Wednesday, 24 October 2012

Rarity boom!!

Yes, finally! Autumn has erupted and the birds are on the loose. Lucky me for spending so many hours on islands (Texel and Vlieland). I was so rather busy that I forgot to work on older recordings, let's say from couple of weeks ago..
At the second weekend from Deceptiontours (DT2), the young lads (including me) were cycling just past Leo Heemskerk (a little bit older lad ;) ) and only 50 meters farther, I discovered a Richard's pipit (Anthus richardi) on the ground. That's the way to make the difference! ;)
Some record-recording:



But last weekend it was booming. A few days before, a total of 4!! Olive-Backed Pipits were present on Vlieland near the water treatment plant. So I helped Jelmer with another recording, although it was not that good (lots of people..) so I just ran away.. Find my own bird, I said. Then in the afternoon, a phonecall.. Sjoerd had found a candidate Siberian Chiffchaff (Phylloscopus collybita tristis). As I have never heard the call of a Siberian Chiffchaff in real life, I was very curious! I listened to his recording (on his phone!) and I must say: I was convinced it was a 'tristis'. After searching some time, we found the bird, sometimes calling and sometimes showing, but it was very active. I recorded some calls.. But then.. I bumped my head in very interesting matter. 'abietinus' vs 'tristis', were to draw the border..



And the sonogram:











A 'sweeo' call. Known from both 'collybita' and 'abietinus' and might occur in 'tristis' however, no guarantees. On XC this type of call has been heard (and recorded) on birds that have the plumage of 'tristis' (for what we know!) in Oman and the type of call seems to become rarer towards India. This could imply a transition zone from 'abietinus' to 'tristis', or could imply that this sound is not (sub-)species specific! Another problem: Sjoerd's phone crashed, and he had the best recording, so hopefully the recording is saved on the SD.
Fortunately, in about a week I myself will visit Oman for fieldwork (watching Crab Plovers for 7 weeks) so I will be in the opportunity to sometimes record a Chiffchaff (and photograph it for the almost full documentation). (And yes, I already made a list of species where is only one or even no recording present in XC ;) ) Can, and hopefully will, do the same in Kazachstan next spring, will come back to that later.

So, bad luck.. Saturday was even worse! In short: was birdwatching with Mark, worked our asses of, checked EVERYTHING, found NOTHING, and then Radde's Warbler.. New species.. 4 hours of frustrating 'I see him! AAAAND it's gone' was taking me to the limit when I finally saw it. Criticaster me was discussing about the identification when Marijn called, I ignored his call.. 5 minutes later I gave Marijn a call and he was talking about 'something really strange, no idea what it was, some pipit with an metallic call in the forest (100 meter away!!!)'. We also went in to the forest and saw a crowd yelling and screaming and go mad whilst screaming 'It's a dendroica, it's a Myrtle Warbler'. What happened? The bird just was heard calling, 30 seconds ago.... F@#$ karma.. Gave a listen to the recording, thinking about Pechora and decided to play Pechora on my phone.. Surprised looks on the surrounding people asking: what is that? What are you playing? That's the sound!
Well yeah.. The sound really looks like Pechora Pipit (Anthus gustavi). However, only a few recordings are available and the sound does not match exactly. If it indeed was a pipit (bird was not seen through binoculars and only very short!), then it must have been a Pechora. The next day, the bird was heard 3 times more, but I didn't manage to hear it. However, to my opinion, there is not enough evidence.. But we will see!

In the evening I decided to stay on Vlieland to give the bird another chance. In the last daylight we were checking the fields near the village when we heard a 'raw rasping' wagtail. Alwin was the first one to spot it and yelled Citrine Wagtail. The others also saw the bird and the ID changed to Eastern Yellow Wagtail (Motacilla tschutschensis). It was windy, but fortunately, I made a recording in the hassle of tacking pics, clashing the ID, call others et cetera.. Only one call, but still! Damn what a sound. A rasping 'srieeuw' which is little bit reminding of Richard's Pipit. As we were photographing, a car approached us from behind, we gave him space to pass us, he got angry and horned loudly and flushed the birds to never see them again...
The recording (well.. ehm yeah..)


