Description of the Water Pipit project --> click here
Summary:
· Water Pipits (Anthus spinoletta) have been observed roosting in 'Schlammwiss' Nature Reserve since 2000.
· Since 2012 we started ringing these birds in the roost, thus collecting various data and information on these birds.
· In winter, Water Pipits usually spend the day in open wet pastures catching insects and in the evening they gather in small flocks and roost in reedbeds with thick undergrowth vegetation.
· Until this day, we still don't know the origin of our wintering birds. With this project we aim to catch and tag with small GPSs 50 Water Pipits, so that hopefully we will recapture some of them again and get a better picture on the whereabouts of these birds. Our aim is to learn where these birds breed, their migration route and the roosting places they use. To get all this data we need to recapture the birds again in the first three months on 2016.
Groundwork:
In the last two weeks, volunteers and members of the schlammwiss team, have been busy preparing and maintaining the sites (reedbed), where the nets will be set up for this project. Some work has already been done last autumn like cutting trenches in the reedbeds to set up the capture area.
Information:
We are very cautious and have been discussing where to set up the nets to minimize as much as possible the risk that these birds will abandon the roosting site. This is why every step of the work is meticulously taking time and done under supervision of the project coordinator and the ringers. Apart from the roost in Schlammwiss nature reserve, there is also another roost of Water Pipits that we are working on in Mensdorf area. We have already prepared 5 trenches in Mensdorf area to set up nets. With this new site we can work for two consecutive days but use two different sites to minimise disturbance.
GPS:
We’ve got 50 Pinpoint GPS from Biotrack that we received on the 25. February for this waterpipit project. They are working different from the geologs that we used for the reed warbler project.
We can use the GPS for 600s. We tested one GPS in the field to find out
· How long does it need to record one reading?
· Does it make any difference --> outdoor (wetland) or when the bird is hidden in the undergrowth?
· Does movement of the bird make a difference?
After test we can say:
· It needs around 5s to record the coordinates
· No difference when the bird is in an open area or undergrowth
· If it’s moving, it takes more time to record a coordinate (after 70s it switches off)
With this knowledge, we’re calculating that overall we will have between 120-125 recordings on each bird. The aim of this project is to know exactly the origin of these pipits and where they breed.
So the recordings are:
1x recording per week | 4x recording per week | 5x recording per week | 4x recording per week | 1x recording per week |
March - April |
April - mid-May |
mid-May - August |
August - October |
Obctober - ... |
24 o'clock |
24 o'clock |
half past 8 |
24 o'clock | 24 o'clock |
--> see shedule below (photo 1)
We’ll take 5 coordinates per week during the breeding season to find out the coordinates of their breeding grounds. Since we are not sure when they start to breed we programmed the 5 weekly readings from mid May until August. The GPS will take the coordinates at 0830HRS when the birds are very active.
During the migration to their breeding place in April and then back to our wintering grounds around November, the GPS will take 4 coordinates per week. From the test we know that the GPS needs more time to take coordinates when the birds are on the move. So we programmed the GPS to take the coordinates at midnight when the birds are sleeping either during migration or in their roost in winter.
We don’t have enough time and power in the GPS to find out where the pipits spend the day during the winter, questions like: do they feed near or far from the roosting sites? We can take just some coordinates during this time but since the readings in the winter months are programmed to be taken at midnight we will only know whether they come to the same roost every night or if they visit other roosting sites in the region. Maybe we can charge the GPS again next year and see where they are feeding during the day in winter.
First capture:
We (Charel Klein, Dave Lutgen and Raoul Mettenhoven) opened the first nets Friday the 27th February. Since we have been observing the roost for some years now we know which areas they prefer to sleep and we know where water pipits concentrate in the roost. For the first ringing session (we needed to refresh the method of putting GPS on) we decided to open an area where birds don't concentrate. We opened the nets at 5 pm and closed at 7 pm (control at 6). There was football game in the nearby football ground and it was rainy.
We caught:
· 6 waterpipits
o 4 control from 2013 & 2014
o 2 new birds
· 3 Wrens (Troglodytes troglodytes)
· 1 Reed bunting (Emberiza schoeniclus)
We put the GPS the same way as we did on Reed Warblers and use the same harness material.
Before we put the GPS on we check :
· Net number
· Fat & muscle
· Age & sexe (= comparison with photos from the years before and Lucas Jenni book)
· Winglength & length of 3rd primary feather
· Weight & other remarks
Second capture:
With Charel Klein, Max Steinmetz and Philip Birget we opened Saturday the 28th February different nets at Schlammwiss site from the first time. We didn’t catch that much because of a football game in the nearby football ground and over falling balls in the reeds. To the end of the day we caught 3 reed buntings, 1 yellowhammer and 1 waterpipit (which we tagged the day before). We checked if everything is okay with the bird and let it free again.
Back to the sleepingplace:
After each session we close the nets after 7 pm and after the ringing and processing of the pipits, which sometimes takes hours, we always return the water pipits back to the site where they were caught. So they can get out of the roost with the other birds the next morning, this will hopefully decrease the stress and disturbance on the birds after the process of GPS tagging the previous night.
Autor: Charel Klein
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