Category Archives: Musings & News

U.S. Butterflies Declined 22% in Only 20 Years

Insects, Musings & News
West Virginia white (Pieris virginiensis) in 2008 (photo from Wikimedia Commons)

11 March 2025

A new study published last week in the journal Science analyzed butterfly surveys from 2000 to 2020 to determine the population status of each species in the continental U.S. The results were sobering.

Total butterfly abundance (all individuals of all species) decreased across the contiguous US at a rate of 1.3% annually, for a cumulative 22% decline in overall abundance between 2000 and 2020.

— Science: Rapid butterfly declines across the United States
during the 21st century

The only region of the continental US that didn’t suffer was the Pacific Northwest where the total population remained stable and the highly irruptive California tortoiseshell (Nymphalis californica) surged on and off as expected.

The study found that declines were common and increases rare.

Over our two-decade study period, 33% of individual butterfly species (114 of 342) showed significantly declining trends in abundance. Conversely, only 3% of species increased.

— Science: Rapid butterfly declines across the United States
during the 21st century

For instance, the West Virginia white (Pieris virginiensis), above, declined each year by nearly 20%, in part because they are fooled into laying eggs on invasive garlic mustard that kills their caterpillars. By now 98% of them are gone.

And in southern Texas and south Florida the Soldier butterfly (Danaus erisemus), a relative of the monarch, declined about 15% per year, which means about 96% of them gone.

Solider or Tropical Queen butterfly (Danaus erisemus), Loxahatchee, Florida, 2016 (photo from Wikimedia Common)

Learn more about the study and see the graphs of declining species in Science.

Meanwhile, what can we do to save butterflies? In some cases it simply means planting the butterfly’s host plant. The zebra swallowtail returned to Pittsburgh after an absence of 87 years(!) because many people planted its host plant, the pawpaw tree.

Population Hit by Bird Flu Recovered in Just 2 Years

Migration, Musings & News, Water and Shore
Barnacle goose closeup (photo from Wikimedia Commons)

9 March 2025

Every autumn barnacle geese (Branta leucopsis) leave their arctic breeding grounds and migrate to Europe. In 2021-2022, those wintering at Solway Firth, UK(*) became infected with highly pathogenic avian influenza (HPAI) H5N1 and 31% of them died. Even though their population had been devastated, they recovered to full strength in just two years. This can give us hope for North American birds hit hard by bird flu.

Wild barnacle geese breed in Greenland, Svalbard and Siberia yet each population has its favorite wintering site as shown on the map. Counts on the wintering grounds are directly tied to one breeding location.

Distribution of barnacle geese highlighting the studied population in 2021-22 (map from Wikimedia Commons)

The winter population at Solway Firth breeds at Svalbard.

Wintering flock of barnacle geese in the fog at Solway Firth (photo from Wikimedia Commons)

When bird flu hit Solway Firth in the winter of 2021-2022 researchers began a two+ year study to measure the demographic impact of the major HPAI outbreak on barnacle geese. During the outbreak they carefully counted dead goose carcasses and, thanks to fencing, were able to extrapolate for predation.

By February 2022 the barnacle goose population had dipped precipitously, but in the two years that followed the number of juveniles increased even faster. High birth rates on the breeding grounds quickly made up for the loss of adults.

Year to year maximum late-winter count of barnacle geese at Solway Firth. From Impacts of highly pathogenic avian influenza (HPAI) on a Barnacle Goose Branta leucopsis population wintering on the Solway Firth, UK

Researchers speculated that …

The large impact of HPAI-related mortality on the Solway Barnacle Goose population was rapidly recovered, probably through a combination of the widespread development of natural immunity and high levels of breeding success in the years following the outbreak.

— Impacts of highly pathogenic avian influenza (HPAI) on a Barnacle Goose Branta leucopsis population wintering on the Solway Firth, UK

In Pennsylvania, snow geese have been hard hit with wild bird flu. It will be interesting to watch how their winter population fluctuates in the eastern U.S. in the years ahead.

p.s. We don’t have barnacle geese in the U.S. Here’s look like.

