All in for albatross

October 7, 2019

“She’s one of a kind for sure,” said Holly Jones, who’s working with graduate student Wieteke Holthuijzen (above) as Holthuijzen studies the impact of a planned mice eradication on Midway Atoll. “She’s also pushing the bounds of science with her project—no previous students have used the methods she’s using to predict impacts of eradications.”

A place of beauty, birds and history calls to Wieteke Holthuijzen.

A biological sciences graduate fellow at NIU, Holthuijzen may spend her time these days in a lab, but she’s never really far from Midway Atoll National Wildlife Refuge.

One of the most remote atolls in the world, Midway lies at the far end of the extensive Northwest Hawaiian Islands. It’s perhaps best known as the historic site of The Battle of Midway, where the United States Navy successfully defended the land from a Japanese invasion in 1942 during World War II.

But these days, to Holthuijzen and other stewards of the environment, it’s one of the most critical areas for biological conservation in the world.

It’s home to the world’s biggest colony of albatross, large endangered seabirds often called “gooney birds.”

Laysan Albatross (Phoebastria immutabilis) at the Finger Piers at Midway Atoll. Source: Wieteke Holthuijzen

“They’re really the icons of the Midway,” says Holthuijzen, who has lived on Midway Atoll on two separate occasions. “I love them. I’ve always been a bird person, and they’re very charismatic.”

Having grown up in Idaho after her parents immigrated from the Netherlands, Holthuijzen first went to Midway in 2014 as a year-long volunteer for the U.S. Fish and Wildlife Service. She returned in 2016 as an invasive plant control specialist for AmeriCorps.

Along with the seabirds, she fell in love with the land, roughly 2.4 square miles of protected island disconnected in many ways from the rest of the world.

She’s determined to keep both alive and thriving.

Midway’s killer mice

Working toward her master’s degree under the guidance of NIU Associate Professor Holly Jones in the Department of Biological Sciences, Holthuijzen has spent the past year and a half in the Jones’ Evidence-based Restoration Lab studying the ecological impacts of invasive mice attacking the albatross on Midway.

To do so, she won one of the most competitive and respected fellowships in the country from the oldest graduate fellowship program available through the National Science Foundation.

“As soon as we talked, I knew Wieteke was very special and the kind of student any advisor would be incredibly fortunate to have,” says Jones, who’s worked with students and colleagues on numerous research projects, including a study of island recovery after invasive rodent removal in New Zealand and elsewhere throughout the world.

“Her fierce intelligence, passion for her subject, and analytical approach helped convince me that although her project was ambitious, she could pull it off,” she said of Holthuijzen. “Advising her has been an honor and a blast. I of course helped with her study setup and design, but mostly I’ve been able to stand aside and watch Wieteke soar.”

Laysan Albatross have a relatively high rate of reproductive success, hovering around 70% most years. Source: Wieteke Holthuijzen

Holthuijzen’s passion involves preserving and restoring nature, from land to wildlife. The albatross won her heart upon her first visit to Midway.

The seabirds spend more than 90 percent of their time at sea, only returning to the island — once their haven — to breed. Many remain steadfast on their nests as mice swarm, biting them bloody, while others abandon their eggs after repeated attacks.

Likely brought to the island on cargo ships during World War II, the mice slowly began to feed on the seabirds as food became scarce. Attacks were limited in 2015, but spread heavily in 2016 and 2017. The albatross don’t defend themselves.

“A lot of seabirds haven’t evolved with predators,” Holthuijzen says. “They don’t really have a strong anti-predatory response. They don’t see mice as a threat.”

The seabirds aren’t afraid of people either.

Laysan Albatross (Phoebastria immutabilis) and Black-footed Albatross (Phoebastria nigripes) on Midway Atoll. Source: Wieteke Holthuijzen

“You walk up to them and they nibble at your feet,” says Holthuijzen, also an avid graphic designer and photographer who’s made a hobby of photographing the birds up close and documenting her experiences on her “Wing It” blog.

She’s come across the carcasses of seabirds who’d been whistling on the sand the day before.

“You can’t forget it,” she says, “You want to do something.

“It’s surprising something so small — a mouse that we inadvertently brought — can have such a massive impact.”

Wieteke Holthuijzen first went to Midway in 2014 as a year-long volunteer for the U.S. Fish and Wildlife Service. She returned in 2016 as an invasive plant control specialist for AmeriCorps.

