Officials concerned about Asian carp invading Lake Michigan tributaries are breathing a sigh of relief this week, after no new evidence of invasion was uncovered. Experts are now saying that initial DNA evidence discovered earlier this month was likely just a false alarm.

Officials with the Michigan Department of Natural Resources (MDNR) and the US Fish and Wildlife Service (FWS) initially found evidence of Asian carp DNA in Kalamazoo River - which runs into Lake Michigan - back on Oct. 2. However, this was in one sample out of 200, indicating either the very slow beginnings of an invasion or simple contamination from a boat, fishing gear, or even bird droppings.

The FWS estimates the net worth of the Great Lakes fishery is about $7 billion. That and other economic interests dependent on the Great Lakes and their tributaries have prompted a strong political desire to protect these waters from encroaching invasion, with joint field exercises and regular DNA sampling being performed in a proactive effort. Follow-up DNA sampling was even taken to either confirm or quell Kalamazoo suspicion.

Now the results of that DNA analysis is back, and it looks like we're in the clear. Ed Golder, a spokesperson for the MDNR told local reporters Monday that none of the 200 environmental samples from Kalamazoo river came back positive for Asian carp DNA. If bighead carp or silver carp were in the river, it's extremely unlikely that their presence would have been overlooked.

Still, "we're not letting our guard down by any stretch of the imagination. We're still doing a lot of outreach and education with anglers and boaters in the Kalamazoo River," Tammy Newcomb, a DNR senior water policy advisor, told Fox 17.

An additional positive result for silver carp DNA was identified in Fox River just last week - also a one in 200 result. FWS officials are still waiting for that river's follow-up testing.

Invasive Asian carps like bighead and silver carps infamously consume large amounts of plankton - a crucial source for native fish and other aquatic life. Scientists fear that the spread of Asian carp in the United States - where they have few predators - will cause irreparable harm to the Great Lakes' food web.