Barnacle geese (center of photo) look unique but are similar in size to their nearest relative the cackling goose.

One barnacle goose with many cackling geese (photo from Wikimedia Commons)

Size comparison! Though cackling geese look like Canada geese they are much smaller. Thus barnacle geese are smaller than Canada geese we see in Pittsburgh.

Two cackling geese with a Canada goose (photo from Wikimedia Commons)

(*) Solway Firth forms the western border of Scotland and England.

Wild Bird Flu Now in Pittsburgh

Crows & Ravens, Musings & News
Crows hang out together (photo from WIkimedia Commons)

1 March 2025

Yesterday’s news was sobering for Pittsburgh’s winter crow flock when the Post-Gazette reported that 50 crows found dead in January tested positive for H5N1 highly pathogenic avian influenza. It was the first incidence of avian flu in Allegheny County in more than two years.

The Pittsburgh crows were collected on Jan. 24 and tested positive in preliminary tests for the deadly virus on Feb. 10, said Travis Lau, communications director for the Game Commission.

— Post-Gazette: First Pittsburgh cases of avian flu in years detected in American crows

It’s not hard to imagine how it happened. In January Pittsburgh’s winter flock of 15,000 crows roosts communally and fans out during the day as much as 50 miles to find food. The furthest travelers would have caught bird flu in an infected surrounding county and brought it to the roost. H5N1 is so contagious that it quickly spread to flock mates.

Crows moving in to roost near the Carnegie Science Center, 18 January 2025 (photo by Carol Steytler)

Apparently the crows knew what to do when death visited the roost. Crow watchers noticed that they changed the roost location a lot in January, perhaps avoiding sick birds and death locations. Maybe that’s why we haven’t heard of more crows deaths. Or maybe it simply takes weeks for the reports to reach us.

Crows in semi darkness (photo from Wikimedia Commons)

Meanwhile keep in mind that if you find a sick or dead bird you should not touch it!

Because of the highly contagious nature of the virus among birds, and the fact that, while rare, it can be transmitted to humans, the Allegheny County Health Department (ACHD), the Game Commission and other agencies urge the public not to touch sick or dead birds and report them to the Game Commission.

Anyone who sees a sick or dead wild bird should report it to the PA Game Commission at 833-742-9453.

Residents who suspect their poultry is infected with avian influenza should call the Pennsylvania Bureau of Animal Health and Diagnostic Services at 717-772-2852, option 1.

Residents who feel ill after contact with sick or dead birds should consult their primary care physician or the Pennsylvania Department of Health at 877-724-3258.

— Post-Gazette: First Pittsburgh cases of avian flu in years detected in American crows

Read more in the Post-Gazette: First Pittsburgh cases of avian flu in years detected in American crows.

See the 2021-2025 distribution of highly pathogenic (HPAI, H5N1) avian influenza in wild birds in the U.S. by county as of mid-February 2025 here at USDA.

She’s a Mother Again at Age 74+

Musings & News, Nesting & Courtship, Water and Shore
Laysan albatross, Wisdom, with her chick (5 Feb 2021 photo by USFWS Pacific)

17 February 2025

In case you missed it, the world’s oldest known banded wild bird has become a mother again at age 74. (She might be even older than 74.)

Wisdom is a female Laysan albatross who was banded (red Z333) as a breeding adult at Midway Atoll in 1956. Since her species cannot breed until age six and usually delays breeding until age seven or eight, Wisdom is at least 74 years old now, maybe even 77.

Wisdom breeds at the world’s largest albatross colony on Midway Atoll in the Hawaiian Islands chain. Like all of her species she spends most of her life at sea but returns to her breeding grounds each year to rejoin her mate, lay one egg, and raise the chick.

