They Hear the Sound of Distant Waves

Bird Behavior, Water and Shore
Wandering albatross at the Tasman Sea (photo from Wikimedia Commons)

17 October 2023

Like elephants, albatrosses can hear low frequency sounds below our range of hearing, a skill that’s very useful for their lifestyle.

Wandering albatrosses (Diomedea exulans) spend their lives making incredibly long journeys over the ocean. They are known to circumnavigate the Southern Ocean three times in one year, a distance of more than 75,000 miles (120,000 km).

Range map of wandering albatross (map from Wikimedia Commons)

To do this with the least amount of effort, they have the longest wingspan of any living bird — 8 to 12 feet (2.5 to 3.66m) — and use the wind to glide as much as possible.

The best gliding happens at updrafts over the water and the best updrafts are caused by large waves. So how do wandering albatrosses find those large waves? They hear them from very far away, possibly 1,000 miles.

According to Science Magazine, “Big waves produce a very low frequency sound, below 20 hertz, that can travel thousands of kilometers, particularly when they collide with long distance swells, such as when storms develop.”

Would an albatross approach or avoid these waves in the Southern Ocean?

video from Monthly Fails on YouTube

To figure out how the birds choose where to go, Samantha Patrick of University of Liverpool and her team tagged 89 albatrosses with GPS trackers at their breeding grounds on Crozet Island near Antarctica. When the birds returned a year later to breed again, researchers retrieved the tags and analyzed the data.

Geophysicists on the team combined the biologger recordings with infrasound monitoring data from Kerguelen Island in the Southern Ocean to build “soundscape” maps on the birds’ journeys. …

During their long-distance flights, the birds tended to change course whenever they encountered a loud infrasound, the team reports. The infrasounds often indicate wave turbulence, even storms—though it’s not yet clear how the birds make use of this information. The infrasound clearly impacted the birds’ behavior, although the scientists couldn’t identify a clear pattern of whether they avoided or aimed for these low frequencies.

— Science Magazine: ‘Voice of the sea’ may help albatrosses catch the perfect wind

We don’t know yet if they avoid or approach turbulent areas but we know they hear them. More study needed!

Turbulent sea (photo from Wikimedia Commons)

Read more in Science Magazine: ‘Voice of the sea’ may help albatrosses catch the perfect wind.

(photos from Wikimedia Commons, video from YouTube; click on the captions to see the originals)

ICYMI, There’s a New Male Bald Eagle at Hays

Birds of Prey
“V”, the new male bald eagle at Hays, 15 October 2023 (photo by Dana Nesiti, Eagles of Hays PA on Facebook)

16 October 2023

In case you missed it (ICYMI) there’s a new resident male bald eagle at Hays. The old male disappeared in early September. The new guy was obvious by late September.

“Dad” was one of the original eagle pair at Hays where nesting began in 2013. Pictured below in 2020 they fledged 20 youngsters in 10 years. The female was 4-5 years old when she arrived (14-15 years old now), but he was a full adult so no one knew his age. Bald eagles can live 30 years.

Hays bald eagle pair (female on left, “Dad” on the right) 8 Feb 2020 (photo by Dana Nesiti, Eagles of Hays PA on Facebook)

The newcomer, nicknamed V for visitor, became obvious as he set out to accomplish two important things in his early days of residence.

  • Vigorously defend his new territory against other males,
  • Court his new mate and cement their pair bond.
New male bald eagle, V, at Hays, 1 Oct 2023 (photo by Dana Nesiti, Eagles of Hays PA on Facebook)

This extra level of activity drew Hays eagle fans’ attention to his presence. Viewers have seen V chase away other bald eagles and mate with the Hays female.

This is typical behavior among new peregrines, too. Long time residents don’t work hard to show who’s boss, but the newcomers do. The first time it happened at the Cathedral of Learning peregrine nest it took me a while realize that new behavior was a clue. See how I figured out the first male switchover at Pitt in this vintage article: Who is he? New male at Pitt.

Meanwhile V and the Hays female will be busy getting to know each other as nesting season approaches in December.

New male bald eagle, V, flies past beautiful red maples at Hays, 15 Oct 2023 (photo by Dana Nesiti, Eagles of Hays PA on Facebook)

Check out the action in person at the Hays eagle viewing site and Dana Nesiti’s latest photos and news at Eagles of Hays PA on Facebook.

Read about the Hays eagle changeover in Mary Ann Thomas’ article in the Post-Gazette: With dad missing, Hays bald eagle finds a new, younger potential mate.

(photos by Dana Nesiti at Eagles of Hays PA on Facebook)

Why Does the Water Look Like Tea?

