Flamingos (dancing birds?) of the Spanish Marshes

Where the confluence of two rivers, Tinto and Odiel, empty into the Atlantic in southern Spain, a huge coastal marsh system has developed over tens of thousands of years. Ancient civilizations, like the Phoenicians, Greeks, and Romans recognized the rich fishing grounds and mudflats that supported such a wealth of diversity of life, including wading birds, shorebirds, raptors, hare, deer, wolf, and lynx, and they built hunting lodges and port cities on the edge of the marshes. Today, the bustling Andalusian city of Huelva (claimed to be the oldest city in Europe) lies in the center of more than 17,000 acres of marsh protected in the Odiel Biosphere Reserve.

Las Marismas (marshes) of the Odiel and Tinto rivers are renewed twice a day as the high tides return to bring nutrients inland from the sea. This is what nourishes the more than 300 species of both resident and migratory birds that stop over here on their way from Africa to breed in Europe. (Map from “Nature-watching in Europe“)

Rare European Spoonbills were discovered to be breeding here in large numbers in the 1970s, and this led to the declaration of the area as a UNESCO reserve in 1983. As a result, the Odiel marshes have become one of the premier wetland habitats for European birds, but the area is more than just marsh. It features salt pans (natural and man-made), lakes, forest, heathland, sandy shore, tidal channels, and of course, the rivers — diverse habitat for a multitude of species.

Odiel marshes are the perfect habitat for these European (white) Spoonbills that use their long flattened beak to sweep the shallow waters for crustaceans, mollusks, worms, and tiny fish.
In addition to the iconic Spoonbills and a wide variety of shorebirds feasting on mud-dwelling invertebrates, the Greater Flamingos breed here in great abundance. The shallow salt pans are filled with brine shrimp which forms the bulk of their diet. The commercial salt mining operation here actually provides more habitat for birds to use for foraging in a set of about 16 rectangular pools, some of which you can see in the background.
Flamingos are filter-feeders. They turn their heads upside down in the water, pushing the water in and out with their tongues over their overly large lower bill that is lined with horny plates that trap the tiny shrimp.
Greater Flamingos are actually white birds with accents of pink (unlike the Americas variety). But the extent of pink coloration is determined by the carotene in the shrimp in their diet, and there is plenty of that here.
Our guide, Manu Mojarro, showed us how prolific the brine shrimp are in these salt pan waters where the salinity is many times more concentrated than sea water.
In order to separate the shrimp from the salt water, flamingos pump water over the plates of their lower mandible about 20 times per second, and must consume about 270 grams of food per day (approx 1/2 pound). Their shrimp diet is supplemented with fly larvae, mollusks, crabs, and small fish, which they stir up by swishing their feet around in the mud.

Greater Flamingos gather in the hundreds to breed in these marshes on a small island where they build their mud mound nests right next to each other–like the ones in the photo below from Algeria.

View of the Greater Flamingo colony at Ezzemoul, northern Algeria, from a paper by Samroui and Laid, 2013 in Avian Biology Research.

Finding a mate in a dense crowd of hundreds or thousands of individuals must be challenging, but flamingos are noted for their dancing skills and the collective group ballet that is used to pair individuals up. Older flamingos with longer necks might have an advantage here, but the entire group performs a synchronized dance to rev each other up for the grand finale.

Sir David Attenborough narrates the action…

The word Flamingo in Spanish is “flamenco” — is it just coincidence that the flamenco dancer’s moves strongly resemble that of the bird’s during its mating dance?

Birds and blooms in the Tagus river estuary of Lisbon

We spent part of a day acquainting ourselves with the beautiful environs of central Lisbon and then took a birding tour of the variety of habitats in the Tagus river estuary the following day. This is the largest estuary system in western Europe, with an area of more than 80,000 acres where as many as 50,000 waterfowl overwinter.

We’re not in Kansas anymore — or in Minnesota! Spring wildflowers were in great abundance here in the meadows surrounding the salt marsh.
Red Poppies were a delight to find along roadsides and in parks. i have always loved the orange California poppies, but these are even more spectacular.
Unbelievable color!
The contrast of the very old structures that probably date back to 16th or 17th century with the modern constructions of wind farms and electrical utilities.
We saw a variety of birds still utilizing the estuary wetlands, but there were just a few representative examples left at the time in the spring. Flamingoes here are mostly white with pinkish tinges of color on their back and wings.
Dozens of Glossy Ibis grazed in wet meadows and marshes, but were very skittish and took off with the slightest disturbance.
At least 8 species of shorebirds foraged in the mud at low tide, moving from pool to pool en masse.
But the strangest sight we viewed on this trip was White Storks nesting communally on power structures everywhere — in urban, rural, and in natural settings.

