Astronomy

By John Harrod, Manager, DuPont Environmental Education Center

Today while participating in a school field study at the DuPont Environmental Education Center, a student caught a young Amercian eel at a stage known as an elver.

American Eel. Photo by Lesley Bensinger.

A student holds an American eel elver. Photo by Lesley Bensinger.

The American eel hatches in the ocean waters of the Sargasso Sea in the North Atlantic between the West Indies and the Azores. It moves from its birth place to mature in fresh or brackish water and then returns to the sea to spawn. American eels range from Greenland to South America, occurring in all major streams along the coastline.  

American eel by Ellen Edmonson and Hugh Chrisp

American eel adult by Ellen Edmonson and Hugh Chrisp

 Join us at DEEC Tuesdays – Sundays at 2pm for a free netting program to see what you can find in the marsh. For more sightings follow DEEC on Twitter.

By John Harrod, Manager, DuPont Environmental Education Center 

Through this past spring, summer and fall, program participants had the joy of finding a sundry of fish at the DuPont Environmental Education Center. Species included brown bullhead catfish, yellow perch, pumpkinseed, and striped bass. 

One species we did not come across is the Atlantic sturgeon. The Atlantic sturgeon is a prehistoric fish that is listed as an endangered species by the State of Delaware. The Delaware River once supported the largest Atlantic sturgeon fishery along the Atlantic Coast. The population collapsed prior to the turn of the 19th century due to factors including overfishing and poor water quality. 

Atlantic sturgeon. Credit: U.S. Fish and Wildlife Service, Duane Raver.
Prehistoric Atlantic sturgeon. Credit: U.S. Fish and Wildlife Service, Duane Raver.

Things are looking up for this ancient fish.  In the summer of 2009, a small Atlantic sturgeon was caught in a net by Matthew Fisher, Delaware Fisheries Biologist, which had not happened in 5 decades. This provided evidence that Atlantic sturgeon could be spawning in the Delaware Estuary.  One possible spawning location was identified one mile downstream from Wilmington in the Delaware River.

Join us Thursday, February 10, 6:30pm at the DuPont Environmental Education Center for the lecture Atlantic Sturgeon: Historic Problems and Recovery Efforts by Dewayne Fox, Associate Professor of Fisheries Science at Delaware State University.  Learn more about the Atlantic sturgeon’s fascinating life, historic problems and current recovery efforts.  Take home a free copy of Delaware’s Freshwater and Brackish-water Fishes: A Popular Account, by Maynard Raasch.

By John Harrod, Manager, DuPont Environmental Education Center

Over the summer and last weekend at WildFest, Blue Crabs were caught in the DuPont Environmental Education Center’s freshwater tidal pond. Most visitors were surprised to find crabs here since they are usually associated with brackish (slightly salty) and salt water along the Atlantic and Gulf coasts.

An excited summer camper with a Blue Crab. Photo by John Harrod.

  Blue crabs can live in fresh water. To find out the salinity content of our pond, I borrowed a refractometer from the Delaware Nature Society’s technical monitoring program. The pond registered a salinity reading of 0 parts per million (ocean water is 32+ ppm).

Pete Zeigler demonstrating use of a hand refractometer. Photo by John Harrod.

 Growing up to 9 inches, this crustacean is an opportunistic bottom-dwelling predator that feeds on anything it can find including live and dead fish, clams, snails, and detritus (decayed organic matter).

A recent catch at WildFest that could grow up to 9 inches. Photo by Laura Orth.

 This predator is also prey of wildlife including eel, striped bass, other blue crabs and catfish. As its scientific name – Callinectes sapidus – indicates, people enjoy them too. It translates, “beautiful swimmer that is savory.”

 To learn more about DNS technical monitoring program visit here.

By John Harrod, Manager, Dupont Environmental Education Center
 
This past Thursday was a great fall day for an outing on the Christina River with a clear sky and a light breeze. On this day, the Delaware Nature Society led a late afternoon historic river cruise. Participants were treated to accounts of the river by Sally O’Byrne, DNS naturalist and co-author of Wilmington’s Waterfront.

 

Some happy boaters by John Harrod

Some happy boaters by John Harrod

Sally O’Byrne’s details of the waterfront’s history was extensive and informative, but as a summary,  it has a very rich industrial history that includes building the first iron hulled yacht to win the America’s Cup and making significant contributions to the navel efforts of WWII. 

Christina River ship building remnants by John Harrod

Christina River ship building remnants by John Harrod

Being on the water allowed us views not often seen riverfront including Swedes landing. I am going to let the photos do the rest of the talking. Enjoy the pictorial journey!
Swedes Landing by John Harrod

Swedes Landing by John Harrod

 

 

 

 

 

Christina landing by John Harrod

Christina landing by John Harrod

 

 

 

 

 

 

Boat at sunset by John Harrod

Boat at sunset by John Harrod

 

 

 

 

 

 

 

Justison landing at dusk by John Harrod

Justison landing at dusk by John Harrod

 

 

 

 

 

 

 

 

If you would like to spend some time on the  Christina River, DNS has a canoe trip this Saturday, October 31st that puts in the water near Churchman’s marsh and paddes down to the DuPont Environmental Education Center. For details visit: http://www.delawarenaturesociety.org/fp09_adult.html#deec.