Learn Spanish (Latin America): Al caminar hacia la popa, él rompió el sedal y la caña. - Upon walking toward the stern, he broke the fishing line and the fishing rod.

The structure al + infinitive is a very common shortcut in Spanish to say "upon doing [action]" or "while doing [action]". It replaces a full conjugated clause like cuando caminaba (when he was walking). It works perfectly here because the same person is doing both actions: walking and breaking the gear.

Since Spanish usually drops subject pronouns, why include él before rompió?

Because the first part of the sentence (Al caminar...) uses an infinitive, there is no conjugated verb there to tell us who was walking. Including él in the main clause makes it crystal clear that "he" is the subject of both actions, preventing any ambiguity if other people were mentioned in the broader conversation.

Why use hacia la popa (toward the stern) instead of a la popa or hasta la popa?

Hacia emphasizes the direction of his movement ("toward"). Using a would simply mean "to" the stern, and hasta would mean "as far as" the stern. Hacia paints a clearer picture that the accident happened while he was in motion in that general direction, even if he hadn't reached his destination yet.

Caña usually means "cane" or "reed". How do we know it means "fishing rod" here?