Corey T. Callaghan

Assessing the reliability of avian biodiversity measures of urban greenspaces using eBird citizen science data

Assessing the reliability of avian biodiversity measures of urban greenspaces using eBird citizen science data Corey T. Callaghan , Mitchell B. Lyons , John M. Martin , Richard E. Major 3,4 and Richard T. Kingsford 1 Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, Australia, Royal Botanic Gardens and Domain Trust, Sydney, Australia, Australian Museum Research Institute, Australian Museum, Sydney, Australia, Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, Sydney, Australia

Avian monitoring – comparing structured and unstructured citizen science

Abstract Context. Citizen science is increasingly used to collect biodiversity data to inform conservation management, but its validity within urban greenspaces remains largely unresolved. Aims. To assess the validity of eBird data for generating biodiversity estimates within an urban greenspace. Methods. We compared data from structured avian surveys with eBird data at an urban greenspace in Sydney during 2012–16, using species richness and Shannon diversity indices. We also compared community composition, using non-metric multidimensional scaling (NMDS) and dissimilarities using non-parametric MANOVA. Key results. Structured surveys had a lower overall species richness (80 versus 116) and Shannon diversity (3.64 versus 3.94) than eBird data, but we found no significant differences when using years as replicates. After standardising the richness and diversity indices by time spent surveying in a given year, structured surveys produced significantly higher biodiversity estimates. Further, when grouped into species occupying different broad habitats, there were no significant differences in waterbird or landbird species richness, or in Shannon diversity between data sources. Conclusions. The most likely explanation for the larger magnitudes of the biodiversity indices from the eBird data is the increase in effort manifested in the number of observers, time spent surveying and spatial coverage. This resulted in increased detection of uncommon species, which in turn accounted for a significant difference (R2 = 0.21, P = 0.015) in overall community composition measured by the two methods. Implications. Our results highlight the opportunities provided by eBird data as a useful tool for land managers for monitoring avian communities in urban areas.

Travelling birds generate eco-travellers: The economic potential of vagrant birdwatching

ABSTRACT Avitourism is one of the faster growing subsectors of ecotourism, recognized for its economic value. Much of our current understanding of the economic value of avitourism revolves around bird festivals, migration events, or well-known birdwatching sites. Birdwatchers are a diverse group, some of whom competitively seek vagrant birds (i.e., birds outside their normal geographic range). The economic value from these unpredictable and transient birdwatching events remains poorly known. Using the travel cost method in a readily-quantifiable environment, we estimated that a vagrant Black-backed Oriole in Pennsylvania, United States of America, stimulated travel activity valued at about

History, Current Distribution, and Status of the Egyptian Goose (Alopochen aegyptiaca) In the Contiguous United States

223,000 USD or about

A probable Australian White Ibis Threskiornis moluccus × Straw-necked Ibis T. spinicollis hybrid

3,000 per day over 67 days. Some birdwatchers value rare birds, contributing significant time and financial resources to their viewing. Identifying such significant real economic value from avitourism can help to evaluate competing costs in debate over human land-use scenarios.

Bird interactions with drones, from individuals to large colonies

Abstract We summarize the history, current distribution, and status of Egyptian geese (Alopochen aegyptiaca) in the contiguous United States, using published records and the eBird database of bird observations. The area of occupancy for the Egyptian goose has increased throughout the contiguous United States. The species has three populations that appear to be strongholds throughout the United States: Florida, California, and Texas. The potential ecological and economic consequences of an apparent increase in the United States warrant further research on a number of aspects of Egyptian goose biology.

Egyptian Goose (Alopochen aegyptiaca)

We observed a probable juvenile Australian White Ibis Threskiornis moluccus × Straw-necked Ibis T. spinicollis hybrid on the Lachlan River catchment, New South Wales, in November 2016. Photographs, combined with observations, demonstrate phenotypic characteristics of both these ibis species. The bird had a pattern on the wing similar to the Australian White Ibis but coloration on the body similar to the Straw-necked Ibis. To our knowledge, this is only the second report of a probable hybrid between these two species in the wild, and the first report documented with photographs.