The VisMig Files #2; Early May at Tyresta National Park

Wild Bird Acoustics brings you two sound magazines in this episode. As Autumn now stretches out in front of us, I thought this might be a good time to include the second installment of passively recorded audio from my listening station at Hällögern in Västrbotten. Podcast listener's will now be very familiar with this location, but this will be the first time I will share audio from the late autumn period at this site. In 2024, due of the aqquisition on a new SM Mini recorder for this site, I was able to passively record for a significantly longer period of time, which allowed me to collect audio all the way into mid November. I will share the results of that passive deployment with listeners in this sound magazine.

The second half of this episode concernes itself with field recording at Tyresta National Park in early May. Having recorded there extensively throughout early spring, it was wonderful to get out into the field and experience new sounds in the park in May, those of newly return summer migrants. It is during the late spring period that many breeding species return and reclaim breeding territories at this site and I was on hand to get some lovely audio as this began to happen in 2025. Join me as I share some wonderful audio of a wide range of species, as summer species began to flood back into Sweden.

Transcript

 You are all very welcome to Wild Bird Acoustics. I'm your host, Alan Dalton, and I'll be taking you on a journey into sound.



Welcome everybody to Wild Bird Acoustics once again. It's been two weeks already and the autumn is now upon us my favorite time of the year, and I absolutely love getting out in the autumn. Just recording passage migrants, and visible migration as often as I can.

I hope you're all gonna have a wonderful autumn and you enjoy your birding folks. Now I'm not gonna talk too much in this introductory section. I'm just gonna get on with the first Sound magazine and seeing as it is Autumn, I thought we would get into the vising files audio here from 2024 from my main recording device, which is out on the coast of VAs Botten in Northern Sweden.

This is the Smic files. Have a listen.

 Welcome to Wild Bird Acoustics. Once more, it's the Vis MIG files once again, folks. And again, we are going to be concentrating on the island of Polygon along the coast of VA Botten in Northern Sweden in autumn, and I have some wonderful audio to share with you from the autumn of 2024. Now this is the second little magazine I've done about 2024 on the island in autumn, and all of the audio, you will hear it.

And the sound magazine was recorded with a sound meter, two mini recorder, a fantastic little device. I did a little review of this device on my blog in January of 2025 if anybody is very interested in this device, but I would certainly recommend them for autonomous recording if you want to set up a listening station somewhere.

I really would recommend that you use this device, and that is down to a number of factors. The extremely long battery life, it's completely weatherproof. It's very, very easy to program, and I have found them 100% reliable in all situations today to over the last several years. So a strong recommendation for the wildlife acoustics SM mini recorder.

Now we're gonna move along folks, and we'll get straight into the recordings. Now the first recording I have for you is of missile thrush, one of my favorite species. I absolutely love rattle call of this species in autumn, and in this recording, the bird is right beside the recorder is sitting in the rowing tree where the recorder is actually placed.

There's loads going on here in the background as well. At the beginning you can hear passing, parted, cross builds, great hit and other tit species. In the background, there's the call of Golden Eye. I think at one stage some sort of a feeding woodpecker, possibly great spotted, but it could be a number of species.

There's a singing chip chaff on the mainland calling field Fair. And also the quiet calls, the high call of song thrush in this recording, but the main species here is missile thrush, the wonderful rattling call of the species. Very typical autumn sound.

One more recording of missile thrush before we move on from these species. This one taken on the 8th of October, 2024. It was quite a windy morning. You can hear the foliage being moved around in the background. As well as the waves from the Baltic Sea. So a nice bit of ambiance here in the background and some wonderful audio of missile thrush.

The rattling call of the species as they pass overhead on migration. Early in the morning. Have a listen.

Now, 2024 was the first year I actually got microphones down right into November, and as a result I got some lovely audio of some species I have been after for a while. The next recording is quite short. It's of gray headed woodpecker, a species that proved quite active in early November. I'm gonna play a little recording now of a bird flying over from the mainland onto the island, just giving some call.

It's quite a nice short recording. This is gray headed woodpecker.

Now I recorded the right into November and one of the species, in fact, these species I was most interested in was pine grass beak. Now Vata Botin is a good place for these species, and I had never recorded them to date in October, so I was very, very keen to get microphones down right into November and see if the birds were moving down the coast.

I had no idea if this was actually going on, but in 2024, I got my first audio of these species, and the first recording came on the second November, 2024. I'm gonna play that recording now. Listen carefully. This is quite subtle. And in the background you will hear a pine grass beak just moving along the coast, giving some call.

