Bird Sudoku Level 90 Hint
Pick a row, column, or habitat with a low remaining count, then check which of its perch cells are blocked by open diagonal flight lines.
Bird Sudoku Level 90 Strategy
Medium Level 90 uses a 8x8 board with 21 perch cells, 7 blockers, and 9 habitats. Use the row and column counts first, then test each open diagonal flight line.
Bird Sudoku Level 90 Solution
Bird positions in the solution: R1C6, R3C2, R3C3, R3C5, R5C8, R6C8, R7C1, R7C5, R7C8.