The song of the Antrarctic Weddell seal is wild!
You can see they have a massive range in the spectogram showing a big drop, so clearly their song has range as lower pitches use more energy.
Listening to it and I sense the reverberance of their singing underwater, that's the metallic ringing effect.
It might be clicks that become like lazer gun sounds, the latter being made tapping on metal wires so it might be the soundwave bouncing back through the water from the ice?
Wonder if this is their dawn chorus or maybe a seasonal song?