Common Loon
Recording from Stokes & Stokes.
The loon call jumps a perfect fifth from D (yellow) to A (blue/purple). The second call repeats the fifth and completes the octave up to the yellow high D.
Once in a canoe I came upon a loon making this call; for a few minutes the calls grew higher and more urgent.
Ultimately a youngling appeared, the two paddled off, and I realized it was my proximity that had caused the calls in the first place.