3.2 Global distribution of tracking studies
Overall, 49 countries across six continents are represented in the 162 studies. Studies were not evenly distributed among countries, and 51 studies were conducted in just four countries: Costa Rica (9% of studies), Brazil (8%), USA (8%) and Panama (6%) (Fig 2). More studies were conducted in tropical and sub-tropical than in temperate regions; this is illustrated in the two most well studied taxonomic groups birds (studies in tropical/sub-tropical regions 64% vs. temperate 36%) and mammals (tropical/sub-tropical regions 83% vs. temperate 17%).
The number of studies conducted within, and outside protected areas, varied by region. The percentage of studies conducted within protected areas was highest in Central America and lowest in Europe (see Supplementary Material 1; Figure 2). This is reflected in the research sites used in Central American studies; nine studies from Panama and 13 studies from Costa Rica were in protected areas. The proportion of studies that addressed the ability of species to disperse seeds also differed among regions. For example, 50% of all tracking studies were conducted in the Americas but only 27% of all seed dispersal studies (see Supplementary Material 1; Figure 2).