Tintinnids and other microzooplankton — seasonal distributions and relationships to resources and hydrography in a Maine estuary

Species composition and abundance of tintinnids and other microzooplankton were studied in the Damariscotta River estuary, Maine, USA during the period March 1981 to May 1982. Peak tintinnid abundances occurred during spring and summer and exceeded 7 × 10 3 I −1 . Spearman rank correlation coefficients indicated that temperature, nanoplankton chlorophyll and phaeopigments passing a 20 μn filter were important factors correlating with total tintinnid density. Species composition of tintinnids changed seasonally and was similar in the spring of both years. Non-loricate ciliates were also most abundant in the spring, reaching peak densities of 4.5 × 10 4 I −1 in April 1982. Rotifers were most common upestuary in the spring.