As most birders know, only female crows incubate. That is, if a crow is sitting in a nest incubating, it is almost invariably a female. A female corvid stays very close to the nest often brooding over the nestlings, probably until the young gains sufficient thermoregulation ability. The male brings food to his mate and nestlings in addtion to that for himself during this period. Thus, it is presumed that the work load of a breeding male is considerably large. (This is also true with other corvids like magpies and jays)
Based on the observation of a number of breeding crow pairs, I have found it possible to tell apart sexes of crows to a considerable extent. I understand very well that the accuracy has to be limited depending on observation and photographing conditions and that I have to keep in mind that I shouldn't make premature identifications if sufficient observation and supporting evidences/data are not available.
Bearing the above-mentioned limitations in mind, I would like to show you how crows can be visually sexed (with supporting behavioral observations) in some cases.
The photo is that of a female Carrion Crow incubating.
Based on the observation of a number of breeding crow pairs, I have found it possible to tell apart sexes of crows to a considerable extent. I understand very well that the accuracy has to be limited depending on observation and photographing conditions and that I have to keep in mind that I shouldn't make premature identifications if sufficient observation and supporting evidences/data are not available.
Bearing the above-mentioned limitations in mind, I would like to show you how crows can be visually sexed (with supporting behavioral observations) in some cases.
The photo is that of a female Carrion Crow incubating.
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