Small sight—Big might: Economic impact of bird tourism shows opportunities for rural communities and biodiversity conservation

The fifth region is the Aleutian / Bering Sea Islands Bird Conservation Region, which we call Islands region. Seabirds dominate this region with some exclusively breeding here includ- ing Red-legged Kittiwake (Rissa brevirostris), Least Auklet (Aethia pusilla), and Whiskered Auklet (Aethia pygmaea) [15]. The Pribilof Islands contain the largest nesting colonies of sea- birds along the continental shelf of Alaska. They are an important destination for remote bird watching with St. Paul Island being the number one Alaska hotspot with over 300 bird species that have been documented (Fig 2) [30]. The International Port of Dutch Harbor in the City of Unalaska is the largest fisheries port in the U.S. by volume caught, emphasizing the importance of commercial fisheries to the region besides small-scale mixed cash-subsistence economies [31]. Since the launch of Alaska ebird in May 2007, about 12,000 ebird app users reported over 358,000 bird observations [12]. Table 1 illustrates that the remote regions of Alaska have higher bird diversity indicated by the number of observable species in the Western and Islands regions while the road-connected Interior region shows higher birding effort from Alaska resi- dents and visitors combined [12]. More detailed ebird data by census area can be viewed in S1 Table. Methods Data The Alaska Department of Commerce, Community, and Economic Development and the Alaska Travel Industry Association partner in the Alaska Visitor Statistics Program (AVSP). The program monitors annual visitor volume using several data sources including border

crossings, and airline travel. In addition, AVSP conducts a visitor survey every five years, col- lecting data on activities, demographics, expenditures, opinions and trip planning through intercept surveys when visitors leave Alaska at airports, ferry terminals, cruise ship docks and other exit points [21]. The data is publicly available [32]. We also used data on bird observations reported in ebird, a citizen science bird observation platform managed by the Cornell Lab of Ornithology. With data from 2007 to 2021 we calcu- lated bird watching effort as an additional metric to the AVSP data [16]. Each record in ebird corresponds to an observed bird species and includes information on the date of the observa- tion and the group size that the reporting bird observer was part of. For future reference, we call these birders who submit bird observations via the ebird app “reporting bird observers.” Birder spending The 2016 AVSP survey included 5,147 intercept in-person interviews and 779 online surveys for a total of 5,926 respondents whose answers were then scaled to the population of visitors Table 1. Observed number of species and ebird submissions by Alaska Bird Conservation Region, 2007–2021. Bird Conservation Region Species Submissions Islands region 367 20,200 Western region 324 55,611 Interior region 281 122,492 Rainforest region 278 142,709 Arctic Plains 278 17,149 Total 556 358,161 Source: Alaska ebird data explorer [12]. https://doi.org/10.1371/journal.pone.0268594.t001 PLOS ONE Economic impact of bird tourism in Alaska

PLOS ONE | https://doi.org/10.1371/journal.pone.0268594 July 6, 2022 6 / 18