Seasonality of births in nineteenth-century urban Tasmania
Gunn, P.A.
Human Biology 64(1): 51-65
1992
ISSN/ISBN: 0018-7143 PMID: 1582648 DOI: 10.2307/41464250Document Number: 318624
Monthly data on 16,677 births in the Hobart registration district in the English colony of Van Diemen's Land (Tasmania) between 1839-59 were applied to the circular goodness of fit test and the Maag's U2 to prove that births were not seasonal as often believed. Also examined were 19th century data from the rural districts of Oatlands and Bothwell which demonstrated patterns of birth seasonality. The monthly birth distributions for the Hobart registration district were not seasonal. Even in the years when there was an indication of seasonality 91840-44 and 1955-59), no consistent pattern of monthly distribution if births emerged, which supported the general interpretation that the births were not seasonally distributed. The observed pattern of births in Hobart differed from that of the 2 rural districts. Both urban and rural data indicated apparent seasonality of births for farming families but not for families of farm laborers. Occupation had more importance in seasonality than the direct effects of climate. For example, the only industrial groups that exhibited any seasonality at all in the urban district were those that depended on the demands of the climate--farming, the maritime trade (but not from coastal whaling and fishing), and dealing in foodstuffs (most were butchers). Yet seasonality was marginal. No significant differences in seasonality of births existed between the classes. Seasonal distribution of urban births did not parallel the seasonality patterns observed in 20th century Hobart. The 20th century seasonality patterns occurred because women had contraceptive technology available to time births. The mid-19th century distribution of births pattern in Hobart did not match either that of mid-10th century rural districts or that of the 20th century.