New population data can only be added to the Living Vermont Index database if they meet certain requirements. The study has monitoring data for at least one species at a particular place as a time-series with at least two years of data. The LVI uses these time-series to track trends in the abundance of populations from across the state as an overall index.
Specific types of population abundance data used by the LVI
- Full population count
- Estimate (e.g. where population size was estimated from measured parameters)
- Proxy (e.g. breeding pairs, nests, tracks)
- Measure per unit effort (e.g. the number of fish caught per net per hour)
- Biomass (e.g. spawning stock biomass)
- Sample (e.g. where a proportion of the population is regularly monitored)
Data types that are not used in this database
- Data from experimental observations (testing different treatments to populations over time)
- Survival rate (although the data used to calculate it may be use. e.g., mark-recapture)
- Recruitment data such as number of eggs or young
- Catch or hunting data unless there has been a measure of effort
- Data where changes in survey area or method has changed over time and this has not been corrected
General data requirements and information collected by the LVI
Abundance data need to have been collected from a single species of plant or animal over a period of at least two years (which do not need to be consecutive). Information is also needed on the geographic location and method used. To present an accurate measure of abundance change, it is important that both of these are the same in each year. If the method changes within the study period, the data should be entered separately. If only part of the dataset is appropriate for entry, all other values should be excluded. The data may come from a variety of sources, as long as these are referenced and traceable, including peer-reviewed scientific articles, books, government reports, online databases, and other literature.
Contribute to the LVI
You can contribute to the Living Vermont Index by adding a monitoring project using our online form or by downloading our template data entry form (coming soon).