Title “Circus gouldi (Adult and Young)”. Juvenile (right) and adult Swamp Harrier (<i>Circus approximans gouldi</i>), subspecies of New Zealand. Originally published in: Walter Lawry Buller: <i>Birds of New Zealand</i>, 1873.
<bdi><a href="https://en.wikipedia.org/wiki/en:John_Gerrard_Keulemans" class="extiw" title="w:en:John Gerrard Keulemans"><span title="Dutch bird artist (1842-1912)">John Gerrard Keulemans</span></a>
</bdi>
1873
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