Small-cap stocks bounced in and out of positive territory Thursday, slightly trailing the broader market as earnings reports once again motivated the major buying and selling. Shares of Gibraltar Industries ( ROCK), which makes residential and commercial building products, soared 28% to $14.12. The Buffalo, N.Y., firm posted first-quarter earnings of $6.7 million, or 22 cents a share, vs. $6.2 million, or 21 cents a share, a year ago. Analysts surveyed by Thomson Reuters were expecting 14 cents a share. Meanwhile, Central Garden & Pet ( CENT) jumped 29% to $5.40. The Walnut Creek, Calif.-based purveyor of branded products for the lawn and garden and pet supplies markets announced income of $20.5 million, or 28 cents a share, vs. $21.4 million, or 30 cents a share, a year ago. The Street was looking for 25 cents a share. Niwot, Colo.'s Crocs ( CROX), a footwear concern, added 17% to $11.60. The company reported non-GAAP first-quarter earnings of $7.6 million, or 9 cents a share, slightly behind the consensus estimate of 10 cents a share. Crocs also reaffirmed full-year guidance for EPS between $1.70 and $1.80, ahead of the Street's prediction of $1.60. Einstein Noah ( BAGL), which licenses specialty bagel restaurants, saw shares climb 17% to $12.86. The Lakewood, Colo., company said it made $3.8 million, or 23 cents a share, for the first quarter, vs. $1.1 million, or 10 cents a share, in the year-ago period. Analysts had foretold earnings of 16 cents a share. Piper Jaffray added to the good news by upgrading the stock to buy from neutral.