Labor unions in Massachusetts added nearly 80,000 members last year and significantly increased the share of workers they represent, according to the Bureau of Labor Statistics. Union membership grew to 458,000, or about 15.7 percent of workers in 2008, up from 379,000, or about 13.2 percent, in 2007. Nationally, union membership rose to 12.4 percent of workers from 12. 1 percent in 2007.

"As the economy implodes, workers are increasingly looking for the protection and security provided by unions through collective bargaining," said Richard M. Rogers, executive secretary-treasurer of Greater Boston Labor Council.

Massachusetts is one of 20 states with higher union membership rates than the US average. In New England, Connecticut had the highest membership rate, 16.9 percent of workers, up from 15.6 percent in 2007, followed by Rhode Island, with 16.5 percent, up from 15 percent.

Union membership in Maine rose to 12.3 percent from 11.7. In New Hampshire, it increased to 10.6 percent from 9.7 percent, and in Vermont, it remained unchanged at 10.4 percent of workers.