What are Latilongs?
|Latilongs are the rectangular areas between adjacent meridians
of longitude and parallels of latitude. The average dimensions of each latilong
are 47 miles (76km) wide and 69 miles (111 km) long, resulting in an average
area of 3200 square miles (8436 sq. km).
A major advantage of using latilongs in biogeographic studies is that they are unchanging units based on a global system. This allows for long-term studies and conformity of national and international scope. The Breeding Bird Survey of the U.S. Fish and Wildlife Service is based on latilong grids across North America. Latilong maps allow distribution patterns to be presented in concise and easily readable form. Latilongs are readily identifiable on most maps. The use of latilong mapping in biogeographical studies is increasing worldwide.
Drawbacks to using latilong mapping include the fact that they vary in size from north to south, with about a 1.3% increase per latilong as they get closer to the equator. Furthermore, state boundaries do not always conform to meridians and parallels. This results in latilongs much smaller than 3200 square miles, effecting several of Idaho's latilongs. Finally, latilongs are quite large resulting in a scale too course for small geographic areas.
The Idaho bird distribution study uses the U.S. Fish and Wildlife Services system to identify and number Idaho's latilongs. Twenty-eight latilongs are assigned to Idaho and are numbered from 1, along the Canadian boarder, to 28 in the southeast corner of the state (map at right). Officially these are numbered 33001 to 33028 using the U.S. Fish & Wildlife Service system. Again, we simply use 1 to 28...
Latilongs 3, 6, 7, 9, 10, 14, 15, & 16 include significant area outside the Idaho state boundaries; only the portion of the latilong within the state boundary is considered for this project. On the other hand, note that a small area of Idaho west of latilong 11 is found in the Baker, Oregon latilong. This area is northwest of Weiser and includes the Olds Ferry and Mineral areas. Records from this area are included in Idaho latilong 11 for the maps, but are marked as technically occurring in the Baker, Oregon latilong in the database.