Leopard Seal Sightings and Population Counts at Macquarie Island

Macquarie Island hosts a long-term record of leopard seal sightings and annual population counts. The dataset, maintained by the Australian Antarctic Data Centre, includes individual seal records from 1948 to 2002 and yearly seal counts, documenting a periodic influx phenomenon. Data collection began in the mid-20th century through beach observations and tagging efforts.

Use Cases

• Analyze periodicity in seal arrivals by modeling the 'Year' and 'Number of seals' columns to identify 3-4 year cycles.
• Track individual seal movement and resighting history using the 'Seal ID', 'Tag #1', and 'Tag #2' fields.
• Correlate seal 'condition' records from sighting details with environmental data to study food shortage impacts.
• Study tagging methodology effectiveness over time by analyzing tag type metadata (e.g., 'Jumbo Rototag', plastic colors) associated with seal records.

Strengths

• Long-term temporal coverage with records spanning from 1948 to 2002.
• Contains detailed individual-level data including unique Seal IDs and tag histories.

Limitations

• Sparse data with few seals sighted since the 1980s, limiting statistical power.
• Incomplete time series with some years omitted due to unavailable data.
• Geographic scope is limited to a single location, Macquarie Island.

Provenance

Source

Australian Antarctic Data Centre (AU_AADC).

Collection Method

Data collected via direct observation and physical tagging of seals on beaches at Macquarie Island.

Time Range

1948 to 2002 for sightings; annual counts timeframe unspecified.

Freshness

null

Geography

Macquarie Island region, south of the Antarctic pack-ice zone.