Karearea – a season of the falcon
Karearea – a season of the falcon
Karearea (New Zealand Falcon – Falco novaeseelandiae) are a beautiful, rare, and threatened species of falcon. They are the only living raptors endemic to New Zealand.
From July through to November 2011, I had the privilege of observing a pair of Karearea at ZEALANDIA bring a healthy male chick into the world and raise it to independence – a season of the falcon.
The karearea were fully wild birds, free to come and go to/from the sanctuary as they wished. But by being patient and still, they tolerated me to a remarkable degree. Indeed, they regularly flew to me, landing on perches within three metres of me to preen or devour prey; watchful of me, but unafraid. I was able to observe their progress through aerial courtship ballets, mating, nest finding, laying, incubating, hatching, brooding and feeding, to finally fledging a chick.
Ironically, after all that devotion, a falcon season ends when the parents drive their youngster away to seek a territory of its own.
Birds on the menu
It’s a fact . . . New Zealand falcons feed mostly on other birds, which meant not everyone was happy to see a pair of such efficient predators make their home in the ZEALANDIA valley at Karori. The sanctuary is also home to other threatened native species such as tieke (saddleback), hihi (stitchbird) and kakariki (red-crowned parakeet) . . . all natural prey for karearea. But predators play an important role in the ecosystem, weeding out weakness and maintaining balance. Like most predators, falcons benefit a population by removing the sick, injured and deformed. They take their prey on the wing in swift dives, off the ground, and even by flying through branches and pouncing.
Ron Goudswaard from ZEALANDIA describes their hunting technique as follows:
“Their usual strategy is to perch on a low branch of a tall tree high on a hillside with a clear view of the surrounding countryside and to watch the movement of the birds below, looking out for those that are young and inexperienced or not keeping a sharp watch.
“The low branch means the falcon is in the shade cast by the tree and is very hard to spot. The high position means that the falcon can simply drop off the perch and quickly gain speed in a power dive. And if the prey is on or near the ground, the prey can’t dive down to get away, it has to go up, towards the falcon.
“Most of our New Zealand birds have evolved with falcons and know where to watch and how to react. It is the introduced European birds that falcons are catching the most of in the sanctuary valley. In Europe there are several different birds of prey, each with their own style of hunting, but here the introduced birds have to contend with a falcon which combines the hunting strategies of all of them. It would seem the European birds have no instinctive awareness for that.”
My own observations of the pair at ZEALANDIA concur with Ron’s statement. While some native birds were taken, including kakariki, toutouwai and popokatea, the vast majority of prey I saw brought back to the nest were starlings, along with a mixture of blackbirds, finches and thrushes – all introduced species.
Sex in the air!
The photo at right hit the headlines. It was blurry, it was grainy, it was blown up out of a tiny part of a distant shot . . . but it had sex appeal!
I had spotted the karearea on 3 July 2011. They were dancing together high above the sanctuary valley, swapping food mid-flight, looping the loop, performing mock attack dives on each other, and engaging in spiraling paired dives as they renewed their bonds. Falcons, like many birds of prey, are monogamous and pair for life, but renew their “vows” with seasonal courtship.
Their aerial ballet was too distant to photograph. But I followed them into their tall-pine valley and, on 16 July, got this photo of them mating. It appeared on the Stuff website with an ‘explicit’ warning and was an instant hit. Thousands of views and many comments.
A new generation was on its way, and a new love affair was born – not the falcons with each other, but mine with them. We were to be constant companions for the next four months.
The pair selected a small valley overlooking Tui Terrace ZEALANDIA as their home. Surrounded by old pines, which offered a multitude of perches for devouring food and watching – karearea spend a great deal of time watching – the valley also included an area of pine slash and sparsely spaced tall, spindly pines among which to hawk for prey, or from which to spy across the valley. The pine slash mixed with regrowing native forest was a preferred nesting site. They had used the same area for a second, but unproductive, nesting effort the season prior, the first recorded incident of karearea attempting to double nest in one season. Much time was spent selecting the nest site (by both sexes) between frequent bouts of mating, and regular offers of ‘gifts’ by him to her, of prey.
