What can we learn from a pile of feathers and snarge?

Forensic ornithologist Carla Dove, of the Smithsonian Institution, examines collisions between birds and airplanes to determine which species are most likely to get entangled with aircraft in the first place

Vocabulary: snarge, forensic ornithology, trace evidence, diagnostic characteristics, morphological characteristics, non-native species

Next Generation Science Standards: LS2.A: Interdependent Relationships in Ecosystems, LS4.D: Biodiversity and Humans, ETS2.B: Influence of Engineering, Technology, and Science on Society and the Natural World. Builds towards performance expectations MS-LS2–3, HS-LS2–7, and HS-ETS1–3.

Common Core State Standards: Cite textual evidence (CCSS.ELA-LITERACY.RI.6.1, CCSS.ELA-LITERACY.RI.7.1, CCSS.ELA-LITERACY.RI.8.1, CCSS.ELA-LITERACY.RI.9–10.1, CCSS.ELA-LITERACY.RI.11–12.1)

Carla Dove (right) and her team at the Smithsonian Institution’s Feather Identification Lab. Credit: Chip Clark, Smithsonian

Collisions between birds and airplanes can result in a range of damage, the most severe being the kind that brought down US Airways Flight 1549 into the Hudson River in 2009. A flock of Canada geese snuffed out both engines on that plane shortly after takeoff. To prevent future bird-related calamities, airlines need to know which species are most likely to get entangled with aircraft in the first place.

That’s where forensic ornithologist Carla Dove, of the Smithsonian Institution’s Feather Identification Lab, comes in. From April through June 2016, she received the remains of more than 2,000 birds that had been struck by airplanes, with information on whether or not the plane had suffered damage. The Federal Aviation Administration and the military had sent the birds, wanting to know, in each case, the species. Black vulture? Canada goose? Horned lark? (The horned lark, by the way, is the most common collision casualty, not the Canada goose, as some might think.)

In the research wings of the Smithsonian National Museum of Natural History in Washington, D.C., Dove and her crack team of scientists solve more than a dozen of these avian mysteries every day. Sometimes they work with remains consisting of as little as a single brown feather, other times they must sift through a gruesome mix of plumes and innards known as “snarge.” Their detective work also relies on the Smithsonian’s vast array of more than 600,000 preserved bird specimens and, more recently, DNA processing.

Dove explains the CSI-like nature of her work, and how the data from these gory post-mortems can lead to saving birds’ lives in the long run.

Audio Excerpt “Feathers And Snarge: Identifying What’s Left After Birds And Planes Collide,” April 21, 2017. (Original Segment)

Print this segment transcript.

Questions for Students

  • Why is both molecular evidence (DNA) and morphological evidence important for Carla Dove’s work? Use evidence from the interview in your response.
  • Based on Dr. Dove’s estimation of the number of bird strikes in the US each year and the number that her lab processes, what percentage of yearly bird strikes are analyzed by Dr. Dove’s lab?
  • How do you think Dr. Dove’s research affects airport and airplane engineering and design?
  • How does Dr. Dove’s lab rely on museum specimens to do its work? Do you think it is important to maintain specimen collections, like ones at the Smithsonian of American Museum of Natural History? Why or why not? What other ways might scientists use these collections?
  • Using the FAA Wildlife Strike Database, create a list of bird species that are most commonly involved in plane strikes in your area. Research the habitat and niche of one of those species. Design a solution that might help airports in that area reduce the amount of collisions between that particular species and airplanes. Cite evidence from your research to back up your recommendations.

Activity Suggestions

  • Expanding on the final question above, have groups of students research wildlife strikes in different regions using the FAA Wildlife Strike Database. Have each group create a food web to visualize the ripples that a single bird strike could have on an ecosystems. Have student groups research usage data and economic impact of the airports in their chosen food web region. Based on their research, food webs, and conservation data, have students debate where efforts at airport redesign would have the most positive impact.
  • Dr. Dove’s feather lab is one of many that are working on cataloging the stomach contents of the Burmese Python to gauge its impact on the Florida Everglades. What does it take to catalog the stomach contents of a snake? If you and your students want to know more about that process, check out this paper from a group that examined the stomach contents of a Burmese Python from Everglades National Park and found three white-tailed deer! You can draw comparisons between the Burmese Python project and an owl pellet dissection. During each stage, draw parallels between what students do and what the researchers involved with this project do: have students isolate the fragments, identify those bones according to known specimens, catalog the contents, create a database that indexes the meals of each owl, estimate the intake of the owl with each pellet. With a bit more research into each of the organisms found in their pellets, students can create a food web based on classroom data.
Carla Dove, of the Smithsonian Institution’s Feather Identification Lab. Credit: Chip Clark, Smithsonian