The Arctic Char is one of the rarest and hardest to catch fish in the lower 48 states and even knowing where they may be doesn't make it much easier to catch. Having only a native range originally of Vermont, New Hampshire, and Maine made them rare from the beginning, and as far as my research has discovered, only Maine has a native population remaining. There are only about a dozen bodies of water in Maine that still maintain a native population of this beautiful fish. Knowing where those waters are and how to get to them is half the battle.
I have been lucky enough to have spent a great deal of time fishing one of the best (if not the best) pond in Maine for catch rates and size for arctic char. I have been successful in landing for myself and guiding many arctic char to the net in the 18" - 23" range with some of them being such a bright orange color it will make one think it isn't real!
These fish sit in deep cold water in these remote ponds that are often fly fishing only. I have come to find that they feed generally in the 15' - 25' depth and anything you may see deeper than that just won't take a fly. The most difficult aspect of this is how to get a fly down to that depth range with an effective presentation. Heavy full sink line is a must with the ability to cast it a solid distance, at least 50', hopefully more. Have to let it sink for a good 20 seconds give or take, and start stripping it back in. It can be a grind chasing this elusive fish long casting heavy line from a canoe all day and stripping, it is tiring! But when you feel a freight train smash your streamer on the other end and the long fight dredging an 18" fish up from 20' down ensues, it is well worth the effort!
They often like to nose down and dig straight to the bottom, putting immense pressure on the rod and line and even your arms. Having a solid 6 weight rod with good 4x leader/tippet is highly recommended. I have had good success with hornbergs, black nose dace, small grey ghost, BTO's, and smelt patterns with pink.
These fish can be caught nearly anytime during the open water season but to see them in their true orange spawning colors, late September is the ticket. I spend the last couple weeks of each September guiding for bluebacks and this year coming up I will be chasing them the last three weekends of September. It is at the top of my list for fish to chase and when someone lands one of these beauties the feeling is difficult to describe!