Whale watching in April: Is it better in Mirissa or Trincomalee?

Mid-April is actually the transition period between the two coasts. In Mirissa, the season usually runs from November to April, while Trincomalee picks up from May to October. If you are going in the first half of April, Mirissa is still your best bet for high sighting probabilities. The sea is typically very calm right before the monsoon shifts, which makes for a much more comfortable boat ride. However, keep in mind that blue whale sightings have been a bit more unpredictable lately, so manage your expectations.

I agree with staying south for April. Trincomalee can be hit or miss that early in the month because the whales are still migrating around the island. For an ethical experience in Mirissa, I highly recommend Raja and the Whales. They are a family-run business and were among the first to follow international guidelines. They actually keep a respectful distance and even contribute to research by logging sightings. They usually provide breakfast and ginger tea for seasickness too which is a nice touch for a long morning on the water.