be a good listener when she speaks.
by Carrie Stevenson | Nov 3, 2017
Red mangrove growing among black needlerush in Perdido Key. Photo credit: Carrie Stevenson, UF IFAS Extension
Discovering something new is possibly the most exciting thing a field biologist can do. As students, budding biologists imagine coming across something no one else has ever noticed before, maybe even getting the opportunity to name a new bird, fish, or plant after themselves.
Well, here in Pensacola, we are discovering something that, while already named and common in other places, is extraordinarily rare for us. What we have found are red mangroves. Mangroves are small to medium-sized trees that grow in brackish coastal marshes. There are three common kinds of mangroves, black (Avicennia germinans), white (Laguncularia racemosa), and red (Rhizophora mangle).
Black mangroves are typically the northernmost dwelling species, as they can tolerate occasional freezes. They have maintained a large population in south Louisiana’s Chandeleur Islands for many years. White and red mangroves, however, typically thrive in climates that are warmer year-round—think of a latitude near Cedar Key and south. The unique prop roots of a red mangrove (often called a “walking tree”) jut out of the water, forming a thick mat of difficult-to-walk-through habitat for coastal fish, birds, and mammals. In tropical and semi-tropical locations, they form a highly productive ecosystem for estuarine fish and invertebrates, including sea urchins, oysters, mangrove and mud crabs, snapper, snook, and shrimp.
Interestingly, botanists and ecologists have been observing an expansion in range for all mangroves in the past few years. A study published 3 years ago (Cavanaugh, 2014) documented mangroves moving north along a stretch of coastline near St. Augustine. There, the mangrove population doubled between 1984-2011. The working theory behind this expansion (observed worldwide) is not necessarily warming average temperatures, but fewer hard freezes in the winter. The handful of red mangroves we have identified in the Perdido Key area have been living among the needlerush and cordgrass-dominated salt marsh quite happily for at least a full year.
Key deer thrive in mangrove forests in south Florida. Photo credit: Carrie Stevenson, UF IFAS Extension
Two researchers from Dauphin Island Sea Lab are planning to expand a study published in 2014 to determine the extent of mangrove expansion in the northern Gulf Coast. After observing black mangroves growing on barrier islands in Mississippi and Alabama, we are working with them to start a citizen science initiative that may help locate more mangroves in the Florida panhandle.
So what does all of this mean? Are mangroves taking over our salt marshes? Where did they come from? Are they going to outcompete our salt marshes by shading them out, as they have elsewhere? Will this change the food web within the marshes? Will we start getting roseate spoonbills and frigate birds nesting in north Florida? Is this a fluke due to a single warm winter, and they will die off when we get a freeze below 25° F in January? These are the questions we, and our fellow ecologists, will be asking and researching. What we do know is that red mangrove propagules (seed pods) have been floating up to north Florida for many years, but never had the right conditions to take root and thrive. Mangroves are native, beneficial plants that stabilize and protect coastlines from storms and erosion and provide valuable food and habitat for wildlife. Only time will tell if they will become commonplace in our area.
If you are curious about mangroves or interested in volunteering as an observer for the upcoming study, please contact me at ctsteven@ufl.edu. We enjoy hearing from our readers.
by Carrie Stevenson | Aug 25, 2017
Life on the Gulf Coast can be beautiful, but has its share of complications. Photo credit: Carrie Stevenson, UF IFAS Extension
Life on the coast has tremendous benefits; steady sea breezes, gorgeous beaches, plentiful fishing and paddling opportunities. Nevertheless, there are definite downsides to living along it, too. Besides storms like Hurricane Harvey making semi-regular appearances, our proximity to the water can make us more vulnerable to flooding and waterborne hazards ranging from bacteria to jellyfish. One year-round problem for those living directly on a shoreline is erosion. Causes for shoreline erosion are wide-ranging; heavy boat traffic, foot traffic, storms, lack of vegetation with anchoring roots, and sea level rise.
Many homeowners experiencing loss of property due to erosion unwittingly contribute to it by installing seawalls. When incoming waves hit the hard surface of the wall, energy reflects back and moves down the coast. Often, an adjacent homeowner will experience increased erosion and bank scouring after a neighboring property installs a seawall. This will often lead that neighbor to install a seawall themselves, transferring the problem further.
Erosion can damage root systems of shoreline trees and grasses. Photo credit: Carrie Stevenson, UF IFAS Extension
Currently, south Louisiana is experiencing significant coastal erosion and wetlands losses. The problem is compounded by several factors, including canals dredged by oil companies, which damage and break up large patches of the marsh. Subsidence, in which the land is literally sinking under the sea, is happening due to a reduced load of sediment coming down the Mississippi River. Sea level rise has contributed to erosion, and most recently, an invasive insect has caused large-scale death of over 100,000 acres of Roseau cane (Phragmites australis). Add the residual impacts from the oil spill, and you can understand the complexity of the situation.
Luckily, there are ways to address coastal erosion, on both the small and large scale. On Gulf and Atlantic beaches, numerous coastal communities have invested millions in beach renourishment, in which offshore sand is barged to the coast to lengthen and deepen beaches. This practice, while common, can be controversial because of the cost and risk of beaches washing out during storms and regular tides. However, as long as tourism is the #1 economic driver in the state, the return on investment seems to be worth it.
On quieter waters like bays and bayous, living shorelines have “taken root” as a popular method of restoring property and stabilizing shorelines. This involves planting marsh grasses along a sandy shore, often with oyster or rock breakwaters placed waterward to slow down wave energy, and allow newly planted grasses to take root.
