Effective Communication While Kayaking (or SUP)
The outdoor environment can be extremely challenging. The noise from the wind and waves can drown out many sounds. The distance you are from your paddling partners can also make verbal communication impossible. I have been in rolling seas where I lost sight of my partner when he or she was on the other side of the wave.
There are many methods one can use to signal or interact with the rest of the group or the outside world. In our present electronic age we have cell phones, short distance walkie-talkie's (hand held radios), VHF radios, emergency locating devices, and signal lights. We can also use flares, smoke, whistles, dyes, horns, ribbons, signal flags, mirrors, paddles, our arms and hands.
Regardless of the method of communication you choose to use, you need to know if the person receiving the message knows what you are sending. There needs to be a common understanding of the signals and messages. You also need to know how effective or ineffective some of the above communication methods are in the real world.
I remember a windy return trip from a compass run off of Martha's Vineyard. I asked two of the folks at the tail end of the group to capsize and signal the front of the group for assistance. We were going into a head wind. The two in the water only had whistles. They didn't even try shouting because they knew the paddlers in front were too far away. However, their amazement was apparent when the group did not hear their whistles. The distance was about 200 yards.
We had to send a paddler ahead to get closer to the group so they could hear a whistle. Due to the wind, those in front never heard the initial whistles. The fact that none of the lead group never turned around on regular basis to check on those behind is a discussion topic for another time. I often tell groups to test their whistles on calm days and windy days to see how far their whistles carry with and against the wind.