adipose fin

Over 10,000 Coho Fry Marked at Hoy Creek Hatchery

Fisheries and Oceans Canada supported Hoy Creek Hatchery in Coquitlam for our annual fin clip on June 20. The coho salmon are approximately 3 months old.

The adipose fin is removed and is a soft, fleshy fin found on the top of the salmon, on the back behind the dorsal fin and just forward of the caudal fin. This marking of our coho supports:

  • Stock assessment for when salmon return to spawn, the clipped fins allow hatcheries and stream keepers to monitor their return.

  • Selective fisheries - in certain regions and sub-areas, a marked fishery is permitted for retention of the coho.

  • The procedure also allows for a manual fish count, whereas previously only weight sample counts took place.

The operation was overseen by DFO fisheries community advisor, Isaac Nelson and Hoy Creek Hatchery manager, Tyler Storgaard. Volunteers of the Hoy/Scott Watershed Society assisted.

First, the fish are anesthetized in small batches. Once in the solution, they become sleepy within minutes. The volunteers stand ready around a table equipped with a trough with flowing water and beds of water for the fish to lay in. Volunteers work quickly and very carefully to clip fins with disinfected surgical scissors before they wake up, which is within about a minute. Fish are put into the outside trough and end up in the bucket at the end of the table. They are returned to the hatchery to recover.

The fish will soon be transferred from the hatchery Capilano trough room and will live in the rearing pond until Salmon Leave Home in May 2023. Fish from this brood could then return in about 2.5–3 years.

Thanks to all those who helped out this year!

Hoy-Scott Watershed Society (HSWS) is a volunteer-run non-profit society that operates a small salmon hatchery beside Hoy Creek and conducts a salmon enhancement program in partnership with the City of Coquitlam, and with technical expertise from the Department of Fisheries and Oceans Canada. The group stewards the Hoy and Scott Watersheds, promoting public awareness and education, and is involved in watershed habitat restoration and preservation. 

10,000 Coho Marked at Hoy Creek Hatchery

HSWS student volunteer, Ririka works alongside DFO members on her first fin-clip.

On June 10 our annual adipose fin clipping session took place at Hoy Creek Hatchery. Over 10,000 Coho fry, approximately 6 months old had their adipose fin removed to identify them as 'hatchery fish.'

Led by hatchery manager Tyler Storgaard, the procedure is overseen by the Department of Fisheries and Oceans Canada who had three members on-site assisting. The adipose fin, located at the top back of the salmon is removed after the fish have been sedated. It's a fast process and many careful hands make light work.

The clipping station set up outside the Hoy Creek Hatchery on June 10, 2021.

The markings also help the society identify the hatchery fish during returns in the fall.

Thanks to Hoy-Scott Watershed volunteers who put in the time to assist with this exercise.

The fish will be moved to the outdoor rearing pond in the coming days and will remain there until May of 2022.

Sedation area

Annual adipose fin-clip held at Hoy Creek Hatchery

Hatchery manager Rodney Lee demos the adipose fin-clipping procedure as Tyler Thibault of the DFO looks on (center). 

Hatchery manager Rodney Lee demos the adipose fin-clipping procedure as Tyler Thibault of the DFO looks on (center). 

Close to 6000 coho salmon had their adipose fin clipped as part of a Department of Fisheries Canada encouraged exercise at Hoy Creek Hatchery in Coquitlam on June 20.  The salmon are approximately 6 months old. The adipose fin is a soft, fleshy fin found on the top of the salmon, on the back behind the dorsal fin and just forward of the caudal fin.

Although it's not mandatory, the DFO strongly advise hatcheries to clip the adipose fins for several reasons:

  • When salmon return to spawn, the clipped fins allow hatcheries to monitor their return
  • Most sports fisherman know that clipped coho can be kept, while wild coho must be returned
  • Clipped fish returns help DFO assess overall returns, helping to ensure the wild salmon are more dominant.
  • The procedure also allows for a manual fish count, whereas previously only weight sample counts took place. 
Everyone counts the fish they clip. Close to 6000 fish were processed. 

Everyone counts the fish they clip. Close to 6000 fish were processed. 

Overseen by DFO fisheries technician, Tyler Thibault, a group of about ten Hoy-Scott Watershed Society volunteers came out to help in the operation.  Hatchery manager, Rodney Lee explained the procedure to a few people who were clipping their first time. 

First, the fish are anesthetized in small batches. Once in the solution, they become sleepy within minutes. The volunteers stand ready around a table equipped with a trough with flowing water and beds of water for the fish to lay in. Volunteers work quickly and very carefully to clip fins with disinfected surgical scissors before they wake up, which is within about a minute. Fish are put into the outside trough and end up in the bucket at the end of the table. They are returned to the hatchery to recover. 

Fin clipping volunteers of Hoy-Scott Watershed Society with Tyler Thibault of the DFO at Hoy Creek Hatchery. (Missing: Nathen Blower)

Fin clipping volunteers of Hoy-Scott Watershed Society with Tyler Thibault of the DFO at Hoy Creek Hatchery. (Missing: Nathen Blower)

The fish will soon be transferred from the hatchery Capilano trough room, and will live in the rearing pond until Salmon Leave Home in May 2019. Once they are released, they stay about a year in the stream making their way to the ocean. Fish from this brood could then return in about 2.5 years.

Thanks to all those who helped out this year!

(Watch our VIDEO below).

Hoy-Scott Watershed Society (HSWS) is a volunteer-run non-profit society that operates a small salmon hatchery beside Hoy Creek and conducts a salmon enhancement program in partnership with the City of Coquitlam, and with technical expertise from the Department of Fisheries and Oceans Canada. The group stewards the Hoy and Scott Watersheds, promoting public awareness and education, and is involved in watershed habitat restoration and preservation. 

Fourth annual fin clipping exercise at Hoy Creek Hatchery

Volunteers carefully snip the adipose fin off a sedated coho fry

Volunteers carefully snip the adipose fin off a sedated coho fry

On June 15, 2017 we performed our fourth fin clipping exercise at Hoy Creek Hatchery for our coho salmon fry.

The adipose fin is removed after the fish are sedated. It's a fast process and many careful hands make light work.

The entire procedure is overseen by the Department of Fisheries and Oceans. All fry recovered expect one of approximately 5500 fishmarked.  The markings help the society identify hatchery fish during returns in the fall.

Thanks to Hoy-Scott Watershed members who provided the photos seen here.

Many hands make light and fast work! Hoy-Scott Watershed Volunteers during our fourth annual fin-clipping exercise

Many hands make light and fast work! Hoy-Scott Watershed Volunteers during our fourth annual fin-clipping exercise

Sedated coho fry. 

Sedated coho fry.