Pick a Bird Brain Series 2023

In 2022, we celebrated the 50th year of counting and banding Birds at Hawk Ridge Bird Observatory!!  But there is a lot of truly incredible work going on behind the scenes by talented researchers that  is increasing our knowledge of Raptors and other birds with every passing year! This year’s Pick a Bird Brain series is going to focus on the amazing research projects that have been showing us more about these birds that fly overhead! Each month through the winter/spring we will feature a different project and you will have a front row seat to find out more about what we have been learning Dates for the programming will be aimed towards the third Tuesday of the month- with adjustments as needed- so keep your eyes out for more opportunities to hear from the researchers about what we are learning! Programs are free, but pre-registration is required, with a registration link provided in each presentation’s description.




June 20, 2023, from 7:00-8:30 pm

Dr. James Paruk: Loon Lessons

Recording of Program (YouTube)

James D. Paruk is one of the world’s leading experts on the Common Loon. Paruk has studied breeding and wintering loons in several states and Canada for 30 years. He recently wrote a book entitled, Loon Lessons: Uncommon Encounters with the Great Northern Diver published by the University of Minnesota Press. The book provides the most current detailed account of what we know about loon biology, behavior, and conservation. Currently, he is a Professor of Biology at St. Joseph’s College, in Maine. 

This event is co-sponsored by Hawk Ridge Bird Observatory, Duluth Audubon, and UMD Center for Environmental Education. Come join Jim for an enlightening and entertaining evening celebrating the Minnesota State Bird, our beloved Common Loon. For those of you who will not be able to attend in person, the presentation will be recorded and made available online at a later date on the Hawk Ridge YouTube Channel.

June 6, 2023, 7:00 pm

What have we learned from fifty years of fall raptor counts at Hawk Ridge?

Recording of program (YouTube)

Over 20 raptor species have been counted migrating at Hawk Ridge, but only 14 species are considered common enough during the fall migration to detect their population trend. Results from the Raptor Population Index indicated that counts since 1974 have increased for five species that reflect their increasing populations. In contrast, over that same period, counts for five species have declined or have mixed positive and negative trends. Four species have shown no perceptible change in counts, but they have been highly variable over the past fifty years. Causes for the population increases or decreases are complex, but are likely associated with banning the use of DDT in 1972, habitat changes on both breeding and wintering ranges, climate change, reduction in human persecution, and other species-specific factors. Jerry Niemi  will review the trends for each of these species and what we know or speculate are causes for the species population trends.

Gerald Niemi is a retired Professor Emeritus at the University of Minnesota-Duluth (UM-D). He was formerly Professor of Biology and Director of the Center for Water and the Environment at the Natural Resources Research Institute at UM-D. He received his Ph.D. in Biology at Florida State University in 1983 and was a Fulbright scholar in Finland in 1981. He has published over 160 peer-reviewed papers and over 130 technical reports and popular articles. His research has focused on birds, Great Lakes ecosystems, conservation, climate change, ecotoxicology, and the sustainability in the use of natural resources.

April 18, 2023, 7:00 pm

Using DNA metabarcoding to study the diet of raptors during migration

Recording of program (YouTube)

Hawk Ridge is famous for the stunning migrations of raptors it witnesses every year.  While much research has gone into understanding the timing and patterns of raptor migration, little research has been done to understand the diet of raptors during migration due to logistical research challenges.  Advances in the field of molecular biology in the past two decades have opened the door to new methods for studying migratory diet. In this Pick a Bird Brain Program, Lisa Brouellette will discuss the research she conducted at Hawk Ridge for her master’s degree at UMD. Samples taken from birds captured at the Hawk Ridge Banding Station yielded interesting results. There were some surprises, some not so surprising yet telling results, and it definitely identified some shortages of information in the available species DNA sequencing bank. Join us to find out more about migratory raptor diets!

Registration is required for this presentation. Register here.


March 21, 2023, 7:00 pm

Recording of program (YouTube)

Periodic Invasions of Northern Goshawks

Ordinarily, hawk count sites do not see large numbers of Northern Goshawks during fall counts because migration is unnecessary with prey species available year round in their home ranges. Juvenile males make up the majority of the goshawks annually seen at hawk watches in most years. However, about every ten years, the normal patterns change in significant ways, and there is over one hundred years of data demonstrating this obvious change which is called an invasion. What does an invasion entail, and what might be responsible for this dramatic change? There is a story here, but even that predictable story is changing as there has not been an invasion observed since the early 2000’s. 

