Pear tree pest

Noticed today that a couple of the pear trees where I was working have had their leaves attacked. Lots of holes, a few leaves curled up with gossamer but no culprit in sight. Is there a particular pest of pear trees?

Chris

 

If you can see evidence of cocoon building material it is likely to be caterpillars, although aphids can also cause leaf curl.
There was story on the news yesterday about an infestation of caterpillars on some cherry trees in Bradford ~ BBC News - Ermine moth larvae infest Bradford park ~ that will make your toes curl.