Four duration slope intervals included proportional catch scaling in Sweden and Madagascar in 2019-2020

We tested whether insect mass scaled with collection duration after trap, season and weather controls. We used 5,805 measured catches in two periods per country. Duration slopes were 0.96 and 0.92 in Sweden and 0.62 and 0.48 in Madagascar. All four family-adjusted intervals included the proportional-scaling value one. Both Madagascar 95 percent intervals were below one before correction. Early Madagascar results changed with duration filters and model choices. Most Madagascar durations were near seven days. These results neither establish proportional scaling nor show trap saturation. One sampling year per country, few time clusters and nonrandom schedules limit inference. We test no pollution effect or long-term climate trend. The package gives code, aggregate results, source hashes and retrieval instructions.

insect biomass · observation bias · collection duration · weather · seasonality · null result