In my book series, there is this planet called Ryu 108. Ryu 108 consists of two continents: Bjørnholm, which is heavily forested and bears a strong resemblance to southern Norway or southern Sweden, and Hrafnfjell, which is severely glaciated and volcanic, bearing a strong resemblance to Iceland. Both continents are inhabited by the 108er Kingdom, a planet-wide kingdom of what are essentially viking-age norsemen. However, a vast ocean separates the two continents, and in this ocean lurk hundreds of thousands of krakens.
Krakens are underwater beasts that resemble the giant squids of our world, except they are roughly triple the size of them in all dimensions. In addition to this, the suckers on kraken tentacles inject a poison into their prey that almost instantly renders them unconscious.
To make matters worse, dragons called Wyverns nest on small, rocky islands scattered throughout the sea. During the day, they are usually content to stay on land guarding their eggs, but at night, they raid the coastlines for prey to take back to their nests, much to the annoyance of mammoth and cattle ranchers near the coast. There are 5 different variants of wyvern: fire (which breathes fire), lightning (which breathes bolts of lightning), water (which breathes highly pressurized, boiling hot water and is the only wyvern that can swim and breathe underwater as well as on land), poison (which breathes gusts of poison gas), and ice (which breathes liquid nitrogen). While used to going onto land for meals, wyverns (especially water wyverns) have also been known to pluck people right off their longships and bring them back to their nests to consume. Wyverns can be anywhere from 30-40 feet long (with a 10-18-foot tail), have 2 legs and 2 wings, weigh 1,500-2,500 lbs, and have a top speed of around 70 mph.
Now here is my question: How would the 108er Kingdom deal with these creatures to maintain contact with and conduct trade with its other half across this treacherous sea?