EMF Evidence Library
Research library/Wildlife & environment/ECO-007
ECO-007Original text reviewed

Magnetic-compass disruption extends to 75-85 MHz in blackcaps

Leberecht et al. · 2022 · Journal of Comparative Physiology A

The reported finding

Controls oriented and shifted with the rotated geomagnetic field. Under RF noise, headings were indistinguishable from random and significantly more dispersed than controls.

Reading it carefully

Laboratory orientation is a functional endpoint, not observed migration mortality, population decline or human health risk. Radical-pair compatibility does not identify the in-vivo sensor conclusively. Same Oldenburg/Oxford research network as 2014/2016.

Inside the study

Exposure conditions
75-85 MHz broadband noise, 2.53 pT/√Hz reported max-hold spectral density. Three aluminium-shielded chambers; normal and 120°-rotated static magnetic fields. Magnetic/electric spectra measured daily. Spectral density is not total magnetic field.
Design & controls
Eurasian blackcaps in two seasonal cohorts, spring 2019 and 2021; same individuals tested across four conditions, n=27-32/condition after activity exclusions. Blinded orientation assessment; control pre-screening and subsequent fresh test series.
Statistics
Normal control: n=32, r=.4018, P=.005; RF: n=27, r=.1237, P=.6655. Rotated control: n=31, r=.4122, P=.0044; RF: n=29, r=.0740, P=.8552. Bootstrap directedness comparisons P=.00854 and .00902.
Related research & shared cohorts
Online 2021, issue 2022: one paper. No independent laboratory replication of this 75-85 MHz protocol established in this pass.
The protection question raised
Do environmental spectra overlap conditions that disrupt this bird compass, and are there population consequences? The later frequency-band result extends a related programme rather than providing independent multispecies confirmation.
Source verification
Original full methods, results and disclosures reviewed in PMC XML; Scite forward graph traced the programme.
Where to find the result
Generation and Measurement of Time-dependent Fields; Behavioural Experiments; Figures 2-3; Results.
Editorial notices
No editorial notice surfaced in the Scite/primary-record checks used for this record; this is not a comprehensive clean-bill certification.
Funding
DFG SFB1372/GRK1885; DAAD; Lower Saxony Nano-Energieforschung stipend; ERC QuantumBirds 810002; Projekt DEAL open access.
Conflicts of interest
Authors declare no conflict of interests.

Reviews to read alongside

Related syntheses and proposals in the separate review collection. These are topical reading links, not additional independent experiments.

Original publication

Bo Leberecht; Dmitry Kobylkov; Thiemo Karwinkel; Sara Döge; Lars Burnus; Siu Ying Wong; Shambhavi Apte; Katrin Haase; Isabelle Musielak; Raisa Chetverikova; Glen Dautaj; Marco Bassetto; Michael Winklhofer; P. J. Hore; Henrik Mouritsen. Broadband 75-85 MHz radiofrequency fields disrupt magnetic compass orientation in night-migratory songbirds consistent with a flavin-based radical pair magnetoreceptor. Journal of Comparative Physiology A. 2022;208(1):97-106. doi:10.1007/s00359-021-01537-8.

Plain-text record