No abstract

The aim of this study was to test the use of measures obtained from freelisting as possible surrogates of the harvest rate of game species. For this purpose, we interviewed 100 rural and urban hunters in southwestern Amazonia to obtain the frequency of citations of each hunted species through freelisting and gather information on the number of individuals hunted per species in the last five hunting events through hunting recalls. We assessed the relationship between the percentage of records per species by each method through a generalized linear model, and then compared the predicted values obtained from this model with the values observed in our dataset using Pearson’s correlation. During freelisting, forty-three taxa were listed in 608 citations as hunted by the informants. Freelisting provided data on around twice the number of species obtained from recalls. During the last five hunting trips, urban hunters reported the hunting of 164 individuals of 18 species, representing 54.5% of the freelisted species. Rural hunters caught 146 individuals of 21 species, 60.0% of the freelisted species. We found a strong logistic relationship between the harvest rates, i.e., percentage of individuals hunted per species from recalls, and the freelisting percentage citations of game species, with the estimated and observed values of harvest rates highly matching (Pearson's R = 0.98, p < 0.0001). The freelisting method allowed a good estimate of the composition and the harvest rates of hunted species. The formula produced in this study can be used as a reference for further studies, enabling researchers to use freelisting effectively to assess the composition of hunted species and to address the difficulty of obtaining reliable data on species harvest rates in tropical forests, especially in short-term studies and contexts in which hunters distrust research.

Effective estimation of wildlife population abundance is an important component of population monitoring, and ultimately essential for the development of conservation actions. Diurnal line‐transect surveys are one of the most applied methods for abundance estimations. Local ecological knowledge (LEK) is empirically acquired through the observation of ecological processes by local people. LEK‐based methods have only been recognized as valid scientific methods for surveying fauna abundance in the last three decades. However, the agreement between both methods has not been extensively analysed. We compared concomitant abundance data for 91 wild species (mammals, birds and tortoises) from diurnal line transects (9,221 km of trails) and a LEK‐based method (291 structured interviews) at 18 sites in Central and Western Amazonia. We used biological and socioecological factors to assess the agreements and divergences between abundance indices obtained from both methods. We found a significant agreement of population abundance indices for diurnal and game species. This relationship was also positive regardless of species sociality (solitary or social), body size and locomotion mode (terrestrial and arboreal); and of sampled forest type (upland and flooded forests). Conversely, we did not find significant abundance covariances for nocturnal and non‐game species. Despite the general agreement between methods, line transects were not effective at surveying many species occurring in the area, with 40.2% and 39.8% of all species being rarely and never detected in at least one of the survey sites. On the other hand, these species were widely reported by local informants to occur at intermediate to high abundances. Although LEK‐based methods have been long neglected by ecologists, our comparative study demonstrated their effectiveness for estimating vertebrate abundance of a wide diversity of taxa and forest environments. This can be used simultaneously with line‐transect surveys to calibrate abundance estimates and record species that are rarely sighted during surveys on foot, but that are often observed by local people during their daily extractive activities. Thus, the combination of local and scientific knowledge is a potential tool to improve our knowledge of tropical forest species and foster the development of effective strategies to meet biodiversity conservation goals.