And the sonogram:














As you can see it is a bad recording. However, you do see the rasp in the call, the saw-tooth ('zaagtand' in Dutch, dunno if I can say it in English). It appears that the call is broken due to quality, yes it partly is, but it's due to the softer and harder quality of that part of the call, which is given its rasping sound (more or less). Untill now, this type of call has not been documented for Yellow Wagtails (Motacilla flava incl (sub)species). And the occurence always in late autumn and with very grey-white birds, this indicates an eastern origin. Here some pictures of the bird on waarneming.nl.
Well, another interesting matter: how do, for example, Yellow Wagtails from the subspecies 'beema' call? They are geographically close to M. tschutschensis.. Well, this spring I will go to Kazahkstan and as with the Siberian Chiffchaff, I hope to help with clinching the ID problems.

As if it couldn't get any stranger (note that the Eastern Yellow Wagtail was almost at the same spot as the Raddes and the Pechora), in the morning (in dense fog) we were waiting more or less at the Pechora spot, when all of a sudden (well, sort of) we were listening to an intriguing sound in the fog, which independently from each other drew our attention... Never seen the bird, nobody knows what it is.. A crate of beer for the one who knows (tip: do not only listen to the sound, also LOOK at it!). Note, it is the 'chep'-call


And the sonogram:




















The feeling about the weekend changed when I got home and saw (again with help of Jelmer) that I recorded an Olive-Backed Pipit (Anthus hodgsoni) that flew over the village :)


Here some small extras. First a atmosphere sound on monday morning in the dense fog and immense migration!


And a comparison between the calls of Blackbird (Turdus merula) and Redwing (Turdus iliacus)

Tuesday, 16 October 2012

It has been a while

It really has been a while since I wrote a blogpost. I've been rather busy with my study and of course: it is top-birding time. Unfortunately the wind plays part in both the birds as the recordings.
The end of August I was at the Lauwersmeer for a week of birding. Only one morning it was good weather for recording, and so I did! The first birds I recorded were begging Water Rails (Rallus aquaticus), somewhat different from begging Eurasian Coots, and as far as I know, the only recording available on the internet. It differs in the number of bands and that it is more horizontal.


A couple of meters further, a Grasshopper Warbler (Locustella naevia) was present and calling quite anxiously. Didn't hear this one before (for earlier recordings of Grasshopper Warbler, see here)! It might have been a little afraid, but the bird showed up at only a half a meter (deep in the vegetation)


Then a couple of weeks with southwesterlies and less birding, but on 8 September Toy and I spent a visit to a Zitting Cisticola (Cisticola juncidis) which was present at Hendrik-Ido Ambacht. It was surprisingly rare in the last few years, whereas it was more abundant the few years before that. Already when entering the area, we heard the loud song!
Now it becomes more interesting ;) Every autumn since 2007 I spent 1-3 weekends on the island of Vlieland (Deceptiontours) to watch for rare birds and spent nice evenings in the local pub. As this is an island, Eurasian Nuthatch (Sitta europaea) is rare! This weekend some (2-3) individuals arrived on the island (new species for Vlieland) and the day after I succeeded in finding one and record it. Recordshot:
One of the few nice mornings this autumn (23 september), Toy, Alwin and I were in the search of Richard's Pipit (Alwin needed it for his Big Year), so we walked over the whole Hondsbossche Zeewering (for foreign people: a 5.5 km long dyke preventing Noord-Holland from flooding). A lot of migration was going on and I recorded some Yellow Wagtails (Motacilla flava), one of the last times this year.. Unfortunately
Then a Rock Pipit (Anthus petrosus) flew by and luckily I recorded it! I say luckily, as I'm curious in the differences in call between Rock and Water Pipit (Anthus spinoletta). So hereby also a request: if you see one of these two species, try to record their flight call! One precondition: you have to identify the species by plumage! Not occurence! Please upload it to waarneming.nl, observado.org or xeno-canto.org. Thanks a lot :D

Later that morning we twitched a Red-necked Pharalope (Pharalopus lobates) in the fields near the Belkmerweg. The bird was foraging solely. Toy and Alwin couldn't resist getting closer to the bird for pictures. I couldn't resist trying to tape the bird, I did once and the bird responded softly. I had my mic ready and at a given moment the bird flew (no reason, for sure!) towards me, calling. The first recording of Red-necked Pharalope for the Netherlands. Nice sound! The bird flew to another field where it was heard calling every now and then.


