Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1002/eap.2196
Licence creative commons licence
Title (Primary) Analysis of monitoring data where butterflies fly year‐round
Author Comay, O.; Yehuda, O.B.; Benyamini, D.; Schwartz‐Tzachor, R.; Pe'er, I.; Melochna, T.; Pe'er, G.
Journal Ecological Applications
Year 2020
Department iDiv; ESS
Volume 30
Issue 8
Page From e02196
Language englisch
Keywords Butterflies; phenology; warm climate; modelling; Citizen Science; abundance
Abstract Butterfly Monitoring Schemes (BMSs) engage the public in conservation and provide data sets that cover broad geographical areas over long timescales. Most existing BMSs are in temperate climates; however, the Israeli Butterfly Monitoring Scheme (BMS‐IL), established in 2009, is a notable exception as it encompasses a large climatic gradient from Euro‐Siberian through Mediterranean to hyper‐arid regions. Israel’s climate poses challenges in analyzing data from year‐round butterfly activity, as in other tropical or arid countries. The Regional Generalized Additive Model (Regional GAM) is a butterfly phenology and abundance model based on repeat visits throughout species’ flight season. We tested the applicability of Regional GAM for species with complex flight seasonality (e.g., multivoltine) by comparing estimated abundance and seasonal indices for the full data set and rarefied subsets. We assessed the reliability of modelled flight seasons and compared abundance estimates per site resulting from biologically plausible and unreliable seasonal models. The reliability of Regional GAM rises with the number of observations, and the model tends to produce more biologically plausible models for species with simple phenologies (e.g., univoltine with a single peak in activity). Abundance estimates based on unreliable models produce values with inter‐quartile ranges of 90%–153% compared with biologically plausible models, while peak time changes with an inter‐quartile range of 0 to 22.5 days when comparing all rarefied models with the full data set. Regional GAM should be applied with great caution for rare species and those with a complex flight season, and the date of year‐start needs to be carefully chosen for species that are active year‐round. We identified the key sources of error and propose an operational workflow to address them. With few adaptations, Regional GAM can support new BMSs in analyzing data where butterflies are active year‐round, including tropical climates. We propose guidelines for analyzing BMS data for species or regions with long activity periods and complex phenologies.
Persistent UFZ Identifier
Comay, O., Yehuda, O.B., Benyamini, D., Schwartz‐Tzachor, R., Pe'er, I., Melochna, T., Pe'er, G. (2020):
Analysis of monitoring data where butterflies fly year‐round
Ecol. Appl. 30 (8), e02196