Whio Journal: Whio Fight Club

The whio, or blue duck, appears on our $10 note and the wild rivers of the back country, and not many places in between. As such, few New Zealanders know whio exist, and most will have never seen or heard one. With just 3,000 left in the wild, a partnership between Genesis and DOC called Whio Forever was created in 2011 to protect and grow the population of this national taonga. For this edition we share some amazing footage of whio fisticuffs and explain why our favourite duck is so feisty.

A month ago, Mike Kirkpatrick from Latitude Guiding got in touch to share a video he took while on a fly-fishing guiding trip in the Kahurangi National Park. They were up the Crow River when they noticed two out of three whio getting agitated with each other, so he started filming to see how it would play out. The whio started chasing each other around but always came back to the pool where it kicked off. The fight lasted about five minutes in total, when one admitted defeat and disappeared downstream.

To show you just how brutal a whio skirmish is, we’ve slowed the footage right down. In the video you can see and hear just how hard they are striking one another with their bony metacarpal wing-spurs – ouch! Later in the footage you’ll see how whio use the river as a defence mechanism to evade threats; the whio that is ultimately vanquished heads up some rapids, submersing itself and popping up in an unexpected spot, to then take advantage of the rapid flow for a quick escape.

So what’s all the fighting about?

Whio are renowned for both their territoriality and loyalty, so the scrapping is about establishing and defending a place to call home, and a mate. When whio pair up, it’s often for life. Similarly, when a whio pair establishes a territory, the only reason they would leave it is on death, or if another whio defeats them.

The length of a whio territory can range from anywhere between 200m – 5km, depending on the number of whio and number of aquatic invertebrates that are supported by the river, their main food source. Whio will patrol their borders daily, usually in the early hours or late in the afternoon (to evade falcons), flying low up and down the river, akin to the low-level patrol flights of fighter jets.

The threat to their territory is usually a single male who is looking for a mate and to establish their own territory. There are more males than females in the wild population because females are more vulnerable to predation by stoats, when they are sitting on their nests, or during a moult, when they lose their feathers and are not as mobile. Furthermore, as the population density increases, territory can be hotly contested by neighbouring pairs with skirmishes going back on forth over an invisible line.

Our blue duck’s territoriality is renowned among those that work with whio. DOC Whio Recovery Lead, Andy Glaser, has witnessed quite a few whio fights in his time, including a pair that fell over a waterfall with their necks entwined, locked in battle, that then popped up in the pool at the bottom – still fighting! Andy recounts a fight that occurred in mid-air, not far above his head:

“I was standing in the riverbed of the Te Waiti Stream in the late evening when I witnessed a whio dog fight that left me gob-smacked.  A pair were undertaking their evening patrol of the river and began chasing a maverick male out of their territory. The defending male was within metres of the intruder, with his female not far behind, growling encouragement. The marauder swerved from side to side only four metres from the valley floor, banking and turning hard to fly back upstream to shake the male, to no avail. They repeated this acrobatic aerial fight for four passes, and on the fifth pass the chasing male caught the tail of the intruder, fixed his wings to land and went into a full stall just two metres above my head.  He held fast to the tail until he was only a metre from the ground and tried to jettison the marauder into the boulders of the riverbed. He bailed out at the last minute to veer off and allow his female to follow through with the chase.  The intruding male narrowly missed the ground skimming the stones and fled for his life. I could not believe what I had just witnessed and let out an involuntary “wow”. Top Gun didn’t have anything on these birds!!”

This defensiveness extends to captive-bred whio pairs. Not only can whio pairs not be housed next to one another because of their territoriality, it’s problematic for them to be located next to other species of waterfowl also. Similarly, in the wild, whio will defend their territory against bird species such as grey ducks/pārera, shags/kawau and paradise ducks/pūtakitaki. As we know, nature can be brutal – victims can also include whio ducklings from neighbouring pairs, who swim over these invisible territory lines.

All this fuss is really about breeding. Whio are excellent parents, raising their ducklings entirely within their territory for up to 80 days until they have fledged. Mike took this footage in August, just before whio in the South Island begin nesting. Whio ducklings should begin to hatch about now, so expect photos of adorable ducklings to start appearing on our Whio Forever Facebook and Instagram pages!

We think Mike sums up the encounter perfectly, when asked to describe it. “It is always great to see our native wildlife in their natural protected state, even if they are beating the crap out of each other!”

Next month we talk to recently retired trapper Ken McNamara from Hokitika, who will share some of his experiences trapping predators to protect whio. For now, mā te wā.