Collins Pond fish population subject of Smithsonian research

Collins Pond, on the border of Georgetown and Bridgeville, recently became one of 35 sites in Delaware and Maryland for a Smithsonian Environmental Research Center study on river herring populations.

A small crew, led by ecologist Matthew B. Ogburn, aims to determine the presence or absence of river herring in Chesapeake Bay tributaries.

River herring, which includes two very similar species, is a fish that is born in fresh water, such as streams or rivers, and live most of their lives in salt water, returning to fresh water systems to spawn. Alewife and Blueback Herring are the two species being studied, Ogburn said in a press release.

"Over the past several decades, river herring numbers along the Atlantic coastline from North Carolina to Canada have declined significantly, leading to closures of fisheries including those in the Chesapeake Bay," he said. "The central question of the study is why is the decline in certain streams and not others? And if one species disappears, how will it affect other species?"

The research project is funded by the National Fish and Wildlife Foundation and the Smithsonian Institution. In 2015 and 2016, 200 site studies are being conducted throughout the Chesapeake Bay watershed. This year, the study has expanded to the 725,000-acre Nanticoke River Watershed, which begins in southern Delaware.

Ogburn said the study includes field work and collecting samples of fish eggs and larvae. A DNA test, which will analyze the presence of herring DNA in water samples, is under development.

Along with Collins Pond and other Nanticoke River watershed ponds and tributaries are surveys of the Northeast, Gunpowder, Patapsco and Patuxent watersheds in Maryland and the James and Mattaponi Rivers in Virginia.

"Although we are not sampling for pollutants, we want to know why herring spawn in certain streams and not others," Ogburn said.

Completed study results are expected in the fall.