Then a few weeks with too hard wind and busy with moving, study and watching birds. Untill yesterday 15 October. A 'piepje' warned me that there was a Olive-backed Pipit (Anthus hodgsoni) on the island of Texel. I recently moved to Texel, so this was a home match! I saw the message quite late, but just in time to get picked up by Alwin. Together we drove to the spot and spotted about 30 sad faces, all deciding to go home. We stayed with about 5 people and after two hours of searching, Jurrien found the bird! I didn't manage to see the bird, but heard it clearly, and recorded it less clearly! Later we found the bird sitting and the views were oke, at least for me. As I'm interested in Rock vs Water, Jelmer Poelstra is interested in Olive-backed vs Tree Pipit, so this one could be added to his collection ;).

Oh yeah, by the way: it was a LIFER!!



Saturday, 18 August 2012

Spanish Pyrenees part 2: Sierra de Guara

The second week in the Spanish Pyrenees we were departed in a small village called Nocito. It is at the northern side of the Sierra de Guarra and still called part of the Pyrenees. This part has a complete different geology and is much lower than the High Pyrenees. Thus, more species, and especially more numbers both for birds as butterflies. The first few days I needed to rest and adapt to the much higher temperatures and spent some time in butterflies. We had found a kind of oase where butterflies came for their much needed water and nutrients (peeing on the road!!!) and we could chill underneath an overhanging rock and in the slow streaming creek, what a life!
One of our groupmembers got stung by an insect (probably mosquito..) and his feet bulged in such a way he couldn't walk anymore. So we transported him to the hospital and the doctors must have thought it was an unknown highly contagious disease, so they kept him in the hospital... The next morning, Jorrit and I were at the hospital to pick him up, but they still didn't let him go. So we decided to go for birdwatchin just out of Huesca. The first kinda road (more a dirt track..) we parked the car and went for a walk. We heard a sound that both made us laugh and say: a flying horse?? Then it dropped.. There were some Black Kites (Milvus migrans migrans) flying and calling. One individual was sitting in a tree and sometimes gave a call. At these moments, even when it was already 30 degrees, I get the goosebumps!


In the same area (agricultural), I finally managed to make a decent recording of European Bee-eaters (Merops apiaster). It are very difficult birds to record, as the are shy, flying high and softly!


In the meantime, we could pick up Sjoerd in the hospital, supplied ourselves with loads of water, food (sweet stuff and loads of beer) and other stuff and went for Roldán. A place where we only had heard of, but it was supposed to be awesome with vultures. So we went, in the heat of the day. We drove towards Roldán and in the distance we saw two huge cliffs where vultures were circling.. Could it be there? In fact, it WAS there! We parked the car (nobody else!) and walked around the cliff (it really is a 400 meter steep cliff). We saw some Sub-alpine Warblers (Sylvia cantillans cantillans) and saw two Western Orphean Warblers (Sylvia hortensis), not quite a species I suspected here but a tick for me! One individual was kind enough to give a call while recording. I'm sorry to dissappoint you, but this one comes later in a Sylvia-special (muahahaha, sounds exciting heh?). This all was guided by the vultures demonstrating Doppler-effect by their wings. So close, amazing! Well, it's one of those breath taking moments were you will think of when you're old..
Roldán - copyright Jorrit Vlot






























Around our campsite there were several Iberian Green Woodpeckers (Picus (viridis) sharpei). They
especially called in the early morning (with hangovers..) and in the evening. One evening I spent on recording these guys, as their call is totally different than normal Green Woodpeckers, to me at least. It sounds to me as a hybrid between Green Woodpecker and Whimbrel, listen for yourself:






Faster, higher, 'ki' instead of 'kuh'.. Not even talking about the structure.. But al these questions? When is a Green Woodpecker calling and when is it singing? What types of calls do they produce and when? Do Iberian Green Woodpeckers produces also the 'normal' song (yes they do: http://www.xeno-canto.org/88786) and most especially: is it diagnostic?? I must admit: I don't know.. I can say that this sound (and I only heard this sound, every day for two weeks) is surprisingly different!

Keep recording!!

