Follow The Chickadees

Black-capped chickadees, 2012 (photo by CheepShot via Wikimedia Commons)

9 September 2021

The first three weeks of September are prime time to see warblers passing through Pittsburgh on fall migration. But finding these small, quiet, often greenish birds among the leaves is difficult.

How to find warblers? Listen for and follow the chickadees. Warblers are often with them.

Learn why in this vintage article: Local and Vocal.

(photo from Wikimedia Commons; click on the caption to see the original)

Landscape of Fear

Adult Cooper’s hawk (photo by Dave Brooke)

8 September 2021

Fear causes an inability to thrive in humans. Now a new study shows this is true of birds as well.

As a grad student at University of Massachusetts in Amherst, Aaron Grade decided to parse out why urban nestlings are lower weight than their rural cousins. It’s well known that urban settings have poor habitat, altered food sources and more predators but the likelihood of predation is lower there because urban predators have so many other food choices.

House wren at nestbox (photo from Wikimedia Commons)

Grade wondered if fear play a role so he set out 38 house wren nest boxes and loudspeakers in participants’ backyards in urban, suburban and rural western Massachusetts. During the nesting season participants played back the sounds of two predators of house wrens: Cooper’s hawks (pictured at top) and eastern screech-owls (below).

Eastern screech-owl (photo by Bobby Greene)

Though there was no actual danger, parent house wrens responded to the sounds by guarding their young and perhaps feeding them less. In the end nestlings in these playback settings were 10% underweight no matter what habitat they grew up in.

The study found that whether the birds are hurt or not, their nestlings are underweight and less likely to survive if the family lives in fear.

“These landscapes of fear,” says Grade, “can have a greater effect on behavior and survival than the actual predator itself.”

Science Daily: How landscapes of fear affect the songbirds in our backyards

Birds and humans cannot thrive in constant fear.

Read more about the birds at Science Daily.

Read about humans at Low Birth Weight Babies and Black Women: What’s the Connection?

(photos by Dave Brooke, Wikimedia Commons and Bobby Greene)

p.s. This is also a lesson for birders: Avoid using playback of predator sounds, especially during the spring and summer nesting season!

Some Peregrines Don’t Migrate

Peregrine in flight (photo from Wikimedia Commons by Imran Shah)

7 September 2021

As fall migration continues, raptors swell the southbound stream. At the Allegheny Front Hawk Watch (closest to Pittsburgh), broad-winged hawks peak in September, sharp-shinned hawks in October, red-tails in late October, and golden eagles in November. Peregrines are rarely seen, averaging just 34 individuals per season. Their numbers peak in the first week of October.

Peregrines are rare at the Allegheny Front Hawk Watch because they are not numerous to begin with and the watch is far from their typical migration routes. However, many peregrines are never counted on migration because they don’t migrate at all. It depends on where they breed.

Arctic peregrines are truly migratory. Their food sources — nesting shorebirds, seabirds, and songbirds — leave the arctic from July through September so the peregrines must leave, too. A decade ago The Southern Cross Peregrine Project (SCPP) satellite tracked a dozen arctic peregrines wintering in Chile and found that those that breed in northeastern Canada always leave around the September equinox.

From there, unless major weather diverts them, northeastern arctic peregrines typically fly due south to join the Atlantic Flyway. In the spring they track west and follow the Central Flyway. The map below shows five years of satellite tracking of an arctic peregrine, “Island Girl,” on her migration south from Canada to Chile (red) and returning in the spring (blue).

5-year map of arctic peregrine -- Island Girl -- migration routes (map from Southern Cross Peregrine Project)
5-year map of an Arctic Peregrine’s migration routes (Island Girl map from Southern Cross Peregrine Project) NOTE: As of 2021 frg-org is no longer on the Internet

Meanwhile adult peregrines in eastern North America generally don’t migrate at all. Urban peregrines remain on territory year round because their food supply is constant (pigeons) and actually increases in the fall when migratory songbirds arrive for the winter. Adult peregrines may move a short distance during winter scarcity but not necessarily south. Juveniles definitely wander.

The animated PA Game Commission map below shows nine months of wandering by a juvenile peregrine that hatched at the Gulf Tower in Spring 2002. The bird left Pittsburgh on 1 July and wandered to New Jersey, the Chesapeake, Virginia, Maryland and Pennsylvania. This was only the beginning.

