Parks Canada closes the Gros Morne Mountain summit trail every year from around May 1 to late June to protect arctic hare, rock ptarmigan and caribou during their most vulnerable weeks of reproduction, and to protect fragile alpine soil during spring thaw. The approach trail to the base stays open.
Citation
Parks Canada annual area-closure bulletins and the Gros Morne Mountain trail page, Gros Morne National Park.
Study overview
The summit plateau of Gros Morne Mountain is a pocket of Arctic-alpine tundra far south of where that environment usually occurs. Several species raise their young there in spring, and Parks Canada closes the summit trail annually to give them an undisturbed window to do so.
Methodology summary
The closure window is based on known breeding and calving timing for the species involved, combined with observed soil conditions during spring thaw, rather than a single fixed calendar rule.
Key findings
- Rock ptarmigan chicks are highly vulnerable in their first week after hatching and need their mother's warmth every few minutes; a few minutes of disturbance in cold, wet weather can be fatal to chicks.
- Caribou calves are born on the mountain during this window and need an undisturbed period to gain the strength and mobility to keep up with their mothers.
- Alpine soils that are still wet or frost-heaved in spring are unusually easy to erode under foot traffic, adding a terrain-protection reason alongside the wildlife one.
- The 4.5-kilometre approach trail to the base of the mountain remains open throughout the closure; only the summit trail is affected.
Limitations
The exact reopening date is not identical every year — it has fallen anywhere from June 27 to June 29 in recent years depending on conditions, rather than a fixed date. This is a precautionary park-management policy informed by wildlife biology, not a single peer-reviewed study with its own published dataset.
Practical meaning
If your visit falls between May 1 and late June, plan on the approach trail rather than the summit, and confirm the exact reopening date for your travel dates with the Gros Morne Visitor Centre rather than assuming a fixed date from a previous year.
Last updated: August 2, 2026 · Editorial team