Beluga Calf Summer Density in the St. Lawrence Estuary 1990-2009

1990 to 2009 data from 35 aerial surveys depicts the relative summer density of beluga calves in the St. Lawrence Estuary. The dataset was created by Fisheries and Oceans Canada using kernel density estimation to define and characterize beluga habitat as part of an Ecosystem Research Initiative.

Use Cases

• Map relative summer density of beluga calves using kernel density estimation outputs for habitat characterization.
• Analyze spatial distribution patterns of beluga calves across the St. Lawrence Estuary from 35 survey flights.
• Integrate density distribution layers with other ecosystem variables for beluga habitat modeling.
• Assess changes in calf density areas over the 1990-2009 survey period for population trend studies.

Strengths

• Data is derived from 35 systematic aerial surveys conducted over a 20-year period (1990-2009).
• Density boundaries are defined using a statistical method (kernel density estimation) for a smooth, continuous distribution.
• Produced by a government science division (Fisheries and Oceans Canada) with supporting peer-reviewed advisory reports.

Limitations

• The dataset provides relative density, not absolute population counts, limiting direct abundance estimates.
• Data is temporally stale, with the last survey conducted in 2009 and no updates reflected in the core analysis.
• Specific sample sizes (rows) and attribute columns (features) for the underlying survey data are not documented.

Provenance

Source

Fisheries and Oceans Canada (DFO) Science Division.

Collection Method

Kernel density estimation applied to observations from 35 aerial surveys.

Time Range

1990 to 2009.

Freshness

Metadata indicates a last update in 2026, but the underlying survey data covers 1990-2009 only.

Geography

St. Lawrence Estuary, Canada.