Harbor Seal Distribution and Abundance in the St. Lawrence Estuary and Gulf

1994-2001 aerial survey data provides a snapshot of harbor seal distribution and mean abundance during summer pupping and moulting seasons. The dataset maps areas of high, medium, and low seal abundance based on thresholds of 10, 30, and 50 individuals. It integrates unpublished monitoring data from Parks Canada and SÉPAQ for the Saguenay Fjord and Pointe-aux-Vaches tidal flat sectors.

Use Cases

• Map harbor seal abundance classes (high, medium, low) across the Estuary and Gulf of St. Lawrence using the defined individual count thresholds.
• Analyze seasonal distribution shifts by comparing seal presence between June (pupping) and August (moulting) survey periods.
• Identify important haulout sites in the Saguenay Fjord and Pointe-aux-Vaches tidal flat sectors categorized as high abundance areas.
• Validate published haulout site utilization results from Robillard et al. (2005) using the provided abundance class mapping.

Strengths

• Data is derived from multiple aerial survey campaigns conducted over a 7-year period from 1994 to 2001.
• Abundance classification uses specific, published thresholds (e.g., >30 individuals for high abundance in the Estuary).
• Integrates unpublished monitoring data from authoritative sources like Parks Canada and SÉPAQ for key sectors.

Limitations

• Data represents a snapshot from 2005 and may not reflect current seal population distributions.
• Coverage is limited to summer months; spring and fall distributions are explicitly noted as unknown.
• Abundance classes are described as arbitrary, though they align with published results.

Provenance

Source

Fisheries and Oceans Canada, integrating data from Robillard et al. (2005), Parks Canada, and SÉPAQ.

Collection Method

Primarily aerial surveys conducted at low tides during June and August, supplemented by unpublished monitoring data.

Time Range

1994-1997, 2000, 2001 (survey years); map represents the 2005 situation.

Freshness

The most recent mapping available is from 2005, though the record was last updated in March 2026.

Geography

Estuary and Gulf of St. Lawrence, including the Saguenay River, Saguenay Fjord, and Pointe-aux-Vaches tidal flat.