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.

Given the ongoing environmental degradation from local to global scales, it is fundamental to develop more efficient means of gathering data on species and ecosystems. Local ecological knowledge, in which local communities can consistently provide information on the status of animal species over time, has been shown to be effective. Several studies demonstrate that data gathered using local ecological knowledge (LEK)‐based methods are comparable with data obtained from conventional methods (such as line transects and camera traps). Here, we employ a consensus analysis to validate and evaluate the accuracy of interview data on LEK. Additionally, we investigate the influence of social and bioecological variables on enhancing data quality. We interviewed 323 persons in 19 villages in the Western and Central Amazon to determine the level of consensus on the abundance of hunted and non‐hunted forest species. These villages varied in size, socio‐economic characteristics and in the experience with wildlife of their dwellers. Interviewees estimated the relative abundance of 101 species with a broad spectrum of bioecological characteristics using a four‐point Likert scale. High consensus was found for species population abundance in all sampled villages and for 79.6% of interviewees. The village consensus of all species abundance pooled was negatively correlated with village population size. The consensus level was high regardless of the interviewees' hunting experience. Species that are more frequently hunted or are more apparent had greater consensus values; only two species presented a low consensus level, which are rare and solitary species. We show in our study in the Amazon that information gathered by local peoples, Indigenous as well as non‐Indigenous, can be useful in understanding the status of animal species found within their environment. The high level of cultural consensus we describe likely arises from knowledge sharing and the strong connection between the persons interviewed and the forest. We suggest that consensus analysis can be used to validate LEK‐generated data instead of comparing these types of data with information obtained by conventional methods. Read the free Plain Language Summary for this article on the Journal blog.

This study describes a three-year evaluation (2017–2019) of a fertility control protocol using nicarbazin (Ovistop^®) to reduce the abundance of the most conflictive colonies of feral pigeon, Columba livia var. domestica, in Barcelona, Spain, as a long-term strategy based on animal welfare. The treatment was supplied to 34 pigeon colonies by automatic hopper feeders installed in public areas. A superiority study and a population monitoring study were carried out to evaluate differences in the abundance of the colonies, as well as the proportion of juveniles, the possible intake of nicarbazin by non-target species and the movement of individuals among colonies. The results showed statistical differences in the population trends between the test (−22.03%) and control (+12.86%) groups, and a significant steady decreasing trend in the pigeon abundance (−55.26%) was registered until the end of 2019. The proportion of juveniles was significatively lower in the test colonies, and a non-target species (Eurasian collared doves, Streptopelia decaocto) was observed consuming in a residual form. The protocol using nicarbazin is able to both control the abundance of pigeons, with no impact over non-target species, and respond to the public interest about animal welfare by providing an ethical method to manage overabundant and/or conflictive populations.

Context The common pigeon (Columba livia var. domestica) is a synurbic species widely distributed around the world. High local densities of pigeons have negative impacts on animal and public health. Urban pigeon fouling also damages buildings and infrastructures, resulting in increased maintenance costs. Although the reduction of food and shelter would be the most effective control method, it does not apply in most cases where the amount of shelter and food can be unlimited and control very difficult achieve. However, a reduction and control of the population by fertility control using nicarbazin (NCZ, Ovistop®) could be achieved without the need to capture and remove any specimens.Aim and methods The aims of this study were (1) to describe the experience of up to 8years of use of fertility control by NCZ on pigeon numbers in 24 towns and cities in Catalonia (Spain), (2) to assess the potential for non-target species to be affected by NCZ, and (3) to quantify the costs of implementing local population control of urban pigeons via NCZ. Local number of pigeons was estimated via population censuses.Key results From the beginning of the treatment, a significant steady decreasing trend (average of −12% per year) in the pigeon abundance was registered. In very few instances, non-target birds species were observed to feed on NCZ.Conclusions and implications NZC was an effective and selective method of animal welfare to reduce the total number of pigeons in the municipalities included in this study, while not affecting other non-target species. The estimated cost of the annual treatment was €33.6 per pigeon; in 68% of the municipalities, the total annual cost was halved after 3years of treatment. The findings of this study are in agreement with previous experiences controlling pigeon colonies by using NCZ in other countries.

Electronic health records (EHRs) are increasingly used in public health research. However, biases may exist when using EHRs due to whether someone is captured in the data. Assessing the impact of bias in generating disparities identified with EHR data is difficult because information about health care–seeking behaviors is not included in the record. We developed an agent-based model (ABM) to simulate the health care–seeking behavior for community-acquired methicillin-resistant Staphylococcus aureus infection in a subregion of California. The ABM assumed no difference in prevalence across the study area. We modeled the health care–seeking process to see if geographic differences in prevalence would emerge from the ABM when only looking at those who sought treatment, matching empirical data. The ABM reproduced prevalence in observed data for 9 of the 21 geographies. Simulated differences in prevalence across geographies did not reach the magnitude in observed data, and spatial patterns had low to moderate agreement. Our results suggest that geographic disparities in the methicillin-resistant Staphylococcus aureus prevalence previously identified in California EHR data may be due to determinants beyond bias and health care–seeking behaviors. Future studies could adapt this model for other health outcomes by adjusting the health care–seeking behavior parameters and modifying the disease progression process. This article is part of a Special Collection on Cross-National Gerontology.