SEA 



SCIENCE 



Larry Crowder (center) and graduate students examine fish from a Pamlico Sound trawl. 



levels that remain on the bottom of the 

 sound and estuaries?" 



Additionally, upriver habitat is still 

 recovering from the triple dose of storm 

 upheaval. If sea grasses — habitat for gag 

 grouper — do not make a comeback, this 

 year's class of fish could be affected. 



The jury still is out on overall effects to 

 North Carolina fisheries, researchers and 

 state officials agree. Mother Nature's final 

 answer will depend on the prevailing 

 weather in spring and early summer. 



Warm sunny days could feed algal 

 blooms with more light. Organic materials 

 and fungi will use oxygen to decompose. A 

 wet, warm spring and summer could add 

 more fresh water and nutrients. 



What is the best case scenario? A dry 

 and windy spring could evaporate fresh 

 water trapped in the Pamlico and promote 

 its recovery, Crowder says. 



The researchers find themselves in new 

 territory as they evaluate the cumulative 

 effects of Hurricanes Dennis, Floyd and 



Irene, which hit the North Carolina coast 

 within a four-week span in late summer and 

 early fall. Scientists have limited data from 

 1 954- 1 955 — when four hurricanes hit 

 North Carolina in a 12-month period — to 

 help predict how the fisheries will recover. 



'This is an opportunity to do 

 groundbreaking research that will help 

 predict, but more importantly help guide 

 management policies of how to manage our 

 resources at a time of greater levels of 

 disturbance," Crowder says. 



THE PAMLICO PUZZLE 



A small armada of scientists will 

 continue studying the hurricane effects up 

 and down the coastline. The interdiscipli- 

 nary effort — including several Sea Grant- 

 funded studies — began with a rapid 

 response. 



"We virtually commandeered the Duke 

 and UNC research vessels," Hans Paerl, a 

 Sea Grant researcher at the University of 

 North Carolina's Institute for Marine 



Sciences, recalls the days after Floyd hit. 



Researchers teamed up with state 

 agencies to launch an immediate assess- 

 ment of water quality and fisheries habitat 

 in the Pamlico Sound — the nation's 

 second largest estuary and deemed by many 

 to be the state's most valuable aquatic 

 resource. 



The Pamlico processes nearly half of 

 the state's freshwater runoff via its 

 subestuaries — Neuse, Pamlico, Roanoke- 

 Chowan- Albemarle. But that process is 

 slow — with a mean water retention time 

 of about one year, Paerl says. 



Academic researchers parlayed their 

 resources with teams from the state's 

 ongoing Neuse River Modeling and 

 Monitoring Program (ModMon), and 

 NOAA's fisheries lab in Beaufort. The fleet 

 of researchers already was on the scene 

 with cameras and monitoring devices as 

 Floyd's deluge inundated the sound and 

 swollen freshwater tributaries, and flushed a 

 dark brown plume of sediments and organic 

 waste into the Pamlico. 



Early measurements caused concern 

 because the salinity levels of the Pamlico 

 plummeted. Bottom-water measurements 

 indicated low oxygen and elevated 

 inorganic nitrogen and algal production 

 levels in the western sound. The Pamlico 

 had virtually stratified, with a freshwater 

 layer atop a salt-water bottom layer. Trawls 

 of the region yielded dead and dying shrimp 

 and blue crabs, and bloated fish with tail rot, 

 skin sloughing and lesions. 



Hurricane Irene arrived as a mixed 

 blessing. Though already-flooded eastern 

 North Carolina was wont to receive another 

 dousing, Irene's winds "stirred" the 

 Pamlico, mixing salt and fresh waters and 

 temporarily releasing oxygen to stressed 

 finfish and shellfish. 



Stratification reoccurred and oxygen 

 and salinity levels remain lower than 

 normal, but massive fish kills did not 

 happen. And through the winter months, 

 signs of disease dropped. 



Continued 



COASTWATCH 25 