Now, pine Gros Peak, of course, is a northern special E. It's a very, very scarce species in Europe. It's wanted by a lot of western poly aortic borders, and in order to actually see the species in Europe, you pretty much have to go to Finland or a very small area in Northern Sweden. Quite a difficult species, but it does tend to erupt in certain years, and they definitely do move in the late autumn time and early November is an excellent time for the species.

Now on the second November, I got a number of calls. I'm going to play another call type. Now this carefully, again, quite subtle, a little bit distant, but this is Pine Gras. Be at Halligan in Sweden.

Now, a few days earlier in late October, I got this recording. I was very, very happy with it. And in the background here, you can hear some song Thrush, field Fair, and Other Species still around even this late in the year. But if you listen carefully here, you can hear the wonderful calls, the very distinctive calls of pine grass beak just moving around on the mainland.

A quite wonderful recording.

No. No.

Next up for you. Have a wonderful recording of song thrush, an alarming bird, right on top of the microphones. You can hear the bird just flying in and starting to give some a deep alarm calls. I'm very interested in these calls by Thrush Beat. I think they're quite wonderful and I'm gonna play a song Thrush first.

We'll probably compare that with Red Wing just a little bit later. But first up, this is Song Thrush, A Bird flying in, starting to give some alarm calls. And it is answered by another bird in the distance in the beginning of this recording. Quite a wonderful recording. Again, a little bit of road noise in the distance, but the bird is so close to the recorder, it doesn't make a great deal of difference.

This is alarming song Thrush.

Now we'll move on to Red Wing straight away and have a lovely recording now of some alarm calls from Red Wing. This bird seemed a little bit anxious. It's giving more regular calls for us before breaking into a little bit of alarm call, which gives it away. Sometimes these calls are quite difficult to discern.

Song Thrush and Red Wing, they sound quite similar when they're alarming, so I thought this would be quite useful. I'm gonna play the recording now. There's quite a bit going on in the background. You can hear plenty of Fieldfare, for example, as well as some Willow tt, which is nice in here in the background.

But this is alarming Red Wing.

Another nice recording for you. Taken on the 5th of October, 2024. There was stacks of Red Wing in the area on this particular morning, and I got this nice little passage of alarm call from a board that was quite close to the recorder. Now I was very happy to get close alarm calls of Red Wing, such as this recording in 2024 to my year.

That sounds remarkably similar to something maybe Ring Ule might give. So it's quite interesting to me. So once again, folks, this is alarming. A red wing, very, very close to the SM Mini recorder on this occasion. Have a listen.

Now, I'd never recorded into November before and I was quite interested in what I might pick up and one of the species. I actually didn't really expect in big numbers was Eurasian Tree creeper, but actually they were going through in very, very good numbers, especially in late October and early November, and this surprised me a little bit at that time.

Quite often there was very little else on the islands, so it was nice to get recordings of these species. I'm gonna play a very, very subtle recording first. It's quite a windy morning. Very, very late October, and the only bird you will hear in this recording is Urian tree, creeper bird, probably just moving along the coast of the island, feeding away quietly as it moved southwards along the coast.

I just love the idea of these birds just quietly moving down the coast in late autumn, undetected by borders, and the calls are quite subtle sometimes, as in this recording. I'll play this one first. This is late October Tree Creeper at Halle Garn in master button. Northern Sweep.

Another recording now taken on the 24th of October, 2024. A little bit closer to the recorder and not quite as windy, although generally speaking in late October it was fairly unsettled. This is quite a nice recording. Once again, this is your Asian tree creeper at Halle.

The next recording from the 14th of October, 2024. A little bit more settled to some Jay Field Fair and other words in the background. We'll listen for the very, very high calls of a Eurasian tree. Creeper quite close to the recorder once again on this occasion. This is a very nice recording.

Now they can be very, very subtle. Eurasian tree creeper. I've been wondering quite a lot actually about the species as an nocturnal migrant. I've certainly never seen them on visible migration at any point in my life, and I figure they have to be a nocturnally migrating species. Quite often when you get up in the morning in darkness, you'll hear them in the trees around the island and I figure they must have arrived during the darkness.

They seem to be completely silent at night on active migration, so I'm just quite interested in the species from that point of view. They are certainly very, very vocal once they land and begin to feed, but it can be very, very subtle now in this recording, taken on the 16th of October, 2024. There are some single calls from a tree creeper, but it gets more active from about a minute onwards when you can hear the bird flitting around.

