2023
_NATURE ENVIRONMENT Ecology

_Antique Data Confirms Owl Discovery

DNA from a 173-year-old museum specimen at the Academy of Natural Sciences of Drexel University enabled ornithologists to describe two new species of Brazilian screech owl.

_Jason Weckstein

Weckstein is associate curator of Ornithology in the Academy of Natural Sciences of Drexel University and an associate professor in the College of Arts and Sciences.

_Therese A. Catanach

Catanach is a postdoctoral researcher in the Academy’s Ornithology Department.

An international team of researchers has described two never-before-recognized screech owl species: Xingu (Megascops stangiae) and Alagoas (Megascops alagoensis) living in precarious ecosystems within the Brazilian rainforest.

“The Xingu screech owl is endemic to the south side of the Amazon River in a region known for its infamous arc of deforestation, and the Alagoas screech owl is found in a few remaining fragments of isolated Atlantic Forest in northeastern Brazil,” says Associate Professor Jason Weckstein, who collaborated with a team of scientists on research published in Zootaxa.

The description of the new species resulted from years of work by scientists from Brazil and Finland, as well as the United States. The scientists were Sidnei M. Dantas, who led the study as part of his doctoral work at the Goeldi Museum in Belém, Brazil; Joiciane N. Oliveira of the Universidade Federal do Pará in Brazil; Alexandre Aleixo of the University of Helsinki; John Bates, curator of birds at the Field Museum of Natural History in Chicago; Weckstein and his colleague, postdoctoral researcher Therese Catanach.

species in peril

Both of the newly described species face threats from deforestation, but the Alagoas screech owl, right, is already likely critically endangered.

The team analyzed recordings of screech-owl vocalizations from across the distributions of these birds and paired these analyses with specimens and tissue samples.

The scientists’ analysis clarified that the screech-owl vocalizations from different regions were distinct from each other.

Scientists’ analysis clarified that the screech-owl vocalizations from different regions were distinct from each other.

Catanach and Weckstein then compared DNA that Dantas sequenced from frozen tissue collections with that of a 173-year-old tawny-bellied screech owl specimen in an Academy collection, which is a lectotype — a kind of icon for the species.

The lectotype, which was designated as a type specimen for Megascops watsonii, could then be included in the genealogy of screech owl species that the team published as part of the study, Weckstein says. In the future, this will provide a point of comparison for scientists studying the DNA of screech owls.

“That eastern Amazonia region is on its way to being in trouble, if we don’t take care of things,” Weckstein says.