SpruceRoots Magazine - February 2002

SpruceRoots Magazine - July 2003

SALMON SCIENCE

by Erica Thompson

In the world there is an ancient balance set delicately between abundance and scarcity. In the Pacific Northwest the distribution of salmon species, their life cycles and the geography of their home waters are one of these mystical symmetries. In all but a handful of rivers, Pink salmon return every second year to spawn. Along BC’s southern coast, Pink salmon spawn in years ending in odd numbers, such as 1999 and 2001. Along the north coast, they push up rivers on even numbered years, such as 2000 and 2002. However, there are a handful of rivers which are curious exceptions to these natural patterns negotiated between salmon and river and the Tlell is one of these. Every autumn Pink salmon return to the Tlell River — odd or even.

There is am interesting story set within the Tlell’s anomaly. It is about Pink salmon and a fisheries biologist who tried to change the natural patterns of a small creek called McClinton. The Tlell’s perennial pink caught the attention of A.L. Pritchard while he was working for the Nanaimo Pacific Biological Station in the 1920’s. Biologists thought that if they could create an odd-year pink run in Masset Inlet, like the Tlell’s, it would be a perfect marriage of science and industry for the sake of prosperity. The promising combination of immense productivity, the opportunity to investigate and research escapement and abundance theories, and the potential commercial returns to the packing industry fueled Pritchard’s interest in duplicating the Tlell’s annual pink returns in McClinton Creek, Masset Inlet.

In the early 1900’s, pink salmon had assumed an important role within the commercial fisheries due to the growing demand for canned salmon and according to Pritchard’s notes, from the already apparent decrease in some areas of the more ‘valued’ species such as sockeye. McClinton Creek had a vibrant even-year pink run as did the Mamin, the Datlamen and the mighty Yakoun River, known as ‘the river of life’. By the 1930’s, there were three companies operating four canneries along the Inlet and while the corporations were reeling in the dollars during the ‘on’ years of the Pink runs, the ‘off’ years were proving to be a ‘bust’ to their coffers.

Pritchard’s description of the amount of salmon harvested in these times is startling. In a report to Ottawa, he tells how “in 1930, in this inlet, over two hundred thousand cases were canned. This number represents the capture of at least four million fish. Furthermore, since the streams were well seeded in all cases, it is safe to assume that at least as many more escaped, implying a minimum total run of eight millions [sic].”

“It is easy to realize,” wrote Pritchard, “just what this absolute failure of fish means from the economic point of view…these concerns are at present reaping benefit from their large investments only once in every two years.”

Building an artificial salmon run, even at the turn of the century, was not popular science. There were few precedents, and even fewer successful ones for Pritchard to follow. Attempts to build a pink run at Puget Sound from Alaskan eggs had failed in the early 1920’s though small degrees of success had been attained in the transfer of eggs from Alaska to Maine, Maryland, New Jersey and New York along the eastern seaboard. Pritchard’s determination to change the natural balance established over thousands of years in the Island’s rivers and creeks set him on a path along which he would labour from 1930 to 1942. With an economic mandate clearly behind him, Pritchard began working to emulate the perennial productivity of the Tlell at McClinton Creek.

In 1930, Pritchard’s team installed their first fish fence on the Tlell River. Female pinks were stripped of their eggs and the milt from the males collected after they were trapped. The eggs were immediately fertilized and then water hardened. Packed into carrying trays, the eggs were boxed and transported to an ‘eyeing station’ at McClinton Creek where they remained until they were put into the creek as free swimming fry.

In total, 1,131,700 eggs were taken that year from the Tlell, and from hatchery racks 877,650 free-swimming fry were released during the spring and winter of 1932. Of the near one million fry released, 124,002 were marked by the removal of the adipose and left ventral fins to help identify the two-year-olds upon their anticipated return to Masset Inlet.

Two years later, in the fall of 1933, eager fisheries officers awaited the return. Counting efforts were stepped up both on the Tlell River and McClinton Creek, but hopes proved higher than any counts. Of the 19,000 pinks waiting to spawn in the Tlell River, not a single adult fish marked during Pritchard’s program was identified and not one single pink was recorded at McClinton Creek. The only marked fish found along the coast were forty pinks which made their way up the Fraser River.


In the autumn of 1933 another 695,200 eggs were taken from the Tlell, and with a restricted budget of the Depression era, 540,294 eyed eggs were planted directly into the spawning gravel at McClinton to save money spent on caring for them over the winter. However, that year there were two unusually heavy rains which Pritchard believed washed the fry prematurely from the creek. Later in the year only five fry reached the fence on their way down stream.

In 1935, Pritchard made his final attempt using Tlell River stock to establish an odd-year pink run in Masset Inlet. In the spring, 505,857 unmarked free-swimming fry and 108,200 marked by the removal of the adipose and right ventral fins were placed into the system. Two years later fisheries officers prepared for the return hopeful their hypothesis would be successful this time. Those officers stationed at the Tlell fence recorded 2,052 females and 2,194 males but there was not one fish exhibiting the clipped adipose and right ventral fins from the 1935 cycle.

The situation was worse for Pritchard at McClinton Creek.

“All the streams in Masset Inlet were thoroughly examined by officers of the Biological Board of Canada and the Department of Fisheries but no sign of a Pink salmon was seen with the exception of one which found its way into the east tributary of McClinton Bay. No “marked” fish were reported from the fishing areas,” wrote Pritchard. Although he did cite the success of the six fish returning to McClinton, he admitted this could not be considered in any way an “economic success.”

“On the basis of the three completed experiments the conclusion is inevitable that the transfer of Pink salmon eggs from the Tlell River to McClinton Creek in an effort to build an “off-year run has been unsuccessful.” His journey between McClinton and the Tlell was over. •
From
Water Flowing to the Sea: the Tlell Watershed Legacy Project..

Illustration:
The mouth of the Tlell River,
Haida Gwaii : SRs/InHouse