Eventually, a site under a large felled log was chosen. She visited it many times, clearing, scratching and generally satisfying herself it was the right place. He visited less often, but seemed to concur with her selection. The log was more than a metre thick and the space underneath it was a natural bowl lined with pine needles and well protected from the elements.
The nest itself was frustratingly out of sight of my lens, but a flat-topped mound beside the nest site proved to be the falcons’ favoured landing space before slipping under the log. This made for good coming and going photos. Later it was the chick’s favourite sunning spot. A branch above the landing spot, high enough to observe the whole nesting area, was the male’s favoured watching and preening place.
An egg is laid – a chick is hatched – a young bird flies
By late July the female had settled into a pattern of spending long hours in the nest under the log. The male brought her food, and took long turns under the log also. It was obvious an egg had been laid and incubation was under way.
Late August and the food bringing by the male stepped up and he was most anxious to take time on the nest. But, whereas earlier she had been happy for him to take his turn, now she denied him. She would fly out to take food off him and then go straight back to the scrape. In spite of intense mewling and begging from him, his efforts to take a turn were denied. A chick was in the nest!
On 7 September the chick was judged to be about 10 days old, big enough to be banded (just!). Weight, bill and leg measurements suggested it was a male. The other egg failed to hatch. When the chick was returned to the scrape after banding I was allowed to grab one, very quick, photo. It was amazing how quickly the parents settled down once their youngster was back in place and we moved away.
For a week or two only the female fed and brooded the youngster. But it’s demands soon outstripped the hunting abilities of the male alone, and she began to join him in the cycle of hunting and feeding, though still taking the lion’s share of actual in-nest time with the growing chick.
She also preferred to feed the chick and would frequently demand the food off the male. He clearly wanted to feed the chick himself, but mostly she got her way and took the food off him to take to the youngster. Soon the growing chick was venturing out from under the log to sit, and eat, in the sun, its down rapidly being replaced by juvenile feathers. The chick’s use of his favourite mound allowed us to observe the its rapid growth.
In only four weeks the tiny fluff ball of white down, small enough to cup in the hollow of one hand (with room to spare!) turned into a sleek, fully feathered raptor flying swiftly through the trees of its birth valley, making mock dive attacks on its parents and ready to learn the serious art of hunting.
Karearea – a short biography
Karearea, the New Zealand Falcon, are also known as Bush Hawk and Sparrow Hawk. They are often mistaken for our largest raptor, the kahu (Australasian harrier – Circus approximans) but closer observation shows they are distinctly different in size, colouration, shape and styles of flight. The falcon is about half the size of a harrier and its wings have a sharp, angular profile compared with the broad sweep of a harrier’s wings. Falcons fly fast with rapid wingbeats, harriers fly slowly with languid wing beats and glide a lot, circling and almost hovering to look for prey. Falcons perch to look for prey then dive on it at speed. Harriers frequently take carrion (often seen feeding on road kill in rural areas), falcons rarely do. The male falcon (43cm, 300g) is two-thirds the size of the female (47cm 500g).
Karearea are mainly found in heavy bush and the high country in the South Island and lower North Island. They are rarely seen north of a line through the centre of the North Island. A small population breeds on the Auckland Islands. Heather and Robertson (The Field Guide to the Birds of New Zealand – Penguin) describe regional variation in the New Zealand falcon: “. . . three forms that differ in size colour and habitats: the ‘Bush Falcon’ of forests of the North Island and Northwestern South Island; the ‘Eastern Falcon’ of the open country of the eastern South Island; and the ‘Southern Falcon’ of coastal Fiordland, Stewart Island and the Auckland Islands”. Bush falcons (as featured in this blog) are generally the smaller of these three types, their size an advantage when flying at high speed through the trees to flush their prey and capture it mid-air.