In a little over three decades, the White Stork increased from around 1000 individuals in Portugal in 1995 to about 15,000 individuals today. And one of the reasons for this increase in the face of near extinction is the access that the storks have to foraging in landfills for the nutritious remains of fishermen hauls, restaurant leftovers, and household garbage. in fact, now White Storks will not try to nest farther than about 10-12 miles from the landfills.

Storks are rather handsome birds with black wingtips and long, red bills. They stand about 3 feet tall and weigh about 7-8 pounds. Their usual diet of small invertebrate and vertebrate species found in wetlands has been supplanted by the much easier to acquire landfill organic waste.
Storks are powerful flyers, which might be why this bird that likes to nest on chimneys and rooftops in urban areas was linked to folk tales about the delivery of babies. The storks apparently have great fidelity to the nest site where they raised last year’s chicks, but the pair do not stay together on their wintering grounds in tropical Africa. So they may or may not meet up in subsequent years to rear another batch of chicks.

Amorous Stilts

It’s Springtime in South Carolina, and the birds are paired up and prepping for the egg-laying season — meaning there is a lot of mating going on. I spotted a couple of Black-necked Stilts at the Bear Island wildlife management area on Edisto Island doing a little courtship routine. The female was bent over (but not foraging) while the male walked a complete circle around her as she turned, always presenting her rear end to him.

The male has just begun his circle of the female here. The sexes are identical in color, but can be distinguished by their behavior toward one another.
Finished with his circling maneuver, he tweaks her tail feathers with his beak.
An interesting behavior and communication with the female. You can just barely see that these birds have intensely red iris color in the spring. Is that a signal of breeding readiness, I wonder?
The male hops on her back, and tweaks the top of the female’s head with his bill. But if there was a sperm transfer (called a “cloacal kiss”) in this series, my camera didn’t catch it. This was as low as his rear end got toward hers.
And he hops off after about 5 seconds on her back. Look at the position of his left leg — who knew birds could bend this flexibly? This is the equivalent of our ankle joint — bending forward!
Cementing the pair bond with a little body to body contact. Now you can see the bright red iris they both have (click on the image to enlarge it) during the breeding season. Unless the light is just right, the iris looks black.

Fish for breakfast

Photography buddy Debbie spied an Osprey on a tree branch right next to the road as we were driving into the Pinckney Island wildlife refuge near Hilton Head, South Carolina, so we stopped for a photo. Not only did the bird stay put on its perch, it calmly proceeded to eat its morning snack of some long-bodied fish right in front of us.

Freshly caught, perhaps a needlefish or something like it, probably an easy catch for this Osprey.
Piece by piece, the fish gradually disappears down the Osprey’s gullet.

A few birds

Photography buddy Debbie promised we would see ”a few birds” during our stay at Hilton Head island in South Carolina…and so we did on our adventure to Tybee Island north beach.

A flock of Black Skimmers flew right in front of us. My camera was already zoomed to the max on another bird unfortunately, so I couldn’t begin to capture the whole flock.
Royal Terns posed like statues along the shore, only flying up when someone walked (obliviously) through the middle of the group.
Tiny Sanderlings skittered over the surface of the shoreline, poking their beaks into the jellies that had washed up.

Coming soon…to your neighborhood

Babies, babies, babies!

New fluffy Cygnets
New Mallard ducklings
New Canada Goose goslings
New Tree Swallow chicks
New Kildeer chicks
New Sandhill Crane chicks — Photo by Debbie Reynolds
New Pied-billed Grebe chicks
New Eastern Kingbird chicks

O frabjous day! Callooh! Callay!” Springtime is on the way!! (Apologies to Lewis Carroll)

Scenes from Puerto Vallarta (part 1)

Once again we tried to visit the estuary located just a mile from where our ship was docked, but weren’t sure they were even open for business if the pandemic had severely impacted tourism at this port. But we did see a few interesting critters while waiting to see if the gates at Estero El Salado would open.

