Assessing spatial dispersion, abundance, and conservation perspectives of Military MacawAra militarispopulations in Mexico

Abstract

Summary The preservation of Military Macaw Ara militaris in Mexico required the implementation of a nationwide assessment evaluating its vulnerability using IUCN criteria. With the combined effort of several institutions, the abundance, location, dispersion, habitat availability, and climatic conditions of areas occupied by the species were determined. Although the species’ extent of occurrence is extensive (263,919 km2) only 29% of this constitutes area of occupancy. Published estimates indicate a series of isolated populations containing from four macaws to 215. Macaws occurred in 35 populations in four regions of 16 states containing an estimated 1,563–3,263 macaws; lower than required for long-term viability. Within regions, neighbouring populations were separated by an average of 68 km. The extent of occurrence is heterogeneous, and macaws inhabit areas that differ in elevation, precipitation, temperature, and forest cover. Higher local abundances occur in landscapes where annual precipitation is ≥1,100 mm, and primary forest availability ≥1,800 km2. Although the existence of undetected macaw groups in Mexico is possible, these are likely to contain only small numbers of individuals, as most detected areas with macaws contain less than 40 individuals, and larger concentrations are more likely to be noticed due to their conspicuous behaviour. The species is threatened primarily by its low overall abundance, fragmented distribution, and forest loss around populations with the highest abundance. With the information generated, it is possible to design and implement specific management and conservation strategies at different geographic scales for the recovery and maintenance of the species in Mexico. It is necessary to strengthen collaborative programmes among conservation organizations, government agencies, and local communities in each region of the country to organize and finance community-based actions such as monitoring, habitat restoration, protection from poaching and the creation of a network of conservation corridors and macaw reserves focused on conservation.

The Preclassic military macaw (Ara militaris) from the Cueva de Avendaños (Chihuahua, Mexico) was not locally procured

“…The actual climate in the Cueva de Avendaños area is temperate and semi‐dry with a temperature range between 12°C and 18°C and a precipitation range between 400 and 700 mm (INEGI, 2005). These climate particularities are very important because the variables with the greatest percentage contribution for geographic and paleobiogeographic distribution models are the precipitation variables, and the presence of high local abundances of military macaw occur in landscapes where the annual precipitation is ≥1100 mm (Monterrubio‐Rico et al, 2021).…”

“…In particular, a highest dry period with low lake levels is suggested between 2000 and 1000 cal BP (Wanner et al, 2008). The reduction of forest cover in several tropical and subtropical areas is related to these changes in precipitation and cool weather, where the precipitation is an important variable for the presence of military macaw populations (Monterrubio‐Rico et al, 2021). However, the influence of human activities during this period is not clearly defined (Aragón‐Moreno et al, 2018; Metcalfe, 2006; Metcalfe et al, 2015; Polyak & Asmerom, 2001).…”

“…The military macaw's current and historical presence data were obtained to produce a biogeographical distribution model. The sources were the Global Biodiversity Information Facility (GBIF, 2021), Integrated Digitized Biocollections (iDiGBiO, 2021), CONABIO (National Commission for the Knowledge and Use of Biodiversity, Navarro‐Sigüenza et al, 2018), scientific collections, and literature records (Jiménez‐Arcos et al, 2012; Monterrubio‐Rico et al, 2021; Rivera‐Ortíz et al, 2013, 2020). These data were refined using known current and historical distributions, with a buffer of 0.5° (55.5 km), and present data that did not fall within this distribution were eliminated.…”