This year she returned as usual and laid her egg in late November. Then she and her mate took turns incubating for about 65 days and their egg hatched in early February. Here’s the chick with its parents. (Wisdom has a red leg band.)

74-year-old Laysan albatross, Wisdom, with her latest chick (video published 14 Feb 2025 embedded from USATODAY)

If Wisdom was a human she’d be part of the Baby Boomer generation. I cannot even imagine being a mother at her age!

Wild Bird Flu Update in PA

Doves & Chickens, Musings & News, Water and Shore
Snow Geese at Middle Creek, 4 March 2009 (photo by Kim Steininger)

11 February 2025

It’s been six weeks since hundreds of snow geese stricken with highly pathogenic (HPAI, H5N1) avian influenza were found dead and dying in Pennsylvania’s Lehigh and Northampton Counties on New Year’s Day.

By 24 January bird flu had killed 5,000 snow geese in Northampton County as well as raptors and scavengers including bald eagles and vultures and a snowy owl at Presque Isle.

Meanwhile the virus jumped from wild birds to an enormous commercial poultry farm: The first commercial poultry outbreak in PA since Feb 2024 was reported in Lehigh County on 27 January in a 50,000 commercial layer flock (egg farm). All commercial poultry facilities within a 10km (6.2 mile) radius have been placed under quarantine. (This is an example of why eggs are scarce and expensive.)

And so it comes as no surprise that the #1 location for snow goose migration in Pennsylvania — Middle Creek Wildlife Management Area near Kleinfeltersville — has been closed for the spring migration season.

The PA Game Commission announced ACCESS RESTRICTED AT MIDDLE CREEK on 3 February 2025.

HARRISBURG — Due to highly pathogenic avian influenza (HPAI) that is currently affecting many parts of the state, the Pennsylvania Game Commission is restricting public access at the Middle Creek Wildlife Management Area, effective Tuesday.

With the continued warming trends and the anticipated arrival of snow geese to Middle Creek, this decision was made out of an abundance of caution for human and domestic animal health. 

Beginning Tuesday 4 February 2025, the following areas will be CLOSED to all public access:

  • Willow Point Parking Lot and Trail
  • Archery Range
  • Boat Launch
  • White Oak Picnic Area
  • All shoreline access of the lake, INCLUDING fishing

The Wildlife Drive remains seasonally closed, and an extended closure is possible.

Hiking trails (with the exception of Willow Point Trail and Deer Path Trail) and the Visitor Center will remain open during regular business hours, and all events will take place as scheduled. 

All visitors are reminded:

  • If you have pet birds, backyard domestic poultry, or connections with commercial poultry facilities, you are STRONGLY discouraged to visit during this time to minimize transmission risk. 
  • You are HIGHLY ADVISED to remain in your vehicles while observing wildlife from roadways. 

Please remember the public plays a critical role in wildlife health surveillance. Report sick or dead wild birds to the Game Commission by calling 1-833-PGC-WILD (1-833-742-9453).

— PGC Press Release, 3 Feb 2025

Flocks at Middle Creek can contain 100,000 snow geese and 10,000 tundra swans at the peak of migration. This is what it looked like 3 years ago in 2022. It’s easy to see how these birds could spread contagious diseases.

video embedded from PennLive on YouTube

While bird flu (HPAI) spreads during spring migration remember to:

  • Always observe wildlife from a safe distance.
  • Avoid contacting surfaces that may be contaminated with feces from wild or domestic birds.
  • Do not handle wildlife unless you are hunting, trapping, or otherwise authorized to do so.

UPDATE, 28 Feb 2025 via Post-Gazette: The snow goose death toll in Lehigh County, Pennsylvania is now at 5,000 –> and these are just the birds that people could see and count.

Every Pigeon Counts

Doves & Chickens, Musings & News
Rock pigeon (photo from Wikimedia Commons)

10 February 2025

When you count birds next weekend for the Great Backyard Bird Count eBird has a lot of advice on how to do it. There are pages and pages on how to be accurate but for me the easiest counting error to fix is this: Don’t forget to count non-native species.

