Sunday, 18 May 2014

How to catch birds .... not with butterfly nets!


I was showing a person my photos from the Hauturu trip last week and she was fascinated with the photos of the nets we used to catch the birds. I asked her how she thought they were caught and she answered "with something like butterfly nets" after an initial burst of laughter I did reflect that only a few months ago I probably thought the same thing!

This post is dedicated to the catching and processing part of the translocation.

The nets that are used are called 'mist nets' I guess they are called that because of their transperancy. If they are errected correctly and are in the correct lighting then the net becomes almost invisible.

The nets can range in length, the shorter ones we used were 6 metres and the longest 12 metres.
The nets are about 2.5-3 metres wide/tall. They are broken into 4 sections. Each section has a piece that drops below the section underneath it to create what looks like a pocket. Basically the bird flies into the net and falls down into the pocket and is trapped.

This is a diagram showing how the pockets of the nets work.

Chauncy and Kay carefully setting a net out

The net is tied between 2 poles, if you look carefully you can see the far pole.

The nets are spread out to almost the top and bottom of the poles.

When a bird is caught in the net, it is carefully removed.


If the bird is the type required then it is bagged (more info coming up) or if it is the wrong sort of bird it is released. We caught everything from fantails to kakariki to Kereru .... the last left a huge hole in the net :(

So you may be asking how it is that we get the right species that we are after? Well I was wondering this as well! I was really surprised by the simplicity of the answer. An MP3 player!!
Yip, on the MP3 players they have a range of bird calls. We of course were after tieke (saddleback) and popokotea (whitehead) so the calls we were using were of these types of birds.
There were two speakers that attached to the MP3 player. One speaker was placed on eash side of the net. The player would play the calls and the birds would fly down to see what we going on.
When we could see a bird showing interest on one side of the net we would change the speaker to the other side of the net to what the bird was on. The bird would then think that the mysterious bird had moved away and they would follow .... and fly straight into the net.

This is the MP3 player that is used. Notice the box in Chauncy's left hand? That's the switcher box (my highly technical knowledge coming in to play here.) When the bird is on one side of the net, the switch is turned to the opposite side to change the speaker that the birdcall is coming from.

 After the wanted bird is untangled from the net and carefully placed into a black bag, it is carefully carried to the processing station.  

Kevin would be waiting for the birds. He would give them the once over for general health and take a swab and blood sample. On some translocations that blood test results would determine if the birds could be taken but in our case the results would only be used for research.

Then the bird gets handed on to John. His job is to determine the sex of the birds and band them. It was super important to have the right number of male and female birds. Banding the birds means that they are identifiable to anyone that needs to identify them. To me, the banding means that when we see Tieke with no bands in our sanctuary.... the birds have been breeding!!!! YAY  

Washing day on a translocation.... 100 odd bird bags to be washed and dried.... not sure how I ended up doing it!  

The video link below was filmed while I was on Little Barrier. The people that talk on it are the same people I worked with. When you click on the link, a little link should appear up the top of the screen for you to click onto.

Little Barrier birds take flight

I hope this has answered some of your questions about how we caught the birds. It was really interesting working with different people in the catch team. Although they are using the same equipment, the way they work is slightly different. They all think their own way is best which was quite funny! It was great to work with them all and learn their different styles.
This is something that is really important for students to learn- there are many ways to do the same thing that will give the same results. No one has to claim that the way they do it is the only way.

Next blog is on food and avaries :)

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