Simplify the following text for a Grade 9 native English-speaking person.
Original: Between 1808 and 1860 , the British West Africa Squadron seized approximately 1,600 slave ships and freed 150,000 Africans who were aboard .
Simplified: Between 1808 and 1860 , the British Navy captured approximately 1,600 slave ships and freed 150,000 Africans who were aboard .