marsh bordering the creek. Two additional stations were situated in an 

 adjacent diked marsh that is managed for salt hay production. One is 

 in a drainage ditch, and the other is on the S^. patens marsh. The total 

 number of individuals ranged from 36-1 ,594/1 Ocm^ and the dry weight 

 biomass from 0. 62-17. 59mg/10cm2. Free living nematodes, which comprised 

 78.3 percent of the total numbers and 62.3 percent of the biomass, 

 were the most abundant organisms collected at all the stations but those 

 located in the middle and upper reaches of Dividing Creek. Harpacticoid 

 copepods were second in overall abundance, comprising 14.8 percent 

 of the total numbers and 14.7 percent of the total biomass, and were 

 the most abundant organism at the remaining two stations. 



Total population values were highest in the late spring and summer, 

 and lowest in the winter. Nematodes inhabiting the creek did not exhibit 

 a distinct seasonal pattern. Copepod abundance was related to repro- 

 ductive cycles and predation pressure by members of the macrofauna and 

 natant forms. The meiofauna were restricted to the upper layers of 

 the substrate by the strongly reducing character of the sedimentary 

 environment except at the marsh stations where oxygenation of the sedi- 

 ment by the Spartina root systems occurred. 



Thirty-five species of harpacticoid copepods were collected during 

 the survey. Pseudobradya pulchera , Scotolana canadensis , and Paro- 

 nychocamptus huntsmani dominated the fauna in Dividing Creek. Nannopus 

 palustris , Nitocra spinipes , Schizopera knabeni and Sigmatidium minor 

 were dominant in the S. aTterniflora marshT CTetocamptus bicoTor was 

 dominant in the drainage ditch; and Nitocra spinipes . in the S^. patens 

 marsh. Four distinct harpacticoid assemblages are described: mesohaline 

 estuary, salt marsh, drainage ditch, and modified salt marsh. The 

 degree of physical stress within the ecosystem is reflected by the low 

 overall diversity of the harpacticoid copepod communities. Except 

 for the diked marsh, the meiofauna inhabiting the Dividing Creek 

 watershed reflect the high productivity of the estuarine environment. 

 (A.A.) 



Keywords: food chain, Spartina alterniflora , £. patens , meiofauna, 

 estuary. New Jersey 



III-E-10 



Adams, S.M., and J.W. Angelovic. 1970. Assimilation of detritus and 



its associated bacteria by three species of estuarine animals. 



Chesapeake Science 11:249-254. 



The assimilation of detritus and its associated bacteria by three 

 species of macrofauna that are abundant in eel grass beds during the 

 summer was investigated in a laboratory study. The amount of carbon 

 dioxide respired per milligram of dry body weight by animals that fed 

 on different types of labeled food was compared to determine the relative 

 amount of assimilation of a particular food. Animals were fed sterilized 



127 



