Tuesday, 26 January 2016

Sardine Smoothies Again! Feeding seabirds on Mana Island

Last year I blogged about my volunteer week on Mana Island helping with the Fairy Prion translocation. You'd think the long days, hot sun, and the smell of sardines might have put me off - but when the call came out for volunteers for the second year of this project I couldn't resist the opportunity to put my name forward. I convinced myself that it was a chance to use the skills I'd learned the year before, that the work really hadn't been that hard, the smell of sardines not too bad, and that the sun couldn't surely be as hot again - not in a Wellington January.

Holding one of the new arrivals

Before I knew it I was on Mana Island with other volunteers and the welcoming party of sponsors and Friends of Mana Island members awaiting the arrival of the helicopter and its precious load of chicks.
The helicopter arrives from Takapourewa - Stephen's Island
- volunteers as well as day visitors await the birds

The chicks are carried in 'pet boxes', sealed for the transfer,
but later used as carry boxes for the chicks

You can read about the day to day work in my 2015 blog here.
There are so many questions people have asked me since I wrote that, from the quirky "don't their parents miss them?' to more serious topics, here are the answers to some of these questions.

What do you feed them and how do you feed them?
We feed them a sardine smoothie mix which has various things added to it for their health. Their parents would normally feed them a diet of krill, but the scientists working on this project have found sardines work well.

We "crop feed" them. This means we fill a syringe with smoothie and gently insert a soft tube down their oesophagus into their crop. (See the interactive All About Bird Anatomy to find out more about bird's digestive systems.)
Crop feeding a fairy prion
Do they smell? Did you smell?
Yes, but not as bad as I expected. There are no adults in the artificial burrows so the seabird smell isn't strong in the colony. And you get used to the sardine smell, it's only visitors stepping into our feeding caravan who comment on it!
A volunteer doing dishes - hygiene is a priority

How old are the chicks when they arrive?
The chicks are over a month old, possibly even 6 weeks old. The aim was to have them fledge within two weeks of their arrival, so they are selected based on wing length and weight  by the team on Takapourewa - Stephen's Island. When they arrive some are still quite fluffy but they lose their down quickly.
This chick is losing its down, leaving just a fluffy hair-do

Don't their parents on Takapourewa - Stephen's Island miss them?
We assume that because the chicks are so close to fledging that when the parent birds return to the burrow and find it empty, they will think their chick has successfully fledged.

Do the birds peck you?
Fairy prions are very little, they weigh about 120g as adults, so even if they peck it doesn't really hurt. You can see in the photo above that their beaks aren't much longer than a finger width. We had one bird this year, that I named 'pecky' as it was pretty feisty and was always trying to grab our fingers in its beak and would chomp down on the tube if you weren't careful.

How do you tell the birds apart?
They all have numbered bands around one of their legs. The burrows are also numbered. Each chick is allocated to a burrow and is only taken out for its daily feed or to have its wings measured. We had to be very careful with our record keeping.
Checking band numbers in the shade
by the feeding caravan
Measuring wing length at the numbered burrows

Are fairy prions endangered?
No, according to NZ Birds Online there could be 4 million pairs of them on New Zealand offshore islands. NZ Birds Online.

So why bother to translocate them? Aren't translocations just for rare species?
Seabirds do an amazing job in creating an ecosystem. They dig and burrow, they use vegetation for nest material, they poo, they drop feathers, they die. These actions change the land and bring nutrients from the sea to the land. This improves the ecosystem for plants, for insects, for lizards and for other birds. Bringing more of them back to Mana will help restore the ecosystem to what it was before humans arrived.
An artificial burrow showing an accumulation of nest material, feathers
and guano - a gecko dashing away in the foreground

The artificial burrow area looks a bit bare but returning adult birds will work
wonders on the ecosystem

New Zealand is sometimes called the seabird capital of the world because so many different species live here. When humans arrived they brought pests such as rats and they the modified the land for farming. This has made it harder for seabirds to survive on the main islands or islands like Mana that have been farmed in the past.

Fairy prions will return to where they fledged (left their burrows and flew out to sea for the first time) when they are adults. So a good number of these chicks are expected to return as adults.

Information about seabirds for children in
Under the Ocean: explore and discover New Zealand's sealife

What do you mean by 'translocate', why don't you just say 'transfer' or 'move'?
Oops was I guilty of talking jargon?  With some relief I found the answer on the Department of Conservation website. "Translocation" refers to the whole process which may involve several "transfers" (this was the second of two transfers). The term also covers planning and monitoring.


Footnote: 100 birds arrive on 17 January and were cared for by 7 volunteers led by scientist Helen Gummer. The first fledged on the night of the 19th and by 24 January when I left the island, there were 62 birds left.  Volunteer groups stay a week at a time, overlapping the previous group by a few days.

Acknowledgements: This amazing project needed many people and organisations to work together for a successful translocation. A volunteer is but a small spoke in the wheel. I am grateful for the opportunity to be part of this and want to acknowledge the many others who have played much more important roles than mine. The sponsors OMV; Friends of Mana Island; scientists Helen Gummer and Graeme Taylor, Colin Miskelly; Jeff Hall, the resident DOC ranger; Ngāti Toa; Ngāti Koata; the Department of Conservation; and the other volunteers.

Related Links:
My volunteer experience in 2015: http://explorediscovernature.blogspot.co.nz/2015/01/feeding-fairy-prions-volunteers-week-on.html

Blogs by scientist Colin Miskelly on the 2015 collection of fairy prions and transfer: http://blog.tepapa.govt.nz/2015/01/27/a-box-of-fluffy-birds-moving-fairy-prions-from-takapourewa-stephens-island-to-mana-island/

Friends of Mana Island: http://manaisland.org.nz

Fairy Prions: http://nzbirdsonline.org.nz/species/fairy-prion

Translocations: http://www.doc.govt.nz/get-involved/run-a-project/translocation/

Bird anatomy: https://academy.allaboutbirds.org/all-about-bird-anatomy/