Officers arrived at Canaport LNG just before 9 a.m. on Thursday.
Inside the facility’s security building, men in Environment Canada uniforms monitored people coming and going.
"Environment Canada wildlife officers are investigating a kill of migratory birds that occurred early in September. Today the officers are executing a search warrant trying to gather additional evidence as part of that investigation," said Craig Smith, speaking for Environment Canada.
It’s unclear what was seized.
In mid-September, about 7,500 migrating birds were killed when they flew into the gas flare at Canaport LNG.
Don McAlpine, the head of zoology at the New Brunswick Museum, said they were drawn like moths to a light. The weather conditions were foggy and overcast at the time, which may have contributed to the incident, he said.
Not much is known about how such birds navigate at night, but it is believed they are attracted to light, particularly red or flashing lights, said McAlpine.
McAlpine is still examining several hundred of the dead birds, which are being stored in a freezer, to try to identify their species.
There were a large number of red-eyed vireos, several types of warblers, including parula, black-and-white, magnolias and redstarts, as well as a few thrushes and rose-breasted grosbeaks, he said.
It's possible there may have also been some endangered species, such as the olive-sided flycatcher and Canada warbler, which are on the federal government's species at risk registry, said McAlpine following the incident.
Many of the birds were badly burned, but some appeared completely unscathed, said McAlpine. He suspects they became disoriented and hit the tower or the ground.
Kate Shannon, spokeswoman for Canaport LNG, said the flare is now turned off thanks to continuing upgrades and that the company is fully co-operating with investigators.
"We're confident that any information they obtain today will show evidence that we've been honest and transparent through this whole thing," she said.
Naturalist group pleased to see action
In an open letter published on Tuesday, Nature New Brunswick urged regulators to pursue this investigation.
"Nature New Brunswick has been concerned right from Day 1,” said Jim Wilson, a birder and naturalist speaking for the group.
"They have a duty to be doing this, and you know they have a fair amount of clout when it comes to investigations, so yeah, I'm pleased that they are at least looking at this seriously," said Wilson
Environment Canada is responsible for both the Species at Risk Act and the Migratory Bird Act.
So far, no charges have been laid against Canaport LNG. That decision will come once officers have had a chance to sort through all the evidence seized.
Meanwhile, the company hopes that by shutting down the flare, it can avoid future bird kills.
The flare tower at the Canaport liquefied natural gas receiving and regasification terminal is about 30 metres tall and the size of the flame would vary, depending on weather conditions.
Flaring has been part of the standard operation at the east-side plant, located on Red Head Road, and is designed as a safety release system. It is used to maintain normal operating pressure by burning off small amounts of excess natural gas.Suggest a correction