Very, very close to the recorder, and it gives several calls towards the end of the recording, which are very, very clear and discernible. Once again, Eurasian Tree Creeper.

Now one more of Tree Creeper before I leave you. This is quite a typical scene of the island in late October. And in the background you can hear a red wing and field fair, just very, very busily calling. They're moving through in numbers at time of the year, but if you listen very, very carefully, it's quite subtle.

You can hear a number of tree creeper just feeding in the background very, very quietly just going about their business as these species does. It's a very, very common migrant in this part of the world. Of course these Scandinavian birds look a little bit different. Two birds in the UK and Ireland, much cleaner on the under parts.

Snow white and quite beautiful little birds in their own way. Now vocally, a very subtle species in autumn, easily overlooked in among flocks of tits, which they often join in the autumn and the winter. So quite nice to get some vocalizations of the species recorded. So we'll have listed of the recording now.

Like I say, very, very subtle. You should be wearing headphones for this and see if you can pick up the E Erasion tree Creeper in this recording.

Now if there's anybody out there just wondering whether I get to identify everything I hear when I record autonomously. I certainly do not, and next recording is a case in point. Effectively, it's an unidentified file of a very high call. I'm pretty sure it's a pass, Ryan, not a hundred percent, but it's very, very annoying not to know sometimes what these words are, particularly when the recording like this one is of reasonably high quality.

I have been wondering whether this could possibly be a gray wagtail, but I thought I'd just put this out there just to actually make the point. You'll not get to identify absolutely everything. You'll hear in your audio and it's quite normal. So this is one of those unidentified files. Have a listen to this.

Like I say, if anybody out there knows what it is, do let me know.

So there you go. A mystery recording. Not entirely sure what that is. I have often wondered as well, is a chief chaff of some description, perhaps an eastern bird, just giving squeaky calls. I'm really not sure. Like I say, answers on a postcard or rather to world bird acoustics@gmail.com if you actually know what that is.

Now we're gonna move along, and the last recording I have for you is the wonderful, wonderful call of Bohemian Waxwing, the doorbell call of the species, recording well into November. You get plenty of these birds moving through and it's quite nice to record the species. Hey, rather short recording. Quite a nice recording.

This is a wax wing.

So there you go folks. That's another sound magazine done and dusted here at Wild Bird Acoustics. That was a tunnel sounds the vis files from Vastar Button in Northern Sweden. All audio recorded with an SM mini field recorder. In the autumn of 2024. As always, folks, thanks for cheering in. It's been great to share this bit of audio with you and I hope you have enjoyed it.

We'll see you next time. Folks at Wild Bird Acoustics.

So there you go folks. That's the Vis MIG Files from Vast Button in Northern Sweden.

I hope that will wet your appetite for getting out into the field this autumn, and recording some passage migration.

Now we're gonna move along and once again we're gonna get into the tourist de files. As you will know by now, I was out in early spring in tourist to National Forest and it was an absolutely incredible experience. I did cut it short in April, but I did get out briefly at the start of May at the park when things had transformed quite a bit, and the first summer migrants were just coming back onto territory.

Did a bit of recording and you will hear the results in this next sound magazine. This is the tier de files early May at Tier National Park.

 Now welcome everybody to another sound magazine here at Wild Bird Acoustics. We're gonna be focused on a single day outfield recording at Ton National Park. The date was the 1st of May, and on that particular date, I found a range of lovely birds singing at the park. Several of them newly returned migrants, and I got some absolutely wonderful recordings on the day, and I wanted to share those with you guys today here at the podcast.

Now what I did was on the day I decided to actually explore the far northeast of the park and in this area you have an area called Tears slot, which is excellent for water birds. There's some nice re beds there too. There's a lovely stream called fall brink strum. I checked that out as well. Then I wandered up the hill into the park proper up to an area called Fat Buren, and then I just moved through a very large open area I had never been to before.

And it was very, very interesting and I got some lovely recordings there as well. Now these recordings were too good to actually just skip over, and I decided to put a small cell magazine together and I thought this would be a nice compliment to the tiers to files, which have already put together several longer cell magazines of about an hour each.

So I hope you enjoyed these recordings, folks. We're gonna dive straight in.

Now, as stated earlier, I went to Tears to Slot first. And just began to move around the area with the Tinga Pbla, and the first thing I came across was a pair of common sandpipers in display. There was a wonderful backdrop in the park singing wood pigeon on a lot of Blackbird in song, quite a short recording.

