I first met Walter Piper on the public landing at a lake in Oneida County where I’m fortunate to have a cabin built by my uncle in the early 1960s. I’ve been making my way to that little lake for most of my 60 years.
I don’t recall a summer when the lake hasn’t been home to a pair of loons. Because of my interest in loons I have a collection of photographs I’ve taken, including some showing loons displaying identification leg bands on our lake. So I made my way to the landing when I saw Piper put away his binoculars and begin paddling. I wanted to touch base with him about the nature of his visits.
Our visit was brief. We chatted and he handed me his card. I later visited his website loonproject.org where I learned about his research. I recently re-connected with him on the boat landing at Manson Lake near Rhinelander, Wisconsin.
Piper is a professor of biology at Chapman University in Orange, California. He’s entering his 27th year of studying the territorial behavior, reproduction and habitat selection of common loons in northern Wisconsin. By identifying loons through leg-band application, Piper and his team have followed the breeding lives of 65 loons. They’ve observed as adults 427 birds banded as chicks in the study area.
In Piper’s words, “the findings described in the loon-project website are supported by robust statistical analysis, burnished by peer review and presented in scientific-journal articles.” When speculations are made about observations Piper emphasizes they are only hypotheses. Piper said he and his team are scientists, not entertainers.
“We’re not afraid to use the very powerful words ‘we do not know,’” he said.
The common loon, Gavia immer, takes on many challenges in its quest to nest and reproduce in northern Wisconsin. Piper’s observations concluded that the black fly, Simulium annulus, is a deterrent that can have a significant impact on nesting success. That particular fly feeds on the blood of nesting loons. Some affected birds will abandon their nest when the infestation rate becomes intolerable.
Despite shoreline development, loons are hanging in there better than many other vertebrates, Piper said. In his study area loons have recolonized many lakes from which they had retreated. The loon population is thriving despite entanglements with hooks and fishing line as well as increasing methylmercury levels in northern lakes.
The common loon, the iconic symbol of the north, faces another challenge – warmer temperatures becoming the norm. Retired Wisconsin Department of Natural Resources fisheries biologist Frank Pratt has shown that Wisconsin’s waters have warmed and reduced fish populations – including walleye and cisco, an important baitfish. There’s a web of connectivity at work.
Merriam Webster defines anthropogenic as “of, relating to, or resulting from the activity of humans.” Piper describes climate change as the newest anthropogenic threat to loons. He refers to a study showing that on average bird-breeding ranges are moving northward by more than 2 kilometers per year. But the bird species included in the study varied greatly in their diets and habitats. Some birds are greatly dependent upon temperature for their survival while others are not. It’s difficult to project precisely how the geographic range of the common loon might be affected. Visit climate.audubon.org and click on “Common Loon“ to see an animated depiction. One can see the summer habitat of the loon move northward and be significantly reduced in Wisconsin by 2050 and gone altogether by 2080.
Piper is quick to say that Audubon scientists have attempted to distill the climate down to two main factors – temperature and precipitation. Their projections are likely to provide a crude estimate of the impact of climate change on loons, not a precise one. That’s the nature of climate models. In reality loons could retreat northward even faster than the model indicates or more slowly.
Agroecology is the study of ecological processes applied to agricultural production systems. Parallels can be drawn to the Audubon climate model and potential changes in agricultural production. It raises the question of whether agricultural crops will follow the trend of the loon – and if they are already doing so.
I spoke about climatic changes as well as the potential impact on farmers in Wisconsin and beyond with Jamie Patton, former University of Wisconsin-Division of Extension agent in Shawano County. She’s currently the senior outreach specialist with the Nutrient Pest Management Program at UW-Madison. I also spoke with Jerry Clark, UW-Extension agriculture agent in Chippewa County. I’ll share their answers in my next column.
Editor’s note: Greg Galbraith’s next column will be published in the July 18 issue of Agri-View.