I would like to add to my previous info.........you will be close to the Fern Lake trailhead and the Bear Lake trailhead, both of which access some high lakes that hold good fishing. The hike to Fern Lake is fairly easy and short....about 3.5 miles one way I believe....Odessa is another mile up the trail. Both Fern and Odessa hold solid populations of greenbacks (cutthroat variety).
The Bear Lake trailhead is even better. The hike(s) to the Loch and Mills Lake are very easy. The Loch is especially scenic and has great fishing. If you can make it up the trail, Lake of Glass and Sky Pond are arguably the most scenic areas of the Park......and both lakes have good fishing. The views at these lakes are jaw-dropping. The Loch and Lake of Glass hold nice, little greenbacks and Sky Pond is loaded with brook trout.
There probably will be some lingering snow on the trails above 10K feet so be prepared for wet and muddy trails. But the trails should be very passable. The shores are heavily timbered at these lakes so pack in some waders or hippers.
But again, I think there is road construction on the way to the Bear Lake TH, so just check with the rangers once you're in the park. BTW, the rangers at the park will be your best source of up to date info. If you ask a ranger something and he or she doesn't know, they will immediately get on the radio and find out.......
Fishing - Rocky Mountain National Park