Migration at Portland Bird Observatory

I was lucky enough to have the opportunity to stay at Portland Bird Observatory for a week during peak spring migration in April. Due to its proximity to the English Channel, Portland is just about the best place on the South Coast for watching spring migrants arrive in Britain.

It was a bird-packed week...

On the first morning of my stay, I went into the observatory garden just before 6am to be greeted by huge numbers of passerines flitting about and feeding in the shrubs. Unbeknown to me, there had been a large 'fall' of migrants during the night, resulting in 1000's of birds dropping onto Portland from their migration. There had been heavy cloud and fog during the night and early hours, which meant that any birds who were migrating across the English Channel wouldn't have been able to navigate and so dropped down onto Portland.

This male Pied Flycatcher was one of many birds which arrived that day; very conservative estimates included 4,000 Willow Warbler, 1,500 Blackcap, 130 Wheatear, 40 Whitethroat, 35 Grasshopper Warbler, 30 Sedge Warbler and 25 Redstart. It was amazing to see bushes fit to bursting with birds and I felt very lucky to have been there and witnessed it.

Here's a female Pied Flycatcher, who had just arrived in off the sea.

They undertake a journey from West Africa, heading through North Africa, Spain and France, before crossing the channel and arriving in Britain. From here, they will stop off for a few days on the South Coast, before moving northwards to breed. 

This male Whinchat will have followed almost the exact same migratory route as the Pied Flycatcher.

One of the best places to see migrants was on the Top Fields, just above the observatory.

There were absolutely loads of Wheatears on Portland, including this rather lovely male. They will have overwintered south of the Sahara and have migrated through Spain, before reaching France and crossing the channel. Some will stop off and breed while others will just pass through on their way northwards to Iceland, Greenland and Canada. 

I saw quite a few Redstarts during my stay, but they were all very distant! Another summer migrant, this male will have wintered directly south of the Sahara and could have either come through Spain or Italy before it reached the English Channel. 

Another 6am start in the obs garden, I heard a distinctive bird song coming from the apple tree close by. After a quick scan with my binoculars, I saw the creator of this song - a male Cirl Bunting. 

While most Cirl Buntings are sedentary, very small numbers do migrate. This one will have probably come from continental Europe and will breed somewhere on Britain's south coast.

This is only the second time I've seen Cirl Bunting - my first ever sighting was in Devon, as a previous blog post mentioned:

 https://natureandwildlifeimagesuk.blogspot.com/2023/01/devon-birds.html

It was around 5pm when I decided to go for a stroll up into the Top Fields to see if anything was about, when I noticed a flock of around 20 Goldfinch drop into an area of bramble scrub a little way off. I scanned the flock and saw a Serin in with them. I quickly put the news out on Twitter and within minutes a few other people had joined me, watching this beautiful bird. Soon after, I spotted a male too, who was also flitting around in the bramble patch. 

The next morning, in the obs garden again, a male Serin (presumably the same one from the previous evening) briefly dropped into the large apple tree.

Serin are quite an uncommon bird in Britain, with around 60 birds recorded each year, though there's no way of telling exactly where they have come from; it's most likely that they are overshoots from their migration from Spain into France and have gone a bit too far.

Another evening, I walked up to the Top Fields and was pleased to see a beautiful Short-eared Owl glide through over the fields, before it drifted out of sight.

It is most likely a bird from the continent, visiting Britain to breed, before heading back south to spend the winter. 

Of course, its not just migrants which can be found on the isle; there are a couple of quarries near the Bill which hold breeding Little Owl.

One of my favourite places to visit was the West Cliffs, where I stood and watched birds migrating, like these Goldfinch which were often moving through, in large flocks, on their way from the continent to breed in Britain. 

Another species I saw whilst doing 'vismig' (visible migration watching) was Meadow Pipit, coming in off the sea from their wintering grounds in Iberia. 

Other species seen on my vismig counts included large numbers of Linnet, Swallow, House Martin and Sand Martin and smaller numbers of Wheatear, Pied Wagtail, Yellow Wagtail and Common Whitethroat.

There was lots to watch on the sea as well; Gannets were quite often seen, sometimes in small groups, like these ones.

Common Scoter was another regular sight, and were often seen passing the shore, sometimes quite close. 

Whilst I stood on the cliffs, Fulmars regularly flew below me, giving very close views. 

Another species which was often seen passing the coast was Whimbrel, usually in small groups like this one. Can you spot the single Bar-tailed Godwit in this flock? (check for an upturned bill!)

Another great place for birding is Ferrybridge, situated next to Chesil Beach, the strip of land separating Portland from the 'mainland'. Its main attraction are Little Terns, which nest on the Chesil every year. 

They are our smallest breeding tern, and are very vulnerable to disturbance and predation; volunteers from the RSPB monitor the terns while they are nesting, and protect the nesting sites with electric fences. 

To avoid disturbance, I watched them from a safe distance and out of their nesting areas. 

Another species of tern which can be seen here is the Sandwich Tern, a larger and commoner species than Little. I counted around 10, flying around the area, diving into the water and coming out with a small fish.

I had a great week birding at Portland, it was a fantastic experience.