Wading Birds at Foxton Beach, New Zealand
Foxton Beach estuary mudflats looking west towards the mouth of the river
Foxton Beach lies at the mouth of the Manawatu river estuary (-40.470297, 175.227008) on the west coast of the North Island of New Zealand. The estuary is host to a range of migratory, endemic and vagrant birds. Protected by the Ramsar Convention, it is recognised as a location of huge significance for land, shore and seabirds. The bird sanctuary is a kilometre long beach running east from the mouth of the river as it meets the Tasman Sea. It is one of several major locations in New Zealand that support migratory and local waders. The birds most celebrated here are the visiting birds that spend summer resting and feeding on the food the estuary offers. The largest number of these are the bar-tailed godwit and lesser knot who arrive in early September (southern hemisphere spring) and depart in March (autumn).
Bar-tailed Godwit (non-breeding on left, breeding plumage on right)
The bar-tailed godwit (Limosa lapponica) is now recognised as flying the longest migratory non-stop route from Alaska to Australasia. Unable to feed or rest over water, the estimated 80,000 birds fly the entire 11,000km journey from Alaska to the bottom of the world without stopping. After a 9 or so day flight, they arrive at their feeding grounds, thin and exhausted. These birds spend the summer months in Australia and New Zealand, resting and replacing their feathers and preparing for breeding.
In March they’ll be in great condition, having doubled their body weight for the return journey. This journey is a slightly more sedate affair, as they head to stopping sites along east Asian coasts. Here they feed up again before heading back to Alaska, ready to breed then start the process again. Their chicks will do the long flight to New Zealand at only 12 weeks old.
Whilst in New Zealand, the godwits are monitored by the ornithological society, Birds New Zealand. Through a banding programme, scientists are building more knowledge about the movements of the birds during migration and most interestingly, how many times they make their incredible journey. The information also helps to map the birds and their chosen feeding sites while in New Zealand. Identification through banding can be a complex affair with different colours on a single leg, different positions and flags all having meaning.
There are groups of dedicated people who regularly participate in capturing and banding birds across New Zealand. An additional group of people are also dedicated in recording bands they see in such places as New Zealand. Band details and other information about the sighted bird is submitted to the banding office run by the Department of Conservation. I met such a person recently and her hobby was collecting band details and mapping their journeys across the world. Some birds are also fitted with geo-locators. You can see one on the leg of this lesser knot. It was fitted in 2013 by local scientists to record, via GPS, the migration journey in more detail.
Some incredible information has been obtained from the banding and geo-locators. For instance, some birds migrate on virtually the same day each year and stop at exactly the same sites in Asia year after year. Young birds, however, take their time to establish their routines. The will travel around New Zealand before choosing a regular summer location.
The arrival of the godwits heralds the beginning of spring in New Zealand. Their coming is celebrated throughout the country in diverse ways. Some have ceremonies at local estuaries, some ring bells and even at times planes pulling banners have announced their homecoming. Most people recognise the incredible achievement at even still being alive after the longest known migratory journey.
A particular skill the godwits have is always of interest to me as a photographer. They are able to bend their upper mandible upwards, something known as rhynchokinesis. Mostly they use this ability when digging for food but occasionally you can see them do it while resting on the beach. Much as I hate anthropomorphism, I think they look like they are yawning. It doesn’t help that they usually do it when waking!