Documented reports of unusual catfish behaviour in the run-up to the 1855 Edo earthquake in Japan prompted a number of scientific studies. In one study, catfish movements were observed over a 16-year period. The researchers found that the catfish behaved unusually in 27 out of 87 cases (30%) in earthquakes with a magnitude of 3 or more. In one case, intensified catfish activity was observed between eight and four days before a magnitude 5.9 quake. No precise details have been published on how the 30% 'success rate' was determined and whether such warnings were effectively followed up.
Source: Ikeya, 2004