I'll play that for you now. This is the display of common Sandpiper on the 1st of May, 2025.

Now as usual, it didn't take me long to just relax completely. And just begin to kind of follow the sounds I was hearing. And this just led me from one bird to another. And this is quite typical of recording in spring when there's a lot of birds on territory singing. The next bird that attracted my attention was Eurasian re just belting out song, and it always amazes me how loud these tiny little birds are.

And here's a nice recording, quite short, about a minute and a half of Eurasian ran, just giving some wonderful, wonderful song. There's a nice backdrop here. Species like Robin and Blackbird, which I'm sure you will all identify quite easily at this stage, but the main species here is Eurasian ran a wonderful song even though it's a very, very common species.

Have a listen to this.

Now, quite often when I go to a site, I might have a particular species in mind, and so it was in this particular day is a colony of great crested GREs at tears to slot. Quite a big one, about 30 to 40 pairs. And it's a species I don't have a great deal of audio for despite the fact they're quite common breeders here around Stockholm in Sweden.

And that was something I wanted to address on the day. So what I did was I set up my Pele. And just settled in quite close to the colony. And what I wanted to do was just get some audio of these great crested grapes. They're quite noisy when they get back to the breeding areas and they were busy kind of mating, building nests, courting, all that kind of thing.

I've got a lovely recording now for you of some great crested grapes just from the bridge at tourist the slot, and I'll play it for you now. This is a great crest of GREs, just going about their business, quite moly, on the 1st of May, 2025.

Now it was quite wonderful just sitting there, just taking a all in, watching these birds display, doing their mating dance, feeding each other, building nests. They're wonderful birds to watch. And I got a number of recordings. I'm not gonna play them all for you. But I will play one more slightly shorter recording than the last one.

Once again, this is Greg Crested GREs. There was a road in the background, but because the birds are so noisy and they were so close to me on the bridge, it really wasn't that intrusive, and I got some lovely recordings as a result. Once again, here's a recording of Greg Crested GREs on the braiding grounds.

A wonderful recording materials to slot.

Now I'm not quite doing great Crested GRE in a way, and I have a little kind of opportunistic recording here for you. And whilst I was actually recording the great Crested Rebe, there was a pair of mutes, one also breeding in the area. Now the email of the pair, as they often do, was just keeping an eye on me and it made several calls and I managed to get a recording.

So in this recording, after about 10 seconds of Great Crested Grebe. You're gonna hear the calls, the quiet calls of a male mute swan. I'll play that for you now.

Now time is moving on slightly and I'm always conscious of time. I like to get out early in the morning and the first traffic was beginning to appear. So what I did was I quickly checked the stream at F Spring, strumming looking for dipper, no success there. And then I made my way up the hill into an area called Fat Bur.

Now I was quite surprised to find some breeding little grape here at Fat Bureau, and this wasn't a species I'd found at this location in previous years. Also, on the lake were some golden eye and they were displaying as well. I tried to grab a recording very, very quickly. It was quite noisy due to some gray like geese in the area.

I'll play the recording. Anyway. You're gonna hear some displaying golden eye here. Also, listen now for the display of little gr far in the background and some rather noisy gray lag geese.

Now from this point onwards, I was all about looking for new migrants in singing birds, and one of the first I found up around and beyond Fat Buren was this wonderful willow warbler in song quite a few days on the day. And this was the best recording I got with the Tinga para. Always nice to get these birds back in numbers in Spring, and as I say, I'm at a number of recordings of these species.

I'm just gonna play this one. This is probably the best recording I got on the day. This is Willow Warbler in full song on the 1st of May.

It is always wonderful to get out at this time of the year here in Sweden in pretty much any quiet habitat, and that was the case in this particular morning. The next species I came across was a singing tree pt. It was just sitting up in a tall bear to occasionally doing some parachute song and some flight song.

Quite wonderful to behold, and I got a reasonable recording. So this is Tree Pivot once again. The northeast corner of Tier National Park.

Now the next recording I have for you is quite interesting. When I heard of, first, I assumed this was going to be a garden warbler, and when I got closer and actually got eyes on the bird, I realized it was actually a male black cap. Now these two species still give me trouble. This is indeed a well seen male black cap in song.

I got a nice recording. It's just over a minute long. I'm gonna play it for you now, but a particularly flutie sounding bird. Quite often they sound a bit scratchier and this bird sounds quite like a garden warbler. I think I need to do a little bit of work myself and fine tune my ear for these two species.

