The Spurn Effect

The Spurn Effect. If you haven’t heard of it, it’s a phenomenon whereby a twitchable rarity is quickly followed up by the finding of one or more rarities at the same site. Such as the recent county-first Rustic Bunting at Ham Wall, Somerset, seen by birders visiting for the River Warbler. There are possibly many reasons for it, but it’s usually attributed to lots more visiting birders on site to see the initial rarity - more eyes mean more birds are likely to be found. It’s called the Spurn effect because the high concentration of birders in such a small area is bound to turn up great birds.

But what else might be causing The Spurn Effect and what does this mean for our birding? 
Well one answer might be that the favourable weather system which brought the initial rarity was responsible for bringing the other(s). In other words, this really was an isolated incident and the site is undergoing a purple patch due to good conditions. 

But what about when the birds clearly have different origins as is so often the case? Take for example the recent Bonaparte’s Gull at Rutland Water quickly followed by a Kentish Plover. Other examples include a Subalpine Warbler found the day after the Sulphur Bellied Warbler on Lundy. On a smaller scale an inland rarity almost always seems to lead to the finding of great local birds. For example, Sandwich Tern and Wood Sandpiper being found during the stay of the recent Blyth’s Reed Warbler at Middleton Lakes, but then followed by no Birdguides reports at the site for the following 10 days after the departure of the rarity.

The stay of the Blyth's Reed Warbler at Middleton Lakes saw several other interesting local birds being found

Ultimately, this surely implies that the Spurn Effect is mostly down to more people looking and not simply good conditions. In which case, rare birds must always be out there to be found. Unless by some extreme coincidence two or more isolated rarities always happen to randomly occur on the same day on different weather systems, we can only conclude there really are so many rarities which are going unnoticed! And if that doesn’t inspire you to go out and check your local patch I’m not sure what will!
Sometimes admittedly the odds are stacked against you, and if you’re patching an inland site in mid July you’d be excused for having very little hope in your heart. After all, no one has found anything else rare at Bempton and Flamborough during June and July despite it being coastal and thousands of visiting birders being present for the Albatross.

But just knowing that a Rustic Bunting might have been hiding for days in the height of summer under the noses of the thousands of us that went to see the River Warbler ought to provide us with some renewed motivation that rare birds really are everywhere. And isn’t that half the battle won?

The psychology of birding really isn’t something that’s discussed all that often. But it’s huge. Yes, the influx of birders is mostly responsible for the Spurn Effect but I’d argue that mentality has a huge part to play too. If you’re at Frampton Marsh seeing a Semipalmated Sandpiper after a great westerly airflow, you’re going to check every last Dunlin because the belief is there that you might find something else. 
Another illustration is the Rose-coloured Starling influx. I will own up and say that the only reason I scanned through the Starling flock on the Isle of Iona is because I knew about the influx. In fact I’d just said the words “we better check these starlings just in case” - sure enough, there one was. The very act of believing it was there brought it to fruition. And it wasn't manifestation or magic it was simply a case of having enough optimism to look. I wouldn't have scanned the Starlings otherwise. 

A Rose-coloured Starling I found on Iona - one of my first self-found rarities

How many times have you twitched a bird and not seen it on several initial scans, but kept going because you know it’s there, and eventually seen it? Had you not known or believed it was there, you might never have seen it.

And so I’m going to make it my mission to approach birding this autumn as though the birds are there, it’s just my job to find them. As though anything is possible. Because if the Spurn Effect tells us anything, it’s that they are. It just might take a large influx of visiting birders to find them. It’s not going to mean I find a Siberian Rubythroat in Leicestershire, but maybe it’ll give me the drive to scan through yet another tit flock to pick out a Yellow-browed Warbler. 

There have been many occasions I’ve been trudging back from a bleak winter walk on patch, head down looking at the path in front of me. Now, I’m not saying I walked straight past a Little Bunting, but if one was wintering in the farmland then I would have walked straight past unaware!

I wouldn’t be looking at the ground if I was at Spurn. The Spurn Effect might be so-named because the high concentration of birders in such a small area is bound to turn up great birds. But maybe it should be called the Spurn Effect for another reason also - because for me, twitching and seeing a rarity has a Spurn Effect on my optimism, it gives you the Spurn mentality - the feeling that the next bird you see might be just as rare. 

So this autumn, if I see an unusual Sylvia warbler fly into a tree maybe I'll stop myself to get another view. I won't just tell myself I'm in the midlands and it's nothing. Yes, the overwhelming probability is that it will be a Blackcap, but if I don't look how can I expect to find anything unusual! I’m going to use it as an experiment to see whether this is real, by imagining my walk through inland Leicestershire is a stroll along the Spurn peninsula, by honestly believing that there are rarities out there waiting to be found. 
Could it really help me to find more birds? I suppose there's only one way to find out.