ninespine stickleback, pungitius pungitius, little and tender freshwater wild fish swims in biotope aquarium with potamogeton

adult algae animal aqua aquarium aquatic biotope clear closeup current ecology europe european fauna fish fishkeeping free freshwater funny gasterosteidae gravel grey habitat head ichthyology inhabitant instinct little local macro native natural nature ninespine ornamental plant plants potamogeton protection pungitius river salvinia sand shallow shy space spine stickleback swims tank temperate tender threat typical ukraine underwater vegetation water waters weed widespread wild