how did dagur hear rumors about the dragon riders

Dagur heard the rumors through word-of-mouth before confronting Hiccup, and the story he picked up was that Hiccup and the others were training dragons. In the episode context, Dagur specifically confronts Hiccup about rumors of the Red Death and dragon training, but Hiccup denies them.

Quick Scoop

What Dagur seems to have heard was not a detailed “official report,” but a rumor network spreading around the archipelago. That kind of information would fit the world of the series, where chiefs, traders, and travelers pass along stories quickly, especially about something as unusual as dragon training.

What likely happened

• Dagur learned that the Dragon Riders were not just fighting dragons, but working with them.
• The rumor reached him before he had direct proof.
• He then confronted Hiccup to test whether the story was true.

In context

The important part is that Dagur did not discover it through a clean, confirmed source. He heard it as a rumor and reacted to it aggressively, which is consistent with how his character usually operates.

If you want, I can also explain this by episode or give the full scene context in a spoiler-light way.