Original provider: Wildlife Conservation Society

Dataset credits: Wildlife Conservation Society

Abstract: The Wildlife Conservation Society (WCS) has digitally captured the Townsend Whaling Charts that were published as a series of 4 charts with the article titled "The distribution of certain whales as shown by logbook records of American whale ships" by Charles Haskins Townsend in the journal Zoologica in 1935. The 4 charts show the locations of over 50,000 captures of 4 whale species; sperm whales (36,908), right whales (8,415), humpback whales (2,883) and bowhead whales (5,114). Capture locations were transcribed from North American (“Yankee”) pelagic whale vessel log books dating from 1761 to 1920 and plotted onto nautical charts in a Mercator projection by a cartographer. Each point plotted on the charts represents the location of a whaling ship on a day when one or more whales were taken and is symbolized by month of the year using a combination of color and open and closed circles. Townsend and his cartographer plotted vessel locations as accurately as possible according to log book records. When plotting locations on an earlier sperm whale chart published in 1931 the cartographer spaced points where locations were very dense, "extending areas slightly" for a number of whaling grounds. However, for charts in preparation at this time, Townsend states that "this difficulty is avoided by omitting some of the data, rather than extend the ground beyond actual whaling limits." We assumed that this statement refers to the 1935 charts but there is still some question as to whether the cartographer did in fact space locations and thus expand whaling grounds.

Purpose: This dataset provides point features that represent the historical locations of right whale catches taken by North American pelagic whaling vessels between 1761 to 1920. Points were derived from 4 charts that were first scanned on a large format scanner at a resolution of 200 dpi. The charts were then georeferenced in the native projection of the charts, the Mercator projection, using GIS software (ESRI ArcView 3.2). Each vessel capture location plotted on the charts was then digitized as a point feature and attributed with the month of capture. One GIS file (ESRI shapefile) was then created for each whale species represented by the charts; sperm whale, right whale, humpback whale and bowhead whale.

Digitizing errors include missed points, particularly from areas of dense chart locations, and incorrect assignment of month of capture because of difficulty distinguishing between chart colors. However to limit these errors multiple checks of digitized and chart locations were made and color enhancements of chart scans were used to ensure correct month assignments. Overall we are confident that at least 95% of catch locations have been digitized and that at least 95% of month attributes are correct.

For full resolution digital copies of the Townsend charts please contact Gillian Woolmer (gwoolmer@wcs.org).

Supplemental information: [2023-01-31] The year of the date was changed from 1913 to 1849, the midpoint of the time range of the data.

WCS digitized the Townsend whaling charts in 2002 using ArcView 3.2 from ESRI. The information WCS has captured for each point location is the whale species (based on the chart) and the month, based on the chart point symbol. Exact dates and number of whales taken was not possible to determine. Right whale captures were separated into northern and southern right whale species, based on their geographic location.

Since time, count, day, and year were not available, "00:00:00," 1, 1, and 1913 were used, respectively. Only month is available.

Take a looks at the Harvard Map Collection's interactive exhibit 'Embellishing the Map,' which explores the myriad varieties and uses of embellishments found on the library's extraordinary collection of maps.This exhibition presents maps chosen from the Harvard Map Collection that display how European cartographers, mainly from the Low Countries of the 16th and 17th centuries, embellished maps with a variety of illustrative, non-cartographic elements. With echoes of the classical world’s anxiety of the “horror vacuii” (fear of empty spaces), the uncharted and unknown spaces are populated with sea creatures and animals, from the mythic and fantastic to the zoologically accurate, and many varieties of ships plying the open seas. All in their natural habitat, which is to say located on the land and seas of the map, not as artistic embellishments in cartouches or title panels (something for another exhibition, perhaps). The sources for the cartographic fauna run the gamut from classical sources (the histories of Herodotus and Pliny the Elder), Medieval bestiaries and compendiums of the natural world (Hortus Sanitatis), to accounts from the ever peripatetic explorers. The maps are presented in loosely geographic order, beginning (where everything begins) with the heavens, then, after a medieval view of the known world, moves from the Western Hemisphere eastward to the Pacific Ocean. Besides the few modern, more thematic maps that have been included for contrast, chronologically this exhibition effectively ends before the ascendancy of the Royally sponsored French cartographers of the 18th century. The maps of Delisle, Bellin, d’Anville and the distinguished Cassini dynasty migrate the sea creatures, animals and ships to the pages and articles of Diederot’s grand Encyclopedia. What now is presented on the map reflects the science of cartography and measurement reigning supreme, not alas (as seen in the 1541 map “Tabula noua partis Africae”), a King riding a bridled Sea Carp!

The 1966 polygons included in this data release represent the main body portion of the 37 named glaciers of Glacier National Park (GNP) and 2 named glaciers on the U.S. Forest Service’s Flathead National Forest land. This is a subset of the original mapping effort derived from 1:24000 scale mapping of named glaciers and permanent snowfields within Glacier National Park, Montana which were digitized by Richard Menicke (Glacier National Park) and Carl Key (U.S. Geological Survey) in 1993. These data are based on USGS 7.5 minute quadrangle mapping published from 1966 through 1968 which were the result of the earliest park-wide aerial surveys of snow and ice features in GNP. Examination of the aerial photographs shows that seasonal snow was present at some of the glaciers, limiting the ability of the 1966-1968 cartographers to see and map the glacier ice margins. This resulted in some smoothed and generalized outlines of the glaciers where the cartographers were likely guessing where the ice margins were under the snow. In addition, some photographs show exposed glacier margin ice with irregular patterns that are not represented by the mapped ice margin. It appeared that the original cartographers used a more generalized outline for the glaciers and were not concerned with small scale ice features even when they were evident in the photographs. Despite the generalized nature of the glacier outlines, which were also limited by mapping technology and standards of the time, the dataset represents the baseline for the glacier margins derived from aerial photography. In several cases, because of the generalized nature of the 1966-1968 mapping, a glacier perimeter did not seem as if it reflected likely location in the basin topography. In these cases the original USGS aerial imagery was referred to for verification and revision if the error seemed significant. Specifics of margin revision are detailed in attribute files for those glaciers that warranted change as part of the time series analysis conducted by Dan Fagre and Lisa McKeon (USGS) in February - August, 2016. For each glacier, determination of what constituted the "main body" was made in accordance with USGS criteria outlined in Supplemental Information section of the xml file and some disconnected patches were eliminated in the interest of keeping this analysis strictly to glacier main bodies.