After taking a dip last year, bike thefts are back on the rise, according to Vancouver police.

Between January 1 and May 31 of this year, 554 bikes were reported stolen.

That's up from the 338 thefts reported during the first six months of 2011.

For the same period in 2010, 490 bikes were reported stolen. That figure was 439 for 2009 and 381 for 2008.

Police say the southwest portion of the city and the downtown core are being targeted the most.

"Thieves are not being deterred easily," Const. Brian Montague said in a statement today (June 15). "We have had reports of thieves scaling apartment balconies to steal bikes, throwing them down to the ground before riding off. However, the overwhelming majority of thefts are from bike racks and other public places."

Police advise bike owners to record serial numbers, use a sturdy lock, and make note of modifications in order make identification easier should a bike be stolen and then recovered by the cops.

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