Dr. Dick Green will look at historical observations made at three hawk watch sites: Hawk Ridge in Duluth, Minnesota, Cedar Grove in Wisconsin, and Hawk Mountain in Pennsylvania. He will puzzle out the pieces of the story that we know, and also attempt to understand the invasions by looking at the boreal forest community where Northern Goshawks live. Join us to take a look at this fascinating bird mystery!

Dr. Richard Green is a Professor Emeritus from the Swenson College of Science and Engineering, Department of Mathematics and Statistics at University of Minnesota, Duluth. He’s long had an interest in birds, visiting the Hawk Ridge Count regularly while he was still in grade school! His research interests are mathematical models in animal behavior and ecology, and he has taught courses in both. In 1982, he visited the Hawk Ridge Count on a day when 1229 Northern Goshawks were counted, in a period where some had predicted there would be no goshawk invasion. This got him asking questions about goshawks and their ecology and the search has continued ever since! He also serves on the Hawk Ridge Bird Observatory Research Committee.

February 23, 2023, 7:00 pm


The Forever Chemicals (YouTube recording)

The Forever Chemicals: What Do We Need to Know About Their Effects on Birds and How Will We Learn It?

The last two decades have seen a marked increase in concern over the effects of PFAS on humans and wildlife.  PFAS, or polyfluoralkyl substances, often called “the forever chemicals,” are persistent contaminants that enter the environment from a variety of sources, including manufacturing, landfills, and fire suppression. Among vertebrates, birds appear to be of particular concern for both exposure and effects. Reported effects on birds include early embryo mortality, failure to hatch, and high post hatching mortality. The specific mechanisms causing these effects are still poorly understood but may include disruptions of thyroid hormone signaling and fatty acid metabolism.

Dr. Matt Etterson will present findings from a recently completed study that surveyed birds of prey trapped during migration at Hawk Ridge or admitted as patients to The Raptor Center. For the study, up to 33 PFAS chemicals were investigated in blood samples from 11 species of diurnal and nocturnal raptors. Patterns of contamination were investigated in relation to the biology and life history of the species including size, diet, and taxonomy. Dr. Etterson will also provide a general background on avian PFAS work being done in Duluth and nationally as concern increases over this very large class of chemicals.

Registration is required for this presentation. Register Here

Dr. Matthew Etterson is the chair of the Research Committee at Hawk Ridge Bird Observatory, Duluth, MN, USA.  He holds a Ph.D. from the University of Minnesota (2000, Conservation Biology) and a BA from Yale University (1987, Mathematics and Philosophy).  Dr. Etterson has over 45 publications in avian ecology, on diverse topics such as ecotoxicology, reproductive ecology, and sampling methodology.  Dr. Etterson is an Adjunct Assistant Professor in the Biology Department and Integrated Biological Sciences Program at the University of Minnesota Duluth.  Dr. Etterson is also employed as a full time Research Ecologist at the United States Environmental Protection Agency, Duluth, MN, where he works on ecological risk assessment of contaminants.


The Secrets that Feathers Hold: Using Feathers to Trace Migration (YouTube recording)

January 24, 2023
The Secrets that Feathers Hold: Using Feathers to Trace Migration

At Hawk Ridge an average of more than 60,000 raptors are counted migrating through Duluth each fall, and over 2500 are banded. Some of these banded birds are recaptured at points further south but very few are recaptured or traced to their breeding grounds generally north of Duluth. As a result, very little is known about the distances they travel from their breeding grounds and the timing of their passage through Duluth during migration. Do birds from further north come through earlier than other birds of the same species breeding further south? 

In this Pick a Bird Brain Program, Emily Pavlovic will discuss the research she completed for her master’s degree at UMD using a combination of stable isotope analysis and banding return data to learn more about where Northern Saw-whet Owls, Sharp-shinned Hawks and Red-tailed Hawks are breeding, and whether the location of their birth impacts when they are likely to pass through Duluth on their way south.