Trees, Water and Shore
Tannin stained water in Miners River, Michigan (photo from Wikimedia Commons)

15 October 2023

“Some tea with your river, Sir?” asks the caption on the satellite photo below where Rupert Bay meets James Bay in Quebec, Canada. James Bay’s incoming tide is pushing Rupert Bay’s tea-colored water upstream.

“Some tea with your river, Sir?” James Bay tidal water meets tannin-stained Rupert Bay, Quebec (NASA satellite image from Wikimedia Commons)
Tea-colored water is good.

In woodland and wetland settings, tea-colored water indicates that natural plant and water processes are occurring.

Frequently, water in streams and rivers becomes tea-colored from naturally occurring tannins, a chemical found in many plants around the world. The tannins can leach out of plants and plant debris and into groundwater, lakes, rivers, and streams. Although they can make the water more acidic, it’s important to note, tannins are not harmful to fish and wildlife.

This process occurs in many waterways that run through wooded areas and wetlands with high levels of plant mass and organic matter. Because there is always water flowing through these areas, tannins leach out of plants into the water, making it appear tea-colored.

— Mainelakes.org: Why is the Water Tea-colored?

Tannins leach from all kinds of plant debris, especially soaked bark, leaves and pine needles in the north woods. There are tannins in this magnified Woody Dicot Stem: Tannins in Early First Year Tilia. Its caption reads: “Many cells in the periderm, cortex and pith contain dark staining tannins.”

Woody Dicot Stem Tannins in Early First Year Tilia (photo from Wikimedia Commons)

Leaves made these tannin stains on pavement.

Leaf stains on concrete in Chermside (photo from Wikimedia Commons)

There are tea-colored creeks in northeastern Pennsylvania such as this one in Monroe County.

Tobyhanna Creek, Monroe County, PA (photo from Wikimedia Commons)

And there are some special lakes on Florida’s Panhandle coast where the tea-colored water flows into the Gulf of Mexico. This video describes the dune lakes of Walton County.

Tannins are OK to drink though they may not taste good. In fact, it’s the tannins in tea leaves that make the beverage tea-colored.

Orange water deposits are bad.

Bright orange deposits are bad, even when the water is clear. In western Pennsylvania the orange color comes from abandoned coal mine drainage. Here the outflow of a polluted culverted stream dumps into Chartiers Creek near Bridgeville. Yuk!

Inflow of abandoned mine drainage into Chartiers Creek near Bridgeville (photo by Kate St. John)

Blacklick Creek in Cambria County, PA is another example.

Blacklick Creek is orange from abandoned mine drainage, 2007 (photo by Kordite via Flickr Creative Commons license)

Don’t worry if the water is tea-colored.

Do worry if you see bright orange deposits. In western PA our orange creeks and streams are a case of Water Everywhere, But Not a Drop to Drink.

(credits are in the captions; click the links to see the originals)

p.s. GEOGRAPHY! Though far inland, James Bay is tidal because it is the southern tip of Hudson Bay which connects to the Atlantic Ocean. This watershed map shows Hudson Bay watershed in green. Note the tiny red circle I added for the location of Rupert Bay.

Primary drainage basins in Canada (map from Wikimedia Commons)

Fall Color in Early October

Phenology, Trees
Invasive burning bush shows off its fall color, Moraine State Park, 9 Oct 2023 (photo by Kate St. John)

14 October 2023

In October Pennsylvania’s Department Conservation and Natural Resources produces a weekly Fall Color Report with photographic samples from around the state. They promise this week will be colorful in the Northern Tier but we’re only getting started in southwestern PA. The fall color exception is Somerset County where high elevation creates a cooler climate.

PA fall color prediction for 12-18 Oct 2023 (map from PA DCNR)

As you can see, Pittsburgh’s Schenley Park is still mostly green …

… though a few maples are changing color.

The reddest maples are quick to drop their leaves so the predominant colors are still green and yellow.

Some flowers and fruits add a splash of color.

But for really gorgeous red and orange yesterday’s sunrise was the best.

Sunrise in Pittsburgh on 13 October 2023 (photo by Kate St. John)

“Red sky at morn, sailors forewarn” came true with today’s all-day rain.

(photos by Kate St. John, map from PA DCNR with link in the caption)

Peregrines Are Just Tiring Them Out

Bird Behavior, Peregrines, Water and Shore
Peregrine falcon looking for a meal (photo from Wikimedia Commons)

13 October 2023

When peregrine falcons migrate down the Pacific Coast in autumn they often pause at Canada’s Fraser River Delta to hunt shorebirds. Pacificnorthwestkate (@pnwkate) filmed one working a sandpiper flock at Roberts Bank.

