The Maine Department of Inland Fisheries and Wildlife hopes a new survey will tell state biologists how far north invasive Northern pike are in the Penobscot River.
The survey, expected to begin possibly as soon as next week, will include trapnetting and tagging up to 500 pike in the inlet and outlet of Pushaw Lake, according to Enfield region assistant regional biologist Kevin Gallant.
Pike pose a threat to native species of fish such as brook trout and landlocked salmon because they can quickly eat up the food supply. Pike are firmly established in Southern Maine, especially the Belgrade Lakes area, but are slowly making their way north.
“I’ve seen one up to 18 pounds in Pushaw,” Gallant said on Friday.
The idea is for fishermen who catch the tagged pike to go online and fill in the requested information about the fish, including where it was caught. Fishermen may keep or release their catch after recording the information from the tag.
Biologists expect the tagged fish to be caught in Pushaw Lake, Little Pushaw Pond, Perch (also known as Mud) Pond, Stillwater River and Penobscot River.
Pike are clearly established in the lower Penobscot River already, and there have been fishermen reports of a couple in West Enfield below the dam and a nearly 8-pound one near Cold Stream, Gallant said.
Biologists netted and removed pike from Pushaw for 15 years in a row, but realized it was a losing battle. Pikes haven’t been netted there in eight years, he said.
“Pike in Pushaw itself isn’t as big a deal, but once in the Penobscot, they can get in other places where there are native fish,” he said.
The attitude of fishermen in the early 2000s was to get the pike out of the lake, but now they want to fish for them, Gallant said.
Pike like streams, flooded marshy areas that are weedy and murky with shallow water, which is where their monthlong spawn occurs. They can begin reproducing at a year old, just weighing a couple pounds and at about 16 inches long. Pikes can produce 9,000 eggs per pound of body weight, he said.
The trapnetting and tagging will begin as soon as the ice goes out, which may be next week but definitely the week after, Gallant said. There will be signs posted at landings and boat launches at the lakes and ponds involved, plus a few at outlying ponds and upriver in case the fish venture that far.
The survey will be paid for through the department’s invasive species funding.