Eels 101
Lifecycle
Why Eels?
Management
Ecology
100
Eels are classified as this type of animal.
What are fish?
100
Scientists believe than an adult female American eel can lay this many eggs during spawning.
What is 10 million?
100
American eels are directly tied to this, something every living thing depends on.
What is clean water?
100
Unregulated harvesting and poaching, construction of dams, sediment and nutrient pollution and habitat loss are all examples of what?
What are current threats to the American eel?
100
Without healthy American eel populations, freshwater mussel populations also decline, resulting in poorer this.
What is water quality?
200
This type of fin is elongated down the back of the eel, quite different than a shark's!
What is the dorsal fin?
200
This third life stage, pictured below, is when eels are elongated and transparent, and are often illegally poached for a high price.
What are glass eels?
200
How many dams are on the first 60 miles of the Susquehanna River, moving upstream from the Chesapeake Bay
What is four?
200
The scientist in this photo is scanning for this, a device inserted just underneath the eel's skin that allows scientists to monitor population movement.
What are trackers or tags?
200
Eels are native to this watershed that accounts for 43% of water that reaches the Chesapeake Bay.
What is the Susquehanna River watershed?
300
American eel eggs are laid here, the only sea bound by ocean currents and not land mass.
What is the Saragasso Sea?
300
The eels you have in your tank are in this life stage, pictured below, and approximately 2-5 years old.
What are elvers?
300
These Native American tribes in the Susquehanna River watershed used eels as a food source, and later taught harvesting techniques to the first colonists.
What are the Haudenosaunee and Susquehannock Nations?
300
This is an example of what type of device that can help eels move over dams that block their migration.
What is an eel ladder?
300
American eels are opportunistic feeders and carnivores, eating aquatic macroinvertebrates, small fish, and these small crustaceans that swim backwards when spooked.
What are crayfish?
400
Eels are this type of fish, meaning their eggs are laid in the ocean and they migrate to freshwater to live most of their lives.
What are catadromous fish?
400
While the eels do not reach maturity until they are ready to return to the ocean, female adult eels are usually larger than male adult eels, which is known as this term in biological science.
What is sexual dimorphism?
400
The eels in your tank came from this large hydroelectric dam in Maryland, the first dam on the Susquehanna River.
What is the Conowingo Dam?
400
There are over this many dams on the Susquehanna River that block or hinder American eel migration.
What is two dozen?
400
While the American eel migration journey was first officially documented in 2015, the journey for this type of eel wasn't documented until 2022, which is also born in the Saragass Sea but travels in the opposite direction after hatching.
What is the European Eel?
500
Researchers often refer to the American eel as this, its scientific name.
What is Anguilla rostrata?
500
This second life stage, pictured below, means "narrow-head", with a body shape flat like a willow leaf as the eel drifts along the ocean currents towards the coast of North America.
What is leptocephali larva?
500
The image below from Google Earth depicts these, still visible and commonly used by Native Americans to trap and responsibly harvest eels.
What are weirs?
500
The map below depicts this in South Central Pennsylvania, a conservation method used to repopulate American eels above dams (in red) that block their migration.
What are restocking methods?
500
American eels serve as an intermediate host for this type of freshwater mussel by letting the young grow in its gills for a short period of time.
What is the Eastern Elliptio mussel?