expt_block  date        mussel_density  prey_eaten  carap_width  sex  parasite  
10          2012-07-26  2               2           12.2         F    No        
10          2012-07-26  4               2           11.5         F    No        
10          2012-07-26  6               0           13.8         M    No        
10          2012-07-26  8               8           12.5         M    No        
10          2012-07-26  10              10          10.8         F    No        
10          2012-07-26  16              3           11.1         M    No        
10          2012-07-26  24              13          14.1         F    No        
10          2012-07-26  32              11          12.8         F    No        
10          2012-07-26  2               1           14.4         M    Yes       
10          2012-07-26  4               0           10.4         F    Yes       
10          2012-07-26  6               0           12.1         F    Yes       
10          2012-07-26  8               1           13           F    Yes       
10          2012-07-26  10              2           10.5         F    Yes       
10          2012-07-26  16              0           11.7         M    Yes       
10          2012-07-26  24              3           11.6         F    Yes       
10          2012-07-26  32              1           12.1         F    Yes