Locally in Bayou Grande, a group of neighbors were experiencing shoreline erosion. Over a span of 50 years, the property owners used a patchwork of legally installed seawalls, bulkheads, rip rap piles, private boat ramps, piers, mooring poles and just about anything else one can imagine, to reduce the problem. Over time, the seawalls and bulkheads failed, lowering the property value of the very property they were meant to protect and increasing noticeable physical damage to the adjacent properties.”
Project Greenshores is a large-scale living shoreline project in Pensacola. Photo credit: Carrie Stevenson, UF IFAS Extension
In 2011, a group of neighboring property owners along the bayou decided to take action. After considering many repair options, the neighbors decided to pursue a living shoreline based on aesthetics, long-term viability, installation cost, maintenance cost, storm damage mitigation and feasibility of installation. By 2017, the living shoreline was constructed. Oyster shell piles were placed to slow down wave energy as it approached the transition zone from the long fetch across the bayou, while uplands damage was repaired and native marsh grasses and uplands plants were restored to slow down freshwater as it flowed towards the bayou. Sand is now accruing as opposed to eroding along the shoreline. Wading shorebirds are now a constant companion and live oysters are appearing along the entire 1,200-foot length. Additionally the living shoreline solution provided access to resources, volunteer help, and property owner sweat equity opportunities that otherwise would have been unavailable. An attribute that has surprisingly appeared – waterfront property owners are now able to keep their nicely manicured lawns down to within 30 feet of the water’s edge. At that point, the landscape immediately switches back to native marsh plants, which creates a quite robust and attractive intersection. (Text and information courtesy Charles Lurton).
Successes like these all over the state have led the Florida Master Naturalist Program to offer a new special topics course on “Coastal Shoreline Restoration” which provides training in the restoration of living shorelines, oyster reefs, mangroves, and salt marsh, with focus on ecology, benefits, methods, and monitoring techniques. Keep an eye out for this course being offered near you. If you are curious about living shorelines and want to know more, reach out to the Florida Department of Environmental Protection Ecosystem Restoration section for help and read through this online document.
by Rick O'Connor | Aug 11, 2017
Our first POL program will happen this week – August 17 – at the Navarre Beach snorkel reef, and is sold out! We are glad you all are interested in these programs.
Well! We have another one for you. The Natural Resource Extension Agents from UF IFAS Extension will be holding a two-day water school at St. Joseph Bay. Participants will learn all about the coastal ecosystems surrounding St. Joe Bay in the classroom, snorkeling, and kayaking. Kayaks and overnight accommodations are available for those interested. This water school will be September 19-20. For more information contact Extension Agent Ray Bodrey in Gulf County or Erik Lovestrand in Franklin. Information and registration can be found at https://stjosephbay-waterschool.eventbrite.com.
by Rick O'Connor | Jul 29, 2017
ARTICLE BY DR. MATT DEITCH; water quality specialist – University of Florida Milton
Summer is a great time for weather-watching in the Florida panhandle. Powerful thunderstorms appear out of nowhere, and can pour inches of rain in an area in a single afternoon. Our bridges, bluffs, and coastline allow us to watch them develop from a distance. Yet as they come closer, it is important to recognize the potential danger they pose—lightning from these storms can strike anywhere nearby, and can cause fatality for a person who is struck. Nine people were killed by lightning strike in Florida in 2016 alone, more than in any other state. Because of the risk posed by lightning, my family and I enjoy these storms up-close from indoors.
Carpenter’s Creek in Pensacola
Photo: Dr. Matt Deitch
A fraction of the rain that falls during these storms is delivered to our bays, bayous, and estuaries through a drainage network of creeks and rivers. This streamflow serves several important ecological functions, including preventing vegetation encroachment and maintaining habitat features for fish and amphibians through scouring the streambed. High flows also deposit fine sediment on the floodplain, helping to replenish nutrients to floodplain soil. On average, only about one-third of the water that falls as rain (on average, more than 60 inches per year!) turns into streamflow. The rest may either infiltrate soil and percolate into groundwater; or be consumed and transpired by plants; or evaporate off vegetation, from the soil, or the ground surface before reaching the soil. Evaporation and transpiration play an especially large role in the water cycle during summer: on average, most of the rain that falls in the Panhandle occurs during summer, but most stream discharge occurs during winter.
The water that flows in streams carries with it many substances that accumulate in the landscape. These substances—which include pollutants we commonly think of, such as excessive nutrients comprised of nitrogen and phosphorus, as well as silt, oil, grease, bacteria, and trash—are especially abundant when streamflow is high, typically during and following storm events. Oil, grease, bacteria, and trash are especially common in urban areas. The United States EPA and Florida Department of Environmental Protection have listed parts of the Choctawhatchee, St. Andrew, Perdido, and Pensacola Bays as impaired for nutrients and coliform bacteria. Pollution issues are not exclusive to the Panhandle: some states (such as Maryland and California) have even developed regulatory guidelines in streams (TMDLs) for trash!
Many local and grassroots organizations are taking the lead on efforts to reduce pollution. Some municipalities have recently publicized efforts to enforce laws on picking up pet waste, which is considered a potential source of coliform bacteria in some places. Some conservation groups in the panhandle organize stream debris pick-up days from local streams, and others organize volunteer citizens to monitor water quality in streams and the bays where they discharge. Together, these efforts can help to keep track of pollution levels, demonstrate whether restoration efforts have improved water quality, and maintain healthy beaches and waterways we rely on and value in the Florida Panhandle.
Santa Rosa Sound
Photo: Dr. Matt Deitch