Peregrines on the hunt hope to separate a single bird from the crowd because they cannot catch anything in such a tight flock. When a lone bird can’t keep up it becomes the peregrine’s dinner.

Flock of dunlin (photo from Wikimedia Commons)

Dunlin flocking behavior on the Pacific Coast changed after the peregrine population recovered in the 1990s. A study at the Fraser River Delta in 2009 found that dunlin quickly learned it was unsafe to roost at high tide during the day because peregrines were on patrol. Instead they began to spend high tide flocking over the open ocean, flying continuously for three to five hours.

A new study, published this month in Phys.org, looked at the interaction from the peregrines’ perspective and found that the falcons haze the dunlin flocks to keep them moving. Peregrine hunting success improved at the end of those 3-5 hours of continuous flying because the dunlin had to stop for a rest.

The hunting data showed that dunlins were at greatest risk of predation just before and just after high tide, and spent most of the riskiest period flocking. However, there was a sharp increase in kills two hours after high tide, because the dunlins were not flocking despite elevated risk. [They were resting.]

— phys.org: Peregrine falcons set off false alarms to make prey easier to catch, study finds

So the dunlin changed their behavior to avoid peregrine predation and the peregrines changed their behavior to wear out the dunlin. Peregrines have more stamina that dunlin.

Read more about the peregrines’ hunting strategy at Phys.org: Peregrine falcons set off false alarms to make prey easier to catch, study finds.

(credits and links are in the captions)

Birds Near Naples Are Flying More Than Usual

Bird Behavior, Musings & News
Rock pigeons in flight (photo from Wikimedia Commons)

12 October 2023

West of Naples, Italy there’s an area called Campi Flegrei (Phlegraean Fields) that contains the remains of a ruptured supervolcano. It has erupted many times over the past 315,000 years including an eruption 40,000 years ago that produced a huge ash cloud and may have driven the Neanderthals to extinction.

The region around the Gulf of Naples is very volcanic. There are vents at Solfatara in Pozzuoli where sulfurous steam emerges in an old crater. Pompeii and Vesuvius are across the Gulf.

Sulfur vents at Solfatara, Pozzuoli, Italy (photo from Wikimedia Commons)

Nonetheless it’s a lovely place to live by the Mediterranean. Towns, including Pozzuoli, Agnano and Bacoli, dot the crater edges and the flats between them. The area’s population is 500,000.

Scene from Pozzuoli, Italy (photo from Wikimedia Commons)

This slideshow of maps shows the towns among the remnants of the supervolcano.

In June 2023 scientists determined that there is a potential for rupture before an eruption at Campi Flegrei caldera, Southern Italy. (uh oh!)

In September the magma under Campi Flegrei began shifting again and caused more than 1,100 earthquakes in a month, some as strong as 4.0 and 4.2 on the Richter scale. The Guardian reported on 3 October: “The Italian government is planning for a possible mass evacuation of tens of thousands of people who live around the Campi Flegrei supervolcano near Naples.”

Years ago I learned that birds can sense when an earthquake is coming and they take flight before it hits. I suspect that the birds at Campi Flegrei are flying more than usual lately.

Read more about birds and earthquakes in this vintage article from 2016.

Birds Take Flight Before Earthquake

(photos from Wikimedia Commons, click on the captions to see the originals. Map credits: colorful relief map from Wikimedia, Fig. 1 map: Unrest at Campi Flegrei since 1950 from Potential for rupture before eruption at Campi Flegrei caldera, Southern Italy published June 2023 at Nature.com, Google map of the area with terrain)

How Heavy is a Cloud? and Other Weighty Subjects

Musings & News, Weather & Sky
Cloud on a scale (image from USGS)

11 October 2023

How heavy is a puffy white cloud? It depends on how big it is.

According to USGS, an average 1 kilometer by 1 kilometer cumulus cloud weighs about 1.1 billion pounds.

Notice that this calculation uses the metric system for the cloud’s dimensions because it’s so much easier to calculate the weight of a cloud using those units.

When the metric system began in France in the 1790s, the units had Earth measurements as their basis. A kilogram was the mass of water in a 10cm x 10cm x 10cm container (a litre). The cloud answer, above, was calculated in metric and expressed in kilograms, then translated to U.S. customary pounds.

Did you know that we use two measuring systems in the U.S.? Everyday things are described in U.S. customary measures (inches, feet, pounds) but, as described in Wikipedia, science, medicine, electronics, the military, automobile production and repair, and international affairs all use the metric system. Also, most packaged consumer goods in the U.S. have to be labeled in both customary and metric units.