Telemetry map of juvenile peregrine falcon banded at the Gulf Tower in Spring 2002 (animation from PA Game Commission, 2003)
Telemetry map of juvenile peregrine falcon banded at the Gulf Tower in Spring 2002 (animation from PA Game Commission, 2003) This animation is no longer available on the PGC website

Juvenile peregrines wander until they reach maturity at age two, then wander to find a breeding territory. Good nesting “cliffs” are scarce so these floaters may wander for years. When they finally claim a nesting site they won’t leave home unless an even better site becomes available.

Peregrine falcon flies by in Trenton, MI, September 2012 (photo from Wikimedia Commons)

Do Pittsburgh’s peregrines migrate? No. I see them in person and on the National Aviary nestcam from November through February when migratory peregrines are in South America.

Pittsburgh’s peregrines stay close to home.

Read more about Canada-to-Chile migratory peregrines in these vintage articles: Going The Distance and Follow an Arctic Peregrine on Migration.

(photos from Wikimedia Commons; click on the captions to see the originals. Telemetry map of juvenile peregrine falcon banded at the Gulf Tower in Spring 2002 (animation from PA Game Commission, 2003). This animation is no longer available on the PGC website)

Birds and Women at Work

Falconer with gyrfalcon at Hohenwerfen Castle, Austria (photo from Wikimedia Commons)

6 September 2021

On Labor Day, let’s take a look at birds of prey working with women.

Falconry in Europe evolved from a sport of the nobility to a career accessible to the middle classes. Though considered a man’s sport, aristocratic women in medieval and early-modern Europe took part in large numbers and became renowned for their falconry skills, often better than men. When falconry declined in the 18th century far fewer women were involved, making this 1880 portrait of Die Falknerin (The Falconer) and the following 1881 illustration of the same woman in Die Gartenlaube unusual in its rarity. Who is this falconer holding a Eurasian kestrel in a land that speaks German?

Die Falknerin, portrait by Hans Makart, 1880

Nowadays women falconers work at raptor centers, aviaries and bird abatement services that use falcons and hawks to move nuisance birds.

At top, a woman falconer works with a gyrfalcon at the Salzburg Regional Falconry Centre at Hohenwerfen Castle, Austria where they hold daily flight demonstrations with various birds of prey. The falconers live at the castle so they can better take care of the birds.

Below, Sabrina Fox flies a Harris hawk in Portland, Oregon in 2018 to move the winter crow flock out of the city center.

Sabrina Fox, falconer, Portland, OR, 2018 (screenshot from Urban Falconry in Portland, Oregon by OPB)

In Idaho, women at the World Birds of Prey Center in Boise fly a peregrine falcon and a harpy eagle in a flight show.

Falconer with peregrine falcon, World Center for Birds of Prey, Idaho, 2011 (photo by Jitze Couperus via Flickr Creative Commons license)
Falconer with harpy eagle at World Center for Birds of Prey, Idaho, 2011 (photo from Wikimedia Commons)

And in Pittsburgh, women falconers work with birds at the National Aviary. In 2011 Cathy Schlott displayed a lanner falcon at an event at WQED.

Cathy Schlott of the National Aviary holds a lanner falcon, Horace, on the glove, 2011 (photo by Sharon Leadbitter)

Learn more about the history of women in falconry and their current contributions in this abstract of the Women and Sustainable Hunting Conference at the University of Wageningen, the Netherlands, July 2016.

Visit the National Aviary to see birds and women at work.

(photos from Wikimedia Commons, screenshot from OPB video, Jitze Couperus via Flickr Creative Commons license, Sharon Leadbitter; click on the captions to see the originals)

Leaf Miner on White Snakeroot

Leaf mine on white snakeroot, 19 August 2021, Frick Park (photo by Kate St. John)

5 September 2021

Have you seen an unusual white squiggle on a green leaf? The pattern was made by a leaf miner, a tiny insect larva that eats a path between the top and bottom surfaces of the leaf.  The path ends when the larva is ready to pupate. When the insect departs it leaves a hole.

There are many tiny moths, beetles, sawflies and flies that make leaf mines. Some create blotches. Others, like this one, make serpentine paths. You can identify the insect(s) that made the paths — or at least narrow the number of species — by noting the type of mine and identifying the plant host.

This serpentine leaf mine was on white snakeroot (Ageratina altissima) in Frick Park on 19 August. Based on the Illinois Wildflowers list of insects that feed on Ageratina altissima, here are two possible suspects that create serpentine leaf mines and live in Pennsylvania.

  • The larvae of a tiny fly, Liriomyza eupatoriella. (NOTE: While researching this insect I discovered Charley Eiseman, an expert on leafminers and author of the only photo of the bug at bugguide.net. More on Charley Eiseman below.)

