While Surfing in this area, you might encounter Tentacool, Wingull, and Pelipper. If you use the Old Rod, you might catch Tentacool or Magikarp. With the Good Rod, you can catch Tentacool, Magikarp, and Wailmer. With the Super Rod, you can find Sharpedo and Wailmer.
Explore the Route
Near the entrance of the route, you find Swimmer Grace, who in Ruby and Sapphire has a Marill, Wailmer, and Wingull. in Emerald, she has a Marill, and she might join Swimmer Declan in a Double Battle. He has a Gyarados.
To the south, you can find Sis and Bro Rita & Sam, or in Emerald, Sis and Bro Lila and Roy. They have Chinchou and Carvanha.
To the northeast, you can find Swimmer Spencer, who in Ruby and Sapphire has three Tentacool, or in Emerald has a Tentacool and a Wingull.
To the east, there is Swimmer Jenny, who has a Wailmer.
East of Jenny, there is a small island, and east of that, there is another island. The second island has the house of the Diving Treasure Hunter, who will exchange shards for Evolutionary Stones.
Southwest of the treasure hunter's house, you find Swimmer Roland, who has a Carvanha. In Emerald, he might be joined by Triathlete Isabella, who has a Staryu.
Near the southeast part of the route, you can find Swimmer Chad, who in Ruby and Sapphire has Wingull and Wailmer, and in Emerald has Tentacool and Wailmer.
In the southeast of the route, you can walk onto the sand to reach Mossdeep City.