Breeding Bird Survey - A day in the field

12 August 2021 - Published by Francis Buner
It’s a freezing cold Tuesday morning when I exit the house at 5.30 am and there’s a thin layer of moisture on my car window. It’s mid-May, and the weather has been uncharacteristically cold for a couple of weeks. This morning, the Dutch PARTRIDGE team and volunteers are counting breeding birds in the demo area. Outside my apartment, even though I live in the city, the first birds are already singing - a promising start to the day!

This is only the second time that I have joined a breeding bird survey in the field as I am new on the team, having only started work at Brabants Landschap late last year. The first count was two weeks ago, and I have been told that there will be a big difference in what we will encounter today.

 The count starts before or around dawn, so as I turn my car onto the dead-end road that marks one end of the transect, it is still gloomy outside. I am treated to an amazing view of one of the old mills in the area. In the misty dawn, the yellow light of the sunrise makes the landscape glitter and sparkle.



The beautiful dawn is the first of many amazing sights throughout the day


I park my car close to the mill, taking care to make sure any farmers can still pass safely on the rugged asphalt road. It’s important to bear in mind that all farmers, hikers and other kinds of traffic are not hampered by our presence in the field. I take my backpack with lunch and a thermos filled to the brim with coffee and exit the car to wait for Jochem, my colleague and the PARTRIDGE coordinator in Noord-Brabant, the Netherlands.

 In a few minutes, headlights appear and Jochem picks me up. Despite the early hour, we are cheerful, preparing for the days’ monitoring. Jochem hands me the tablet that we will be using for the count and I boot it up as we drive to the starting point. Once there, we are met by Floor, one of our interns, and Henk, a volunteer. After a brief explanation of the type of monitoring we are doing today, we make for the beginning of the transect. To the right of the path we are taking is a five-meter-wide canal, to our left there are hay fields. Lapwings, a pair of black-tailed godwits, skylarks and coots surround us. The first few hundred meters of the transect and the calls we hear, give us an indication of the activity in the rest of the area. There is a lot to hear today. The really trained bird watchers, Jochem and Henk, easily call out what they spot. I dutifully listen, try to memorise the bird and its call, and then enter the location and other data to the tablet.

 It sounds easy, but in the gloomy light of dawn and with uneven, wet footing, it is no walk in the park to do all of this efficiently and correctly! Eventually, after hearing and spotting a great many pheasants, common whitethroats and yellow wagtails in the surrounding field margins and PARTRIDGE hedges, we reach a small raft. It is been specifically built by a participating farmer for the purpose of helping the volunteers cross one of the many wide ditches we have in the Netherlands. It is always an adventure to safely (and dryly!) get across to the other bank. I have found the more often you do it, the easier it gets.



The raft: balancing on it is a tricky business! Floor, our intern, is doing a great job


 The next couple of fields surprise us with a couple of broken eggshells, a small carcass of what looks to be a dead black-headed gull. As the sun rises, the day turns hot and we shrug off our jackets at the midway point when we stop for coffee.

 We sit at the picnic table at the waterside, between the two oldest mills in the area and wonder at the sound of a marsh warbler singing in the reeds nearby. Two PARTRIDGE farmers, who have seen us trekking over the fields, come to check in. One farms on the north side of the canal, the other on the south side. They discuss the presence of the marsh harrier that had a nest here last year, and we share our experiences of the morning thus far.

 When the coffee cups are empty and the tablet has been booted up again, we continue. The transect now runs by the side of a road and takes us past a copse of trees surrounding a small lake. Chiffchaffs and song thrushes, blackbirds and common chaffinches make themselves heard here. The transect is about 8 kilometers, but it takes us the whole morning to complete the route. Listening, looking, checking, double checking, counting and entering the observations onto the tablet is precise work and should be done with care. As the sun rises, we meet more people who are walking their dogs or cycling to work, and sometimes we stop to chat with someone. Many people who live in the area know about the project and some are curious about the state of things or about the results. Of course, we are happy to inform them.

By noon, we reach the end of the transect. We walk the last few hundred meters to where I parked my car this morning, discussing the day’s findings. But before all four of us pile in and call it a day, Jochem freezes.

“Wait, shush, listen!” He hisses. All of us fall silent. After a second or two, Henk nods. “I hear it too!” “A common quail,” Jochem grins proudly, and I enter the last observation of the day to the tablet.

 We have neither spotted nor heard any partridges in the PARTRIDGE demo field that morning. A good sign that they are safely tucked away in the measures, such as beetle banks and insect rich grasslands.  After I drive the others back to the starting point from which we will say goodbye for now,  I can only conclude that today was a good day!



PARTRIDGE breeding bird surveys are based on good teamwork, with me on the left and Henk on the right


In the two graphs below we can see what information the breeding bird counts for our target species during the years have yielded. Immediately obvious is that the number of territories seems to gradually increase in our demo area Oude Doorn, and slightly decrease in the reference area in Genderen. Also in 2021, 96 different species were counted during the breeding bird survey in demo area Oude Doorn, versus 63 different species in reference area Genderen. It is however too soon to draw definitive conclusions from this data, owing to yearly fluctuations. By the end of the project, we plan to thoroughly report on these findings






Written by Fien Oost, PARTRIDGE project manager at Brabants Landschap; edited by Fiona Torrance and Francis Buner, GWCT PARTRIDGE project