During the breeding migration of Bufo bufo in 1971 the number of females was counted, killed by traffic on an asphalt road with about 10 cars/hour. By counting egg-strings the total number of females was estimated too. By comparing both data it appeared that 30% of the females passing the road were run over. For the males a similar percentage is expected.

Hibernation behaviour of six common toads Bufo bufo was studied. Transmitters, generating pulses with a temperature dependent repetition rate, implanted in the toad's abdominal cavity, were used to measure the body temperature. Measurements of body temperature and soil temperature at various depths were used to establish the hibernating depth. All toads moved vertically between a few preferred depths and hibernating depth appeared to vary for individual toads. Upward movements mostly were apparent reactions on changes of the soil temperature gradient at the depth of the toad.

Using hematoxylin-stained cross-sections of phalanges of captured and recaptured toads it is shown that in adult Bufo bufo from the Netherlands year rings are formed. It is concluded that these year rings can be used for age determination, if the degree of resorption of initially formed year rings is known.

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