Two main types of enumeration error were experienced in the use of an immunofluorescence protocol for identification of the picoplankter Aureococcus anophagefferens from western New York Bight coastal waters. Microscopist discrimination was affected when cells were too numerous to count reliably or too lightly stained to be identified. This was remedied by sample dilution, and increase of antisera and stain concentration and incubation time. The second type, extensive clustering of A. anophagefferens cells in monospecific clumps, and as embeds in floc matrices, was much more problematic. To remedy this, cell disaggregation was sought through mechanical and chemical treatments. A single treatment effective for all samples was not found but various treatment combinations greatly improved enumeration. Varied efficacy of treatment regimes among samples suggests that cell binding strength was variable.

National Marine Fisheries Service (NMFS)