This is a dataset used for the paper entitled "Do marine planktonic ciliates follow Bergmann’s rule?" by Liu et al. This dataset includes the mean cell-size of ciliate community obtained from 282 samples from 154 stations covered from 20°S to 65°N. It also contains the biomass of ciliate community, the corresponding environmental parameters including seawater temperature and Chlorophyll a concentration (Chla), and the proxy for phytoplankton (prey) size estimated by two methods (see paper for details). 

Samples for ciliate biomass and size were collected from each station and preserved with acidic Lugol’s solution (final concentration 5%). All samplesd were observed by inverted microscope. Dimensions were determined and volumes were calculated after each cell was assigned a geometrical shape. The equivalent spherical diameters (ESD) was calcuated for each ciliate and the geometric mean ESD was calcuated for each sample. 

Chlorophyll a concentration was determined by filtering 100 to 500 mL of seawater, following methods outlined by Welschmeyer (1994). The phytoplankton size was estimated by two methods: the phytoplankton size fractions based on the model of Ward (2016) and the phytoplankton mean size.

More details are in the paper "Do marine planktonic ciliates follow Bergmann’s rule?"