Rising waters pose peril to falcon family
As the flood waters of two weeks ago were immersing many parts of Carlton County, a tense little drama was playing itself out in the St. Louis River wall, just downstream from Sappi's Cloquet mill.
A pair of peregrine falcons who have nested in that area for the past two or three years had produced a rare family of five chicks (four is the norm). On that fateful Wednesday following the torrential downpours, the river was rising at an alarming rate. The mill itself was evacuated of all but essential staff, which remained to try to erect makeshift dikes to protect the buildings. And though safeguarding the mill was the primary concern of employee Mary Krohn, never far from her thoughts were the helpless chicks that were at the mercy of the rising waters.
According to Krohn, the falcon nest in the river wall had already been targeted as a less-than-desirable site for the birds to nest.
"One of our steam plant chief operators, Jay Zack, approached me last year when the birds were being very defensive of their nest area," reported Krohn, "and asked if Sappi would consider trying to attract them to a nesting spot a little further from where our employees need to be moving around."
It seems that once the birds had their young they tended to "dive bomb" anyone walking in the area, though Zack pointed out that they are also very good pigeon control, since peregrine falcons prey on other birds.
Krohn contacted the local office of the Department of Natural Resources, who in turn put her in touch with Jackie Fallon, field coordinator for a non-profit organization known as the Midwest Peregrine Society, an offshoot of the University of Minnesota's Raptor Center. Fallon and others from their group travelled to Sappi's Cloquet mill last November, looked at the nest and gave suggestions for nesting box design and location, with an eye toward luring the birds to a more appropriate and less trafficked area.
Over the winter, mill employee Scott Johnson volunteered to participate in building and installing a nesting box high on the east side of the mill's tall recovery boiler.
"The birds tend to like being high, near the river and near a good food supply," said Krohn. "They are not disturbed by any of the normal manufacturing activity in the area, aside from discouraging people from coming too near their nest."
Fallon said one of the adult falcons is thought to have remained in the area all winter, possibly due to the plentiful food supply, though normally the birds don't return to their nesting site until early March. The female of the pair is unbanded, which Fallon said indicates she most likely was fledged on the North Shore, since there are a number of nesting sites in that area that cannot be accessed and the birds raised there have never been banded. The male, it was discovered, was banded in 2008 and is from Square Top Mountain, Ontario.
Early this spring, the falcon pair was spied sitting on the roost of the new nesting box, but in the end they opted to nest once again in their old home in the river wall.
"Since they've gone to that site in the past and been successful," speculated Fallon, "they are probably reluctant to leave it."
Volunteers from the Peregrine Society began monitoring the birds in mid-February, coming out periodically to observe them.
"They kept us apprised of when to expect eggs and when they might hatch," said Krohn.
On May 22, volunteers from the Peregrine Society once again visited the mill and Scott Luedtke from Sappi's Process Engineering group used a boroscope (a long tube with a camera on the end) to peer into the nest area.
"They were able to see a little ball of fluff that looked like three or maybe four golf-ball-sized chicks," reported Krohn.
The volunteers returned on June 7 to band the chicks and were pleasantly surprised to find five good-sized, well-fed chicks in the nest.
"In the 25 years I've been working with the Peregrine Society," said Fallon, "I've only seen three broods of five falcons." She speculated that plentiful access to food and mild spring weather are both assets to falcon productivity and added that the fact that both adults are young possibly contributed to the large brood as well.
To band the chicks, one of the specially trained volunteers from the Peregrine Society team used a rock climber's rope and harness to rappel down to the nest, retrieve the young birds and place them in a special compartmentalized box. Since the box had only four compartments, however, they used a backpack to transport the fifth chick. Amidst a near-deafening din of excited complaints from the young birds, they were taken to a conference room in the mill so research volunteers could determine if they were male or female, which they do by measuring the size of their feet.
"The females' feet are larger," explained Fallon, "since they are the ones who sit the nest and need the power to be more protective in the face of predators."
It turned out that three of the chicks were females and two were males.
After the chicks were sexed, a small blood sample was taken so researchers can use DNA to trace the ancestry of the birds. Then two bands were applied to the leg of each chick - one of them which is federally required and the other, called a "project band," bears identifying letters and numbers on it that are large enough to be read through a spotting scope so researchers can determine whatever background information has been logged on them. Bands allow researchers to see where the chicks go after they hatch, where they set up their territories and whether or not they survive.
