Tiber Reservoir is not set to be the next destination spot for anglers seeking trout on a Montana fly fishing trip. However, it is a good lake for warm water fishing and general recreational boating.

Located out in the middle of the prairie in north central Montana, Tiber Reservoir, formed by the Tiber Dam on the Marias River, is quite isolated. It is also quite large—spanning more than 14,800 acres when at full pool.

Despite its remote location, Tiber Reservoir sees a fair amount of use from the local population, with local being considered anywhere within a hundred mile radius. During a nice summer weekend, there are often dozens of powerboats and water-skiers out aimlessly cruising the lake.

For trout fishing, Tiber Reservoir is not highly recommended. Instead, Tiber Reservoir is known for its solid warmwater fishing. The main fish species in Tiber include pike, walleye, perch, catfish, lake trout and panfish.

The Montana FWP does stock Tiber Reservoir with rainbow trout. Trout, both rainbows and browns, are typically found near the inlet of the Marias River.

Tiber Reservoir is quite large and is often very windy. As a result, a motorboat of one kind of another is needed to sucesfully fish the lake.

Access to Tiber Reservoir is excellent. Several designated access sites exist around Tiber Dam. It is also very easy to travel away from the designated access sites along many parts of the lake boundary.

It’s along way to anywhere from Tiber Reservoir, so anyone venturing out to Tiber Reservoir should plan on bringing their RV or tent. Several camping areas around Tiber Dam exist that provide decent facilities.

Important Note – Due to the discovery of zebra mussels in Tiber Reservoir, Montana FWP now requires inspection of all boats leaving the reservoir. Check the latest fishing regulations for the locations and hours of the inspection stations.

More information about AIS and watercraft inspections at MT. Gov