Peter Gray Parr Project

The Peter Gray Parr Project

Downeast Salmon Federation’s outreach facility and Peter Gray Hatchery on the banks of the East Machias River.

The Peter Gray Parr Project uses an enhanced rearing technique developed at the Kielder Hatchery on the River Tyne in northern England by the late Peter Gray to raise river-specific juvenile Atlantic salmon for population restoration purposes. The technique involves supplying the hatchery with unfiltered river water, using dark colored tanks to produce a naturally colored fish, increasing the flow in the tanks to create a more physically fit fish, stocking fish late in the fall, and stocking a lot of fish to saturate the river and jump-start the population.

The Parr Project takes place on the East Machias River. A small hatchery in East Machias is outfitted with all the necessary equipment to raise salmon eggs – initially produced at the Craig Brook National Fish Hatchery – into fall parr.

The Peter Gray Hatchery at EMARC

The Peter Gray Hatchery in East Machias

Hatching from eyed eggs to alevin typically occurs in the first part of March, with emergence of alevin from their substrate incubation boxes to their rearing tanks as fry in early May. The incubation boxes act as an artificial salmon redd in the hatchery, which helps the young salmon in this early developmental phase. The fry are larger when they emerge from the boxes and the fish emerge up out of the plastic media (just as they would emerge up out of the gravel in the river) when they are ready to feed.

The Project started off in 2012 with 52,000 parr going into the East Machias River. Since then, we have stocked approximately 500,000 Atlantic salmon parr into the East Machias. Reared using innovative techniques at the Peter Gray Hatchery, the Parr Project has received support from the North Atlantic Salmon Fund, the Atlantic Salmon Federation, and Peter Gray himself. In May of 2014, DSF’s hatchery was commemorated as “Peter Gray Hatchery,” honoring the late Peter Gray for his leadership and conservation efforts.

Alevin in the substrate of the alevin incubation boxes

Alevin in the substrate of the alevin incubation boxes at the Peter Gray Hatchery.

The salmon parr are stocked in the fall of their first year (designated “0+ parr”), once river water temperatures have dropped and the metabolism of the fish slows. The Parr Project hopes to demonstrate that this strategy can produce many more adult returns than fry stocking and achieve return rates equivalent to smolt stocking at a much lower cost. These parr will also spend more time in the river than stocked smolts which should make for superior survival behavior and natural selection.

Before the parr are stocked into the river, each one is marked with an adipose fin clip.  This distinguishes hatchery origin fish from wild fish during population assessments through electrofishing and smolt trapping. As it takes many weeks to clip all of the adipose fins, the community gets involved to volunteer their time at the hatchery.

Stocking 0+ parr raised at the Peter Gray Hatchery at EMARC as part of the Parr Project.

Stocking 0+ parr raised at DSF’s Peter Gray Hatchery as part of the Parr Project.

Without community involvement, help from our local students, and financial support from our dedicated friends, this project would not be possible! To learn more about this project and how you can help, please call Downeast Salmon Federation at (207) 255-0676 or email

Peter Gray Parr Project_Profile Sheet

Peter Gray Parr Project Booklet