One Last Glimpse of Mexico – And Into a Whole New World

More that 300 miles off the coast of mainland Mexico, the uninhabited Islas Revillagigedo offered our well-worn Mexican courtesy flag* one last opportunity for service as we sailed by.

This remote volcanic archipelago of islands is a marine reserve which is part of Mexico’s National Park system. In 2017, it was designated a UNESCO World Heritage Site, because of the rich biodiversity of the flora and fauna. Particularly, the aquatic life found in the surrounding waters, including giant manta rays, various whale species, and a wide assortment of sharks. Permits are required to visit, and the diving is reported to be spectacular.

The conditions were relatively calm, so we decided to test our new hydrophone a few miles offshore of Isla San Benedicto. It’s designed for listening to and recording the sounds made by whales, dolphins and other underwater creatures. Once the headsail was furled, we headed the boat into the wind to stop our forward momentum, then lowered the unit’s submersible microphone into the water. 

We were hoping to hear the songs of Humpback whales who feed and give birth in these nutrient-rich waters during the winter months. The sensitive microphone did pick up the high-pitched sounds of what we believe were dolphins in the distance. We also heard some very faint sounds that were lower and longer in duration.

All three of us share a fascination for whales. Sharon, is particularly passionate, and has served on the Board of the Canadian Whale Institute for many years. Shawn’s daughter is a marine biologist. But none of us have any experience using the hydrophone. This first test certainly helped motivate our desire to become more skilled at eavesdropping on the creatures who inhabit the vastness below the surface on which we float.

*Courtesy flags – as a show of respect, foreign vessels are expected to fly a small flag of the country they are visiting throughout their stay. It’s customary for a courtesy flag to be flown on the starboard side at a height above the visiting vessel’s own national flag.

– Bill