Friday, 10 August 2012

Mystery bird: the answer and the Pyrenees part 1

Last blog post I gave a sound recording of a mystery bird in the Pyrenees. I've got some reactions, mostly typical species from the higher mountains. I can imagine, as we live in the Netherlands, that we don't have that much experience with those species, but this species is actually a Dutch breeding species! Agreed, not a common one, but still!
It was the call of a Northern Wheatear (Oenanthe oenanthe libanotica)! (Libanotica is surprisingly lighter than the nominate!) I'm totally unsure when the sound is given, I thought begging, but the bird was not a juvenile and other recordings (only a few!) were made for example in April, way to early for juveniles! At first I thought that it had to be specific for this subspecies, but it was also recorded in the Netherlands (by Herman van Oosten). So it must be a rather rare call.



As I said: I've spended my holidays in the Spanish Pyrenees. Hiking, landscapes, birds, butterflies, grasshoppers, plants, lots of fun and lots of friends, thé recipy for an amazing holiday. This time I had to choose what to do. You cannot go for a long hike if you want to watch butterflies or record birds, so every day was different. In total I made about 300 (after selection) pictures and 100 sound recordings (also grasshoppers, still working on them..). All of my Dutch observations and recordings are added to the online database waarneming.nl. Foreign observations and recordings are put on the international equivalent observado.org. Untill recently most of the observations of the latter are done by Dutch observers on holidays, by now more and more observers are putting observations in the database! Wonderfull! I've added all of my sound recordings on observado.org as well (http://observado.org/user/sounds/1246) and for 10 species it was the first recording, yay!

The first week we stayed at Benasque, a small village especially crowded in winter. As the first week in a new country is rather overwhelming, we made quite some hikes and it was windy all the time or there was a stream that ruined the recording. So, I did not manage to make a lot of recordings. When I hear a singing Crossbill (Loxia curvirostra curvirostra) I'm always amazed by the power, melody and variety between birds and populations. Here a bird from Spain, no idea of the type..


One of my targets, Citril Finch (Carduelis citrinella) was heard and seen flying frequently, but the calls were very soft and the birds are very shy.. Ridiculous how difficult they were to see and hear.. Still managed to make a short recording of the (sub?)song, it reminded me of the song of Reed Warbler..


In the mountains I'm always amazed by the melodious calls and songs of Alpine Chough's (Pyrrhocorax graculus graculus) given in stunning flight shows! It seems that they fly just for fun and showing of. My friends and I are struggling to climb that mountain and of course an Alpine Chough is challenging us by flying up and down the mountain with ease...


This where the bird recordings of the first week. The second week we spent time in the Sierra de Guarra, a more quiet area with higher numbers of species and individuals, so more recordings comming up! As said before, I also made several recordings of grasshoppers. Still working on them, but I will spend a blog post on them as well later on.

Saturday, 4 August 2012

Pre-listen from the Pyrenees: mysterybird

From the 7th until the 24th of July I had my holiday in the Spanish Pyrenees with the JNM. Of course I made sound recordings and currently I'm working on them. In the meantime I have a mystery bird that I want to share with you! Eventually we succeeded in locating the sound and thus the species, but we never heard it before. Do you know which species it is only by the sound?



Some hints of the location: open areas without trees and with a lot of rocks. Mainly above 1800 meters, but also one time at 400 meters!

Wednesday, 13 June 2012

'God put a smile upon my face'

In the night of 11-12 June, a midnight 'piepje' (message) announced a calling Little Crake (Porzana parva) in the Weerribben in Overijssel. During the afternoon a plan was made to go for the bird in the evening as we never heard it before and because Alwin is quite busy with a big year. In the meantime, another Western Bonelli's Warbler (Phylloscopus bonelli) was discovered near Arnhem. It's a rather good species for June. The plans were changed last minute once again. Toy picked me up to go for the warbler and we eventually would meet Alwin and Joep somewhere for carpooling.
The Bonelli's Warbler wasn't that difficult to find and identify. Short strophes and an nice 'v' instead of a '^' (checked beforehand on recordings ;) ). When it started calling it became even more easy. I was quite happy with recording the call, didn't hear the last one calling and during my first one I didn't have a recorder yet (I was so jealous of Sander Bot and decided to buy one myself). So a first recording for me!


And of course a recording of the song. Note the second strophe: it shortly introduces the song by calling.


