Demography of marine birds in the Northeast Atlantic: informed parameter values for population modelling
Data files
Oct 23, 2025 version files 25.99 KB
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Model_output_overview_Dryad.xlsx
23.40 KB
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README.md
2.58 KB
Abstract
Matrix models are often used to assess and predict the impact of human activities on wild populations. These models require input values of demographic parameters, i.e. survival and fecundity. However, empirical estimates of these parameters are often not available, particularly for survival.
We built matrix population models for 25 species of marine birds in the Northeast Atlantic. These models were based on long-term monitoring data on abundance and breeding productivity, collated for an environmental status assessment under the OSPAR Convention for the Protection of the North-East Atlantic. We started with literature-based values of age-specific survival and tuned these values to fit the observed population growth rate.
This database presents tuned values of age-specific survival for 25 species in four regions of the north-east Atlantic, a total of 54 regional populations. In addition, we report modelled generation time as well as the level of breeding productivity required to maintain a stable population for the same populations.
Practical implication. Our tuned values of age-specific survival should be used as starting values in future modelling exercises. They represent means over relatively large scales and long timespans and may need adjusting to local conditions.
Dataset DOI: 10.5061/dryad.4mw6m90qn
Description of the data and file structure
This dataset includes model-derived estimates of demographic parameters for 58 populations of 25 marine bird species in Northwest Europe
Files and variables
File: Model_output_overview_Dryad.xlsx
Description: Model assumptions, empirical estimates and model output
Sheet: Data
Variables
- Species
- Common name
- Scientific name
- Clutch size (1 or +1)
- Region (OSPAR Region, see https://www.ospar.org/convention/the-north-east-atlantic)
- Assumptions
- Age of first breeding (years)
- Breeding propensity (proportion)
- Base parameter values (from literature). "n/a" for survival indicates that survival of the age class in question was considered equal to adult survival.
- Breeding productivity (fledged chicks/pair/year)
- S0_base: first-year annual survival probability
- S1_base: second-year annual survival probability
- S2_base: third-year annual survival probability
- S3_base: fourth-year annual survival probability
- S4_base: fifth-year annual survival probability
- S5_base: sixth-year annual survival probability
- SA_base: adult annual survival probability
- Source: reference code, see sheet 'References'
- Empirical estimates (from monitoring data)
- Mean productivity (fledged chicks/pair/year)
- n colonies (number of colonies monitored for productivity)
- Lambda (annual finite population growth rate, assuming exponential growth)
- Tuned parameter values (output from model)."n/a" for survival indicates that survival of the age class in question was considered equal to adult survival.
- S0: first-year annual survival probability
- S1: second-year annual survival probability
- S2: third-year annual survival probability
- S3: fourth-year annual survival probability
- S4: fifth-year annual survival probability
- S5: sixth-year annual survival probability
- SA: adult annual survival probability
- Model output
- B-lambda_1: mean breeding productivity required to stabilize population (fledged chicks/pair/year)
- Generation time: estimated generation time of stable population (years)
- Comments. "n/a" indicates no specific comment.
Sheet: References
Variables
- Number: reference code, see variable 'Source' in sheet 'Data'
- Reference: citation for published source