Blog Birding #405

At Avian Hybrids, Jente Ottenburghs discusses the famous Haida Gwaii population of Northern Saw-whet Owl and whether it should really be considered a unique species.

More than one year ago (in January 2018 to be precise), I wrote a blog post about the evolutionary history of the Northern Saw-whet Owl (Aegolius acadicus). A genetic study revealed that two subspecies – brooksi and acadicus – are genetically differentiated with extremely low levels of gene flow. In fact, there might not be any gene flow. I then provided the following advice: “a genomic approach is necessary to be sure.” The authors followed my suggestion (or they were already working on it) and revisited this system using genomic data. Has there been gene flow or not?

Corey Finger of 10,000 Birds shares the experience of finding a number of extraordinary species in a relatively short time frame.

I still had a few hours before I had to pick up Desi from school and I was torn between going home for a nap or looking for more birds. Finding more birds won out and I took the short ride to Jamaica Bay Wildlife Refuge where I enjoyed a Rose-breasted Grosbeak at the feeders, the singing Yellow Warblers, and the generally expected birds at Jamaica Bay in May. After scanning the West Pond and the South Marsh I made my way into the South Garden, planning to bird my way up to the north end of the North Gardens. Then a brown bird flew up from the path into a bare tree: my first thought from my binocular-less look was that it was a thrush. Binoculars to eyes and…umm…what?

We know that ravens, even among other corvids, are highly social creatures, but recent research published at Phys.org, finds that an individual bird’s emotions are influenced by their emotions of their peers.

The researchers report that the observer ravens that had watched their paired comrade behave badly took much longer to investigate the third box presented to them, suggesting they had been negatively emotionally impacted by watching their fellow raven behave negatively. Those observer ravens who had witnessed normal behavior, on the other hand, also exhibited normal behavior when tested. The researchers suggest their experiments indicate that ravens can experience negative emotional contagion.

Laura Erickson writes of her love for the singularly bizarre and fascinating Yellow-breasted Chat.

I saw lots of chats during my Big Year, mostly in Delaware where they belong—their population is densest in the Southeast, most especially in Arkansas, Louisiana, Mississippi, and Alabama, and they range north to Pennsylvania across to south-central Wisconsin; they also breed throughout the American West where they find suitable scrubby habitat.

The Salton Sea is one of Southern California great birding hotspots, but receding water levels and increased salinity make the area less habitable to birds, as Garrison Frost of Audubon California warns.

One of the fastest disappearing species appears to the be the American White Pelican which, according to surveys, has declined from a high of 20,000 birds in 2008 to fewer than 100 now, according to aerial surveys conducted by the California Department of Fish and Wildlife. Audubon’s own surveys shows a similar drop-off on recent years. This decline is largely the result of the Sea’s increased salinity, which is killing off the tilapia upon which the birds feed.

Join the American Birding Association at www.aba.org!