Cats ‘n’ rats, people ‘n’ power lines
Karearea are a nationally threatened species because of predation by introduced pests (cats, rats, stoats, dogs etc) and illegal persecution by humans. Far too many falcon are shot by rural dwellers in spite of being fully protected since 1970, sometimes because of mistaken identity (farmers sometimes shoot harriers in spring in the belief that they attack lambs), or because of attacks on domestic fowl (hens, doves, racing pigeons). But sometimes they are shot simply because our rural/farming European history has conditioned us to see raptors as pests, a threat to domestic livestock and fowl. People simply don’t realise how special and endangered karearea are. Neither do they appreciate the crucial role predators play in a healthy ecosystem. So, while “cuddly” birds like kiwi are revered, raptors are seen as “killers”. This anti-raptor attitude is sometimes observed even among otherwise passionate “greenies”. Some people thought the ZEALANDIA karearea should be “put down” or at least “moved on” (somehow) because of their threat to the other rare natives in the valley, not realising that the interrelationship between hunters and prey helps keep an ecosystem, and prey populations themselves, healthy and balanced.
Many other karearea die on overhead power pylons as they are just large enough to make contact across two wires, and are drawn to the pylons as high vantage spots.
Education is seen as the answer to human attitudes toward karearea (in Maori mythology raptors are revered as messengers from the gods) and conservationists are lobbying power companies to increase the spacing between power lines, a practice common in other countries.
Even if all these problems are solved, karearea are unlikely to ever be common, as a single pair requires a large territory, meaning the birds are widely dispersed and there are few per region compared to other species of birds in the same space. For instance, one karearea pair’s territory is large enough for some 400 little spotted kiwi and hundreds more of each of the other smaller bird species.
Another reason karearea are killed is because they will readily attack people, especially in breeding season. There have been several reports of people justifying shooting these rare and precious birds because they, or their family members, have been dived upon, which can be a frightening, experience. Karearea generally ignore humans, and are quite unafraid of us (perhaps indifferent is a better word), but when eggs or chicks need protection, they defend their territory fiercely.
They dive on any intruders, accompanying their attacks with loud, high-pitched and rapid, “kek kek kek” alarm calls. Interestingly, attacks on large targets such as people usually involve the birds raking the back of their “knuckles” across the head of the intruder, not their sharp talons. It has been suggested they do this in to avoid damage from hitting a heavy object at speed, or simply to avoid imbedding their talons and getting stuck. Nevertheless, karearea attacks can readily draw blood from an unprotected scalp! And the closer an intruder gets to a nest, the more likely the actual talons will be brought into play. The same “kek kek kek” call is used as a hunting call and territorial marker, but to each other karearea often “mew” in a soft, high-pitched whine that has a querying note to it.
The karearea at ZEALANDIA had a keen perception of what was “their” space and allowed observers very close if we were quiet and moved slowly. But a dive-bombing attack was instantly perpetrated on those who, usually unwittingly, stepped across the invisible line that the falcons regarded as marking the edge of their “strictly no go” territory. It was easy to work out where that line was and stay behind it.
I also noticed they were more inclined to attack groups than people on their own, perhaps because it’s easy to keep an eye on one potential threat, whereas a group represents multiple threats and it’s hard to watch them all, so it’s easier to try to drive the intruders away.
They saved their most savage attacks, however, for other birds. Potential predators such as karoro (black backed gulls), kahu (harriers) and even kaka were mobbed ceaselessly, feathers flying until the unwanted birds were driven off.
Karearea nest in a scrape in grassy soil or humus in various locations: under a rock on a steep slope or on a rock ledge, among epiphytic plants on a tree branch, or under a log or branch on the ground. In such sites chicks and eggs are vulnerable to introduced predators, so this fierce defense is understandable.
