Wintering Auk Abundance Surveys After the Erika Oil Spill

Two series of extensive aerial surveys recorded wintering auk distribution in the Bay of Biscay and English Channel, conducted at a 10-year interval after the Erika oil spill. The dataset supports spatio-temporal Bayesian models used to estimate population changes and the spill's impact. The 2011-2012 surveys counted 1.55 million auks in the study area.

Use Cases

• Fit spatio-temporal Bayesian models to survey data to predict auk abundance and analyze population trends.
• Estimate the impact of the Erika oil spill by comparing auk numbers within the affected area between the 2001-2002 and 2011-2012 survey periods.
• Identify major wintering areas by analyzing spatial distribution shifts, such as the strong southward movement into the Bay of Biscay.
• Assess conservation risks by modeling worst-case scenarios, like a major oil spill in the English Channel during peak February abundance.

Strengths

• Data spans two distinct survey periods at a 10-year interval (2001-2002 and 2011-2012), enabling longitudinal analysis.
• Surveys provide concrete population estimates, including a count of 1.55 million auks in the 2011-2012 winter.
• Study explicitly accounts for both spatial and temporal dependencies in species distribution modeling.

Limitations

• The dataset is limited to two winter survey periods, lacking continuous annual monitoring.
• Survey coverage is restricted to the French Atlantic coast, potentially missing broader population dynamics.
• Raw data structure, column details, and sample size are unspecified, complicating direct reuse.

Provenance

Source

Dryad digital repository.

Collection Method

Extensive aerial surveys repeated at intervals of 1–2 months.

Time Range

November 2001 to March 2002 and November 2011 to February 2012.

Freshness

Data was last updated in June 2020, with primary survey periods ending in 2012.

Geography

Bay of Biscay and English Channel off the French Atlantic coast.