The High Line, one of New York's newest tourist attractions, may have brought a different kind of visitor: a cockroach that can  withstand harsh winter cold and never seen before in the U.S.

  Rutgers University insect biologists Jessica Ware and Dominic  Evangelista said the species Periplaneta japonica is well  documented in Asia but was never confirmed in the United States  until now. The scientists, whose findings were published in the  Journal of Economic Entomology, say that it is too soon to  predict the impact but that there is probably little cause for  concern.

  "Because this species is very similar to cockroach species that  already exist in the urban environment," Evangelista said, "they  likely will compete with each other for space and for food."

That competition, Ware said, will likely keep the population low,  "because more time and energy spent competing means less time and  energy to devote to reproduction."

  Michael Scharf, a professor of urban entomology at Purdue  University, said the discovery is something to monitor.

  "To be truly invasive, a species has to move in and take over and  out-compete a native species," he said. "There's no evidence of  that, but that doesn't mean we shouldn't be concerned about it."