Out for the count
Denise Irvine takes part in a morepork census in Hamilton.
Gravestones become ghostly shapes in the gently fading light at Hamilton East Cemetery. The pencil-slim conifers turn a deeper green, the bigger loose-limbed trees meld into the dusk, and Brian Challinor sets up a camp stool in front of the grave of Harry and Addie Rowe.
There is a conifer at his back, acting as windbreak, and at 8.30pm on Wednesday, November 7, Challinor starts to listen for moreporks, data sheet at hand to record the details. "It's a bit hard to read in the dark," he says, as he gets out his torch.
Challinor, a retired pharmacist, is counting urban moreporks as part of a five-night Hamilton-wide survey last week, organised by the Waikato branch of the Ornithological Society of New Zealand.
It's an acoustic survey covering 20 city parks, gullies and reserves, and Challinor is among the 65 people who have signed up to spend nippy nights outdoors, waiting for the melancholy two-note "more-pork, more-pork" call from the nocturnal brown owl, whose native name is ruru.
Challinor has been a member of the Ornithological Society for 20 years, and he became interested in birds as a teenager. He does beach patrols for the society at westerly beaches such as Kawhia, Taharoa and Ruapuke, keeping an eye on what birds are going up and down the coast.
He also does a monthly bird count at Forest Lake, Hamilton.
This is his third night listening for moreporks in Hamilton East Cemetery, off Cobham Dr, and so far he hasn't heard a hoot. It is Guy Fawkes week, and only the noise of fireworks punctuates the eerie silence of the cemetery.
Last year, during the first round of the morepork survey, Challinor heard four or five birds at the cemetery. This time, they evade him entirely. He patiently sets up his camp stool over the five nights. There is no action, but it's all in a good cause.
"There were plenty last year," he says. "I think the fireworks made the difference."
There have been decent calls at a number of other sites, though, and organiser Dai Morgan is satisfied with the results.
Morgan, 36, is a member of the Waikato branch of the Ornithological Society, and a research officer (pest fish) at Waikato University's department of biological sciences. He ran the count for the society last year and did it again this year, the main reasons being to collect baseline data for future morepork surveys to be compared with and to introduce and promote ornithology to a wider audience.
Morgan did his master's degree on oyster catchers and his doctorate on magpies. "I like how birds have filled every different niche in the environment."
He also likes moreporks. "I like the calls. There is something about them that is quite special. They [the calls] are easily identifiable. Everyone knows what they sound like." This, he says, makes them relatively easy to count.
Morgan champions urban ecology and believes cities should be considered an important place to conduct this kind of study. "It's where we all live." Such studies shouldn't be confined only to national parks and offshore islands.
The morepork data may also be a way of noting the success of the Hamilton City Council's urban gully restoration programme, and highlighting the value of such spaces as a habitat for native birds and plants.
Morgan says local body and community groups have been doing good work in city gullies for several years. There appear to have been more tui visits as a result, with a resident population probably now present.
But the impact of restoration efforts on most other species, including morepork, is largely unknown, and the survey provides an opportunity to track this.
Morgan notes there has been anxiety over the future of the council's restoration programme, established in 2002 to provide advice, support and plants to landowners wanting to improve urban gullies.
The programme has been praised for its role in fostering a wider appreciation of the city's gully networks, and the subsequent improvement in native biodiversity.
However, earlier this year, the council looked to be about to scuttle the project as part of its widespread cost-cutting moves.
It eventually won a reprieve, although the supply of plants to landowners has been canned, trimming $20,000 from the $65,000 gully budget.
Morgan firmly backs the gully programme. "We have so much gully space [750 hectares] in Hamilton. If we look after this, we will have some great pockets providing flora and fauna."
Last year's morepork count - held in late October - had a good strike rate. The birds were heard at least once at 80 per cent [16/20] of the sites during the five-night survey. At 13 of these sites, they were detected on two nights, and every night at five sites. There were multiple birds at 11 sites, suggesting some may be resident pairs, and breeding.
Results from last week's count appear similar, with 15 of the 20 sites detecting moreporks. The most successful sites were Hammond Bush, Hamilton Lake and Willoughby Park. Pairs were heard at these sites on most nights, and three birds at Hammond and Willoughby on one occasion each.
"This is fairly similar to last year's data," says Morgan, "although generally more birds were detected on more nights last year."
He suspects, as with Brian Challinor's experience at Hamilton East Cemetery, that this could be partly because the latest survey was held during Guy Fawkes week. This had slipped off his radar when he set things up. The unfamiliar noises might have kept some birds quiet.
Morgan says it is not surprising that detection rates for both years were high, because the sites chosen had the vegetation and trees that moreporks typically enjoy. Results, he adds, should not be interpreted as moreporks being widespread across the entire city, because Hamilton has a very low proportion of indigenous vegetation (about 2 per cent, the strongholds being Hammond and Claudelands bush).
