If Great Lake is where Tasmanian trout fishing began, Arthurs Lake is where most visitors catch their first highland brown, and the reason is arithmetic. Inland Fisheries Service has run a postal survey of anglers here for twenty years and the lake has held at about two fish per angler per day the whole time, which on a wild, unstocked water of sixty-four square kilometres is a remarkable thing. The browns breed in the inflowing creeks and run half a kilo to a kilo, and brown trout is the only trout the lake has held since the 1960s. What makes Arthurs the confidence lake, though, is the mayfly. From mid-November the highland duns come up along the northern shore, established by early December and holding through February, mostly between late morning and mid-afternoon on the dull, humid days the plateau specialises in, and the run of shore from Jonah Bay to Cowpaddock Bay is where a visiting angler can stand on public ground and watch it happen. Before the duns, the fishing is wets and streamers along the drowned timber and rocky shores, and tailing fish in the margins at first light. The lake is a hydro storage that was two lakes and a marsh before the dam, it is pumped west into Great Lake to feed Poatina, its level moves a great deal, and its weather turns as fast as anywhere on the plateau. Bring a boat if you have one; the shore will do if you do not.
Water and habitat
A hydro-electric storage of sixty-four square kilometres made by damming the upper Lake River, which flooded two natural lakes, Blue Lake and Sand Lake, and the Morass Marsh between them. The water is pumped through to Great Lake to feed the Poatina power station, so the level varies a great deal, and IFS warns boaters of submerged rocks and dead trees when it is down. The shoreline is mixed: standing timber, weed beds, rocky and grassy shores, islands and scrub, which gives the lake a sheltered corner in most winds and is the structural reason it fishes more consistently than shallower Little Pine. The satellite record of the lake's wet surface since 1987 is drawn on this page in place of the gauge it does not have.
Fish and forage
Brown trout only, wild and self-sustaining, spawning in the inflowing creeks and running half a kilo to a kilo. IFS's twenty-year angler survey holds steady at about two fish per angler-day. The stocking record on this page is a single fish in 2025; the lake does not depend on it. The survey record of the fishery is drawn on this page.
The forage is the reason to come. The highland mayfly dun from November to February, with the best hatches along the shore from Jonah Bay to Cowpaddock Bay; gum beetle and ant falls on the wind in summer; heavy midge hatches in the calm; galaxias and mudeyes for the fish that feed deep. The deeper water through the main mayfly areas moderates the heat of high summer, which is why Arthurs keeps hatching when Little Pine has gone warm.
When to fish it
Early season, from the first Saturday in August, is wets and streamers along the shores and the drowned timber, and tailing fish in the margins in low light over the grassy shores. From mid-November the duns start, established by early December, mostly between late morning and mid-afternoon, and the dry fly takes over through February; a dull, humid, showery day is the day to be here, because the insects stay on the water. Bright days are for polaroiding the shallows when the water is clear, and for beetles on the wind. Autumn fishes quietly until the lake closes at the start of May.
The weather decides the day. IFS warns that Arthurs can turn suddenly rough at any time of year with little warning, and a boat angler should plan for it.
How to fish it
Before the duns show, a slowly retrieved brown nymph or a team of wets along the shore, and a Woolly Bugger or a streamer around the standing timber in the Morass, where the fish use the dead trees for cover. As fish begin bulging under the film, switch to an emerger, a Klinkhammer hanging its body through the surface. Once they are taking full duns, an upright dry in the size of the insect, a parachute Adams or a highland dun pattern, drifted without drag through the lane the fish is working. For sporadic rises from a boat, a short team with a weighted Pheasant Tail retrieved through the rise can beat waiting for the fish to show again. A five or six weight and a floating line, with an intermediate in the bag for the wet-fly days.
From the shore, Cowpaddock Bay in the mayfly season is the venue; Seven Pound Bay, Jonah Bay and Pumphouse Bay give good water in the northern bays. A boat lets you follow the weather and the hatch around the lake.
Access and safety
The B51 reaches the lake from Poatina to the north or the A5 to the south, and three formed roads reach its shore, with shacks scattered around it. IFS lists four launching areas, Jonah Bay, Pumphouse Bay, the Arthurs Dam and the western end of Morass Bay at Yangeena, and public campgrounds with a fee at Pumphouse Bay and Jonah Bay. Boating is restricted near the dam, the pump house and the spillway, and a five-knot limit applies north of the transmission lines across Cowpaddock Bay.
The lake is the hazard. Weather turns suddenly rough at any time of year, the level moves and exposes rocks and trees, and a thousand metres of altitude means snow in any month.
Regulations
Inland Fisheries Service states the rules for Arthurs Lake in its A to Z and the Inland Fishing Code: a minimum size, a generous bag for a lake fishery, all methods permitted, and a season from the first Saturday in August to the start of May. Every water flowing into the lake, and the lake within fifty metres of each inflow, is closed to fishing. An inland angling licence is required.
Take the numbers and the dates from the current Tasmanian Inland Fishing Code and the IFS A to Z page for the lake before you fish. They move, and this page does not carry them.