Magic is extremely common, it is essentially part of the dna of each race. Each race has magical power that allows them to better dominate their native environment. One race can shapeshift, other can create and control fire/heat, etc...
One of these races evolved with a sea-faring lifestyle. They are spread arround the world and vary greatly in culture and traditions due to this geographic distribution, but they are regarded as the best sailors wherever they are found. Naturally their innate magic plays a role in their naval dominance,but what role?
I've been thinking about this for quite a while, but I still have not found a satisfatory solution: What kind of magic would aid sailing the most? I came up with a few candidates, but I am probably forgetting some obviously better options. I am not interested in creating overly powered individuals, but racial advantages, so if magic is too powerful, it might need many individuals to power it.
Precognition: being able to predict the near future, or at least what it is likely to happen if everything stays the same (and they hardly do). Precognition is particularly useful to predict the weather, as there is few things that would stop or cause a storm to happen out of nowhere, giving them a nice strategic edge.
Weatherkynesis: a more straight foward way of influencing the travel. Due to my own rule, it would take many of them to make grand feats, e.g. it would take a fleet to create or dismiss a sea storm. Not my favorite as it do not benefit individual sailors and its overpower (if you try to outnaval them, they can just send a storm to destroy the enemy fleet).
Hydrokynesis: the most intuitive of the bunch. They might not be better them others at predicting the weather or avoiding pirates and sea-monsters, but once they get caught in these situations they are able to handle themselves better than most, being able to break the most dangerous waves, extract drinkable water from the sea and outrun other ships of similar size.