Bubiai lake (or Šiauliai sea, Bubiai marios) is a body of water in northern Lithuania, Šiauliai district, 6-10 km southwest of Šiauliai, formed at Bubiai, near the Bubiai mound, dammed at Pailiai village, 132 km from the mouth of the Dubysa and Ringuva rivers. The rising water flooded Jonelaičiai (75.9 ha), Raizgii (25.8 ha) and Balniaus (8.1 ha) lakes, Spalve stream. Dubysa and Švendrel flow out of the pond.