A tributary of the estuary crosses the main road from the port, and we could see Yellow-crowned Night Herons and Iguanas lined up on the branches of the mangroves there.
Yellow-crowned Night Herons seem especially sleepy in the morning hours, dozing in the warm sun on mangrove branches.
A Green Iguana was also warming up in the morning sun. These 3-foot long lizards were once very common along river systems in this area, and were frequently found in the mangroves. But many were taken for eating and for the pet trade, and their numbers are drastically lower now.
A female Black-cheeked Woodpecker was hunting in some tropical vines hanging from a sycamore looking tree along the road. The male has an all-red crown with yellow just above the bill.
Apparently the woodpecker had been drilling out the contents of a seed pod.
Streak-backed Orioles are common here.
Another common bird of the tropics — a Tropical Kingbird.

By 10 am. the estuary gates still hadn’t opened so we abandoned those plans and walked on up the street to find some other entertainment. See the next post for what we found instead.

Birds by the bay

Arriving at the peak of low tide the other evening gave us some great looks at a diversity of shorebirds foraging along the shore of Eloise Roemer bird sanctuary on Alameda Island in San Francisco Bay.

Lots of Dunlin, Willets, Curlews, Great Egrets, Pelicans, Cormorants, Avocets, — wow, what a shorebird mecca this tidal area is!
A couple of Long-billed Curlews resting on one leg…
A trio of Willets…
Double-crested Cormorants, White Pelicans, and kayakers enjoy the quiet water of this sheltered bay.
Low Cormorant on the totem pole gets the small rock, I guess.
Stilts and Yellowlegs hunting in the shallows.
Greater (i think) Yellowlegs have beautifully edged wing and back feathers when you can see them up close.
Black-necked Stilts have such delicate toes at the end of those long, pink legs.
and on the grassy side of the beach, a beautiful little Western Bluebird hunting for insects in the waning light.

Down by the bay

A quick trip to the marshy shoreline of Alameda Island in San Francisco Bay yesterday evening gave us an impressive view of hundreds of busy shorebirds feasting on mud-dwelling critters.

And the skyline of San Francisco across the bay from the island…
And a lovely sunset with little shorebirds still foraging for last crumbs from the mud.


A fellow blogger reminded me that over the course of a year, or a decade, we write a lot of words about a lot of photos on our blogs. I have been writing this blog since July 2011, roughly a month after I retired. Somehow, I completely missed celebrating the 10th anniversary of “Backyard Biology” in July this year, and so after the end of 2021, I’m summarizing the highlights and milestones of the blog in this post.

This was the featured animal on the first ever Backyard Biology post — a Japanese beetle eating my raspberry plants.

Since that first entry, I have written 1689 posts, and the blog has had 415,000+ visitors (some just came once, some visited several to many times), with a total of more than 640,000 views during the past ten years. During that decade span I’ve written more than 307,000 words, which is about the equivalent of the word length of 4 novels, and I’m now finding that I am repeating myself, writing about the same topics in much the same way. And so the posts are more infrequent, and are now focused more on the natural history of the global backyard, rather than just my own backyard.

During the past 10 years, the post with by far the most views on one day (722) was on May 23, 2018, “Waterfall Extravaganza” in Hraufossar, Iceland, where there are 900 meters of continuous waterfalls streaming from a monster glacier and falling over impervious lava rock.

Every view in Iceland is spectacular, and I captured quite a few of them. But this post seemed to pique the most interest in readers. This is a very small section of a long ridge of waterfalls draining into the Hvita River in western Iceland.

The same three or four posts seem to generate the most interest every year, probably as a result of a Google search for an answer. The top three each year tend to be: “How many seeds in a sunflower seed head?”, “Gigantic black horse fly”, and “Scary-looking, big, black wasp alert”. The post on sunflower seed heads gets about 30,000 views a year. Inquiring minds want to know!

This 6.25 inch diameter sunflower seed head had 1080 seeds in it. The beautiful geometric pattern of spirals is the most efficient packing of seed material into the given space — where the numbers of seeds in a given clockwise and counter-clockwise spiral are consecutive Fibonacci numbers. This post is from September 30, 2012.

This year, the most viewed post (528 views on October 17) was “Reflections”, which included some photos of images reflected in rippling water, like this one of Bald Cypress in the Mobile-Tensaw river delta.

In fact, the posts from our Fall trip to Alabama, a unique environment I had never seen before, were the most viewed posts of the entire year. Lagging far behind in views (350) was the post I entitled “Apocalypse”, thinking that would really capture readers’ attention.

On August 17, winds drove the smoke from the Caldor fire in the foothills of the Sierra Nevada mountains into Desolation Valley where we were camped at 8100 feet.

And now it’s time to find some new material to showcase on Backyard Biology, with adventures near and far in 2022. Happy reading!