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Definitions of the American Indian and Alaska Native Geographic Areas

In preparation for the 2010 Census, the Census Bureau offered officials from federally and state recognized tribes, Alaska Native Villages and Alaska Native Regional Corporations the opportunity to review and update the geographic areas below.

Detailed information about TSAP and the State Reservation Program is available on the TSAP webpage.

Alaska Native Village Statistical Areas (ANVSAs)

ANVSAs are statistical geographic entities representing permanent and/or seasonal residences of Alaska Natives who are members of, or receive governmental services from, the defining Alaska Native village (ANV).  ANVSAs are intended to include only an area where Alaska Natives, especially members of the defining ANV, represent a substantial proportion of the population during at least one season of the year.

Alaska Native Regional Corporations (ANRCs)

ANRCs are corporate entities organized to conduct both for-profit and non-profit affairs of Alaska Natives pursuant to the Alaska Native Claims Settlement Act.  ANRCs have legally defined boundaries that subdivide all of Alaska into twelve regions (except for the area within the Annette Island Reserve).  The non-profit officials of ANRCs review their legal boundary and may, in the absence of participation by the Alaska Native village official, act as proxy in the delineation of ANVSAs in their regions.

Oklahoma Tribal Statistical Areas (OTSAs)

OTSAs are statistical areas that were identified and delineated by the Census Bureau in consultation with federally recognized American Indian tribes based in Oklahoma.  An OTSA is intended to represent the former American Indian reservation that existed in Indian and Oklahoma territories prior to Oklahoma statehood in 1907.  OTSAs are intended to provide geographic entities comparable to the former Oklahoma reservations so that statistical data can be viewed over time.  OTSAs were referred to as Tribal Jurisdiction Statistical Areas (TJSAs) in the 1990 Census data products.

OTSA Tribal Subdivisions

Tribal subdivisions are internal units of self-government and/or administration that serve social, cultural, and/or economic purposes.  Federally recognized Oklahoma tribes with OTSAs may identify and delineate an administrative subdivision within their OTSA.  Although some tribes have more than one type of subdivision, tribes may identify only one type of subdivision on their OTSA for Census Bureau purposes.

Tribal Designated Statistical Areas (TDSAs)

TDSAs are statistical geographic entities identified and delineated for the Census Bureau by federally recognized American Indian tribes that do not currently have an American Indian reservation and/or off-reservation trust land.  A TDSA is intended to encompass a compact and contiguous area that contains a concentration of individuals who identify with the delineating federally recognized American Indian tribe.  TDSAs are also intended to be comparable to American Indian reservations within the same state or region and provide a means for reporting statistical data for the area.

Tribal Census Tracts and Tribal Block Groups

Tribal census tracts and tribal block groups are statistical geographic entities defined by the Census Bureau in cooperation with tribal officials, unique to and within the boundaries of federally recognized American Indian reservations and/or off-reservation trust lands.  Tribal census tracts and tribal block groups allow for an unambiguous presentation of tract and block group level data specific to the reservations and off-reservation trust lands without the imposition of state or county boundaries, and provide a geographic framework for the tabulation and presentation of statistical data for communities within the reservation.   Tribal census tract identifiers differ from standard census tract identifiers.  The tribal census tract code is alpha-numeric and always begins with a "T."  For example, a reservation with 2 tribal census tracts would have tract codes T001 and T002.  Tribal block groups nest within tribal census tracts and are identified by a single capital letter from "A" through "K" (except for the letter "I") following the tribal tract identifier.  Tribal block groups are identified as "T001A", "T001B", continuing until every tribal block group within that tract is labeled.

Census Designated Places (CDPs)

CDPs are statistical geographic areas representing closely settled, unincorporated communities, which are locally recognized and identified by name.  They are statistical equivalents of incorporated places with the primary differences being the lack of both a legally defined boundary and an active, functioning government.  A CDP generally consists of a contiguous area with a concentration of housing and commercial structures similar to that of an incorporated place of similar size.  CDPs are delineated on reservations by the Census Bureau in collaboration with tribal officials.  Tribal officials may also work with counties or regional agencies to define CDPs for tribal communities completely off their reservations.

State American Indian Reservations (SAIRs)

State American Indian reservations are the legally defined reservations of state-recognized tribes.  The reservations of state-recognized tribes are established by treaty, statute, executive order and/or court order, and represent area over which the tribal government of a state-recognized American Indian tribe may have governmental authority.  The Census Bureau works with a governor appointed state liaison to obtain the name and boundary for each state-recognized American Indian reservation.

State Designated Tribal Statistical Areas (SDTSAs)

SDTSAs are statistical geographic areas identified and delineated for state recognized tribes that are not federally recognized and do not have an American Indian reservation or off-reservation trust land.  The Census Bureau works with a governor appointed state liaison to delineate statistical areas for state-recognized tribes.  SDTSAs do not cross state lines and are limited to the state in which the respective tribe is officially recognized.  SDTSAs provide state recognized tribes without reservations statistical data for a geographic area that encompasses a substantial concentration of tribal members.  SDTSAs were called State Designated American Indian Statistical Areas (SDAISAs) for Census 2000.


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