All birds are measured in grams and centimeters. I can tell this common yellowthroat is being banded in the U.S. because there are inches on that ruler. But his tail is about 4.5cm.

Bird banding, common yellowthroat in hand (photo from Wikimedia Commons)

The U.S. is one of three major countries that do not universally use the metric system.

Map of metric and Imperial measuring systems from Wikimedia Commons

Why haven’t we completely adopted the metric system?

It comes down to three things: Time, Money and Congress. The change will cost time and money for U.S. industry, and designating an official measurement system requires an act of Congress. Whenever the subject comes up, lobbyists convince Congress to say “No.”

So for now we use two measuring systems.

p.s. Grams and pounds do not measure the same thing at all. Grams are a measure of mass (a fundamental property of matter). Pounds are a measure of force (the force of gravity on a mass).

If your mass is 68 kilograms, you are …
68 kg in Europe
150 pounds in the U.S.,
25 pounds on the Moon and still 68 kg,
0 pounds in outer space and still 68 kg
Your mass is 68 kg everywhere you go.

Read more here in Science News Explores: Explainer: How do mass and weight differ?

(credits are in the captions; click on the captions to see the originals)

Confusing Fall Chipping Sparrows

Songbirds
Tricky chipping sparrow, Frick Park, 7 Oct 2023 (photo by Charity Kheshgi)

10 October 2023

Migrating chipping sparrows (Spizella passerina) have just begun to arrive in Pittsburgh and they look different than they did last spring. The adults are fading and the juveniles, which never did match the adults, now resemble other species. We have a category for Confusing Fall Warblers. There ought to be one for Confusing Fall Sparrows.

From mid-March to mid-April chipping sparrows molt rapidly into breeding plumage with a rusty cap, a sharp white swatch above the black eyeline and rusty-orange tones on the wings.

Chipping sparrow in breeding plumage, April 2020 (photo by Lauri Shaffer)

In mid-August the adults being two and a half months of molting into duller non-breeding plumage, looking ragged in September and ending up with the brownish cap and muted facial markings of non-breeding plumage.

Adult chipping sparrow in October 2012 (photo by Steve Gosser)

Meanwhile the juveniles lose the spotted breast they fledged with and gain sharper facial markings. Sometimes they look like clay-colored sparrows which are indeed rare in Pittsburgh.

Let’s compare the young chipping sparrow at Frick Park to an October clay-colored sparrow: chipping on the left, clay-colored on the right below. These small photos are just like the long distance view in the field.

Chipping sparrow (by Charity Kheshgi) vs. clay-colored sparrow (photo from Wikimedia)

They look almost the same. What’s the difference?

  • The chipping sparrow has a strong black eyeline that extends all the way to its beak and its face patch has muted edges.
  • The clay-colored sparrow has no black between its eye and beak but it does have a dark “moustache” outlining the front edge of its face patch.
  • If you can see the top of the head, the young chipping sparrow may have thin white stripes but the clay-colored has a distinctly wide white crown-stripe.

And just to shake things up, there was a leucistic adult chipping sparrow at Frick last Saturday who looked as if he had been dunked face-first in white paint. His forehead, cheeks and throat were so white that it the camera had a hard time picking up the details.

Leucistic adult chipping sparrow, Frick Park, 7 Oct 2023 (photo by Charity Kheshgi)
Leucistic adult chipping sparrow, Frick Park, 7 Oct 2023 (photo by Charity Kheshgi)
Leucistic adult chipping sparrow, Frick Park, 7 Oct 2023 (photo by Charity Kheshgi)

Theorectically leucism (lack of pigment) is in his genes so his face will always looks like this no matter what plumage he’s in. He’s the only chipping sparrow I can identify as an individual.

p.s. More confusion: When American tree sparrows arrive later this fall they’ll resemble chipping sparrows in breeding plumage, except that the chipping sparrows will be in non-breeding plumage. Click here and scroll down to see American tree sparrows compared to chipping sparrows at All About Birds.

(photos from Charity Kheshgi, Lauri Shaffer, Steve Gosser and Wikimedia Commons)

Birds Take a Taxi to Correct For Climate Change

Climate Change, Migration
Male European pied flycatcher (photo from Wikimedia Commons)

9 October 2023

Birds like the European pied flycatcher (Ficedula hypoleuca) that winter in the tropics and southern hemisphere do not use weather clues to tell them when to fly north in the spring. Instead they cue on changing day length and return at the same time every year. But as Earth’s climate changes, spring comes weeks earlier than it used to and their migration timing is out of sync. Scientists in the Netherlands decided to give a few lucky birds a lift (a Lyft?) to Sweden and it made all the difference.

