Table 1 Indices calculated from the respondents’ answers about the use of the organs and excrements of vultures
Index | Calculation | Explanation and reference |
|---|---|---|
Use value (UV) | UV = \(\frac{{\sum {\text{SI}}}}{N}\) SI: a respondent who reported a specific use category for a given species N: the number of respondents | Identifies the species-specific relative importance of each use category mentioned by the respondents [37, 38] |
Informant consensus factor (FIC) | FIC = \(\frac{{N_{{{\text{ur}}}} - N_{{\text{t}}} }}{{N_{{{\text{ur}}}} - 1}}\) Nur: number of use-reports for each usage category Nt: number of usage categories mentioned by the responds | Identifies the level of consensus among the respondents about species-specific use categories; ranges between 0 and 1 and increased values indicate higher consensus [39] |
Use diversity index (UD) | UD = \(\frac{{U_{{{\text{cx}}}} }}{{U_{{{\text{ct}}}} }}\) Ucx: number of records of a species within a use category Uct: sum of records of a species across all use categories | UD measures the importance of a species-specific use category and how evenly a species-specific use category contributes to its total use for a species [40]; ranges between 0 and the number of use categories for a species |
Use equitability value (UE) | UE = \(\frac{{{\text{UD}}}}{{{\text{UD}} _{{{\text{max}}}} }}\) UD: diversity of use for a given use category of a species UDmax: maximum possible UD for a species with uses in a given number of categories | UE measures how evenly the different uses contribute to the total use of a species independent of the number of use categories [41]; ranges between 0 and 1; following Awo [42] we assume that knowledge of use is equal if UE ≥ 0.5, and unequal if UE < 0.5 |
Citation frequency (CF) | CF [%] = \(\frac{n}{N}\) × 100 n: number of citations for a specific organ of a species N: total number of respondents mentioning a species to be used | CF measures the species-specific diversity of uses of certain organs and excrements of vultures [43] |
Fidelity level (FL) | FL [%] = \({ }\frac{{N_{{\text{p}}} }}{N}\) × 100 Np: number of informants who mentioned a specific organ of a certain species to be used N: sum of citations of all organs to be used in different use categories | FL is the percentage of informants claiming the use of a certain organ [44] |