At the end of every eBird checklist the app asks, “Are you submitting a complete checklist of the birds you were able to identify?”

  • “YES” means “I wrote down every species.”
  • It also means that during data analysis researchers can infer that “No other species were present.”

If you don’t include pigeons, house sparrows or starlings but you answer YES you have biased your results.

Observer selection bias occurs when the evidence presented has been pre-filtered by observers. … The data collected is not only filtered by the design of experiment, but also by the necessary precondition that there must be someone doing a study.

— WIkipedia: Selection Bias

Some observer bias is hard to eradicate but this one is easy. YES there are pigeons on this light pole. Tell eBird how many.

Pigeons on a traffic light (photo from Wikimedia Commons)

Don’t worry that they are non-native. eBird colors the map orange outside their native range. Your checklists update the rock pigeon (Columba livia) map worldwide.

Explore Species Maps: Rock Pigeon (screenshot from eBird, August 2022)

So remember to count all the birds you see and hear during the Great Backyard Bird Count.

Silhouetted pigeons (photo from Wikimedia Commons)

Every pigeon counts!

Did You Know? Bread Is Bad For Me!

Musings & News, Water and Shore
close shot of ducks by David Tomic via Flickr Creative Commons license

6 February 2025

It sure is fun to feed the birds but not all food is good for them. Did you know that bread is junk food for birds? Just like us, ducks love junk food but it is bad as a steady diet.

Bread, crackers and our own junk food snacks have no nutritional value for ducks and geese. These foods are especially bad for ducklings because their little bodies are still growing and have special nutritional needs.

If a duckling depends on bread instead of a varied normal diet its wing bones will grow in a deformed manner called angel wing, a condition similar to rickets in humans. Both are permanent deformities caused by malnutrition.

Because this bird has angel wing it will never fly.

Duck with angel wing deformity from malnutrition (photo from Wikimedia Commons)

Since ducks don’t control their own junk food intake, and since we don’t know how much bread they ate before we got there, don’t feed bread to birds. Maine Audubon suggests what to feed them instead.

Some great options are lettuce or cabbage … Other things you can give them are: corn (not popcorn), rice, peas, broccoli, tomatoes, and most fruits (not citrus).

— Maine Audubon: Do’s and Don’ts of Duck Feeding
“Hey, Duck, no more! Didn’t you hear that bread is bad for you?”

Give this duck some lettuce.

Hey, no more! (photo by Andy Ihnatko via Flickr Creative Commons license)

Read more about bread and ducks in this vintage article from 2018.

Bread Is Bad For Birds

Starlings Are Declining in North America

Musings & News, Songbirds
Two common starlings in non-breeding plumage (photo from Wikimedia Commons)

5 February 2025

During January’s cold snap, flocks of European starlings (Sturnus vulgaris) suddenly swarmed backyard bird feeders and everyone wished they would just “Go away!”

Common starling flock in winter in Newark, Ohio (photo by Mary Ellen St. John via Wikimedia Commons)

As it happens starlings are going away, though maybe not quickly in your backyard.

Despite its success and large numbers, the European Starling is now in steep decline, like so many other species in North America. The current population is half the size it was 50 years ago – down from an estimated 166.2 million breeding birds in 1970 to 85.1 million. The species is also declining in Europe.(*)

— Cornell Chronicle: Starling success traced to rapid adaptation, Feb 2021, emphasis added

The decline is easy to see in red on eBird’s European starling Trends map, 2012-2022.

European starling: Breeding season population trends in North America, 2012-2022 (from eBird Status and Trends)

In just a decade starlings declined 14.9% in North America, mostly in the Midwest and especially Illinois where they are down 24.5%.

Despite this, many of us worry that starlings are having a negative impact on cavity-nesting native birds — but they are not.

