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Soup of the Sea
Plankton are organisms that drift with currents. Plankton can be plant-like phytoplankton or animal-like zooplankton. Most plankton are small, but even larger organisms are considered plankton if they live their lives drifting with currents. Plankton is found in freshwater and saltwater all over the earth, and it is very important to humans.
Thank your plankton
Imagine your favorite seafood - shrimp - crab, oysters, fish ... thanks to phytoplankton, we can enjoy this mouthwatering cuisine from the sea. Phytoplankton provides two things that are essential for animals (including us) to live. One is food. Like plants on land, they use sunlight and nutrients to produce food. They're the base of the food chain in the ocean. Many tiny animals eat phytoplankton and, in turn, get eaten by larger animals, up the food chain. Without plankton, we would not have seafood.
Now, take a deep breath. The second essential ingredient produced by phytoplankton is oxygen. Estimates vary, but most scientists agree that phytoplankton makes up a significant portion of the air on Earth.
There's a zoo out there.
Zooplankton eat. Many eat phytoplankton, and many eat smaller zooplankton. They are an important part of the food chain. A shark may never eat plankton and has no idea it exists but it depends on plankton for all of its food.
Many zooplankters go through a metamorphosis. Some of them are plankton for part of their lives and then grow large enough to swim against currents or settle to the bottom. Those are called meroplankton. Holoplankton are plankton their whole lives.
You might recognize the adult forms of many meroplankters. See if you can match the adult forms with their planktonic forms below.
Broth of the Bay
Look up at Mobile Bay. These are some of the planktonic organisms that are common in the bay.
Plankton is collected with special nets like this one. The nets have tiny holes and are pulled along the water's surface.
Crabs go through metamorphosis, much like butterflies or frogs. The megalops is one larval stage for crabs.
Bristle worms get their name from their many bristles that are used for movement. They are related to earthworms.
Dinoflagellates are phytoplankton. Some of them can glow like fireflies. Some make toxins that can be harmful to humans when there are lots of dinoflagellates in the water.
Diatoms are phytoplankton. They produce glass-like skeletons that are used in a variety of products. The grit in your toothpaste might come from diatoms.
This is a nauplius, a larval form that is common to many different crustaceans, including barnacles.
Copepods are thought to be the most abundant animals on earth.
They are found in salt and fresh water and even in damp soil.
They are incredibly strong for their size.
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Saving and Restoring our Seagrasses
Threats to Seagrass
Nearly 80% of all seagrasses in coastal Alabama have been lost since the 1950s.
A constant threat to seagrass beds is scarring created by boats' propellers and anchors. When boaters navigate across shallow areas or anchors. In seagrass beds, deep scars are created that can take years to recover leading to erosion and further loss of seagrass. Poor water quality is also a major factor that poses a serious threat to the health of seagrass. For example, excessive sediments in the water limit the light perpetration necessary for plant survival.
How can we protect our seagrasses?
What are we Doing?
To help propeller scars heal and protect seagrass beds from further scarring local partners are implementing protection and restoration projects throughout lower Perdido Bay including Little Lagoon the island near Perdido Pass and Ole River.
No motor and sensitive seagrass area signs will identify seagrass beds to help boaters navigate through or around shallow water sites containing seagrass.
The scientist is using bird stakes to attract local waterfowl whose guano deposits will provide natural fertilizer to the propeller scars to promote the growth and expansion of surrounding seagrass.
What can you do?
Be aware of idle or raised motors and poles when navigating through shallow areas.
Set anchors in sandy areas avoiding seagrass beds.
Obey No Motor Zone or Sensitive Seagrass areas signs: wade, troll, pole, or kayak when navigating through these areas to your favorite fishing or beach spot.
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Seagrasses Coastal Nursery Habitats
What are seagrasses
Seagrasses are flowering plants that live in the shallow waters of every continent except Antarctica.
Seagrass beds containing shoal grass and turtle grass are found in Alabama's calm and shallow coastal waters.
Why are seagrasses important?
Seagrass beds provide food and protection for juvenile fish and shellfish including many economically important species such as speckled trout, redfish, blue crabs, and shrimp.
Many types of waterfowl feed on seagrasses as do threatened and endangered species, such as manatees and green turtles.
Seagrasses help stabilize bottom sediment filter runoff and absorb nutrients from surrounding landscapes.
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Alabama's Coastal Connection
Migratory Birds
In search of food and shelter
Each fall, millions of birds leave North America and cross the Gulf of Mexico, to spend the winter in South and Central America and the island of the Caribbean. In the spring they make the return flight to their Northern American breeding grounds. Alabama's Gulf Coast provides an important rest stop for these travelers. Stopover areas are a key element in maintaining bird populations.
With increased development along the entire Gulf Coast, tracts of diverse, forested lands such as these are disappearing.
Migratory species as well as resident birds, use this diverse landscape for foraging, resting, and evading predators. Birds must find enough food to provide energy for the long-distance flight to nesting sites far north. Migratory butterflies are dependent on food such as paw, paw, and passion flower larval growth. Songbirds feed on insects and berries while shorebirds hunt for invertebrates in the mudflats.
The western end of the Fort Morgan peninsula is an important stopover site for migratory birds and has become a nationally known hotspot for birders. When adverse weather forces birds to the ground during a spring "fallout," the birding can be spectacular, although treacherous for the exhausted birds that must find a safe place to recover.
Bird species commonly seen during migration include vireos, warblers, flycatchers, buntings, and hummingbirds, The Monarch butterfly migration can also be breathtaking during fall when weather conditions are favorable.
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Alabama's Coastal Connection
Permeable Parking
A better way to go
Combined sewer systems are remnants of the country's early infrastructure and so are typically found in older communities. Combined sewer systems are designed to collect rainwater runoff, domestic sewage, and industrial wastewater in the same pipe. Most of the time, combined sewer systems transport all of their wastewater to a sewage treatment plant, where it is treated and then discharged to a water body. Heavy rainfall adds stormwater so that the wastewater volume in a combined sewer system exceeds the capacity of the system.
Combined sewer systems are designed to overflow occasionally and discharge excess untreated wastewater directly to nearby streams, rivers, or other water bodies.
These combined sewer overflows, also contain untreated human and industrial waste, toxic materials, and debris.
The expansion of impermeable surfaces associated with urban sprawl and automobiles has so increased the stormwater volumes that the combined systems are being separated at great expense. The result is that stormwater runoff that used to receive treatment at the plants is now being delivered to receiving streams and coastal estuaries like Mobile Bay.
Water running off of roads, bridges, and parking lots has been estimated to be the largest volume of untreated wastewater in this country. Even twenty years ago the Federal Highway Administration estimated that 25 million tons of rubber wear off the nation's tires every week-50 tons/week in Alabama. Since rubber is biodegradable the process of biodegradation consumes oxygen when it occurs in streams and estuaries. Also of concern are the heavy metals found in steel-belted radial tires, oil, antifreeze, or even transmission fluid.
The parking lot at the Estuarium allows all stormwater and associated contaminants to percolate down through the gravel providing an enormous surface area for microbial treatment of the waste, returning it to the water and carbon dioxide. Any contaminated waste that remains cannot reach the shallow freshwater aquifers that lead either to the Bay or Dauphin Island community wells because an impermeable membrane four feet down traps it and sends it through a filter system that removes the hydrocarbon contaminants. The water and any overflows of the system then flow into a detention pond where the vegetation, including the common cane, and other plants remove any nutrients that contribute to low dissolved oxygen levels in the Bay.
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