Cypress Island Atlantic salmon pen break

On August 19, 2017, a net pen break resulted in the accidental release of hundreds of thousands of farmed non-native Atlantic salmon near Cypress Island, Skagit County, Washington into the wild. The salmon farm was run by Cooke Aquaculture Pacific, LLC.^[1] According to the Washington State Department of Natural Resources, the inadequate cleaning of biofouling on the net pens containing the farmed salmon was likely the primary cause for the pen break.^[2]

Background

Prior to the incident, Washington was the only U.S. state on the Pacific coast where Atlantic salmon was farmed.^[3] Atlantic salmon are favored by salmon farmers since their domestication process is much further along; farmed Atlantic salmon have been selected for faster growth, higher tolerance to disease, and greater docility.^[4]

The net pen in question was managed by Cooke Aquaculture, a Canadian company. Based in New Brunswick, the Canadian company is one of the largest aquaculture companies in the world. It took over the Cypress Island aquafarms in 2016.^[5]

The pen that was breached was pen #2, a ten-cage salmon pen that contained 305,000 fish.^[2] Pen #2 was placed in 2001.^[6] The salmon pen was anchored in Deepwater Bay, a location southeast of Cypress Island and to the west of Bellingham Channel, a channel which separates Cypress Island from Guemes Island. The pen was submerged from 65 ft (20 m) to 100 ft (30 m) underwater. ^[7] Pen #2 measured in at around 182 ft (55 m) wide by 436 ft (133 m) long.^[6]

The August 2017 pen break was preceded by an incident that took place a month earlier in the same pen between July 24-25 where the pen's mooring failed twice. This earlier incident occurred during the highest tidal current level in the summer of 2017.^[2]

The salmon pens were initially stocked with 369,312 smolts^[8] during May 2016 and had been scheduled to be harvested starting September 2017.^[9] At the time of the incident, the biomass held by the salmon pen was estimated to be at around 2,844,131 lb (1,290,076 kg).^[8]

Incident

The pen break was first reported by a citizen boater on August 19, 2017.^[10] The Washington State Department of Natural Resources estimated that around 243,000 to 263,000 Atlantic salmon escaped the pen, which was higher than Cooke Aquaculture Pacific's estimates.^[11] In one of its initial public reports, Cooke Aquaculture Pacific estimated that around 4,000 to 5,000 Atlantic salmon had escaped the farm.^[12] The company later estimated that around 160,000 fish had escaped the farm.^[11]

According to Cooke Aquaculture Pacific, the pen break was due to unusually strong tidal currents during that week's solar eclipse;^[12][5] but Washington State Department of Natural Resources investigators found that, while stronger than normal, the tidal currents were well within the range of which the net pens had survived in previous years, and the solar eclipse did not affect the tidal currents significantly.^[13] Instead, the investigators determined that insufficient maintenance and cleaning of the biofouling on the net pens was the primary cause of the break. Investigators found that pen #2 held around 110 short tons (220,000 lb; 99,790 kg) of biofouling, which was over 600% of the total original weight of the net pen.^[14]

Aftermath

In the immediate aftermath of the incident, the Washington State Department of Fish and Wildlife authorized the unlimited catching of escaped Atlantic salmon from the farm.^[12]

Around 57,000 of the escaped salmon were recaptured.^[11] Coastal tribes such as the Swinomish, Samish and Lummi were involved in recapturing the escaped farmed salmon.^[15] The Lummi declared a state of emergency and caught around 44,239 of the escaped Atlantic salmon, weighing in at around 392,913 lb (178,222 kg).^[8] The caught Atlantic salmon was sold back to Cooke Aquaculture Pacific, which paid out $30 per fish. Cooke Aquaculture offered to raise the purchasing price to $42 per fish if the Lummi were willing to, in return, abandon its pursuit of banning salmon aquaculture in its waters; this offer was refused by the Lummi Nation.^[15] In November and December 2017, Atlantic salmon was captured from the Skagit River by members of the Upper Skagit Indian Tribe.^[16] In April 2018, fishermen from the tribe continued to recover Atlantic salmon from the river, up to eight months after the incident.^[17]

In response to the accident, the Washington State Senate passed a law in March 2018 banning the farming of Atlantic salmon in the state by 2025.^[18] In April 2018, the Thurston County Superior Court upheld the termination of Cooke Aquaculture Pacific's farming license by the Washington State Department of Natural Resources, which effectively prevented the company from restocking its Atlantic salmon fishing pens.^[5]

References

External links

• Cypress Island Atlantic Salmon Pen Break, Washington State Department of Natural Resources