In the meantime it became clear that Alwin was having a diner, so we would meet him at the Crake. We arrived at 21:45 and when walking to the spot, we already got some 'got him' messages! From quite a distance we heard the bird calling. Apparently, my microphone made an impression and immediately the group became silent when I started recording. According Pieter Doorn, my face was priceless when the bird started calling and continued in singing. A big smile appeared on my face, what an amazing sound! Among nocturnal birdsounds, this is absolutely 1 or 2 of the list, competing with Thrush Nightingale.
Note the change in call type when the bird is proceeding into singing:


I made a short walk along the cycle track and heard Common Pochards (Aythya ferina) calling. Never heard it this clear and consious. However, the calls were really weak, so the recording is not that good.


By the way: thanks for all the nice (personal) comments on recordings, I really appreciate that :)
  

Sunday, 3 June 2012

Arctic vs Common Terns

Before I really start, thanks for all the comments on the last blog post on Marsh, Melodious and Icterine Warbler. As a result these notes: be aware of 'slow' Marsh Warblers as they can resemble Melodious quite good and be aware that Melodious can have tick's as well. The recording I made yesterday from a Melodious Warbler in the Netherlands shows ticks, but really is a Melodious (plumage, rest of song). Note that the ticks sound different and are really part of the imitation.


Yesterday (Saturday 2th of June) Toy and me were bird watching with our main goal: moth ticks. As there is an Iceland Gull in Westkapelle, we had to go there. It's a MEGA for June :D. We first 'did' a Common Merganser, dipped the Bufflehead, scored Red Knot (shame on me), ticked Arctic Tern for the year list (more later), hit-and-run for the European Shag and straight to the Iceland Gull. We found out that there was still a Whooper Swan in 't Vroon and ticked it. Ah well, I ticked 10 species for my month list :D


More about the Arctic Tern (Sterna paradisaea). We were driving along the Flauwers Inlaag (near Zierikzee) with our windows open, when I heard Arctic Terns. You might think 'heard'? I know it as the day of yesterday. It was on Texel on the second of May 2009, a beautiful day, perfect birding weather. No, bulls#@#. At least some of it. It was that day that I noticed a different call in the tern-colony. Looked where the sound was coming from and it turned out to be an Arctic Tern. Since that day I am able to identify Arctic Terns by their call. As with my last blogpost, I was thinking about how to describe the differences in calls. To me, Arctic Terns always sound higher pitched and sharper than Common Tern, more 'kie' than 'kah'  and more 'krieeee' than 'kieerâh'. I made sonograms of the different calls and compared them to Common Terns.

The comparison in structure:


Friday, 1 June 2012

The difficult three: Marsh, Icterine and Melodious Warblers

When I was listening to recordings of Melodious Warblers (Hippolais polyglotta) in the Netherlands last week, I realised I didn't really knew handy tricks to distinguish it from Icterine (Hippolais icterina) and (especially) Marsh Warbler (Acrocephalus palustris) on sound only. Yesterday I received the question whether one recording showed a Marsh or a Melodious Warbler. So I dived into the matter. Listened to many recordings on Xeno-Canto.org, noted my thoughts on songs and tried to describe the differences between them. With the risk of making 'mistakes', here my notes (I'm not affraid to make mistakes, so please give comments!):

Marsh Warbler:
Very good imitations, surprisingly often with short 'tick'/'teck'/'zip' notes between other notes. Very upbeat pace and general sounds a little bit mechanistic. Starts sometimes with a Bluethroat-like 'tik tik tik tik tik' and then starts the waterfall of imitations with forementioned 'tick' notes.

Here a recording of Sander Bot on XC. Note the mechanical sound, 'tick' notes and the upbeat pace:


Melodious Warbler:
Clear imitations with clear tones. Imitations often have a longer timespan than in Marsh Warblers. Starts often with 'tretretretretre' or 'tr tr tr tr tr' and then the 'real' song. Pace still quit fast, but because of the clear tones it sounds rather melodious (could that explain the name? ;-) ). Sounds a bit like Blackcap and/or Whitethroat.

As example a recording of Jordy Calvet on XC:


Icterine Warbler:
Very typical for Icterine are the nasal tones which can resemble toys (the type you give to your dog or for in bath). Pace is more relaxed than in Melodious and Marsh.

