Lessons from Isle Royale's Wolves and Moose

TRAVERSE CITY, Mich. - Several U.S. senators want the federal government to decide faster what to do about Isle Royale National Park's imperiled wolf population.

Scientists say only three gray wolves remain on the Lake Superior island chain. Their numbers have plummeted in recent years, probably because of illness and inbreeding complications. 

The ongoing study of wolves and moose on Isle Royale in Lake Superior has hit a critical juncture. Researchers in charge of the longest continuous study of a predator-prey system anywhere in the world released their annual report today. 

You can read the full report here.

A wolf that fled from Isle Royale National Park over an ice bridge was found dead on the Minnesota mainland last month.

Researchers were unsure how the wolf died at the time, but a necropsy found that the five-year-old female wolf was shot with a pellet gun.

Lee Berquist of the Milwaukee Journal-Sentinel has more:

The last time I checked, the ice bridge to Isle Royale had not fully formed, but there's an ice bridge now.

Michigan Technological University's Rolf Peterson confirmed it in an e-mail to me last night.

"There's been a good ice bridge for the past 10 days."

Update: Friday, February 7, 2014

The ice bridge to Isle Royale has formed. See our post here.

Original post: January 9, 2014

Wolves first came to Isle Royale in Lake Superior by crossing an ice bridge in the late 1940s, but these ice bridges have not been forming as often in recent years and the wolf population on Isle Royale has been suffering as a result.

ISLE ROYALE, Mich. (AP) - Isle Royale National Park's gray wolves apparently don't have a gender gap after all.

Scientists reported last year that only nine wolves remained on the Lake Superior island chain - the lowest total in more than 50 years. They said just one was known to be a female, raising doubts about the predator's long-term prospects for survival in the wilderness park.

But Superintendent Phyllis Green said Thursday that genetic analysis of wolf excrement and additional observations suggest that four or five of the animals are females.

Even so, Green says the wolves' situation remains tenuous and experts are studying how climate change may affect them.

Michigan Technological University biologists are conducting their annual winter study at Isle Royale and are expected to release updated wolf and moose numbers next month.

In the last year, seven wolves on Isle Royale died. The total population is now down to nine wolves.

That's the lowest number recorded by researchers who have been studying the Isle Royale wolf population for the last 54 years. It's the longest continuous predator-prey study in the world.

When Rebecca Williams and I visited Rolf Peterson on Isle Royale last month, we asked him about the die-off.

He told us they didn't know what happened to them, "but we will know," he said.

Well, now they know how three of the seven wolves died. One was a young female wolf.

We've been posting radio pieces, videos, and blog posts all week as part of our series Lessons from Isle Royale's Wolves and Moose.

Researchers like Durwood Allen, and Michigan Tech's John Vucetich and Rolf Peterson have been keeping a close eye on the animals on the island for more than five decades.

Peterson has been doing it the longest. He's been watching and documenting things on Isle Royale for 42 years.

Wolves and moose are at the heart of the world’s longest running study of a predator and its prey.  The drama unfolds on Isle Royale National Park in Lake Superior.

But it’s a big island, almost entirely wilderness.

The researchers from Michigan Tech say they can’t cover all that ground alone. 

So they have a program called Moosewatch.  It’s a backcountry expedition where you pay to help out with the wolf-moose study.  But be warned: it’s no easy little walk in the woods.

"We’re going to trash through the understory here for a third to half of a mile and see if we can find some dead moose."

That’s Jeff Holden. He’s a Moosewatch group leader, in charge of a group of six (himself plus five volunteers).  We’re going to push our way into the thick forest.

The longest running predator-prey study anywhere in the world takes place right here in Michigan.

For more than five decades, researchers have been closely watching the ebb and flow of wolves and moose on Isle Royale.

To do their work, wolf biologists Rolf Peterson and John Vucetich of Michigan Tech lean on those willing to pitch in and help.

Moosewatch volunteers hike off-trail for miles with their backpacks getting heavier as they pick up moose bones along the way.

They get bitten by bugs, scratched by branches, and soaked by the rain as they make their way through Isle Royale's boreal forest.

And they pay for the experience. It costs $450 per person, which covers the expenses for the wolf-moose project.

