Parks Canada staff show how spruce budworm look crawling on a tree/Parks Canada

Parks Canada has decided that Gros Morne National Park won’t join an early intervention spraying program to control spruce budworm.

“Spruce budworm is a native forest insect, and episodic outbreaks are a natural ecosystem process that leads to forest diversification and renewal but can also affect the forestry industry and domestic wood harvesters,” the park said in a written statement.

The Government of Newfoundland and Labrador had asked Gros Morne to join an Early Intervention Strategy (EIS) control program in the western part of the province. It wanted to spray about 22 per cent of Gros Morne — 400 of its 1,805 square kilometres (154 of 700 square miles).

Parks Canada reviewed policies and “best available evidence,” and considered feedback from a public consultation process. It determined that intervening “could impact the ecological integrity of its forest ecosystem” and said the “scientific review also found there is limited evidence to suggest that including Gros Morne in the program would be necessary for the success of the EIS outside the park.”

The (eastern) spruce budworm (Choristoneura fumiferana) is a moth native to North America that mainly feeds on balsam fir and white spruce and occasionally on red and black spruce. It devours needles and sometimes staminate (male) flowers and cones, killing trees within five years. Spruce budworms usually exist in reasonable numbers, but outbreak cycles happen every 30 or 40 years. They were first spotted on the island of Newfoundland in 1942 and the last outbreak in the 1970s caused a tree loss equal to a 25-year supply of wood to the forest industry. The current Canadian outbreak started on the north shore of the St. Lawrence River in Quebec in 2006 and has harmed more than 9.6 million hectares (almost 24-million acres) of forest while spreading east. 

An aerial view of Gros Morne National Park's forests and waterfalls/Parks Canada

Parks Canada will still work with partners by supporting EIS research and monitoring, which can contribute to scientific understanding of the efficacy of the strategy and its effects on the health of the forest ecosystem.

The EIS is a research program being delivered by the Healthy Forest Partnership which includes Natural Resources Canada’s Canadian Forest Service, all four Atlantic provinces, academia, and the forest sector. EIS is a novel management approach that involves treating spruce budworm “hotspots” (smaller areas where populations are still low, but are increasing) to hopefully prevent outbreaks, with minimal or no defoliation to forests. The stragegy uses aerial spraying of the pesticide Btk to keep budworm populations below levels where they can be controlled by natural mortality.

The program was initiated in western Newfoundland in 2020 in areas outside of the national park and will continue in 2021.

Established in 1973, Gros Morne is renowned for its unique and varied geography and dramatic topography shaped by periods of glaciation over the last two million years. It boasts diverse coastlines, serpentine barrens in an area called the Tablelands, an arctic-alpine environment, extensive wetlands and boreal forest. It protects two natural regions — the Western Newfoundland Highlands and the eastern portion of the St. Lawrence Lowlands.

UNESCO gave Gros Morne World Heritage Site status in 1987 because of its “exceptional natural beauty “and “outstanding examples of major stages in the earth’s geological evolution."