An example from Icterine by Patrik Åberg (a recordist with many good recordings!). Note the quite awesome imitation of Rosefinch (around 45 seconds) and ofcourse the bath ducks:

As said: please give comments if you feel like I am on the wrong end or if you have additions!


And as a bonus a picture of Melodious Warbler made by Toy Janssen, the guy that learned me watching birds. Visit his site for more pictures during his/our adventures (www.globalbirding.com)


Monday, 28 May 2012

Rosy starling and catching up..

After a few very busy weeks, I finally have time to write a blogpost again. I was very busy with fieldwork in evenings and nights, so it probably isn't surprising that most of the recordings made are from evening/night active species.
A few weeks ago, on a normal afternoon, I was monitoring House Sparrows in Pijnacker between greenhouses when I suddenly realised I just heard a Wood Warbler (Phylloscopus sibilatrix). A complete strange location for a breeding bird, so it had to be a migratory one. With the realisation that it should be a rarity in this area, I made a (poor) recording for proof. It turned out to be one of the few observations in the muncipality, lucky me..


On the 9th of May we were supposed to meet for the last preparations for the big day. Together with a housemate we have done shopping and were already cooking. I almost died of hunger, but when a Red-throated Pipit (Anthus cervinus) was discovered only 5 minutes from my house, we (Big Day team) immediately ran away, leaving my housemate shocked with half cooked diner. She finally saw how a twitch happened and how I 'suddenly' overcame my hunger :).
It was windy and the bird sat far away. Sheltered by a car, I made a recording of the flushed bird which called only once. The joy of the local birders and sheep is clearly audible ;)

Another adventure in the evening and night at the military area last Tuesday. In my first round in the evening, there were about 30 Common Swifts (Apus apus) swirling around a building. Adults were screaming from out of their nests, a wonderful sound and typical for those warm evenings. Maybe that's why I love them?


The same evening, although a couple hours later, a few juveniles of Long-eared Owls (Asio otus) were bothering their parents with calls for food. A total of eight juveniles were calling, I think it should be from two nests. Will the parents notice the difference between theirs and others kids? How to feed them all! Note the variation between calls:

I almost catched up with my recordings. Yesterday, supposed to be a relaxing afternoon with a picknick, changed into an afternoon birdwatching as an adult Rosy Starling (Pastor roseus) was discovered near Hilversum. We haven't had that much records of adults and for many, including me, it was the first time. I just installed myself with my recording gear (in case of) and sat in a sheltered position when I saw the bill opening and closing through my telescope. I recorded it and only after a while (after my recording), other observers noticed that the bird was singing. Me and another recordist approached the bird to capture a beter recording, but the bird flew away (not because us). It never sang again! Another first for Waarneming.nl and only the fifth for Xeno Canto! The bird was on quite a distance and sang very softly, so I appologize for the noise, but you can hear it clearly. Quite different from Common Starlings isn't it?

Later in the afternoon we went for a Common Rosefinch (Carpodacus erythrinus), but because of the wind, I couldn't get more than a record 'shot'. I indeed was 'pleased-to-meet-you'.

Pieter Doorn and Alwin Borhem are busy for a big year and they really are on a good schedule and very close to each other. In the evening, we had diner for 5 and went for Common Nightjar (Caprimulgus europaeus). I failed to record the awesome sounds of Nightjars ('tjoek tjoek' and the stuttering end of the song), but I managed to make a decent recording of the normal song.

In the near future I will write a blogpost of different calls of Reed Warblers and Tawny Owls :)

Thursday, 10 May 2012

Nightingales!

This blogpost I will leach on recording of others (many thanks for that!), but I think it will be worthwile when you want to learn something about the difference between the two species of nightingales, using the thriller. For several days, Tim van Oerle heard a Nightingale singing near Zevenaar. He made a recording because is was not sure of which species it was. It had an 'thriller' and as most of you will know, this is typical for Thrush Nightingale (Luscinia luscinia). He still had doubts, because the song was rather quick. The recording can be found here:


My first impression was Common Nightingale (Luscinia megarhynchos), however: why? It indeed had a thriller. So I decided to dive into the matters of nightingales. I looked for several recordings on www.xeno-canto.org for both species. I found these two very useful. The first one was of a Common Nightingale in the Germany, recorded by Claus Fisher:

And this recording of a Thrush Nightingale of Jarek Matusiak:

To look for the difference in structure between the rattles, I composed an audiofile with all three rattles and made a picture of it. The structure is quite different:

















Sorry it's in Dutch, but from left to right: nightingale spec, Common Nightingale and Thrush Nightingale.