To ensure a robust albatross breeding colony into the future, the national nonprofit Island Conservation and its network of groups working to prevent animal extinctions throughout the world plans to remove all of Midway’s mice in July 2020.

Holthuijzen intends to take part in that effort, and regularly contributes entries on the topic to Island Conservation’s blog and National Geographic.

“Killing mice is not a fun thing. It’s awful. It’s not a happy thing to do,” she says. “At the end of the day, if your goal is to hopefully restore this system and help it become more resilient and robust, you have to do those things.”

While the eradication takes priority, she says, there’s also a need for a broader picture on its impact. That’s what’s demanding her attention.

Dropping everything

“It’s somewhat of a large, ambitious master’s project,” says Holthuijzen, who regularly pulls in help from numerous undergraduate students. “It was something that kept on growing.”

She’s spent the past year and a half analyzing the diet of Midway mice. Research like this, and at this scale, has never really been done before and will create a framework for future research involving invasive species on islands.

“The main concern is getting rid of these mice,” Holthuijzen says. “The science around it is kind of like the icing on the cake.”

What does her science involve? Well, to put it bluntly, mice droppings.

She analyzes mouse fecal samples sent to her from the island to get an idea of what they’ve eaten — from plant materials to insects. But that doesn’t really tell her how big a component each food source was in the diet.

So she’s also analyzing samples of mice hairs, and combining the results.

If she finds mice are feeding on invasive weed species, she’ll know to prepare for an increase in those species when the mice are gone. Same goes for insects and what they consume, as well as what consumes them. It all plays a role so she’s studying insects as well.

“The seabirds need the insects. Insect communities are important on seabird islands, but there are few studies on them,” Holthuijzen says. “Mice might be going after insect pests we don’t like. If the mice are gone, that might increase invasive insects. We’re trying to limit the problem from getting worse.”

Holthuijzen has an army of undergraduate students helping her sort invertebrates and is learning three separate fields of science for the project, Jones said.

Proud parents! A pair of Laysan Albatross eagerly await the hatching of their chick. Source: Wieteke Holthuijzen

And her creative talents and passion have helped build an outreach program, she said.

“She’s one of a kind for sure,” Jones says. “She’s also pushing the bounds of science with her project — no previous students have used the methods she’s using to predict impacts of eradications. It’s very exciting, and even more so since albatross conservation is at the core of the work.”

Greater purpose

Laysan love. Source: Wieteke Holthuijzen

With more than a year’s worth of funding left on her fellowship, Holthuijzen intends to process the data, release a manuscript, earn her master’s and keep at it. She’ll likely pursue a Ph.D., perhaps in the area of ecological restoration.

She knows Midway Atoll and places like it will always beckon.

During the few years she lived on the island, sleeping in an old officer’s quarters from World War II times, she felt surrounded by history. Bullet holes from the Battle of Midway still dot the facilities.

“You have to love birds to be out there because they’re everywhere,” she says. “It’s really loud with the screaming albatross.”

Along with studying the birds, life entails walks on the beach, swimming, snorkeling, kayaking, karaoke nights and random bowling in a broken-down lane once used by soldiers. There’s no WiFi, and the mail only comes once every two weeks or so.

Hard-working members of the Thai community take care of the facilities, earning money to support their families back home. All who live on Midway learn a bit of the language, celebrate Thai holidays and eat Thai food, along with soft-serve ice cream from an old machine.

“It’s a really quiet life,” she says.

A quiet, but rewarding life for those who’ve experienced it. And they’re doing all they can to keep it that way for the island’s most important residents.

“Places like Midway are out of sight and out of mind,” Holthuijzen says. “It’s great for people to know true wilderness exists. This is something we need to protect. Hopefully, we can inspire people to take an interest in the natural world around them.”

Media Contact: Jami Kunzer

About NIU

Northern Illinois University is a student-centered, nationally recognized public research university, with expertise that benefits its region and spans the globe in a wide variety of fields, including the sciences, humanities, arts, business, engineering, education, health and law. Through its main campus in DeKalb, Illinois, and education centers for students and working professionals in Chicago, Hoffman Estates, Naperville, Oregon and Rockford, NIU offers more than 100 areas of study while serving a diverse and international student body.

Naupaka Kahakai (Scaevola taccada) on North Beach with a Laysan Albatross (Phoebastria immutabilis) taking off in the background. Source: Wieteke Holthuijzen