Next year. I want to get out and record a lot more of their songs. I did record a lot of Garden Warbler songs in 2025, which was very, very nice. But they can be quite difficult not to be taken lightly. And like I say, this bird just struck me initially as being like Garden war player. I'll play it for you now.

Interesting song here from a male black cap. Had fat urine in theist.

Now the next recording I have for you is one of my favorite species, European pie fly catcher, a wonderful cock, bird giving full song here, particularly nice male, very black and white. Obviously an adult male, and I got very, very close to this bird as it sang above my head, and as a result, got a lovely recording.

The bird typically was singing in a small garden beside a cabin in a little area of kind of quiet houses. And very, very typical habitat for the species. They seem to love gardens like this. This is a wonderful recording of European pie, fly catcher.

Now the next species I have for you is not in fact a migrant species. It's a resident species, but it is one that always grabs my attention when I hear the when a mountain spraying and that is lesser spotted woodpecker. They're just fantastic little birds and I just can't get enough of them in this recording.

It is the drumming of the species. The bird is in full display. And I got a wonderful little recording of this bird drumming quite often, quite easy to separate from greater spotted woodpecker. Little bit higher in timber, certainly a lot more rapid, the drums of the species. And you'll hear that in this recording.

This is the drumming display of lesser spotted woodpecker.

Now folks, I have saved the best for Last for you and this is a wonderful recording. When I heard this Bird in song, I know it was something I wanted to spend a little bit of time on. I wanted to get this recorded as well as possible. It's a male common Red Start in full song. Now common red start is species I really wanted to concentrate on in 2025, and the reason for that is they're excellent mimics.

I actually got out and recorded several birds in the spring of 2025, but this was the first one I came across this spring, and I was delighted with this one. I got a lovely recording in the end. I had to make several efforts at this as on occasion a car would go past after a minute or two and ruin the recording.

And I wanted to get at least five minutes of this bird in song without being disturbed by any kind of anthropogenic noise. I'm gonna play about three minutes of this bird now. It's a wonderful, wonderful songster. Listen carefully and see if you can pick out some memory for yourself, but this is common Red Start A stunning adult male in full song in Northeast Tier National Park.

So there you go folks. That's the wonderful song of Common Red Start in Full Song and absolutely wonderful, wonderful Songster. It just goes to show folks all of that came from one morning in the fields and Spring naturally is an incredible time. For the field recorder, I would urge you to get out as much as possible in spring and honestly, one morning in the field at that time of the year can easily yield sort of 10 to 20 good quality recordings, so very, very much worth prioritizing your time in spring.

That's all for me here at Wild Bird Acoustics. I hope you have enjoyed this sale magazine and we'll see you again soon folks. Thanks for tuning in.



And just like that time is up once again here at Wild Bird Acoustics. That's the second sound magazine for you. Tears to National Park in early May. An absolutely incredible place to be, an incredible place to field record birds.

And I hope you have enjoyed this series in season three of Wild Bird Acoustics. Now, just before I go, I would ask you once again, folks, please to spread the word on the podcast. If you know any birders who were interested in bird sounds, if you've been enjoying the podcast, just recommend it to as many people as you think might be interested and spread the word.

It would be wonderful to get the podcast out to as big an audience as possible. It's a lot of work, and it would be great to reach more ears. I thank you for your efforts already, and for now folks, I'm just gonna say a Jew, and we'll see again in a couple of weeks here at the podcast.

That's all from me, Alan Dalton here at Wild Bird Acoustics. Stay tuned, folks.

 So that brings us to the end of another episode of Wild Bird Acoustics, and I hope you've enjoyed it. As always, you can find us on YouTube by simply searching for wild bird acoustics. We do have a mailing list also, and if you want to be part of that folks, you can drop us an email at Wild Bird acoustics@gmail.com.

Now all feedback is greatly received here at the podcast. And if you'd like to write review of the podcast, you can do so at the buzzsprout header page. In addition, if you'd like to make a small financial donation to the podcast, you can do so using the buy me a Coffee button, and you'll find that also on the Buzzsprout header page.

We will be back in a couple of weeks with more from wild bird acoustics. Until then, take it easy, folks, and as always, don't be afraid to get out into the field and relax and just listen to the wildlife out there. Maybe even do a little bit of field recording of your own. We'll talk to you soon, folks.

Take it easy. That's all from Wild Bird Acoustics.