Coastal Diptera species and communities and their geographic distribution in Aotearoa|New Zealand

ABSTRACT

The coast provides an important habitat for insects throughout the world. Some insect taxa are entirely dependent on this continuous but narrow strip of habitat between the land and sea, despite the challenging environmental conditions. In Aotearoa|New Zealand (hereafter Aotearoa), the coastal environment is extensive and varies enormously. Aotearoa is also home to a diverse and predominantly endemic Diptera fauna of roughly 5500 species, and a small but significant proportion of these are found along the coast. Here we provide the first extensive survey of Aotearoa’s coastal flies, and describe how the diversity, richness, and abundance of specialised wrack-inhabiting communities vary. Overall, we recorded 257 different species collected from 109 sites from around Aotearoa’s three main islands, with highest abundance, species richness and diversity all found at South Island sites. Our surveys are estimated to have captured over 80% of the species occupying the seashore, and 100% of the wrack specialist community, for which we identified a country-wide baseline community. This study has provided new and interesting insights into the distribution and diversity of flies in Aotearoa. It also highlights the importance of carrying out broad community surveys to capture and improve our understanding of our local fauna.

KEYWORDS:

• Flies
• diversity
• species richness
• abundance
• beach
• wrack
• insect
• populations

Acknowledgements

We would like to thank numerous field assistants for the time they gave to collect samples, including Stephen Wallace, Jessica Le Grice, Robin Le Grice, Ian Le Grice, Leilani Walker, Murray Fea, Neil Birrell, Cass Mark-Chan, Morgane Merien, and Erin Powell. We also wish to thank John Early at The Auckland War Memorial Museum for his help in identifying specimens. R.L.G. was supported by a University of Auckland doctoral scholarship. This research was also supported with funding from The New Zealand Entomological Society and The University of Auckland Centre for Biosecurity and Biodiversity.

Collection of specimens was carried out under Department of Conservation permit numbers 62358-MAR, 59911-RES, and 62362-RES, and Auckland Council permit CS77.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Conceptualisation and methodology, R.L.G., D.W., and G.I.H.; data curation, formal analysis, investigation, and writing of the original draft, R.L.G; writing – review & editing, and supervision, D.W., and G.I.H.

Data availability statement

Data relating this this article is available at https://doi.org/10.6084/m9.figshare.14897466.v1