Aotearoa|New Zealand coastal Diptera surveys

These datasets provide a record of Diptera found around the coast of Aotearoa|New Zealand.A total of 257 species or morphospecies were identified in total from surveys of both the overall coastal communities and wrack communities.The data also includes information on the ecology, geography, and general conditions present at each collection site. See methods below and ReadMe file (including ReadMe tabs provided within each spreadsheet) for more detailed information.<br>Methods: We surveyed 109 coastal sites distributed around Aotearoa|New Zealand’s three main islands, with 59 sites in the North Island, 47 sites in the South Island, and three sites on Rakiura|Stewart Island. Each site was visited once and sampling trips were made over a three-year period from 2017 – 2019 during the months October – April. Wrack community surveys At sites where wrack was present (n = 79 sites) we carried out standardised collections of the Diptera present on and/or within wrack. For each wrack sample we placed a clear plastic bucket (22cm (L) x 22cm (W) x 23cm (D)) over patches of wrack and held the bucket in place for two minutes to allow time for any flies within the wrack to emerge and move up into the bucket. At each site with wrack we collected ten samples a minimum of 1m apart, with the exception of five sites. At two of these sites we collected 12 samples to ensure we had fully captured the variation in the wrack population present, and at three sites we collected fewer than the ten samples due to lack of wrack for repeat sampling. Overall coastal community surveys We also carried out standardised hand collection surveys at all sites. At each site we spent one hour searching the entire local coastal environment. This area was bounded by the supralittoral zone and current waterline. The searching technique included spending focussed time in all of these different microhabitats to collect as many different species as possible.<br><br>