Category Archives: Water and Shore

When Green Is Not Good

Peak Microcystis bloom, Lake Erie on September 19, 2017. Sample taken directly from the lake. (photo by NOAA GLERL)
Peak Microcystis bloom, Lake Erie, September 19, 2017. Sample taken directly from the lake. (photo by NOAA GLERL)

There's something wrong with Lake Erie.  Every summer when the water heats up it turns a thick soupy green, especially at the western end from Toledo to Sandusky and Point Pelee, Ontario.

The waves look like this or even worse.

Algal bloom on Lake Erie at Point Pelee (photo by NOAA Great Lakes Environmental Research Lab)
Algal bloom on Lake Erie at Point Pelee, June 2011 (photo by NOAA Great Lakes Environmental Research Lab)

The green is not good.  It's caused by Microcystis algae which produces toxins that kill fish and harm humans. The algal bloom was so bad in 2014 that the Toledo Water Authority told their 500,000 customers not to drink the water and not to wash dishes with it.

The bloom reaches it peak in autumn.  You can see the green muck from outer space in this satellite photo from September.

Lake Erie harmful algal blooms, Sept 2017 (satellite photo via NOAA GLERL on Flickr)
Lake Erie harmful algal blooms, Sept 2017 (satellite photo via NOAA GLERL on Flickr)

These algal blooms are triggered by warm water containing excessive nutrients:  nitrogen from sewage and/or phosphates from fertilizer.  In this century the water is warmer and it contains a lot of phosphorus flushed into the lake by heavy rain.  Cleveland.com explains that "The Maumee River contributes half of all phosphorus in the lake, with about 85 percent of it from fertilizer runoff."  (The Maumee enters the lake at Toldeo.)

We know how to fix this problem.  We've done it before.

Back in 1969 Lake Erie was plagued by pollution, toxic algal blooms and dead fish. One of its tributaries, the Cuyahoga River, caught fire in Cleveland.  Thanks to the Clean Water Act and the EPA established by President Nixon, Lake Erie was cleaned up quickly and stayed that way for 30 years.

Now the lake is in trouble again.  Michigan has already declared the lake impaired but Ohio officials are hesitating to do so because "they don't want to scare away swimmers and boaters."  Meanwhile people see and smell the algae and they're already staying away.

This 2013 video from KQED tells the story.

 

(photos by NOAA Great Lakes Environmental Research Lab on Flickr; video by KQED on YouTube)

Tundra Swans Overhead

Tundra swans in flight (photo by Steve Gosser)
Tundra swans in flight (photo by Steve Gosser)

This week's cold weather bought winds from the north and flocks of tundra swans over western Pennsylvania.  We usually hear them first, rush out to see them fly ... and then they're gone.

Where did they come from?  Where are they going?

Most of "our" tundra swans breed in the north central territory of Canada (Nunavut) and north of Hudson Bay.  This map from Xeno Canto shows their path in North America.  (Breeding range is pink.  Migration corridors are greenish yellow.  Wintering sites are blue.  I've added a purple dot for our location in western Pennsylvania.)

Map of Tundra Swan breeding, migration and wintering in North America (from Xeno Canto with location of recordings)
Map of Tundra Swan breeding, migration and wintering in North America (from Xeno Canto with location of recordings)

In late September tundra swan families assemble into flocks.  Then "our" swans move south through Canada's prairies, arriving in North Dakota and the upper Mississippi River valley in early October where they eat and wait until winter hits.

On winter's first blast they fly southeast to Chesapeake Bay and eastern North Carolina, passing over Pennsylvania on their way.

Tundra swans typically fly 30 miles per hour but on a strong northwest wind they can clock 100 mph and fly non-stop for 1,000 miles.

Most flocks don't stop in western Pennsylvania but they take a break here if the "kids" get tired.  That's what happened on Tuesday at Crooked Creek Lake.

Marge Van Tassel and a group of volunteers heard the swans coming and drove to a good vantage point to watch them come in.  Marge's photo shows them descending to the lake like large beautiful snowflakes.

Tundra swans landing at Crooked Creek, 7 Nov 2017 (photo by Marge Van Tassel)
Tundra swans landing at Crooked Creek, 7 Nov 2017 (photo by Marge Van Tassel)

 

Listen for their sound overhead and you may see tundra swans, too.

