Canterbury seabirds fighting for survival

The crash-landings have started earlier than usual as Hutton’s shearwater birds/tītī continue to battle the elements and bright lights of Kaikōura.

Hutton’s Shearwater Charitable Trust chairperson Ted Howard said injured birds have already been rescued in the town as new season fledglings leave the nest, only to become disorientated by the town’s street lighting.

Efforts to protect the tītī led to the Kaikōura district obtaining international dark sky sanctuary status last year, with the Kaikōura District Council adopting new lighting rules in the District Plan to reduce the town's bright glare.

‘‘Normally we don’t see crash landings until late March or early April,’’ Howard said.

‘‘This year we seem to be two weeks earlier than usual. The birds came back earlier and began mating, and now the fledglings are ready to leave.’’

He suggested the earlier season could be due to global warming, but marine ecosystems were also variable.

‘‘These birds forage over a large area, so there has probably always been a variability of feed, but I suspect it is getting worse.

‘‘We just don’t have enough data to prove it.’’

If the bird crash lands, it can injure itself or get disorientated and be vulnerable to predators, particularly cats and dogs.

Despite the challenges, the shearwaters at Te Rae o Atiu colony on the Kaikōura Peninsula have fared much better this season.

About 90 adult birds returned to the colony, with 42 eggs laid and 32 hatching.

A record 30 chicks have survived.

In recent years, Howard has fed the chicks ‘‘sardine smoothies’’ as a supplement, due to the adult birds being unable to bring back enough food.

But this season, he has only had to feed four chicks twice, mainly because they ‘‘are essentially solo parent chicks’’.

‘‘We tend to have a surplus of females,’’ he said.

‘‘The birds are like people. Some are in faithful, monogamous relationships, but some are not.

‘‘The distribution in the burrows is interesting, too, as a third of the burrows have only been used by two birds, but some burrows seem to be party central.’’

Te Rae o Atiu colony is a partnership between Tukete Charitable Trust, which owns the land, Te Rūnanga o Kaikōura, the Hutton’s Shearwater Charitable Trust and the Department of Conservation.

It is 20 years since the first translocation of birds from the wild colonies in the Seaward Kaikōura Ranges to the peninsula colony.

‘‘The colony hasn’t developed as fast as we would have liked, Howard said.

‘‘It is slow going, but we are making progress.

‘‘At the moment it is a very tiny colony, but our plan is that over the next 100 years it grows to a colony of at least 10,000 breeding pairs,’’ Howard said.

Ngāti Kurī hope the Kaikōura tītī will one day become a source of mahinga kai for their mokopuna, as it was for their tīpuna.

The wild colonies have not fared as well, with only about a quarter of eggs resulting in fledglings.

Kaikōura's new lighting rules apply to new builds and when lighting needs to be replaced.

Lights should be turned downwards and turned off when not needed, while motion sensors, light shielding and timers can reduce the impact of bright lights.

Outdoor light bulbs should be replaced by 3000 Kelvin or lower.

• If you find an injured or distressed bird it can be taken to The Hutton's Hub next to the Department of Conservation office at 115 Ludstone Rd.
• The Hutton's Shearwater Charitable Trust is looking for volunteers for the FlySafe night patrols. For more information or advice contact 0274424281 or go to the Hutton's Shearwater Charitable Trust Facebook page.

By David Hill, Local Democracy Reporter

■ LDR is local body journalism co-funded by RNZ and NZ On Air.