A University of Colorado at Boulder professor involved with the Cassini-Huygens mission is reporting an ever-changing vista at the frontiers of Saturn, featuring wayward moons, colliding meteoroids, rippling rings and flickering auroras.

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A UVIS analysis of Phoebe -- a tiny, dark moon about one-fifteenth the diameter of Earth's moon -- confirms the suspicions of many space scientists that it was born elsewhere, likely in the Kuiper Belt. The Kuiper Belt is a region beyond Neptune believed to populated with thousands of small, icy moons created during the formation of the solar system more than four billion years ago.
"UVIS sees the absorption signature of water ice on its surface, showing Phoebe was born in the outer solar system," Esposito said. Exhibiting an unusual retrograde, or backward, orbit, Phoebe likely was lassoed by Saturn's powerful gravitational field during the planet's formative years, he said.

From Spaceflight Now article.

I suspect many of the 30 plus moons of Saturn turn out to be captures.