The researchers have been relying on these summer volunteers since 1988. John Vucetich says overall, about a third of all bones they collect are collected by Moosewatch volunteers.

"In a typical year they find the skeletal remains of 50 to 75 moose.  They perform necropsies on these moose and collect several specimens (skull, jaw bone, metatarsus, and any arthritic bones)," says Vucetich.

Rebecca Williams and I recently went out with a Moosewatch group on Isle Royale.

Each group is made up of six people. Five volunteers and one group leader.

The leader is in charge of making sure people don't get separated and lost in the dense forest.

Our group leader, Jeff Holden, described himself as a bit of a mother hen, which is a good quality to have for someone looking after five people for an entire week in the backcountry.

Holden's job was made especially hard when we arrived. He now had two reporters to keep track of as well.

I tended to wander off a little with my camera as I tried to anticipate where the volunteers would come out of the woods:

I never wandered too far, and I captured some video of these volunteers at work in the woods.

Here's what the Moosewatch experience is like:

Moosewatch volunteer David Conrad says his friends don't know what to think of his trip to Isle Royale.

"They can't find this place on a map," says Conrad. "They think the U.P. is part of Canada. [I tell them] 'yeah, I'm going to an island in Lake Superior to count dead moose, and maybe see a live one.' People think I'm crazy. It's just a cool little adventure."

When you camp on Isle Royale, you don't necessarily have to sleep in tents.

You can sleep in a "camping shelter," which is basically an elevated, screened-in, wooden structure.

It can protect you from the elements and the bugs.

And based on our experience, it seems people have had some time on their hands waiting out storms in these shelters.

Park visitors have left messages on the walls - something we humans love to do - even long before we had Facebook walls to write on.

It's not as gross as it sounds. And if you heard yesterday's report from Rebecca Williams, it really does sound gross.

The wolf-moose research project on Michigan's Isle Royale National Park is in its 54th year.

A big chunk of their research goes into tracking down dead moose - bones and carcasses - around the island.

From these remains the researchers can pick apart the status and overall health of the moose population. And understanding moose is important to wolf research, since the wolves eat the moose.

It's like understanding the overall quality and quantity of food available at the grocery store. If there's good, abundant food available, you'd expect things to be good. If not, well - you get the picture.

When Rebecca Williams and I arrived at the Daisy Farm campground on Isle Royale, we were met by Rolf Peterson in his boat.

He said he'd just heard of a dead moose on Caribou Island and asked whether we would like to go see it with him.

A stroke of luck. We'd traveled by plane, car, and boat to get here, and here was our chance to see Peterson in action.

Here's a video of our trip with him. Is ripping the skull off a dead moose gross? I didn't think so, but you can be the judge.

So, what did you think? Vote by typing "gross" or "not gross" in the comment section below.

All this week, we’re visiting an island archipelago in Lake Superior.  Isle Royale National Park is so remote you can only get here by ferry or seaplane.  It's mostly wilderness.  Cell phones don’t work here. 

Wolves and moose have the run of the island.  It’s an ideal place for people who study the big mammals.

"A nine month old calf.  It looks like it might’ve just fallen down the rocky edge and never got up."

Rolf Peterson has come across a moose skeleton.  Mourning cloak butterflies are lapping up sodium from the bones.  With a yank and a twist, Peterson rips off the skull. 

"I think it’s least disruptive if we just saw off the back leg."

Much of what the world knows about wolves and their behavior comes from the long term research taking place on Isle Royale.

For 54 straight years, humans have been closely watching the top predator here, wolves - and their favorite prey, moose.

Durward Allen from Purdue first started the study in 1958. It was originally designed as a ten-year project.

Rolf O. Peterson joined the project after it had been running for 12 years. And under Peterson's leadership at Michigan Tech, the project continued from there.

For some, the magic of Isle Royale doesn't necessarily reside in the boat trip to the island.

Two days before Rebecca Williams and I left on our reporting trip, a friend and I were having lunch together.

"You're not riding on the 'Barf Barge' are you?!"

"The boat from Copper Harbor?"

"Yeah, I took that trip. We were on Isle Royale for a week. The first half of the week, all we could talk about was the boat trip over. And the second half of the week, all we could talk about was the boat trip back!"

On her trip, as the ship pulled out of Copper Harbor, the captain came on the loudspeaker.