Starling Roost Behaviour: What We Found by Accident in Northumberland

This one wasn't planned. While travelling north through Northumberland on the way up to Scotland, we spotted power lines absolutely covered in starlings, and it turned out we'd stumbled onto a roost entirely by chance. The giveaway wasn't the birds themselves, it was the smell. A row of bushes nearby turned out to be thickly 

covered in droppings, a sure sign this same spot was being used to roost night after night.

That gave us a few hours to set up before dusk and try filming a starling roost forming with thermal and infrared cameras, including the Whisker, for the first time. You can watch the full episode here, this piece covers what the footage actually shows once you know what you're looking at.

Why didn't they murmurate?

European starlings are famous for murmurations, those huge, swirling clouds of thousands of birds that pulse and twist together right before roosting. The mechanism behind it is genuinely remarkable: each starling tracks and matches the direction and speed of roughly its seven nearest neighbours, not the whole flock, which is enough to let a movement ripple through thousands of birds almost instantly with no leader and no signal, useful for confusing predators and for huddling together for warmth once they do settle.

Here's the honest part: on the evening we filmed, that classic swirling cloud never really happened. Starlings arrived in smaller waves instead, groups of ten or twenty at first, then flocks of two or three hundred at a time, until well over a thousand had passed overhead and more than 5,000 birds had gathered in total. Murmurations are a genuine, well-documented behaviour, but they're not guaranteed just because the numbers are there, which is worth knowing if you're hoping to catch one yourself.

Chaos in the roost, then dominance sorts it out

Once the starlings were down among the trees, the roost itself was pure chaos to begin with, birds flying in and out, jostling for position with no obvious order. That settles faster than it looks. Research on starling roosts backs up what the footage showed: older, dominant birds tend to claim the safer, more central positions, while younger or subordinate birds get pushed toward the edges, where visibility and warmth are both worse.

Whether the edge birds also sleep differently to cope with that risk is genuinely debated. Many roosting bird species are known to use unihemispheric sleep, resting one half of the brain at a time with one eye open, to stay alert for predators while still getting some rest, and it's often assumed starlings do the same. Some sources suggest they don't rely on this mechanism as heavily as species like ducks, and instead depend more on balance and reflexes to stay safely perched while dozing. We'd rather flag that uncertainty than present it as settled.

Quiet at last

Once positions were sorted, the roost properly settled and everything went quiet for the night, right up until the same chaos would begin again the following morning as the birds dispersed to feed. Switching to thermal imaging once it was fully dark showed the scale of it properly, hundreds of small heat signatures tucked into the vegetation, most of them barely visible otherwise.

The kit behind the footage

This episode was filmed using the Nightfox Nova, the Thermal Master DV2, and the Whisker, to cover both the pre-roost gathering in daylight and the settling roost after dark without needing any additional light. If you want the fuller detail on how bat roosts are surveyed and protected, a closely related but legally distinct topic, our piece on bat survey season covers that ground. For badgers, our badger sett behaviour piece is the direct companion to this one from the same series.

Next in the series: Dan heads to a small island off Scotland's west coast to follow otters after dark.

FAQs

Why do starlings form murmurations? The leading explanations are predator confusion (a shifting, dense flock is harder for a bird of prey to target) and warmth, since huddling together before roosting helps starlings conserve heat overnight.

How do starlings avoid colliding in a murmuration? Each bird tracks and matches the movement of roughly its seven nearest neighbours rather than the whole flock, a rule discovered by researchers filming and reconstructing murmurations in 3D. That simple, local rule is enough to let coordinated movement ripple through thousands of birds at once.

Do starlings always form murmurations before roosting? No. Large numbers of starlings can gather and roost without ever forming the dramatic swirling display most people associate with the word, timing, predator presence, and weather all seem to play a part.

Where do starlings get the safest spots in a roost? Older, dominant birds tend to claim the more central, sheltered positions, while younger or subordinate birds are typically pushed toward the edges of the roost.