Logging within protected areas: Spatial evaluation of the monarch butterfly biosphere reserve, Mexico

Abstract

Depending on the particular sociopolitical situation of a country or region, as well as the degree of dependence that a population has on its vegetation resources, both forest management or designating protected areas may serve as effective policies to protect highly valuable forest areas in the long term. Biosphere Reserves, where forest management is allowed in buffer zones but completely restricted in core zones, are an important category in this regard. They are of special importance in developing countries where a high dependency on natural resources as source of subsistence is still prevalent. This paper analyzes the effectiveness of authorized logging versus strict protection in preserving the forest cover within the Monarch Butterfly Biosphere Reserve (MBBR), in its portion in Michoacán state, México. This protected area is crucial for the preservation of the migratory monarch butterfly, and has been negatively impacted by logging and other activities. Data on logging permits from 1993 to 2006 were extracted and spatially digitized from all the officially approved Forest Management Programs (FMP) of the MBBR’s communities. Based on the delimitation of authorized logging areas, an analysis of the processes of change in forest cover was made, by means of spatial and statistical comparisons among land tenure units (LTU) with and without FMP. Statistical analyses found no significant differences of loss rates of conserved canopy cover forest between LTU with and without FMP, nor with other change processes such as recovery and re-vegetation. However, deforestation due to land use changes was significantly greater in LTU lacking FMP, although this involved a relatively small area. Spatial analyses clearly showed where the forest disturbance is concentrated, and that it is mostly caused by illegal logging and by inadequate management (extraction of timber beyond the authorized period, and forest fragmentation led by individual use of communal land). The results show that the total disturbance observed from 1993 to 2006 (5239 ha) is explained in 61% by illegal logging, 33% by extemporaneous authorized extractions and only 6% by authorized logging during the scheduled period. Thus FMP are an effective option for maintaining the forest cover in the reserve. The procedure used in the present analysis can be an effective and accessible monitoring tool, which can be used by officials responsible for forest use to supervise the strict application of logging licenses, and to give support to decision making when renewing, redesigning or revoking logging licenses.