If you want to know more about leaf miners, go to the expert. Check out Charley Eiseman‘s book, Leafminers of North America or visit his BugTracks blog where he writes about all kinds of insects. He’s even discovered new species.

(photos by Kate St. John, screenshot of bugguide.net and photo from Wikimedia Commons)

The Devil’s What?!

(photo taken at Moraine State Park 2 Sep 2021, by Kate St. John)

3 September 2021

Seven of us retired ladies went birding yesterday morning at Moraine State Park. After a flurry of warblers we found this pink fleshy thing on the ground, the size an index finger.

As we tried to identify it someone suggested a fungus called devil’s fingers. Linda uploaded a photo to iNaturalist and the answer came back right away: the devil’s dipstick.

Umm, yah. “Small devil.” We dissolved in laughter.

After we’d wiped the laughing tears from our eyes we googled for more.

Mutinus elegans, a member of the Phallaceae family, is also known as elegant stinkhorn or headless stinkhorn.

As the egg-shaped fruiting body matures it ruptures and the spongy spore-bearing stalk emerges; fully grown, it may be from 0.4 to 5.9 inches long and 0.6 to 0.8 inches thick. The stalk is hollow and strongly wrinkled overall; its shape is cylindrical below, but it gradually tapers to a narrow apex with a small opening at the tip.

Wikipedia account: Mutinus elegans

The one we found was an old specimen. When new, the stalk stands up and the upper third is coated with a stinky greenish-brown spore-containing slime that attracts flies to bear away the spores. Here’s a newer specimen, photographed in Florida.

There are even more suggestive specimens here and here.

The devil’s what?!

p.s. At least one of the ladies in our group is not retired but she is a grandmother so I invoked my poetic license to describe us.

(top photo by Kate St. John, second photo from Wikimedia Commons; click on the caption to see the original)

A Tip For Identifying Confusing Fall Warblers

A confusing fall warbler, autumn 2011 (photo by Steve Gosser)

2 September 2021

The remnants of Hurricane Ida held back bird migration for two days in Pittsburgh but the logjam has broken. Today and tomorrow hold the promise of many migrating birds in southwestern Pennsylvania including mixed flocks of confusing fall warblers. Here’s a tip on how to identify them. This even works hours later at home with your reference guides.

In the field with a hard-to-identify bird, write down every feature you see as if you were going to draw the bird. Don’t forget habitat and behavior.

Details, details, details! The more details the better. If you get only a fleeting glimpse describe whatever jumps out at you.

The details will be useful when you get home and look at field guides.

Let’s try it on this bird.

At first glance (squint your eyes to see less):

  • perched in a tree
  • smaller than a sparrow; warbler size
  • charcoal gray back
  • yellow chest
  • white wing bars
  • plain face
  • (Under the Tail is important too but we can’t see it here.)

More details:

  • yellow chest has pale gray necklace with stripes

Even more details:

  • broken eye ring
  • throat above necklace is yellow
  • some stripes on flanks
  • greenish patch on back
  • maybe a white patch on topside of the tail

Tools: The Warbler Guide by Tom Stephenson and Scott Whittle has free downloadable tools that show all the warblers side by side. Get them here: QuickFinder PDF (my favorite) or QuickFinder JPGs.

Practice! Use this technique in the field. See how I used it to identify another confusing fall warbler: Orange Crowned or Simply Yellow.

So what bird is pictured above?

Leave a comment with your answer and — most important! — the details that led you to that conclusion.

UPDATE, 3 Sept 2021, the answer is: Magnolia warbler

(photo by Steve Gosser)

Disappearing In The Sand

Coquina clams, open shells, Corpus Christi (photo by Pinke via Creative Commons license)

31 August 2021

Coquina clams (Donax variabilis) are tiny saltwater molluscs found on sandy beaches from Virginia to Texas. Their variable colors are beautiful and at only 3/4 inch long they are just the right size for collecting. I usually find an empty half shell rather than two joined like butterfly wings (above).

Colors of coquina clams (photo by Florida Fish & Wildlife via Flickr Creative Commons license)

Since I only pay attention to empty shells I never thought about where they live and how they get there until I saw this video. Watch two coquina clams disappear in the sand.

(photos from Pinke via Flickr and Florida Fish & Wildlife on Flickr)

What do Ospreys have in common with Golden Retrievers?

Golden retriever at the beach (photo from Wikimedia Commons)

31 August 2021

When dogs get wet they shake it off.

So do ospreys.

It’s a bit trickier to shake off in the air.

(photo from Wikimedia Commons, video embedded from YouTube, tweet embedded from @marktakesphoto)