 

(photo credits:  flock in flight by Steve Gosser, flock landing by Marge Van Tassel, map and audio clip recorded in Michigan by Allen T. Chartier, #XC11851 from Xeno Canto)

Small Ducks Stop By For a Visit

Bufflehead female with two males (photo by Steve Gosser)
Buffleheads, female with two males (photo by Steve Gosser)

It's early November, the wind's from the north, and it's time for waterfowl. Here are two small ducks who stop in southwestern Pennsylvania on their way south.

Buffleheads and ruddy ducks hang out together in the winter, perhaps because they dive for the same food:  aquatic insects and crustaceans (crabs, crayfish, etc).  Buffleheads add mollusks to their diet (small mussels, clams, etc).  Ruddy ducks add plants and zooplankton.

Buffleheads (Bucephala albeola) are black and white with compact bodies and stubby bills.  Only 13.5 inches long, they fly fast and land abruptly.  They're actually the same size as a pied-billed grebe(*) but bufflehead males look larger because their round white-topped heads stand out.

Male bufflehead (photo by Steve Gosser)
Male bufflehead (photo by Steve Gosser)

Identifying female buffleheads is tricky, though, because their black heads have a white splash on the cheek that resembles -- at long distance -- a male hooded merganser or a female ruddy duck.

The best clue to a female bufflehead is that she's close to the males, as you can see in Steve Gosser's photo at top.

While buffleheads look like large ducklings, ruddy ducks (Oxyura jamaicensis) are shaped like bathtub toys(*).  At only 15 inches long they have big heads, thick necks and large slightly upturned bills.  Just like rubber duckies they often cock their tails, especially when asleep.

Ruddy duck (photo by Steve Gosser)
Ruddy duck swimming (photo by Steve Gosser)

In November ruddies are less "ruddy" than in the breeding season but the male retains his white cheek.

Ruddy duck male, late non-breeding plumage (photo by Steve Gosser)
Ruddy duck male, late non-breeding plumage (photo by Steve Gosser)

Females and juveniles have off white cheeks with a faint brown line.

Female ruddy duck (photo by Steve Gosser)
Female ruddy duck (photo by Steve Gosser)

 

Though buffleheads winter as close to us as Ohio, neither species stays in Pittsburgh for the season.  Stop by our rivers and lakes to see these ducks before they leave.

 

(photos by Steve Gosser)
(*) Descriptions adapted from Pete Dunne's Essential Field Guide Companion, an excellent resource for birding.

Sea Level Fingerprints

Fingerprint image from Wikimedia Commons
Fingerprint image from Wikimedia Commons

As ice sheets melt around the world, fresh water that used to be held on land is pouring into the ocean and sea level is rising.  But it's not rising uniformly.  The transfer of mass (water) from land to sea causes changes in Earth's gravity field.  Mirroring the ripples in gravity, the water is high in some places and low in others like the ridges on a fingerprint.

The mysteries of gravity *

Gravity is a force of attraction.  It works on everything and in both directions. The Earth's mass pulls you toward it while your mass pulls Earth toward you.  The bigger the mass, the stronger the object's gravitational pull.  Greenland with an ice sheet on top has more mass than Greenland without one, so as the ice melts Greenland's gravitational pull goes down.

As Greenland's gravity wanes it doesn't hug the ocean to its shore like it used to.  The water has to go somewhere so it rises in the tropics.  The effect is tiny, measured in millimeters per year.   The pattern is called a sea level fingerprint.

The pattern revealed

Many things contribute to sea level at any given point including the Moon's gravitational pull (causing tides) and the wind (causing waves) so it took lots of data and some serious number crunching to reveal Earth's gravitational fingerprint.  The data came from the GRACE satellite project.

GRACE satellites have been circling the Earth since 2002, measuring the pull of gravity on the globe below.  (Here's how GRACE works.)  Each orbit provides a snapshot.  Years of data show the change in gravity over time.  Most gravitational changes are due to the movement of water, especially groundwater.

Using GRACE data, scientists from NASA and the University of California Irvine mapped gravitational changes affecting sea level from 2002 to 2014, shown on the map below.  Blue means low water, red is high. The calculations were verified using readings of ocean-bottom pressure from stations in the tropics.

