Ask an Ecologist!
What do fireflies and the estuary have in common?
If you want to learn about the lands, rivers, and sounds of the Albemarle-Pamlico ecosystem, you’ve come to the right place! Through “Ask an Ecologist,” we’ll answer your environmental questions. In particular, we’ll highlight the interesting ecological relationships between the air, land, water, and biological communities of our region. We’ll also help you understand how we as humans affect and rely on our ecosystem.
Submit a question using the form to the left and have your question personally answered by a nearby expert. We’ll address as many submissions as possible, but responses may take a week or more. Also note that we don’t do school homework, and we try to select questions for reply that are focused on the science of ecology. The best questions and responses will be posted to the APNEP website, along with the submitter’s first name and hometown.
Is there a link between the use of fertilizers and water quality in our estuaries?
Nutrients by definition provide nourishment essential for growth and the maintenance of life. Humans require all kinds and amounts of nutrients, including proteins, fats, carbohydrates, and vitamins. Plants, including those in your yard, likewise require a select amount and type of nutrients to live, and often require additional amounts (a fertilizer boost) to thrive. The link between fertilizer use and water quality comes when the landscape receives too much of a good thing, that is more nutrients than the plants and soils can process. During heavy rains and snowmelt that surplus is whisked away by surface flows into our waterways.
In moderation, these mobile nutrients are utilized by the submerged and wetland plants that live downstream. Nitrogen and phosphorus are two of the most important. Those mobile nutrients not absorbed by the plants, however, can feed an explosion of unwanted algae. This algae blocks sunlight for aquatic plants, leads to a lack of dissolved oxygen in the water, and may kill fish in the area.
There are many ways to reduce these impacts, including carefully and moderately fertilizing your yard. In response to your question, we'll be tweeting several tips on this subject in the months ahead.
The scientific term for the evolution of new species due to physical separation is allopatric speciation and the feature that divides these populations is known simply as a reproductive barrier. The organisms on either side of this divide are described as vicariant, meaning they are unable to share genetic material between populations. Over the generations this results in genetic drift and the formation of new species.
Like other places around the world, the physical features of the Albemarle-Pamlico region can influence the genetics of its inhabitants. Shad and other anadromous fish hatch in our rivers and swim to the ocean, returning to the same river several years later to spawn. Because they and past generations have returned to the same river, the stock of fish in each river system has a distinctive genetic code. To maintain this genetic distinctness, the US Fish & Wildlife Service hatchery in Edenton is used to stock shad in the Roanoke River, while the Service hatchery in Watha is used to stock shad in the Neuse River.
The endangered red wolf, which once ranged throughout the southeast, has been reintroduced on the Albemarle-Pamlico peninsula. This area is also home to coyotes. The lack of a physical barrier allows these distinct species to mate and hybridize, which threatens the red wolf recovery effort. Today, management efforts focus on providing a safe haven for red wolves by maintaining a coyote-free zone. In the absence of a reproductive barrier between these species, we’re doing our best to maintain one!
Fireflies (also known as lightning bugs) are under consideration by APNEP as an invertebrate indicator of ecosystem health in our region’s upland areas. These insects provide a “cultural” ecosystem service, specifically the aesthetic appeal of their glowing and flickering torsos during warm season evenings.
Like other insects, fireflies also have an important role in the region’s carbon cycle. When fireflies die and decompose, a large proportion of the resulting organic material is carbon. A fraction of the carbon works itself into the soil matrix, thus facilitating productive soils. Another portion of this carbon is taken up by water flowing over the landscape. This non-living carbon can be a food source for flora and fauna in our streams and rivers, ultimately finding its way to the estuary and the species living there.
If only the estuarine waters could flicker like a firefly as a result!
Are omnivores primary consumers, secondary consumers or both?
Greetings from North Carolina John,
My answer to your question, whether ominvores are a primary consumer, secondary consumer, or both: omnivores are both. When an ominivore is in herbivorous mode and eating vegetation it’s a primary consumer (of producers, the plants) and when they are in carnivorous mode and eat herbivores they are secondary consumer. Of course, if an omnivore dines on carnivores they would be a tertiary or higher-level consumer as well!