Royal Netherlands Institute for Sea Research

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Phytoplankton series

This series of microscopic images illustrates the yearly rhythm of phytoplankton in the Marsdiep. Although for each month a characteristic species has been selected January 2004 up to December 2006, it is incorrect to assume that phytoplankton development and succession is similar each year.

January

Pediastrum | Freshwater green-algae, among which Pediastrum cells, are common in the Marsdiep.

February

Odontella aurita | Survives the winter at the bottom of the Marsdiep, but rises to the surface in spring.

March

Thalassionema pseudonitzschioides | Often the first species of the diatom bloom in early spring.

April

Rhizosolenia hebetata f. semispina | The many sparkling needles could even be seen with the naked eye.

May

Haptophyta Phaeocystis globosa | takes its chance and starts to reproduce at a very high rate.

June

Noctiluca scintillans | When the sea shines at night this phytoplankton species is inhabiting our waters.

July

Guinardia delicatula | If you think that algae do not suffer from illness, you are wrong.

August

Guinardia striata | Hardly any nutrients remain available for algae growth after the spring bloom.

September

Chaetoceros socialis | Renewed phytoplankton growth usually occurs in September.

October

Coscinodiscus wailesii | The largest diatom of the Marsdiep (and of the North Sea).

November

Bacteriastrum hyalinum | Each organism has its own strategy to survive harsh times.

December

Odontella sinensis | Several colorless bell-shaped ciliates (Vorticella) uses this large diatom as a taxi driver.