Look at those figures:
|Simon Wright||Liberal Democrat||13,960||29.4||-0.6|
|Steve Emmens||UK Independence Party||1,145||2.4||+0.9|
|Leonard Heather||British National Party||697||1.5||+1.5|
|Gabriel Polley||Workers Revolutionary Party||102||0.2||+0.0|
Yes, the Lib Dems actually gained a seat while losing share. What happened was that Labour lost many more (with an appreciable number going Green), letting the LDs in.
(East England is pretty solid blue. Tories: 52. LDs: 4. Labour: 2 (the two Luton seats, with control freak Esther Rantzen failing).