The foundation for all nature monitoring is the collection of time series data for different variables, and this applies also to our work following the status of our seabird populations. A time series is constructed by regularly measuring a variable over time.
In SEAPOP, monitoring encompasses annual measurements of how populations of different seabird species are doing at any given time, reflected firstly through variables such as population size (how many are breeding), breeding success (how many young are produced) and the survival of breeding birds from year to year. For some species we also register what and how much the birds eat (diet) and the time at which they breed (phenology).
The largest part of this monitoring occurs at selected key sites. This is further described below, with a more detailed explanation of, and access to, the five central time series variables.
Changes are explained by coupling time-series data
The different time series can be coupled with parallel time series for the environmental conditions that the birds have experienced, e.g., variations in the stocks of their most important prey species, or climate changes and disturbances in the birds’ habitats. Statistical models of such relationships help explain the demographic changes we observe in the populations. These results also make it possible to create more precise prognoses for the further development and viability of the populations, because expected changes in the birds’ most important living conditions, e.g. as a result of changes in climate, can more realistically be taken into account.