In this clip from Iolo's Welsh Safari, the team visit Aberystwyth Pier to watch an amazing natural spectacle unfold as 1000's of starlings descend on the pier at dusk - up to 20,000 birds in some instances.
No-one knows for sure why they do this but it might be for safety in numbers, as protection from predators such as peregrine falcons and sparrowhawks.
Another theory is that it's a sociable act, as the birds sort themselves out into individual groups before landing for the night.
Once one of the country's most common birds, the starling has suffered a 70% drop in its numbers over the last 25 years.
It is known primarily for two things: the spectacular 'murmurations' of thousands of birds wheeling before the roost at dusk, and their ability to mimic the calls of other birds and mechanical noises.
Its plumage, although black from a distance is actually iridescent with a green-purple sheen to its wings and back. It is smaller than a blackbird, with a short pointed tail and triangular wings.
The starling feeds on scraps, seeds and from feeders but will also probe into lawns for worms and grubs.
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