OPTIONAL TRIM IF NECESSARY: In all, Fallon said the banding procedure lasted about half an hour from start to finish, from the time the men began the descent to the nest to the time the chicks were returned to it.
"We don't want to stress the adults out," said Fallon.
She said from the time the car bearing the researchers was first parked in the vicinity of the nest, the adult birds started dive bombing them.
"They have made a big investment in those babies over the past two months," said Fallon, "and as far as they knew, some sort of giant predator was about to take them away."
Though the birds never actually made contact with any of the field team, Fallon said the volunteers wore hard hats and goggles to make certain they were safe.
"The adult birds fly at people to make them leave," she explained. "The longer you sit there, the more aggressive they're likely to become. Though we've never had a bird or person injured, the faster we can get in and out of there the better."
She said if there is any risk to the birds in the banding procedure, it isn't done at all. She said she was part of a team that was called to survey a nest on a bridge over the Mississippi River earlier this week and they determined not to go in and band the chicks because it was feared they were too close to the edge of the bridge and might fall in the river if startled.
As soon as the chicks were returned to the nesting site near Sappi, the adults flew in to check on their welfare.
Now that the falcon chicks are older and require a lot of food, the parent birds have been staying very close to the nest.
OPTIONAL TRIM IF NECESSARY: Fallon said there are currently some 6,300 falcons that have been banded in the state of Minnesota, though DDT practically wiped out the population of peregrine falcons in the United States in the 1950s and 1960s. Though the birds are yet apt to be exposed to the toxic chemical in some parts of the country, it has largely ceased to be a problem in the Midwest.
The local falcons are now part of an on-going research project that covers 13 states as well as Manitoba and Ontario that has been going on for the past 30 years and was started by the Raptor Center of the University of Minnesota.
Fallon said though falcons have been taken off the federal Endangered Species List, the state of Minnesota continues to list them as a threatened species. There are currently 60 nesting pairs of peregrine falcons in the state and 300 in the entire country.
"The species is definitely recovering," said Fallon.
She said each nesting pair is monitored once every three years so the species doesn't get into trouble again.
"This is a really unique conservation effort," she said. "To go from zero to full recovery is fantastic, especially when more and more humans are competing for the same territory as the birds are."
She said the entire effort of the non-profit Midwest Peregine Society has been supported and conducted by private individuals who want to save the falcons.
"It took 25 years to go from full protection to full recovery, and we are very, very proud of that," she said. "Hundreds of people in Minnesota have been a part of this effort, including private property owners, industry, and the DNR."
"The story of the peregrine falcon recovery is a very good story and we take a lot of pride in it," she said. "We couldn't do it without the help of people like the ones at Sappi who are so accommodating, easy to work with and feel the birds are of value. It's a great partnership."
The young birds in the nest at Sappi were within just days of being able to fly when the flood struck, a time which Fallon said is an important point in their survival. She explained that when the inexperienced chicks leave the edge of the nest they have to either fly or risk falling into to the river.
"It' a little like handing the keys to a Ferrari to a 15-year-old kid who has never driven before and telling him to get it up to 150 miles per hour," she said.
If they successfully leave the nest, she said they will go on to learn to hunt and fend for themselves until next October or so, when they will go off on their own to establish new territories.
"It is fantastic to see these birds making a comeback and we are delighted to be hosting this Peregrine family on our Sappi mill site," commented Krohn prior to the flood.
But on that Wednesday morning, no one could help the little falcon family, since it was too dangerous to make the effort to get to them and all were tied up with survival efforts of their own. Their fate remained unknown until the flood had subsided and the work of Sappi's personnel in getting the mill up and running once again was well under way.
Last Monday morning, Krohn filed her first report on the birds.
"We believe at least a couple survived," she said. "On the day after the flood we used a boroscope to peer into the nest and saw only one lone chick. But we believe we are seeing a couple of fledglings exercising their wings around the area. Jackie [Fallon] is going to come out on Wednesday to spend some observation time and see if she can read the bands on the fledglings we believe we are seeing and try to see how many we might have."
And then on Wednesday, the good news got better.
"Jackie Fallon from the Peregrine Society was here this morning ," said Krohn, "and she saw four of the chicks perched next to the father bird!"
Information on all banded falcons will soon be available to anyone who wishes to access it at midwestperegrine.org.
"By August or September, people will be able to type in 'Cloquet' and find out about the status of the chicks born there this year," explained Fallon.