As you can see from the picture, Thrush Nightingale has two short 'notes' after each other, whereas Common Nightingale has one. This gives the Thrush Nightingale a more crackling rattle. Furthermore, (although not visible on this picture), the song of the nightingale of Tim was fast and missed the characteristic deep and low sounds that makes the song of Thrush Nightingale makes it possible to listen to it for several hours!

Conclusion, it has to be a Common Nightingale, but at least I've learned something! If someone has any comments on this, please give them!

Wednesday, 2 May 2012

Western Bonelli's Warbler

This morning a Bonelli's Warbler was discovered near Arnhem in Westervoort. As I never heard a Bonelli's Warbler (Western nor Eastern) singing, I was eager to go for the bird. The song and the call of the two species of Bonelli's Warbler differ from each other, so this would make it interesting for soundrecording.

First some recordings:

A long recording with 4 trillers.


A recording with 1 triller. And here the corresponding sonogram:

 







And a recording of 1 trill which was slightly different from the other ones. I only heard it once. And also its corresponding sonogram:








Now, the identification of the species. I would like to refer to the (excellent) article of Dick Groenendijk and Teus Luijendijk (Dutchbirding 33: 1-9, 2011). They give a table of key parameters which distinguish the two species. The first parameter is the shape of one note. An upright 'V' for Western and an inverted v or '^' for Eastern, here obviously an upright 'V'. The second parameter is the last part of one note of the trill. This should be a / in Western and a \ in Eastern. Also this points to Western. The maximum frequency is 7200 Hz for Western and 6300 Hz for Eastern. In my recordings I come at an average of 7000 Hz (n=18), so again Western. I guess the ID is already known, but we will check the last two parameters. The average numbers of notes per trill in this bird is 10 (+/- 1). For Western this would be 9 (+/- 2) and for Eastern 15 (+/- 4). The lenght of the trill is 0.53-1.24s in Western and 0.71-1.70s in Eastern, in our bird this is 0.657-0.812.

Awesome birds, and I am really happy that I saw and heard the bird. To bad it didn't call, but now we could use the referred article in practice ;)

Sunday, 29 April 2012

Bird of the day: Grasshopper Warbler

Today was a calm day, almost no wind, no sun but still warm. As Wageningen is quite religious and it was cloudy, there weren't many people around the Nevengeul: almost perfect conditions for sound recording. So I did!
There were a lot of Common Whitethroats, but almost everywhere other birds were screaming through their song. Too bad, no (good) recordings of this species today. While listening to the Whitethroats, I heard a Grasshopper Warbler (Locustella naevia). So I tried this one, and it was more cooperative! It even started singing totally in the open and showed really well. A Blackbird was desperately trying to overrule the bird, but as their song has a lower pitch, we are able to shut their beak (figuratively of course)..


This reminded me of recordings I made of this species last autumn on the island of Vlieland. I think I've recorded almost all types of sound that Grasshopper Warblers can produce, except for the begging call. But birds can always surprise you!


On the 22 of August 2011, I was birdwatching with Marijn van Oss and Jorrit Vlot on Vlieland. I found a Grasshopper Warbler in some scrub, but it started to sing very softly and a little bit hastily. As the shutters of Marijn and Jorrit's cameras were clicking and the bird flew away eventually, I only made a short recording. It was recorded without pistol microphone:


The same day, more in the afternoon. I heard a loud and sharp 'tsak' comming out of the scrubs. These scrubs are closed from above, but you can watch through them when kneeled. So I tried to lure the bird into my direction by imitating the sound and the response was curiously comming more nearby. Eventually I got a view on the producer: a beautifull 1cy Grasshopper Warbler. I made a recording, again with the recorder only, but this bird was so close!


Admit it: it is a sound that certainly draws your attention when bashing some bushes in autumn!

