Lure of fishing Canada and Alaska

Casting a dry fly on Surprise Lake, Atlin, northern British Columbia.

One-fifth of tourists visiting Alaska, British Columbia and the Yukon Territory plan their trip around fishing. It's popular with the locals too - of the 4.6 million BC residents, about half go fishing, compared with about a third of us in WA.

And indeed there are plenty of fish and plenty of places to catch them. BC alone has more than 200,000 lakes, 750,000km of rivers and 24 sport fish species, including rainbow, cut-throat and steelhead trout, char (brook, lake, bull and Dolly Varden), kokanee (landlocked salmon), sturgeon, pike, walleye (like a cross between a pike and a redfin perch), bass, Arctic grayling and five species of Pacific salmon: chinook (the biggest, reaching 35kg), chum, coho, sockeye and pinks, which travel up the rivers at different times between June and December.

So if you want to fish BC you're really spoilt for choice. But you do pay for the privilege - a tourist daily licence costs $20 and one for eight days costs $50.

Alaska, meanwhile, has three million lakes, 3000 rivers and a similar number of fish species to BC. Licence fees for freshwater fishing in Alaska are similar to those in BC, costing $20 a day and $55 for a week. So your greatest challenge will be deciding where to get started - BC or Alaska.

With time and a bit of planning, you can fish both. Fly into Vancouver, acclimatise by doing some fishing in the excellent rivers and lakes in the Coastal Range, add the splendid Birkenhead River near Pemberton for rainbow and cut-throat trout, say hello to the locals at Whistler's ski resort which also has some fine trout lakes nearby and then fly north to Whitehorse, capital of the Yukon Territory.

The mighty Yukon River is 3200km long, nearly the distance from Perth to Melbourne. It flows through Whitehorse and is home to a variety of fish. When it reaches the city it is just 180km from its source in the Llewellyn Glacier, and already 150m wide, deep and muscular. It flows through the Yukon Territory and crosses the entire width of Alaska before draining into the Bering Sea.

Hire a car in Whitehorse and it's a drive of just a few hours to the best fishing in both northern BC and Alaska. Start in Whitehorse, which is surrounded by lakes and has the mighty Yukon River flowing through it.

In these waters you'll catch enormous lake trout, equally big northern pike, as well as freshwater salmon and grayling.

Drive south to Atlin and you'll catch all of the above, as well as rainbow trout, grayling and Arctic char, a species similar to lake trout.

Drive south-west to Skagway or Haines and you can add three salmon species - chinook, coho and sockeye - to the list, plus Dolly Varden, a very pretty fish named after a character in Dickens' novel Barnaby Rudge who wore brightly patterned clothes. Dollies, as they're affectionately known, are a type of char but their habits and life cycle are more similar to salmon.

Salmon and all the various species of char and grayling readily take a fly. This is important to fly fishermen, who set themselves apart from the users of bait or spinners.

The notion is that fly fishing requires more art and more skill to present a nearly weightless artificial fly, tied to look like the real thing, while using a special lightweight rod and line to catch a fish. It's considered more sporting (pause for the generalist freshwater angler to snort with derision) but also, having delicacy, it can be the only way to catch some shy fish in gin-clear water. Finding the correct fly is important because it has to match any flies ambient to the water and the time of year you're fishing. Over hundreds of years, fly fishermen have invented flies that look like particular natural flies, giving them arcane names such as royal coachman, greenwells glory or woolly bugger.

In early summer, if you're after dollies, char or trout, bring plenty of nymphs and woolly buggers. Later in summer when salmon are spawning, fish with patterns which imitate pink salmon roe.

The grayling is a hard-fighting fish for its size and as delicious to eat as trout or salmon. It readily takes a dry fly and inhabits mostly the cooler waters of the north. One of the best spots for these fish is Pine Creek, near Atlin, where it flows out from Surprise Lake - an opinion confirmed by many other anglers. The other contender for the best grayling fishing is a stretch on the Yukon River just downstream from Whitehorse.

Salmon of all types readily take a fly as well as lures and spinners. In many rivers in late summer or autumn, such as the Chilkoot and Chilkat rivers near Haines in Alaska, if you're wading the river to fish, the salmon spent after spawning can be so plentiful you have to be careful where you put your feet. You'll also find yourself sharing the river with several grizzlies - though being as intent on fishing as you, they very rarely bother anglers.

For the really bold fisherman, BC is home to the white sturgeon. These are modern-day dinosaurs, having been about for 100 million years. They are recognised for their fighting abilities and have been known to reach 600kg and a length of 6m in their 100-year life span. A protected species, sturgeon must be released unharmed, but hooking one is likened to battling a cross between a marlin and a freight train.

Interestingly, a BC survey of angler motivation found most tourists fish to enjoy nature and relax, with actually catching or eating big fish way down the scale. Hmmm. Cue Henry David Thoreau quote: "Many men go fishing all of their lives without knowing it is not fish they are after."