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The Results Of Bacteriological Examinations 
Carried Out During Research Cruises 31.07.-07.08.97 And 23.08.-28.08.97 
- Results From The Pomeranian Bight - 
Malgorzata Michalska & Maria Krolska 
Institute of Maritime and Tropical Medicine 
ul. Powstania Styczmowego 9B 
81355 Gdynia 
Abstract 
During the research cruises on board the ship r/v Baltica, which took place between 31.07 and 
7.08 and between 23.08 and 28.08.97 on the Pomeranian Bay waters, 186 sea water samples 
for bacteriological examination were collected The following Index of bacteria contamination 
were determined: 
1. standard plate count on an agar ZoBell’s 2216 E culture medium at 37°C and 20 °C, 
2. determination of the total coliform group by the fermentative tube method (Most Probable 
Number method), 
3. determination of the faecal coliform by the fermentative tube method (Most Probable 
Number method), 
4. determination of the sulphite - reducing spore-forming anaerobes (Clostridia) by membrane 
filtration method, 
5. detection and enumeration of Salmonella and Shigella using double-strength selenite F 
medium at 37°C, bismuth sulphite agar and Salmonella - Shigella agar, 
6. detection and enumeration of faecal Streptococci by membrane filtration method, 
7. detection and enumeration of Staphylococci by membrane filtration method, 
8. detection and enumeration of Pseudomonas by membrane filtration method. 
Altogether 1302 determine were made. 
Results 
On the basis of analysis of examinations results a high number of heterotrophic bacteria (both 
at 37°C and 20°C) was observed especially in the region of the Swina and Dziwna mouths and 
to the west of the Swina mouth. Such a high number of bacteria results from additional supply 
of nutrient substances brought on by the Odra river and is also an evidence of intensive organic 
substance degradation. Strong winds blowing on 05-06.08.97 caused partial sediment 
turbulence and due to that fact the number of bacteria in water significantly increased. This 
periodical increase in the number of bacteria may have also been brought about by water 
turbidity. Suspended matter protects the bacteria form being destroyed by light, contributing in 
this way to their development. Values of coliform and faecal coliform indexes were the highest 
(24 000 in 100 ml of water) in the region of the Swina and Dziwna mouths and to the west of 
the (Ewina mouths. It confirms the faecal contamination of water and probable water 
contamination with disease bacteria. No Salmonella and Shigella were found in samples 
collected during the first cruise. Other, potentially pathogenic bacteria of Enterobacteriaceae 
type such as: Citrobacter freundii, Klebsiella oxytoca, Enterobacter cloacea, Enterobacter 
agglomérons, Serratia marcescens were found. Salmonella rods {Salmonella agona, 
Salmonella enteritidis) were found during the second cruise as well as Enterobacteriaceae type 
bacteria such as Citrobacter freundii, Klebsiella oxytoca, Klebsiella ozaenae, Enterobacter 
cloacea, Enterobacter agglomérons, Proteus vulgaris.