Starlings often take over the nests of native birds, expelling the occupants. With so many starlings around, there is concern about their effect on native bird populations. Nevertheless, a study in 2003 found few actual effects on populations of 27 native species. Only sapsuckers showed declines due to starlings; other species appeared to be holding their own against the invaders.

— All About Birds: European starling account

“Only sapsuckers showed declines?” Fortunately this is not quite the case in Pennsylvania. Yellow-bellied sapsuckers have declined in certain regions of PA but in others they have increased. In areas of overlap with starlings, such as the western I-80 corridor, sapsuckers have increased. [I-80 is under the word “Pennsylvania” on the maps below.]

Meanwhile, starlings have declined more than sapsuckers overall and have not appreciably increased in the sapsuckers’ range. Compare the two Trends maps below.

Breeding population trends in PA 2012-2022: Yellow-bellied sapsucker (top) and European starling (bottom)

If you don’t like starlings, don’t worry. The problem is taking care of itself.

(*) In the UK the starling population dropped 80% in just 25 years from 1987 to 2012. This is very worrisome because they are a native bird in Europe.

Twirling Kudzu Like Spaghetti

Musings & News, Plants & Fungi
Kudzu draping trees in Atlanta (photo from Wikimedia Commons)

31 January 2025

If you’ve ever been to Atlanta you’ve seen areas like the one pictured above where invasive kudzu is draped over everything. You can see why it’s called “The vine that ate the South.”

Kudzu was introduced to the Southeast U.S. back in 1883 and given a healthy head start on its way to invasion.

The vine was widely marketed in the Southeast as an ornamental plant, … as a high-protein content cattle fodder and as a cover plant to prevent soil erosion.

By 1946, it was estimated that 3,000,000 acres of kudzu had been planted [in the U.S].

— Wikipedia: Kudzu in the United States, emphasis added

Planted!

Now that the genii is out of the bottle, how do we get rid of it? Good question.

The video below shows an interesting technique that is not enough to eradicate kudzu but is very satisfying to watch.

The “business” end of the equipment is a claw or grabber attached to a Tiltrotator on an excavator. It twirls the kudzu like spaghetti.

video embedded from TheRegrowthProject on YouTube

Snowy Owl? Or Plastic Bag?

Birds of Prey, Musings & News
Is that a snowy owl? Franklin County, PA 12 Jan 2014 (photo by Nancy Magnusson via Flickr Creative Commons license)

23 January 2025

Those who ventured out in this week’s bitter cold hoped to see birds from the far north who had just arrived on the wind. The typical way to find them is to drive past frozen fields watching for movement and scanning for anything that looks like a bird.

What’s that white lump in the field? Is it a snowy owl? Or a plastic bag?

Eleven years ago the winter of 2013-2014 was extremely cold and there was a huge irruption of snowy owls in the Northeast and Great Lakes. People photographed all of them, even the distant ones, to document them in eBird.

At top: Is that a plastic bag on that patch of snow? Below: Are there plastic bags or snowy owls in this photo? And how many?

Where’s the snowy owl? There are 3 in Jackson County, MI on 26 Dec 2013 (photo by Don Henise via Flickr Creative Commons license)

Is there a snowy owl in this picture?

Where’s the snowy owl in this picture? West Dennis Beach, Cape Cod, 17 Jan 2014 (photo by On The Wander via Flickr Creative Commons license)

Answer: All three photos have a snowy owls in them. The middle photo has 3 along the ridge top.

This winter we have not seen a big influx of snowy owls into Pennsylvania though there have been a couple of sightings.

screenshot of snowy owl sightings in the northeastern US in Jan 2025 (eBird species map as of 23 Jan 2025)

Recently there’s a snowy owl near Grantsville, Maryland which is often photographed from afar. A white lump?

If you’ve ever looked for a snowy owl and found a plastic bag you’ll enjoy the story and photos at The Search for Snowy Owls by Friends of the Fox River in Elgin, Illinois.