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DDT – Miramichi Fish Hatchery

Early settlers could be selective from the abundant forest, fish and minerals. As the population grew and the demand for raw materials increased, it soon became evident that some resources would be seriously reduced or wiped out if improperly managed. Man-made changes were the basic reason.

As would be expected, particularly in New Brunswick, Nova Scotia and perhaps Newfoundland the forest industry must be held responsible for the major environmental changes affecting fish. They have been either directly of indirectly responsible for reducing the productivity of some of the finest salmon, alewives, smelt and other anadromous fish.

Contributing to the threat has been the destruction of spawning grounds and the eggs and fry therein through the physical action of log drives. This method was the chief means of transportation of timber to the mills and pulp plants in the early days on the Miramichi River.

Also associated with the forest industry but hardly its fault, is the necessity for control of forest pests. The outstanding example is the DDT (dichloro-diphenyl-trichloroethane) spraying program for spruce budworm. From 1952 to 1957, 11 1/2 million acres were covered at a cost of over ten million dollars. This is well over half the forested area of New Brunswick. The chemical had disastrous effects on the young fish and stream insects.

The forest of New Brunswick and the Gaspe peninsula were suffering from a severe outbreak of the spruce budworm. This insect pest feeds mostly on the needles of balsam fir and spruce, and can kill trees of all ages. In 1952 the lumber industry started to control the insect and save the trees in northern New Brunswick by spraying the woods with DDT insecticide from aircraft. The next year a new company, Forest Protection Limited, was formed by several lumber companies and the Province of New Brunswick, to handle budworm control. This company, in cooperation with the Federal Government, had continued extensive spraying operations over new areas each year until the early '60's. In 1953 and 1954 the insecticide was applied at the rate of 1/2 lb. Of DDT per acre, (one poung per acre in 1952).

In the face of such widespread and repeated applications of DDT many biologists, sportsmen and naturalists were increasingly worried about the side effects of the insecticide on fish and wildlife in the budworm-infested areas. Fisheries workers were especially concerned because many species of fish were known to be extremely sensitive to DDT.

In June, 1954, the million acres in New Brunswick which were sprayed with insecticide included about one third of the watershed of the Miramichi. This gave the first opportunity for anyone to study the effects of DDT on stocks of Atlantic salmon which had been under close observation before spraying.

For the first time a complete watershed supplying water to a fish rearing station was in the spray plan. With the knowledge of all concerned this was sprayed at the indicated time including the storage pond and the station itself. The Company, with prior permission, operated a filter system on one line of the water supply. What happened? In line with the assumption that had been washed out the year before, most of the fish survived the bombardment and grew large.
Early in the spray operation, the watershed supplying water to the Miramichi Fish Hatchery was sprayed. The results were disastrous. About 25% (925,000) of the hatchery stock of salmon fry died over a period of two weeks from DDT poisoning and the Company was sued for damages by the Queen in the right of Canada.

In cooperation with the Fisheries Research Board of Canada, tests of parr mortality due to DDT spraying used to combat the spruce budworm in New Brunswick, were carried out on several branches of the Miramichi River. The method involved the impoundment of yearling parr in fine wire containers. Mortalities appeared high. A heavy parr mortality in the Sevogle and North West Miramichi Rivers was reported following a big rise in the level of the river.

A verbatim account of the DDT spraying at the Miramichi Fish Hatchery:

Mr. CharlesJ.A. Hughes,
551 King Street,
Fredericton, N.B.
July 10, 1956

Dear Mr. Hughes,
Mr. James Catt, Regional Supervisor has directed me to write you an account of the budworm spraying at Miramichi hatchery. On June 9th, the planes were flying over the hatchery and ponds from early morning until noon about 10A.M.. I noticed the first spraying three planes come over the top of the trees not more than two hundred yards from the buildings. Two dark colored planes and one sort of yellow color near as I could tell they were all spraying then around 11:30 A.M. three more planes come over the yellow colored plane passed by the side of the buildings and over the ponds I could see a heavy spray coming from that plane the other planes were a little further away and all the spraying, If I had thought I could have easily got their numbers.

I saw the oil slick on the water in the ponds and troughs soon as I come out after dinner about 12:45 we could barely stay in the hatchery for the smell of the DDT and the salmon were piling down to the lower ends of the troughs and getting weak. The trout were effected immediately a lot of them come to the top of the water they started to die around seven the evening of the 9th, the same day they were sprayed and were nearly all dead Sunday morning. A lot of the salmon fingerlings died the night of the 9th, and all through the next week. The most loss in the yearlings was June 14th and 15th. It started to rain the evening of the 9th and rained some through the night and Sunday the 10th.
Dr. Ide and two students also a man by the name of Jones that works with Dr. Kerswill were here when they were spraying also the hatchery staff, T.I. Mullin Assistant, Jermiah Oshea, Leo McKibbon. It is hard to tell which way the rain come in this valley a storm whirls around in all directions. Dr. MacKenzie who works with smelts saw all the dead fish in the ponds and hatchery on Sunday and the oil slick on the water.

Yours very truly,

M.N. Jordan


  • Fish Culture Development - A Report of the Fish Culture Development Branch of the Conservation and Development Service - 1954 Reprinted from the Twenty-Fifth Annual Report of the Department of Fisheries of Canada. Pg. 6.
  • Forest Spraying of Insecticide in New Brunswick to Control Damage from an Outbreak of Spruce Budworm. by B.W. Flieger Manager, Forest Protection Ltd.
  • Preliminary Observations on Effects of 1954 DDT Spraying on Miramichi Salmon Stocks. Fisheries Research Board of Canada, issue No. 62, pp. 17-24, July, 1955.
  • The Canadian Fish Culturist, issue Twenty Four, Febuary, 1959 Effects of Spruce Budworm Control on Salmon and Other Fishes in New Brunswick by Miles H.A. Keenleyside
  • The Canadian Fish Culturist, Issue Twenty-Five, October, 1959 The Effects on Fisheries of Man-Made Changes in Fresh Water in the Maritime Provinces by A.L. Pritchard