Citizen science, the enlisting of non-professional scientists to collect data, is a popular approach for involving the public in research. In theory, the benefits of this model are two-fold and complementary: citizen science programs produce useful datasets while also engaging the public in conservation initiatives. However, in practice there may be tradeoffs regarding data quality, cost efficiency, and the effectiveness of public engagement. Here, we quantitatively compared the costs and benefits of collecting biodiversity data by employing paid technicians or recruiting citizen science volunteers. From 2014-2018, we monitored birds and butterflies with a mixture of citizen scientists and paid technicians at 166 urban green spaces across Fort Collins, Colorado. In total, we recruited 88 volunteers and employed five technicians to conduct 2,014 bird and 1,212 butterfly surveys.
Results/Conclusions
We found that citizen scientists reported 40% more detections of human-sensitive birds than technicians, and citizen scientists had a false detection rate of 5% for both human-sensitive and human-adapted species. Overreporting was associated with higher estimates of occupancy and different top covariates in models constructed using citizen-science data. Although the quality of citizen science data was not equivalent to data collected by technicians, we found that the citizen science model was more cost-efficient, producing 50% more surveys and detections per paid work-hour. Lastly, citizen science had clear benefits for enhancing scientific literacy, but did not change attitudes towards nature. Participants experienced a 16% increase in their ability to identify bird species and a 31% increase in their ability to identify butterfly species. Citizen scientists also reported increased interests in engaging in activities related to conservation, such as viewing and learning more about wildlife. We suspect that the lack of attitudinal change may be due to high pre-program levels of nature relatedness and environmental efficacy. Together, our findings support the idea that citizen science can serve as an effective educational tool and a cost-effective model for data collection. However, our findings also highlight potential challenges related to detection rates for human-sensitive species and shifting public attitudes. We recommend that citizen science programs emphasize the importance of reporting certain detections to minimize false positives, and proactively recruit a diverse volunteer base to increase the likelihood of positive ecological and social outcomes for conservation science and practice.