A fascinating application of thematic mapping techniques to commercial whaling, by eminent American zoologist Charles Haskins Townsend (1859-1944).
Townsend’s nearly 55-year career spanned both the public and private sectors. From 1883-1902 he held a variety of positions in the United States Fish Commission, then spent the next 35 years as Director of the New York Aquarium. He also “wrote extensively on fisheries, whaling, fur seals, deep-sea exploration and zoology, including ornithology and herpetology.” (Wikipedia) A particular field of interest was whaling, and late in his career he made significant contributions as both a researcher and, in 1928, as a founding member of the Council for the Conservation of Whales (He soon broke with the Council and adopted a more conservative stance in an effort to remain on good terms with the whaling industry, which was an essential source of data for his research.)
Likely in 1929 or 1930 Townsend undertook a remarkable project, being the compilation of raw data contained in whalers’ logbooks held in the collections of the New Bedford Public Library, New Bedford Whaling Museum, and other public and private repositories.
“[These logbooks] represented a supply of hitherto unused records available for additional information on this subject [i.e., the distribution and seasonal movements of whales]. The logbooks, hundreds in number, show clearly where the nineteenth century whaler made his catches of sperm, bowhead, right, gray, humpback and occasionally other species. A little experimental plotting on a chart indicated that much could be learned of distribution by extensive work of this sort and by using a separate chart for each species. It was also evident that by using a distinctive color for each month’s captures, the movements of whales would be apparent to a considerable degree. The plotting of the positions of whaleships on days when whales were taken, threw light on the locations and dimensions of the “whaling grounds” frequented by the old-time whalers as well as the seasons when they were visited.” (Townsend, “Where the Nineteenth Century Whaler Made His Catch.” Bulletin of the New York Zoological Society, vol. xxxiv, no. 6 (1931), p. 173)
In all Townsend’s team reviewed hundreds of logbooks recording some 1665 voyages between 1761 and 1920 that brought in no fewer than 53,877 whales. The data were plotted on a set of four thematic maps showing the worldwide distribution of catches by American whaling vessels over 160 years. This is not the first such effort to plot whaling data based on ship’s logs–the first was Matthew Fontaine Maury’s 1851 Whale Chart—but Townsend’s data set was vastly larger and the resulting maps far more informative.
Offered here is a complete set of Townsend’s four maps, which were issued as illustrations to his 1935 article “The Distribution of Certain Whales as Shown by Logbook Records of American Whaleships” (Zoologica vol. XIX no. 1 (1935), pp. 3-50). The physical condition of the present set, folded but with untrimmed margins, suggests that they were never bound. The maps are as follows:
DISTRIBUTION OF THE SPERM WHALE BASED ON LOGBOOK RECORDS DATING FROM 1761 TO 1920[:] CHART A—APRIL-SEPTEMBER, INCLUSIVE
DISTRIBUTION OF THE SPERM WHALE BASED ON LOGBOOK RECORDS DATING FROM 1761 TO 1920[:] CHART B-OCTOBER-MARCH, INCLUSIVE
CHART C[:] DISTRIBUTION OF NORTHERN AND SOUTHERN RIGHT WHALES BASED ON LOGBOOK RECORDS DATING FROM 1785 TO 1913
CHART D[:] DISTRIBUTION OF BOWHEAD AND HUMPBACK WHALES BASED ON LOGBOOK RECORDS—MOSTLY 19TH CENTURY
Each map uses as its base the same Mercator map of the world, with coverage from 60 North to 60 South latitude. Superimposed on the maps are thousands of tiny circles, each representing “the position of a whale-ship on a day when one or more whales were taken.” The circles are color coded by month, making it possible to follow the movements and migrations of whale populations over the course of the year.
The result—attractive, easily read, and deeply informative–is a classic of data visualization. For example, each map shows quite clearly for example the heavy concentration of catches in distinctive “whaling grounds” in the Indian and North and South Atlantic Oceans. Likewise, Chart A and Chart B show quite clearly the annual migration of sperm whales from their more northerly Summer feeding grounds to more equatorial and southerly grounds in the Winter.
Townsend’s maps are very rare: I find no record of others having appeared on the antiquarian market, either separately or bound in as plates to volume XIX of Zoologica.