“You’ll see lots of eagles,” Eggman Decoster promised when he invited my wife, Nancy, and me for a paddle trip on the Sebasticook River. That was all the incentive we needed to join him and others for a 6-mile outing between Benton Falls and the Kennebec River in Winslow.

Eagles haven’t always been plentiful on the Sebasticook. Two dam removals changed that dramatically. In 2008, the Fort Halifax Dam near the mouth of the river in Winslow was breached. That coupled with the earlier removal of Edwards Dam on the Kennebec River in Augusta has resulted in free-flowing rivers between Benton Falls Dam and the ocean in Popham.

The dam removals facilitated the return of native sea-run fish to include alewives, striped bass, salmon, sturgeon and chad. As they migrate upriver in the spring, fish-eating birds, particularly eagles, follow them.

Finding a full day of good weather in the month of May was a daunting task. After two postponements due to inclement weather, we finally identified an acceptable but imperfect opportunity for our avian river outing.

Seven of us met at the takeout in Fort Halifax Park on a cloudy, cool, windy day. Situated where the Sebasticook joins the Kennebec River in Winslow, the scenic park has ample parking and offers opportunities for walks, boating and picnics. A downside: The physical takeout is a long carry to the parking area.

We left a shuttle vehicle and drove a few miles north on Garland Road to Brimstone Road on the left. This narrow road leads to a parking area at the foot of Benton Falls Dam. A lengthy portage trail on river left provides access to an undeveloped put-in in a pool above some rapids.

Two tandem canoes and three solo kayaks launched in quick water. Since some of us were paddling flatwater boats; our first challenge was navigating through a few Class I/II rapids. Everyone had problem-free descents.

Once the rapids were completed, we caught eddies to regroup. Eggman’s predictions were quickly confirmed. We were amazed to see exceptionally large numbers of eagles circling above and perched in tree branches overhanging the river.

The sheer numbers of the impressive birds was remarkable. Maine Marine Resources reports a higher concentration of eagles in this area than any other location in the continental United States. Paddlers in our group counted 26 eagles at one time in just one area. Overall, the estimated count was about 75.

After the early rapids, we benefited from a strong current for the remainder of our trip. Although we had to cope with powerful winds, for the most part, they were tailwinds that helped propel us along.

As we progressed downriver, eagles were perpetual traveling companions. However, they weren’t the only winged inhabitants we met. A multitude of Canada geese, ducks, cormorants, ospreys and more joined us. Most were presumably feeding on the abundant fish supply.

Since it was prime migration season for alewives, we expected to find huge schools of the river herring. However, they were largely absent during our trip. A biologist in our group familiar with their habits observed that they don’t move much in cold temperatures. Regardless, the obviously very well-fed eagles must be proficient at locating stationary alewives or they’re feeding on other fish species.

About a mile from downtown Winslow, Outlet Stream enters on the left. Until recently, over 200 years had elapsed since alewives were able to reach China Lake due to dams on the stream. With the removal or modification of six dams, hundreds of thousands of alewives now migrate 7 miles upstream to the lake each year. The eagle population has exploded on the lake and stream.

We paddled up Outlet Stream for a short distance. The narrow waterway appeared navigable but no alewives were seen. Some of us contemplated a descent from China Lake when the water level is higher.

Below the stream, the water velocity increased and the river narrowed causing erratic currents that required careful negotiation. Soon after, we passed the remains of the Fort Halifax Dam in Winslow before arriving at the takeout in Fort Halifax Park.

Ron Chase resides in Topsham. His latest book, “Maine Al Fresco: The Fifty Finest Outdoor Adventures in Maine” is available at northcountrypress.com/maine-al-fresco or in bookstores and through online retailers. His previous books are “The Great Mars Hill Bank Robbery” and “Mountains for Mortals — New England.” Visit his website at ronchaseoutdoors.com or he can be reached at ronchaseoutdoors@comcast.net.