Kaziranga. Females have heat periods at intervals of 40-50 days.
The nature of the vegetation and the terrain in Kaziranga thwart the use of most methods commonly used to determine wildlife populations. Counting animals from an airplane was tried on 24 March 1949, but the grass cover was so dense that only a few animals could be counted. A 6-seater airplane was used during this census and was not flown below a height of about 400 feet. Perhaps the use of a lighter airplane would provide a relatively accurate and inexpensive means of counting most of the rhino.
Kaziranga. Rhino are relatively difficult to sex in the field, except in the case of females with young. When a rhino urinates, a keen observer can sex individuals accurately. Other their observing their private parts, there appears to be no fool-proof criterion. However, some claim to be able to differentiate the sexes by the size or shape of the horn, others maintain that the males have a thicker neck than the females. Not substantiated by my observations.
Kaziranga. Rhino are relatively difficult to sex in the field, except in the case of females with young. When a rhino urinates, a keen observer can sex individuals accurately. Other their observing their private parts, there appears to be no fool-proof criterion. However, some claim to be able to differentiate the sexes by the size or shape of the horn, others maintain that the males have a thicker neck than the females. Not substantiated by my observations.
Almost invariably when a female was accompanied by a calf, other females with calves could be located nearby. On March 14, we observed 5 females within a radius of 200 yards, all accompanied by a young. On other occasions, up to 20 adult rhino would be tallied at a stretch, then within a relatively short time several females with calves would be observed, one pair right after another. Whether or not there is a definite social relationship among females with young needs investigation.
Kaziranga. Calf stays with the mothers for almost 4 years. It appears that the maximum rate of increase in the wild state would be little more than one calf per female every 5-6 years.
Kaziranga. The young attain puberty at about 4 ? years of age.