Sea level fingerprints (patterns of variation in sea level rise) calculated from GRACE satellite observations, 2002-2014. The blue contour (1.8 millimeters per year) shows the average sea level rise if all the water added to the ocean were spread uniformly around Earth. Image credit: NASA/UCI
Sea level fingerprints (patterns of variation in sea level rise) calculated from GRACE satellite observations, 2002-2014. The blue contour (1.8 millimeters per year) shows the average sea level rise if all the water added to the ocean were spread uniformly around Earth.
Image credit: NASA/UCI

Notice that the ocean has receded the most near Greenland at the rate of -2.5 mm/year.  That's 32.5 mm or 1.28 inches in the 13 years that GRACE measured it.  As NASA explains:

The loss of mass from land ice and from changes in land water storage increased global average sea level by about 0.07 inch (1.8 millimeters) per year, with 43 percent of the increased water mass coming from Greenland, 16 percent from Antarctica and 30 percent from mountain glaciers.

Click here to read more about the study and see an animated map of sea level changes 2002-2014.

Unfortunately some of the hardest hit places will be tiny Pacific islands and Florida.

Who knew that the sea has a "fingerprint."

 

(fingerprint image from Wikimedia Commons; click on the caption link to see the original. Sea level fingerprint map from NASA/UCI joint project using GRACE satellite data)

* p.s. Gravity is so mysterious that I initially described it incorrectly.  Thanks to Dr. Allen Janis, I've corrected the description. See his comment below.

High Tide Is Coming

Only eight years from now, high tide will be this much higher at Wellfleet Bay (photo by Kate St.John)
Only eight years from now, high tide will be this much higher at Wellfleet Bay (photo by Kate St.John)

Last weekend at Cape Cod I went on two outings at Massachusetts Audubon's Wellfleet Bay Wildlife Sanctuary led by Joel Wagner, a birder from Gettysburg, PA who now works at Wellfleet and Saco, Maine.

At low tide we visited the salt marsh and bay shore to look for shorebirds.  On our way there, Joel pointed out the Average High Tide markers with dates of future tides.  I was astonished to see that in only eight years the average high tide will move up from that distant 2017 marker to this one.

It's even worse in the decades ahead.  This photo shows the 2075 marker with the earlier years in the distance.  The 2025 marker is so far away that it's out of sight.  The trees in this photo will die when salt water reaches them.

Average high tide in 2075 will be here at Wellleet Bay (photo by Kate St. John)
Average high tide in 2075 will be here at Wellleet Bay (photo by Kate St. John)

The highest tides today, the spring tides, already swamp the 2017 marker.

Sea level is rising.  High tide is coming. Watch out if you live by the sea.

 

Unfamiliar with sea level rise?  Read more here at Yes, The Sea is Rising.

(photos by Kate St.John)

Staging At The Cape


Flock of Tree Swallows by Cindy Bryant on Vimeo, 12 Jan 2015, Central Florida.

Last weekend at Cape Cod I saw a swirling flock of tree swallows at their staging area.

Staging: Designating a stopping-place or assembly-point en route to a destination -- from The New Shorter Oxford English Dictionary.

Tree swallows (Tachycineta bicolor) breed as far north as the tundra/tree line in Canada and Alaska and spend the winter from Florida to Central America.  Their departure from western Pennsylvania is barely noticeable but on the East Coast they gather in salt marshes in huge flocks of a hundred thousand birds.  Their interim stops on migration are called staging areas.

In the evening tree swallows funnel down to the marsh in a tornado of birds.  At dawn they burst up from the roost, as shown in the Central Florida video above.

Last Saturday I saw thousands of tree swallows flying in tight formation at West Dennis Beach.  Though sunset was two hours away they flew low across the salt marsh, hovered and touched down on bushes, swirled up and around and away.

At the height of their swirling I took some photos but couldn't capture their magic.  However, this picture shows why they flew so fast and so close.  There's a falcon in the upper right corner with a swallow in its talons.  Perhaps it's a merlin.  I would never have noticed without this photo.

