 |
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 worldwide and is essential 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 essential things 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 make up a significant portion of Earth's atmosphere.
There's a zoo out there.
Zooplankton eat. Many eat phytoplankton, and many eat smaller zooplankton. They are an essential 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 of the larval stages of 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 produce toxins that can harm humans when there are many 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 stage common to many crustaceans, including barnacles.
Copepods are thought to be the most abundant animals on Earth.
They are found in salt and fresh water, as well as in damp soil.
They are powerful for their size.
|
 |
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 anchor. In seagrass beds, deep scars can form that take years to heal, leading to erosion and further seagrass loss. Poor water quality is also a significant factor that poses a serious threat to seagrass health. For example, excessive sediments in the water limit the light penetration 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 for the propeller scars, promoting 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.
|
 |
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.
|
 |
Alabama's Coastal Connection
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 islands of the Caribbean. In the spring, they make the return flight to their Northern American breeding grounds. Alabama's Gulf Coast provides a critical 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 and 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 depend on food such as pawpaw and passion fruit for 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.
Commonly seen bird species during migration include vireos, warblers, flycatchers, buntings, and hummingbirds. The Monarch butterfly migration can also be breathtaking in the fall, when weather conditions are favorable.
|
 |
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 convey all wastewater to a sewage treatment plant, where it is treated and then discharged into a water body. Heavy rainfall adds stormwater, causing the wastewater volume in a combined sewer system to exceed its capacity.
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 delivered to receiving streams and coastal estuaries, such as Mobile Bay.
Water running off roads, bridges, and parking lots has been estimated to be the largest source 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, 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 feed either the Bay or the 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 system overflows then flow into a detention pond, where vegetation, including standard cane and other plants, removes nutrients that contribute to low dissolved oxygen levels in the Bay.
|
