It’s a spring day in northern Sweden, just 100km (62 miles) below the Arctic Circle. I tuck my sound gear into my backpack, clip into my cross-country skis and glide out on to a frozen lake, looking for a small ice-fishing hole.
It’s a quiet day, with no snowmobiles or other skiers about. Conditions are perfect for the fishing I hope to do: not for dinner, but for sounds.
I find the hole, kneel next to it and slowly feed a hydrophone – a waterproof microphone attached to a long cable – down into the slushy water. Then I press record, cover up my gear and ski away.
