Beat the butter and sugar together until light and fluffy. Add the eggs, one at a time, mixing well after each addition. Stir in the flour and baking powder and mix until smooth.
Rinse the blueberries and pat dry. Fold the shredded coconut and blueberries into the batter and pour into the prepared loaf pan. Bake in an oven preheated to 180°C (approximately 350°F) for 35-40, until a toothpick inserted comes out clean. Remove from the oven and let stand for about 15 minutes before turning out of the loaf pan. Cool completely on a wire rack and dust with powdered sugar before slicing and serving.