A woman was excited to spot an otter at a Lancaster County lake.Melissa-Ann Kolessar, of Ephrata, snapped photos of the semi-aquatic mammal at Speedwell Forge Lake on March 15 and shared them with News 8.Video above: Wild Moments – River otters in the Susquehanna ValleyKolessar was with her husband, Drew Guthrie, when he first spotted the otter and pointed it out to her."The thrill and excitement of seeing that otter was just amazing. After it swam away, we turned to each other, laughed with excitement and gave each other a high-five," she said.She said she's seen otters before but never in Pennsylvania."I understand otters were all but extinct in PA but are making a comeback," she said.She's right about that.According to the Pennsylvania Game Commission, the resurgence of river otters in North America is one of the greatest success stories of modern wildlife conservation.The degradation of water quality, human encroachment and unregulated harvest led to a 75% decline in otter populations.Otter populations were also vastly reduced in Pennsylvania. Beginning in the 1970s, restoration efforts here and in neighboring states allowed for significant expansion.Otter populations are now increasing or stable in the commonwealth.The most dense otter populations are in northwestern and northeastern counties, but it's not uncommon to see them elsewhere.In Pennsylvania, otters live in every major river system and are absent only in watersheds with significant water quality issues.Kolessar said she later ran into a woman who walks her dog around the lake each morning. The woman said she often sees the otter sitting on the stones behind the spillway. The Game Commission confirmed that otters are regularly sighted near Speedwell Forge Lake.About ottersFast, graceful swimmersAccording to the Game Commission, an otter is the most adept in water of all the land mammals.It can travel underwater a quarter-mile without coming up for air. It can also dive 35 to 50 feet and stay submerged up to four minutes.An otter's top swimming speed is about 7 miles per hour.Where they denOtters den on the edges of lakes, rivers or streams. Occasionally, their dens will be on islands or patches of high ground in marshes.Dens might be excavations under tree roots or rock piles, abandoned beaver, muskrat or woodchuck burrows, or unused beaver lodges.A typical den has an underwater entrance hole, a living space above water level and several air or exit-entry holes to dry ground.What they eatOtters obtain most of their food from the water.Fish – including minnows, sunfish, suckers, carp and trout – are favorites.Otters may also eat frogs, turtles, snails, mussels, crayfish, snakes and snake eggs, worms, insects, aquatic plants and roots.On occasion, otters will consume birds and small mammals.Share your photos and videosWe're always on the lookout for viewer photos and videos.Share them with us in any of the following ways. We may use some of them on air or online.DIRECT UPLOAD: There is a form here to upload photos or video.EMAIL: Just send to news8@wgal.com.JOIN OUR FACEBOOK GROUP: Our uLocal Facebook group is here.