Sunday 11 June 2023

Savi's Warbler

At around 9.45pm on 31st May after having taken a small Devon Beaver Tours group to see our local beaver population, I arrived at White Bridge and was saying goodbye to everyone when I thought I heard a brief Savi's Warbler singing!! I said my goodbyes as quickly as I could and then headed closer to the reedbed not truly believing what I thought I had heard. Then, I heard it again, a Savi’s Warbler on the patch!

Almost in disbelief, I made the following recording on my phone using the Merlin App:

Despite the bird being very close, I never actually saw it and concentrated on obtaining a recording rather than using my binoculars as there was very little light. I returned the following morning at around 5am but there was no sight nor sound up until around 7am, so I assumed it had simply moved on.

1st June Evening
I had another evening beaver walk and returned to White Bridge at 9.50pm and amazingly, the bird sang briefly again, but similar to the previous evening, it was just giving very short reels. This time I recorded the bird using video on my phone below, but again did not see it other than in my thermal camera! However, I did manage to leave out my sound recording equipment at the site.

In the above video, you can even hear the "start up" notes preceding the "reel"

2nd June Morning
I returned very early the following morning but once again there was no sight nor sound, but on checking my sound recorder I discovered the bird sang very very intermittently between 03.25hrs and 04.13hrs when my battery died.
The final time I heard the bird with my own ears was on the evening of the 2nd June when it simply gave a total of just three very very short reels at 9pm and 9.30pm.

3rd June
Below is one of the longest continuous songs that the bird gave, but again, only ever giving very short reels. It was recorded using equipment left overnight on the 2nd/3rd. It mostly sang very, very intermittently (mostly for just a few seconds) between 03.07hrs and 04.38hrs. Despite leaving my sound recording equipment out for the next few nights, this was the last time I recorded the bird on site. The recording below was at 04.33hrs 3rd June

It was very exciting to find such a rare bird on my local patch, but I did feel very frustrated!
1 - I never saw it, other than a thermal red blob on my thermal camera!😂
2 - Nobody else was likely to ever see it because it never sang in daylight!
3 - I was unable to release the news far and wide as it was in suitable breeding habitat and behaving quite strangely in terms of not ever breaking out into "full song". Some literature even suggested “short reels” were sometimes indicative of breeding activity.

In hindsight, with the bird now gone, it is perhaps easy to say I could have released the news?
I always get a buzz when I find a rare bird and for me, much of that buzz comes from sharing the excitement when others can enjoy the bird too. However, the bird's secretive behaviour, late time of year and reluctance to sing fully (possibly suggesting breeding) made me cautious. Also, let’s be honest reedbeds in the UK have been producing all sorts of exciting breeders in recent years, so stranger things have happened! Then there is the advice from the Rare Bird Breeding Panel which made it clear to me that the responsible thing to do was to keep it quiet.

The RBBP believes that Savi's Warbler are one of a number of species that are:
"especially vulnerable, and we suggest that no records of these species in circumstances suggestive of breeding or potential breeding habitat are shared in the public domain during the breeding season, unless public viewing has been arranged."

Previous Savi's Warbler Records from the Otter Estuary:
1979: 22 April and 4-8 May
1990: 28 April

Most recent Savi's Warbler records in Devon
2012: Exe Reedbeds 11-25 June (20th Devon record)
2013: Mansands 30 May (21st Devon record)

Savi's Warbler - Sadly NOT the Otter Estuary, but from Armenia in May 2023

Savi's Warbler sonogram taken from 3rd June recording, Otter Estuary

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