The survey was unable to determine gender or whether the multiple birds noted were territorial pairs, or if single birds were transients. Catching and radio-tagging birds would help answer some of these things. But Morgan is confident that the two surveys point to resident populations in about 13 areas.
He is encouraged by the results, hugely grateful to the 65 or more volunteers who counted this year and last.
The use of volunteers to collect scientific data is called "citizen science". It is an effective way of collecting widescale data in a relatively short time, at next to no cost.
Although many on the Hamilton morepork count were probably inexperienced, there were briefing papers available and clear instructions.
Experienced people were mixed through the counting teams, teams were moved around the sites, and Morgan was constantly available on his cellphone as issues arose. Each team was required to text him when they were safely wrapped up for the night.
It's taken a fair amount of work to set up the count. Morgan is nervous on the first night that it will all work, that people will be in the right place at the right time.
"It's not like lab work where you can redo it," he says.
He's counting two separate sites - an hour each at Minogue Park and Horseshoe Lake in Baverstock Rd - and he has not heard a peep at either. At Horseshoe Lake, there are the sounds of fireworks, children's voices, dogs, a peacock [probably from Hamilton Zoo], canada geese and pukeko, but no moreporks.
Morgan is unflappable. "You learn a lot of patience when you do a PhD on birds, sitting for hours on the side of a hill."
His is the voice of experience, but the volunteer counters share his enthusiasm for moreporks. They have turned out in the hope of hearing the plucky calls floating on the night air.
At the briefing on Monday, just ahead of the first night's data collection, there are plenty of morepork stories doing the rounds. Morgan's notion of promoting ornithology to a wider audience is clearly working.
Volunteer Fred Hayward grew up in rural Putaruru, and as a child he saw one low down in a tree branch in the daytime. To his everlasting regret, he shot at it with his slug gun.
"It didn't die, but I've felt guilty ever since. It turned me into a bit of a conservationist. I've planted an awful lot of trees since then."
Lyn Williams is relishing this opportunity too. "I love moreporks. If someone is going to take me to a site where I can hear some, I'm in."
Teresa Simonsen lives in Sherwood Park, off Old Farm Rd in Hamilton East. She regularly hears moreporks calling from a nearby redwood stand and loves the fact that they are part of such an urban setting. She's also heard a shining cuckoo in the tall timbers, and has happily signed up for this count.
Matt Wilson and son Mitchell, 13, are also typical of the morepork team. Last Tuesday night, they hunker down on logs near the bush entrance off Hudson St, Matt's black dog, Shadow, an inky shape beside them in the undergrowth. Shadow's good at sniffing out mice and possums, but tonight there doesn't seem much to interest him.
"Mitchell's the main reason I'm here," says Matt. "He's interested in birds."
Mitchell's apparently known as the bird geek in his class at Berkley Normal Middle School. He likes all birds, but the kaka is his favourite among New Zealand natives.
Mitchell and his dad counted at Donny Park, Chartwell, the previous night. In fact, they didn't hear squeak from a morepork, a disappointing result.
Mitchell thinks Hammond Bush is a better place for them, having big shady trees with hollows where the birds can hang out during the day.
"It's perfect," he says.
It's also a good sign that the previous night's counters at Hammond Bush actually saw two birds, a first for the survey.
Mitchell has seen a morepork. It was at dusk. "It flew across our nana's house at Tamahere." He says they are so stealthy when they fly because of the soft fringes on their wing feathers.
Tonight turns out pretty well. The first call comes at 8.40pm, loud and clear from the south, quite close to Mitchell and Matt's possie.
"Maybe 40 metres away," Matt estimates.
Mitchell and Matt double-check the direction on their compass. The call is answered almost immediately by a fainter cry from the southwest, possibly down near the Waikato River.
"More-pork, more-pork," responds the second bird.
The two birds set up a another sequence a few minutes later, like question and answer, although they are both saying the same thing. One is still quite close, the other more faint.
Then just when you think they are done, there's a decent hoot from a third bird to the east, answering the other two. This sets them off again. There is much to record.
At 9.15pm the strictly timed hour is up for Hammond Bush.
The tally is three moreporks, who have had quite a flurry of hoots. There could even be more out there who chose not to engage. It seems an excellent result.
Mitchell thinks so. "I love this," he says, as he packs up his stuff. "I'll do it again."
The morepork (Ninox novaeseelandiae) is New Zealand's only surviving native owl. Heard in the bush at dusk and throughout the night, they are known for their haunting, melancholic call.
Their Maori name, ruru, means big eyes.
These nocturnal birds hunt at night for large invertebrates, including beetles, weta, moths and spiders.
They catch prey with their sharp talons or beaks.
By day, they roost in tree cavities or in thick vegetation.
They are still relatively common and not classified as threatened.
They have a short tail and are speckled brown with yellow eyes set in a dark facial mask.
Head to tail, they measure about 29cm.
Their average weight is 175g.
They have acute hearing and are sensitive to light.
The female lays up to three eggs, usually two, between September and November.
In Maori tradition, the morepork was seen as a watchful guardian. Source: Department of Conservation