The fact that the spinner has a circular current loop implies that it could be the spinal column of a distant cousin to the original seaswallower. Perhaps this cousin used to float around the ocean filtering microorganisms through its' giant "wings". Naturally, it found refuge in the stomach of the seaswallower, where it was safe from predators, and was also supplied with a permanent amount of water and energy with which to collect food. Genetic testing of this hypothesis is still in the works.
Regardless of the potential for a symbiotic relationship, the electro-magnetic explanation of the cause of the seaswallower's whirlpool is consistent with some important observable facts. Seaswallowers have extremely long life spans, which would simply not seem possible if the whirlpool had to be generated by any other mechanism. Muscular tissue is relatively fragile, and subject to more atrophy over time then the electrical spin system of the seaswallower. So long as the rest of the beast holds up, the seaswallower will continue to swallow.