Enderby Island, a surprising summer holiday home for Ruddy turnstone

Original observation: https://inaturalist.nz/observations/69757982

Enderby Island is a predator-free sanctuary island, part of the Auckland Island archipelago in the New Zealand subantarctic region. Among the abundant native and endemic species encountered, I had a small glimpse at a migratory species which also occurs 14,000 kilometres north, breeding in the arctic and coming south to feed in the off-season. Going to Enderby Island last February was part of a youth scholarship trip with Heritage Expeditions to the Snares and Auckland Islands. Scholarships are still being offered (or will be), and if you are eligible and able, I would HIGHLY recommend the experience!

Derry Castle reef.

Derry Castle reef, a rocky peninsula of Enderby Island, was a subdued landscape of boulders, fur seals and rotting kelp, meaning a closer look at the wildlife would be precarious. I decided to proceed further onto the peninsula for a look, as birds here were different to the ones previously seen on the cushy liverworts and prostrate shrubs of the rest of the island. Honourable mentions on the reef include the Auckland Island Banded Dotterel (Charadrius bicinctus ssp. exilis, observation: https://inaturalist.nz/observations/69758062), and were present in significant numbers, blending in seamlessly to their surroundings. Also, Auckland Islands White-fronted tern (Sterna striata ssp. aucklandorna), Antarctic tern (Sterna vittata ssp. bethunei) and Red-billed gulls (Chroicocephalus novaehollandiae ssp. scopulinus) roosted along the boulders. The seagulls here know a much different life than the chip-begging birds of New Brighton over 1000 kilometres away. I was pointed out to two birds resting on the edge of the reef, which like the dotterels, blended into the surroundings. The bright orange legs were a giveaway. These birds were Ruddy turnstones (Arenaria interpres), and now looking back it was quite extraordinary to see them so far south in the sub-Antarctic summer (dreary at best). From May to August, Ruddy turnstone breed in the arctic tundra, which is quite literally the other side of the world. The NZ Birds Online website states that a bird was tracked as travelling 27,000 kilometres in one migration – a remarkable distance for a bird that can weigh no more than a packet of pineapple lumps (Here’s an observation of a Ruddy turnstone almost 80 degrees north in the Nunavut region of Canada https://inaturalist.nz/observations/29146530. For context, Enderby Island is ‘only’ about 50 degrees South!). This global distribution means that conservation of the species relies on international compliance with general habitat protection for waders. Frigid weather aside, Enderby Island must be a relatively safe location to migrate to for these little birds – perhaps further indicating the significance of this island as a beacon of light (not literal, I did not see the sun there) for the Subantarctic’s unique but vulnerable bird species. Ruddy turnstone also occur on mainland New Zealand in larger numbers.

Posted on 13 December, 2021 08:51 by noahfenwick