An estimated 15,000 jaguars remain in the wild. There are only 6000 jaguars in north and central America, half of which are found in the Calakmul region, which includes the southern Yucatan of Mexico and surrounding areas of Belize and Guatemala. It is estimated that there 500 jaguars in the Calakmul Biosphere Reserve. This is the second largest population north of the Amazon.

The Calakmul Biosphere Reserve is an extremely important wildlife corridor that is crucial for migrating birds and animals with extensive ranging patterns such as jaguar and tapir. Over the last 10 years the reserve has experienced a notable reduction in rainfall. Monitoring data on birds, bats, herpetofauna, butterflies, ungulates, felids and primates are being used to evaluate the impact of climate change and changing rainfall patterns on the abundance, ranging and diversity of fauna to help determine when and where mitigation should be used to restore water sources. Data are also used to assess the efficacy of a range of sustainable development projects with buffer zone communities designed to minimise forest encroachment. There are specialist studies on jaguar and their preferred prey.

Large mammal density at Calakmul Biosphere Reserve is very high and the forest is one of the last remaining strongholds of endangered mammals such as spider monkeys, jaguar and tapir. Although these species are not hunted, indigenous people are allowed to hunt other large mammals such as peccary and deer (which are the preferred prey of jaguar and puma). The aim of the large mammal research project is to investigate the relationship between habitat characteristics and large mammal abundance and ranging, and to investigate the impact of hunting of preferred prey species on the abundance and distribution of felids. Mammal abundance data will be collected along a series of forest transects using distance sampling (based on visual sightings of more commonly encountered species such as primates) and patch occupancy sampling (based on tracks and signs of more elusive species such as tapir and jaguar). Additional data will be collected using camera traps enabling comparison of density estimates produced by the different types of surveys. The survey transects are distributed across a wide range of forest habitat types and each transect contains a number of 20m x 20m habitat survey plots. In each of these plots, tree species will be identified, and DBH and tree height will be measured. Large mammal data from each transect can then be related to mean habitat characteristics for the transect and comparisons between mammal abundance and habitat variables may be investigated.