Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_204_778 ( id number, "code" number, "county" text, "former province" text, "area (km2)" number, "population\ncensus 2009" number, "capital" text )

### Question ###
did mombasa or tana river have a larger population in 2009 ?

### Accurate SQL ###

SELECT "county" FROM table_204_778 WHERE "county" IN ('mombasa', 'tana river') ORDER BY "population\ncensus 2009" DESC LIMIT 1