Thousands of tree swallows and one falcon with prey, West Dennis Beach, MA, 1 Oct 2017 (photo by Kate St.John)
Thousands of tree swallows and one falcon with prey, West Dennis Beach, MA, 1 Oct 2017 (photo by Kate St.John)

Here's an audio description of the tree swallows' fall migration at Connecticut salt marshes at Living On Earth: BirdNote®: Roosting Tree Swallows

It's worth an autumn visit to the East Coast to see this.

 

(video by Cindy Bryant on Vimeo, photo by Kate St. John)

Waiting For News … Again

Whimbrel (photo by Arturo Mann from Wikimedia Commons) This is not Hope.
Whimbrel (photo by Arturo Mann from Wikimedia Commons) This bird is not Hope.

News from the Caribbean, especially Puerto Rico, is horrific now that two Category 5 hurricanes have passed through the islands in just two weeks.  Homes, infrastructure and habitat are all destroyed. Our hearts and help go out to everyone affected by these storms.

Images of the widespread damage also have made me wonder:  Did birds survive these hurricanes?

Early this month one particular bird, a whimbrel named Hope, survived Hurricane Irma on St. Croix, U.S. Virgin Islands.  Did she survive Hurricane Maria?  We don't know yet.

North American whimbrels (Numenius phaeopus) that breed in the tundra of northwest Canada make long migrations to their wintering grounds in the Caribbean and South America.  To understand their migration The Center for Conservation Biology fitted a few of them with satellite transmitters when the birds made migration stopovers on Virginia's eastern shore.  One bird, nicknamed Hope, was tracked for three years beginning in 2009. Her transmitter was removed after it broke in 2012 but she still wears two colorful leg tags. Every year she returns in late August to St. Croix.

After Hurricane Irma I was encouraged on September 13 when The Center for Conservation Biology sent news that Hope had survived Irma.  The map below provides perspective on this miracle.

St. Thomas and St.John (purple pin markers) took a direct hit from Irma.  Hope spends the fall and winter on St. Croix (blue pin) at Great Pond (yellow star).  She was fortunate that Irma passed more than 45 miles north of her location.  St. Thomas and St. John were so devastated by Irma that survivors were evacuated to Puerto Rico and St. Croix.  (Click here to see a video of Hurricane Irma damage on the U.S. Virgin Islands, posted by the U.S. Navy.)

Then on the night of September 19 Hurricane Maria blew through the islands, passing only 10 miles south of St. Croix.  Hurricane force winds scraped the island for 7.5 hours before slamming Puerto Rico.  The southwestern corner of St. Croix was hardest hit.

As with Hurricane Irma it will take a while to find out what happened.

And I wonder: Did Hope make it through Maria, too?

We're waiting for news ... again.

Read more about Hope surviving Hurricane Irma -- and see photos of her -- in this article at The Center for Conservation Biology.

 

(photo of a whimbrel (this is not a photo of Hope) by Arturo Mann via Wikimedia Commons; click on the image to see the original)

p.s. For more news of the Virgin Islands see the Virgin Islands Daily News.

The Marbled Godwit’s Bill

Marbled godwit (screenshot of video by Steve Gosser)
Marbled godwit (from video by Steve Gosser)

Yesterday's blog described an online class from Cornell Lab for identifying shorebirds.  Here's a shorebird you'll really enjoy seeing, especially when you know who he is.

The marbled godwit (Limosa fedoa) breeds in northern prairies and at Hudson Bay, then migrates to the Atlantic, Pacific and Gulf coasts to spend the winter.

The bird is 16.5 to 19 inches long but that includes a 3-5 inch dark-tipped pink bill.  The females are larger than males, big for a shorebird but small compared to a roseate spoonbill (click here to see).

The godwit's bill is a great tool for finding food.  Its length allows him to probe deeply for small mollusks, bristle worms, insects, leeches (yes!) and sago pondweed tubers, and it's so sensitive that he can feel his prey without having to see it.

Click on the screenshot above to see Steve Gosser's video of a marbled godwit at Conneaut Harbor, Ohio early this month. Watch as she probes rapidly, then pulls up her beak to swallow a morsel.  She plunges her bill so deeply that her face goes underwater.

She was one hungry bird!

 

(screenshot from video by Steve Gosser)