There was a day back in late October when my eight went out at 5:15am and it took our coach 20 minutes to find us because he couldn’t see us in the dark. I had a black coat and rain pants on, our boat is a black Resolute, and the batteries on the bow/stern lights were fading so the lights were pretty dim, which made us practically invisible to him.
Although ultimately it wasn’t a huge deal it’s still a safety risk to be on the water and not visible to other people. I have a high-vis running jacket that I started wearing over my normal jacket and our bow-seat had a clip-on LED light that she’d put on the back of her hat. A lot of the scullers I see will also put LED lights on the back of their hats, along with wearing a runner’s vest or putting a strip of reflective tape on the back of their jackets.
#1 rule of coxing – better safe than sorry! Take precautions when you’re out on the water, even if it’s light when you go out or when you come in. If it’s going to be dark at any point during practice, make sure you have lights on your boat and are wearing something that will increase your visibility to other rowers, coxswains, and coaches who are out at the same time as you.