Subscribe & stay up-to-date with ASF

In The Field

Maine Salmon Rivers in a Year of Covid-19 Pandemic


Featured image
A 2020 large Atlantic salmon being measured at Milford Fish lift. Photo Maine Department of Marine Resources
The 2020 US Fish and Wildlife Service Plan for Maine salmon is unlike anything that has gone before.

With Covid-19 working rules in place, all of the salmon that reached the Milford Fish Lift or Orono Dam were allowed to proceed upstream until June 15.

By June 20, this included 815 Atlantic salmon allowed to proceed upstream, and 103 taken to Craig Brook as broodstock since the June 15 beginning of collection.

Featured image
Atlantic salmon held in tanks at Craig Brook National Fish Hatchery in East Orland, Maine. Tom Moffatt/ASF
In past years Fish and Wildlife aimed to collect about 650 Atlantic salmon for broodstock, and they would take nearly all of them early in the run. In more recent years, they have tried to space out the collection over a greater time period in order to better represent the overall run.

So, over the last decade, we’ve seen as many as 2,500 adults allowed to go upriver to spawn, as in 2011, to only a small handful, as in 2014 when only 261 adults were captured and nearly all went to the hatchery.

This year, USFWS is planning to collect 400 adults: 50 grilse, 150 males, and 200 females.

They are only taking a maximum of 30 per day, and are only collecting Monday through Thursday, plus they are taking all fish before 11 am to reduce the potential for harming the fish during the warmest part of the day

Featured image
Of the many Atlantic salmon allowed to proceed upstream from the Milford Dam in 2020, some certainly will use this Howland Bypass, a naturalized channel for salmon to proceed upstream into the Piscataquis River, the major "west" branch of the Penobscot River. Tom Moffatt/ASF
This is all more to do with COVID protocols than with any strategic broodstock management and collection goal since the number of fish that go to the hatchery is going to be far less than is needed. Another 90 fish are being tagged and released back below Milford for fish passage effectiveness testing. All of those fish that get recaptured at Milford will be released upstream and followed as they pass through the other dam sites.

As of June 20, the intense early summer heat has meant water temperatures have reached 79 F., requiring the greatest care in handling the salmon.

The Penobscot returns of Atlantic salmon has always been complex.

The Penobscot always had a fall run of salmon and several distinct runs in different tributaries of the river. Historically, at least in the latter half of the 20th century, the midpoint of the run was around July 4.

Featured image
The Mattawamkeag is a massive set of tributary spawning streams and a large mainstream river to the east of Mt. Katahdin. Maranda Nemeth/ASF
Numbers in the fall have represented a smaller percentage of the overall run, and now the mid-point of the run appears to be about 10 to 12 days earlier than it was in the latter half of the 20th century.

Ditto the smolt out-migration. Those runs have shifted earlier in the Penobscot and other Maine rivers in recent decades. The prevailing theory is that the fish are adapting to the rapidly changing climate and flow conditions in our rivers. This makes it all the more important for Maine wild Atlantic salmon to get to the colder headwaters in the Penobscot and other watersheds as rapidly as possible.

Obviously it remains to be seen the total number of Atlantic salmon that will be taken to Craig Brook for broodstock this year. The 2020 Covid-19 year continues to require adjustments, and just perhaps a change in overall views on salmon migration in today’s Maine rivers.

Featured image
Removal of the two lowest dams that blocked the Penobscot River has allowed the ongoing renewal of this river and its Atlantic salmon runs. This is Great Works Dam, first to be removed. Photo Penobscot River Restoration Project
Featured image
John Burrows undertaking habitat surveys in the Sandy River in Maine.