No individual Tatley Creek exception appears in the Region 4 synopsis. Apply the regional defaults: no fishing Apr 1 to June 14, trout and char catch-and-release Nov 1 to Mar 31, and a single barbless hook required in all streams, all year. Confirm the current synopsis and in-season notices before fishing.

The creek sits at 50.36799, -115.82054, part of the same Columbia Valley cluster as marion creek and madias creek to the north and south. Local fish-observation data carries no direct records for Tatley Creek, so its fishing value is inferred rather than confirmed; it runs stream order 5 (well down the network toward river scale, on a scale that runs from 1 for a headwater trickle up to 6 or more for a full river), though a confirmed length is not on record. The channel-geometry numbers read small and steep: median width ~2.8 m (narrow) and median gradient ~18.63% (very steep), with a peak mean-annual discharge of ~0.219 m³/s (very low flow), consistent with a small, technical headwater tributary rather than a fishable mainstem reach.

There is nothing here to recommend as a destination yet. With zero direct fish observations and no guide who publishes a trip on it, the honest read is a regulation-and-access check rather than a fishery. The broader Columbia/Windermere system that Tatley feeds holds westslope cutthroat trout, bull trout, rainbow trout and kokanee, and marion creek just to the north has confirmed a 99.3%-pure westslope cutthroat population above its Highway 95 barrier, so nearby precedent for cutthroat presence exists. None of that has been confirmed on Tatley itself, and any fish found here should be treated as small-water resident or nursery fish until a survey says otherwise.

If future survey work confirms legal, fish-bearing water, the conservative small-stream box that fits the wider Marion/Madias/Tatley/Tukats cluster is Stimulator, Royal Wulff, Adams, Elk Hair Caddis, Hare's Ear, Prince Nymph and Pheasant Tail, with a small Woolly Bugger or sculpin pattern for any lower reach connected to the Columbia. Expected food in that scenario is small-stream fare: mayflies, caddisflies, sparse stoneflies, summer terrestrials and, where connected to the mainstem, sculpins, suckers and other baitfish and fry. None of this has been confirmed on Tatley itself; it is the surrounding cluster's pattern, not a creek-specific report.

No named road, trailhead, parking area or put-in has been confirmed for Tatley Creek. Whether any lower reaches cross private or reserve land has not been checked either, so treat access as an open question until confirmed on the ground.