Sunday, 22 April 2012

Savi's Warbler's old diesel engine is starting

Today, Sjoerd, Mark and I were doing some monitoring for the national Big Day (already in 3 weeks!), so we went to the Maashorst for our forest birds, check a location of Middle-spotted Woodpecker (with succes) and check the location for Crested Lark (also with succes). As the weather was quite precarious (sunshine and hail switched turns...), we decided not to go to the Biesbosch for more checks. Instead, we saw on the internet that next to the Crested Lark there was an area where Savi's Warbler (Locustella luscinioides) was heard singing for almost a week already. As this bird can be difficult sometimes, we would like to have a back up during the Big Day. This was a welcome one, as it was 1 minute off route.

It turned out to be an easy individual which was frequently singing and chasing a female. It was the first time I observed a Savi's Warbler start their song. The motor in their throat has to start like an old diesel: "raket-tak-tak-tak-tak-vrrrrrrrrrrrrrrrrrrr"

Sunday, 15 April 2012

Jack Snipe and more!

This year, Sjoerd Radstaak, Rutger Wilschut, Mark de Vries and I are doing a national Big Day (see as many species of birds in 24 hours in the Netherlands). The first time for me, so I'm pretty excited. We are planning to 'do' our forest birds in the Maashorst, my former local patch (now I moved). A big day requires some research in advance. As we have planned our route via a lot of known places, most of the research can be done on the internet. The forest species however are more difficult: you have to know exactly where which species has their nest or singing post, or at least a small area where the change is practically 99,9% of encountering the species in 1-2 hours in half May. Today I went to the Maashorst to monitor some difficult species. There were some simple year-list ticks of species that shouldn't be a problem on the big day: Common Redstart, Cuckoo, Pied Flycatcher and Tree Pipit (shame...). As the Common Redstart (Phoenicurus phoenicurus) was singing pretty loud, I made a recording. To bad that in spring there is always a Willow Warbler (Phylloscopus trochilus) ruining your recording. This one waited untill the Redstart was finished with its strophe. The Redstart is succesfully imitating a Treecreeper!


15 minutes later I found a nest of Northern Goshawk (Accipiter gentilis), pretty good one for the big day! Also I heard 3 Lesser Spotted Woodpeckers (Dendrocopos minor), two couples of Bullfinch (Pyrrhula pyrrhula) and found a couple couples Long-tailed Tits (Aegithalos caudatus), a surprisingly difficult bird in May!


The last week, we have had quite some Ring Ouzels (Turdus torquatus) in the Netherlands. The Maashorst had quite a few as wel, with 39 individuals at one time last week! During my walk I bumped into 1, 1, 15, 3 and 11 individuals respectively! The wind was pretty strong, but I managed to make one recording of a calling individual from out of a tree, which provided me the shelter against the wind:


And then the 'highlight' of the (recording part of the) day: I flushed a Jack Snipe (Lymnocryptes minimus) Sometimes, pretty rare actually, Jack Snipes are calling when flushed. This individual did! And, I had my recording gear running!

It is not a good recording, but hey, for the first of waarneming.nl and xeno-canto.org it is not that bad! You first hear wingbeats, then a soft call ('wêh') and than some noise from my bag. Yay!

Wednesday, 4 April 2012

A normal day at work...

As already mentioned, my work consists of watching birds, bats, looking for fish et cetera. Last monday 2 april, my task was to look for protected birds, mainly birds of prey, on a military area! After a long hassle at the entrance (you have to announce you are coming), checking the address, checking the passport and that kind of stuff, we finally could enter the military area. My collegue isn't that much of an expert in bird(sounds), so he came along to learn something from me. He had troubles to hear the sound I mentioned between the other sounds. But the Willow Warbler (sounds like a Chaffinch where the battery has run out) sticked into his mind :).
I heard quite some Bramblings (Fringilla montifringilla), which was not that common in this winter. In one place, we heard about 30 Bramblings singing. At least, thats what I know now. I didn't knew the song of Brambling so far. It is a Greenfinch-like, piercing 'wêêêh'. As the recording isn't that good (only recorder, no shotgun-mic), I only put it on waarneming.nl and not on Xeno-canto.org:


In another part of the military area, two Northern Ravens (Corvus corax) were present. One individual (presumably the male) was calling from a tree, not really taking notice of us. Sharpening his bill, hopping from branch to branch (and thereby breaking the branches) and now and then calling. A second individual (the female) was more nervous and flew rounds. As I almost stood under the tree where the male was calling, I had to made a recording. It was my best sighting of a Raven ever and I was quite happy with it!