Table 1.
Description of the variables used within the structural equation models.
| Variable | Description |
|---|---|
| Attendance | Annual institution attendance (2015) |
| Species richness | Total number of species per institution (2017) |
| Total animals | Total number of individual animals per institution (2017) |
| Mammal species richness | Total number of mammalian species per institution (2017) |
| Institution area | Institutional area in hectares (ha; 2015) |
| Threatened species proportiona | The proportion of the International Union for the Conservation of Nature (IUCN) Red List of Threatened SpeciesTM ‘threatened’ species (‘Critically Endangered’, ‘Endangered’ and ‘Vulnerable’) per institution (2017) |
| Mean species body massa | The mean species body mass per institution (g; 2017) |
| Diversity | Brillouin index measure of within collection diversity (alpha diversity; 2017) |
| Dissimilarity | The mean Raup–Crick dssimilarity index per institution, measuring compositional dissimilarity between collections (2017) |
| GDP | Gross domestic product (US$; 2015) |
| National population size | National population size for each country (2015) |
| 10 km Population | Estimated population count within a 10 km radius of the institution (2015) |
| In situ contributions | The annual number of field conservation programmes in which individual AZA member institutions contribute to in some capacity (2015) |
aWeighted for species abundance per institution