Dolphins and their handlers going through their paces at a closed section of Resorts World Sentosa's Marine Life Park last Thursday.
The dolphins have yet to be unveiled to the public, and RWS has said people will get to see them only next year.
The park is now home to 24 dolphins. Three have died in the past two years. Wen Wen, a 10-year-old dolphin, died last month while being flown in from the Philippines.
Animal welfare groups here have opposed the keeping of dolphins at the park, but the park says their acquisition and care meet or surpass international guidelines.