Decor image by Antonio Vasilijevic
Tb eNEWS - 10 - April 2017 - newsletter cover
Tb eNEWS - 10 - April 2017

IN FOCUS: Africa’s first marine Transfrontier Conservation Area

Hands Across Borders

Planning for the future survival of coral reefs in the Grenadines

TRANSBOUNDARY CONSERVATION >> Global inventory >> Methodology
Methodology of 2007 UNEP-WCMC's global inventory of TBPA

To qualify for inclusion in this TBPA 2007 list the protected area (PA) had to:

  - conform to the IUCN definition of a protected area (IUCN, 1994) and be designated either under national legislation or within international or regional conventions or initiatives (e.g. World Heritage Convention, UNESCO Programme on Man and the Biosphere, etc.);

 - be included in the World Database on Protected Areas as a georeferenced entity - either polygon outlining PA boundary or point indicating the centroid (latitude/longitude) of the PA. and
    -- be adjacent to an international boundary and adjacent to a protected area in a neighboring country (1st-order transboundary neighborhood) or
    -- be directly adjacent to (or overlap partially and/or entirely with) 1st-order transboundary sites (these sites constitute 2nd-order component of IAPA complexes) identified above or
be contained by 2nd-order sites (these sites are also considered as a 2nd-order component of IAPA complexes).

In addition to sites identified on the basis of these criteria through the GIS analysis, a number of non-adjacent couples or groups of sites are documented in Zbicz (2001) and Mittermeier et al. (2005). Cooperation between countries in managing these sites was evaluated on a case-by-case basis and relevant sites have been included into the list.

Estimation of the total area extent of a particular transboundary complex was made on the basis of the GIS analysis, which avoided double-counting of territories assigned by two or more designations, e.g. by national legislation and under international convention. Therefore the total size of a particular internationally adjoining protected area is often smaller than the sum of territories of individual sites combining transboundary complex. For TBPA/IAPA complexes represented by a single site (or by non-overlapping sites) on each side of the international boundary only the official statistic on PA area was applied. Similarly, for TBPA/IAPA complexes lacking data on site boundaries (i.e. polygon data) official information on PA area was used wherever the GIS-based estimate of a total area for a group of sites exceeded the sum of officially documented area for individual PA's in this group. Relevant calculations and checking were applied separately for every IAPA part belonging to particular country. Total area of TBPA (that includes sites belonging to two or more neighboring countries) was calculated as a sum of relevant national parts of a particular TBPA.


Total Area of TBPA by Region (30.04.2007)

Region TBPA area, km2
North America 1,511,627.08
Central and South America 1,424,697.66
Europe 188,153.30
Africa 931,617.95
Asia 570,505.86
Global 4,626,601.85