Seeing dolphins
Seeing dolphins from a boat or a beach lets you watch animals that never fully switch off: they rest one half of the brain at a time, often with one eye open. Italian lore cast dolphins as angels thrown out of heaven.
What it may mean
Sleep is a risky business for a dolphin, because nothing about its breathing happens by itself. Every breath is a decision: the animal has to rise, open its blowhole and close it again. So it never switches off completely. One half of the brain rests while the other stays awake enough to keep surfacing, often with one eye open, and later the halves trade places. Lots of people carry something like that, a task they have to do on purpose while everyone else manages it without thinking: speaking a second language all day, finding their way in a new job, remembering every name in a family they have just married into. It is tiring in a way nobody sees from the outside. Watching a pod roll past, you might give yourself some credit for the things you can never do half asleep.
Depending on how you saw it
Dolphins near surfers
Surfers at Huntington Beach told a student that when dolphins show up during a session, sharks are probably not around and the day will go well. The belief puts nervous beginners at ease. Whose presence makes you feel that the water is safe enough to paddle out?
Music on deck
An English folk saying held that dolphins love music. It is a pleasant thought to keep in mind at a ship's rail. If you hoped something wild would come closer, which song would you play?
A pod beside a ferry
Dolphins often swim alongside or ahead of boats, riding the pressure wave in front of the bow for a while and then peeling away. Nobody on deck knows where the pod came from or where it is headed. Which beautiful thing near you might have a story you will never know?
Why it happens in nature
Dolphins breathe air consciously, so they rest one half of the brain at a time while the other half keeps them surfacing and alert, often with one eye open. They frequently ride the bow waves of moving boats, which saves them effort, and many species travel in pods whose membership changes over time.
What folk beliefs say
Italy
The Italians, a 1903 collection says, think that dolphins are angels cast out of heaven.
Source: Cora Linn Daniels; C. M. Stevans (eds.), Encyclopaedia of Superstitions, Folklore, and the Occult Sciences of the World, vol. 2 (1903), vol. 2, p. 1041. View the page
England
Dolphins love music, according to English folklore recorded in the same collection.
Source: Cora Linn Daniels; C. M. Stevans (eds.), Encyclopaedia of Superstitions, Folklore, and the Occult Sciences of the World, vol. 2 (1903), vol. 2, p. 621. View the page
United States (California)
Surfers at Huntington Beach, California, believe that when dolphins are seen during a session, sharks are probably not around, and they can expect a good day in the ocean.
Source: Daniel Kang (collector), Dolphins are "good vibes" (USC Digital Folklore Archive) (2012), folklore.usc.edu. View the page
To reflect on
Which everyday task do you have to do on purpose that others seem to manage without thinking?