Pied flycatchers prefer to nest in or near oak trees where their nesting season is timed to correspond with the peak of caterpillar season. Unfortunately, spring is two weeks earlier now in the Netherlands, pied flycatchers arrive too late and have locally experienced a 90% decline.

Female European pied flycatcher carrying caterpillars (photo from Wikimedia Commons)

The old timing of Netherlands’ spring is now found in southern Sweden so scientists at University of Groningen in the Netherlands and Sweden’s Lund University decided to see what would happen to migration and nesting success if a few pied flycatchers were transported (by car!) from the Netherlands to suitable habitat in Sweden.

Anthropocene Magazine reports, “For three springs, starting in 2017, scientists from the University of Groningen in the Netherlands and Sweden’s Lund University caught newly-arrived Dutch female pied flycatchers and drove them by car to a nesting spot 570 kilometers (354 miles) away in southern Sweden that was already home to other pied flycatchers.”

Range of European pied flycatcher (map from Wikimedia Commons)

The experiment was wonderfully successful. The Netherlands’ females were in sync with the food supply and were twice as prolific as their Swedish counterparts who were locally out of sync. After spending the winter in Africa the former-Netherlands females returned to Sweden and so did their offspring!

Later the research team proved that migration timing is genetically inherited in European pied flycatchers by taxiing a few eggs laid in the Netherlands to Swedish nests. Those offspring returned to Sweden the following spring on the Netherlands timing.

Taxi service cannot be the answer to out of sync migration but birds are adapting on their own. During the study, banding still continued at Netherlands nests and some of those youngsters were found nesting in Germany, halfway to Sweden. They flew there on their own.

Read more about the taxi ride experiment in Anthropocene Magazine: For some birds, a “taxi” helps recalibrate out-of-sync migrations.

(photos and map from Wikimedia Commons; click on the captions to see the originals)

Chances Are You’ll Hit a Deer in PA

Deer
Deer crossing a road at dusk (photo by “i threw a guitar at him” via Flickr Creative Commons license)

8 October 2023

Fall is deer crash season in Pennsylvania. November, October and December, in that order, are the highest months for deer collisions because the animals are on the move in the breeding season.

During the rut, bucks travel an average of 3-6 miles per day searching for and chasing does in heat. Females split from their fawns when they find a mate and the youngsters wander. All age groups are crossing roads more frequently and all of them are distracted.

In Pennsylvania it’s especially important to stay alert because our high deer population increases the odds of a collision. Last month State Farm Insurance reported:

 State Farm estimates over 1.8 million auto insurance claims were filed across the industry from July 1, 2022 to June 30, 2023 involving animal collisions. Pennsylvania had the highest number of claims out of all the states, with an estimated 153,397 claims for the same time period.

Nationwide the odds of U.S. drivers hitting an animal are 1 in 127 this year. Drivers in West Virginia held on to the number one spot with the least favorable odds at 1 in 38. Montana (1 in 53), Pennsylvania (1 in 59), Michigan (1 in 60), Wisconsin (1 in 60) round out the top five most likely states to hit an animal while on the road.

— State Farm: Likelihood of Hitting an Animal While Driving, 12 Sept 2023

PennDOT’s heat map of deer-vehicle collisions on state roads shows particularly high deer collisions in several areas including Allegheny County.

PennDOT heat map of deer-vehicle collisions on PennDOT roads in 2022 (generated at crashinfo.penndot.gov)

In fact PennDOT statistics show that for 2018-2022 Allegheny County leads all Pennsylvania counties in deer-vehicle collisions. Your chance of hitting a deer in Pittsburgh is particularly high.

Deer spooked near the road in WV (photo by Mike Tewkesbury, Creative Commons license via Flickr)

Statewide the odds of hitting a deer — or a deer hitting you! — are 1 in 59 and probably higher in Pittsburgh. This means that each one of us knows someone who will hit a deer in the year ahead. It might be us.

Stay alert behind the wheel, especially at dawn and dusk. Watch out!

Read more about deer-vehicle collisions at WESA: Deer Danger: Pennsylvania is No. 1 in the U.S. for car crashes with animals.

(credits are in the captions; click on the links to see the originals)

p.s. An interesting statistic from Cornell University’s Community Deer Advisor website:

Hunter harvest is the primary cause of white-tailed deer mortality in rural landscapes, while deer in suburban landscapes are more likely to die in deer-vehicle collisions. [p.10]

Managing a deer herd via vehicle collisions is both inhumane and costly for community residents. [p.30]

— Cornell University: Integrated Approach for Managing White-tailed Deer in Suburban Environments