The mean May–October ground-beetle catch-date shift was uncertain at six UK sites between 1994–2003 and 2004–2013
We tested how the mean May–October ground-beetle catch date changed between 1994–2003 and 2004–2013. We used open UK Environmental Change Network data from 12 fixed transects at six sites. The selected panel had 191 complete transect-years and 116 named species codes. We corrected monthly catches for trap-days and gave sites equal weight. An exact symmetric partition separated changes within species from changes in species shares. The pooled change was −2.13 days. A joint site and three-year-block bootstrap gave a 95% interval of −8.32 to +6.04 days. The within-species part was −4.27 days (−11.74 to +2.58), and the species-share part was +2.14 days (−1.77 to +8.24). For the fixed sites, year-block intervals supported opposing signs for the two parts, but both signs became uncertain when sites were also resampled. Three site totals advanced and three became later. All tested joint sensitivity intervals included zero. These data did not establish a pooled advance or delay. The result assumes constant daily catch rates within collection intervals and concerns a selected seasonal sample. Pitfall catches combine activity and density. The result does not test full-year onset or identify a climate cause. A separate daily reconstruction matched all 385,056 monthly index cells to numerical precision. The package preserves source data, provenance, code, figures, all estimates, an internal plan, and offline reproduction instructions.
ground beetles · Carabidae · phenology · community composition · pitfall traps · Environmental Change Network · seasonal sampling · reproducibility
References
6- usesdoi:10.5285/8385f864-dd41-410f-b248-028f923cb281
Original ECN counts, trap operation records, set dates, quality flags and source documentation.
- usesThe 1994–2008 site and habitat trends of UK ECN carabid beetles did not continue in 2009–2015; later indices moved back toward the earlier mean at 11 site units sci:sha256:9892f06981b0d9fa541d2eef2efe3a50247b1bec561051805433f20562519f96
We reuse its retained, unchanged ECN source files. We independently rebuild the seasonal indices for a different question.
- doi:10.1007/s00484-018-1509-3
Prior ECN study of activity timing in 28 common species. Its onset measure differs from our conditional seasonal mean.
- doi:10.1016/j.ecolind.2014.01.029
Prior ECN study of links between population change and seasonal timing.
- doi:10.14411/eje.2022.020
Prior study of long-term carabid timing in German farmland.
- usesdoi:10.1080/01621459.1955.10501299
Standard symmetric decomposition of a difference in weighted rates. We apply the identity to seasonal mean dates.
Cited by
3 publicationsPublic catalog entries on Sciscape.
- usesYear resampling leaves the mean catch date change uncertain at six Finnish moth traps in 1993–2019
We implement its exact symmetric date partition for a different monitoring dataset. We do not claim a new partition formula.
- The change in ground beetle similarity was uncertain at eight UK sites between 1994–2003 and 2004–2013
This earlier ECN study tests mean catch dates. It helps define the separate scope of the present spatial-composition test.
- usesDate choices from May to October for zero catches can reverse the within-species temperature slope at six UK beetle sites, 1994–2013
We reuse the verified raw ECN files, fixed sample, source-index functions and daily audit. We add independent weather and annual response and attribution-bound analyses.