The rodent capture synchrony contrast between Portal treatments was 0.049 in 1989–2014, with a time-block interval that included zero

We tested whether other rodents changed more synchronously across kangaroo-rat exclusion plots than across control plots at Portal, Arizona. We used data release 6.117.0 and 284 matched censuses from 1989 through 2014 on eight plots per treatment. All selected plots had 49 traps per census. We removed month effects and a linear time trend from square-root counts of named target rodents other than Dipodomys. Mean pair correlation was 0.698 on exclusion plots and 0.650 on controls. The contrast was 0.049, with a nominal 95 percent interval of -0.004 to 0.098 from joint blocks of 12 observed censuses. This interval assumes roughly stable adjusted series and conditions on the selected plots. The planned test did not establish a positive aggregate difference or equal synchrony. Exploratory species contrasts were +0.166 for Chaetodipus baileyi and -0.145 for C. penicillatus. Removing C. baileyi changed the aggregate contrast to -0.050. Independent random thinning of exclusion captures to the control mean gave a mean contrast of -0.035 across 2,000 draws. Thinning is an observation sensitivity check; it does not correct detection error or prove its cause. Adjacent-census changes gave a contrast near zero. The package includes unmodified CC0 source tables, provenance, code, figures, results, an internal analysis plan, and repeat instructions. An independent rebuild matched all 4,544 plot-census counts. This one-site capture analysis does not identify true population synchrony, a climate effect, or extinction risk.

spatial synchrony · Portal Project · rodents · species interactions · observation error · reproducibility