Nearly every reference to the speed of a falcon attack quotes the peregrine falcon, which is a record holding speedster with recorded power dives of more than 200kph. While there seems to be no record of any attempt to measure the fastest speed that karearea can attain during level or diving/stooping hunting flight, they are not thought to be as fast as peregrine.
Richard Seaton, Research Development Manager at Wingspan Birds of Prey Trust in Rotorua says: “Peregrines’ modus operandi is to stoop at prey and as such they have long pointed wings, a relatively short tail and stiff feathers, all of which enable them to hunt very efficiently by stooping. Karearea also stoop at prey but it is not their main method of hunting. Being a forest falcon they more usually hunt more like an accipiter – employing surprise attacks from perches and hunting flight using cover. Not relying on all out speed, karearea are far more manoeuvrable than peregrine and have short, relatively deep rounded wings, a long tail and have not developed the stiff feathers found in birds that stoop for a living.
“All that said it is my belief that the Karearea is very likely to be New Zealand’s fastest flying bird as it is easily able to keep up with even the fastest of prey species available in New Zealand in level flight (even without stooping). Prey that gets away usually does so by out manoeuvring falcons into cover rather than outpacing a bird. Being a falconer for many years Noel Hyde at Wingspan has had more experience than most in observing falcon hunting behaviour and it is also his view that in straight line level ‘hunting’ flight – they are New Zealand’s fastest bird.”
I have also seen other references suggesting a karearea stoop can exceed 100kph. That would make it faster than that other great diving attacker in New Zealand, the gannet, which has been recorded hitting the water at just on 100kph.
Breaking the rules
It’s uncommon for any bird of prey to produce chicks from a second nest in the same season and, until 2010/11, there was no record of karearea attempting to do so. But the ZEALANDIA pair have confounded the experts by going ahead and doing it anyway.
The first time the pair was observed to be attempting pair a second nest in one season was in 2010, but that nest failed. At the time it was believed to be the first record of falcons in New Zealand even attempting to breed twice in one season.
Then, in December 2011, after fledging the youngster pictured in this blog, the adults were seen mating again. It looked like they were going to try a second breeding. A few weeks later staff at ZEALANDIA reported behaviour by the adults suggesting another generation was on its way, and a nest site was later confirmed.
This was all confirmed in February 2012 when sightings of at least one karearea fledgling were reported. I saw the youngster myself but my photo was so distant it pixilates when enlarged and cannot be used here.
Richard Seaton of Wingspan says of the successful second breeding in one season: “It’s never been documented before and should go into the scientific literature.”
So why ZEALANDIA? Seaton has some thoughts:
“It indicates ideal conditions for breeding – an abundant and readily available food source combined with suitable nest sites. It may suggest that introduced mammals outside the sanctuary not only impact nest success through direct predation pressure and reduction in prey abundance– but may also reduce overall breeding success by increasing stress. That is, removing predators may reduce the time spent in nest defence – leaving more energy for breeding activity.”
Seaton suggests an alternative rational might be linked to density dependence. There are very few wild falcons in the Wellington area and the lack of other pairs in the sanctuary combined with high prey abundance may promote increased breeding.
“Without detailed study it is difficult to determine the reasons for the behaviour but it is very exciting that this threatened species is doing so well there!
“The increased breeding success in The Sanctuary illustrates the potential of this species to thrive all over New Zealand. There is much we can all do to support this threatened species even without a predator fence. This rare and charismatic species is threatened by illegal shooting, introduced predators and a general reduction in the numbers of small birds on which it preys. Halting persecution, reducing mammalian pests and supporting land-use practices that provide conditions suitable for falcons to breed would mean that every day New Zealanders could experience this spectacular bird not just in the backcountry of New Zealand but in our day-to-day lives. Something that we at Wingspan believe would enhance the lives of all New Zealanders.”
My falcon photos on Flickr