David Cothran@davidcothranphoto

Naturalist and photography instructor with Lindblad Expeditions/National Geographic. Currently working in Egypt.


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David Cothran

I photographed this pteropod (Clione limacina) in about fifteen feet of water off Goshamna on the southern side of Hornsund, the southernmost fjord on Spitsbergen, in Svalbard. Pteropod means “wing-foot”, which is a great description of these delicately beautiful little creatures. They are gastropod mollusks, essentially shell-less snails that have adapted to a pelagic swimming lifestyle by repurposing their muscular foot into a pair of stubby wings. They are also called sea butterflies due to their fluttering movement in the water. Clione is found in sub-freezing waters of both the Arctic and the Antarctic, a fragile little dancer in the world’s coldest seas.
#marinelife #arctic #svalbard #lindbladexpeditions #natgeoexpeditions


David Cothran

A pair of Adélie Penguins (Pygoscelis adeliae) stand on a small iceberg, beside a large chunk of ice rubble fallen from another berg, near the Fish Islands off the west coast of the Antarctic Peninsula. Adélies are the smallest of the three species of “brush-tailed” penguins (the other two, also in the genus Pygoscelis, are the Gentoo and the Chinstrap) They are also the most southerly in their distribution and, along with the Emperor Penguin and the Snow Petrel, nest further south than any other birds. They are an entirely Antarctic species, found only around the coasts of the white continent. Like most penguins Adélies look quite comical on shore, hopping and waddling on their short legs, but in the sea they are transformed into perfect little hydrodynamic bullets, tapered on both ends and capable of swimming at amazing speeds with just a stroke or two of their stiff, flipper-like wings.
#penguin #antarctica #iceberg #lindbladexpeditions #natgeoexpeditions


David Cothran

The National Geographic Explorer sits at anchor in Garibaldi Fiord, in Chilean Patagonia, on a very icy day. Garibaldi is one of the few glaciers in the Cordillera Darwin that is advancing, but on this particular day it was calving huge towers of ice into the fiord, one office-building-sized piece after another, hundreds of thousands of tons of ice that rapidly broke up and filled the fiord completely with floating brash that varied from the size of loaves of bread to large trucks. When we speak of a glacier retreating or advancing, we are referring only to the position of the terminus, the end of the glacier where it calves into the sea or melts away on land. Whether advancing or retreating, glaciers are always flowing downhill from their origins in mountains or ice caps and can still dump prodigious amounts of ice into the fiords they have carved. This was a challenging and super cool day for Zodiac cruising!
#patagonia #glacier #ice #ship #lindbladexpeditions


David Cothran

A Pied Kingfisher (Ceryle rudis) hovers momentarily over the wide calm waters of the Nile, a little downstream from Aswan. This is near the northwest limit of this species’ large range, from North Africa to southern China. Kingfishers are a moderately large and very diverse family of birds, with 114 species distributed on every continent except Antarctica. Most of them, like the Pied, feed on fish and aquatic invertebrates caught in shallow plunge dives, but many other species are restricted to woodland habitats where they prey primarily on insects. The Shovel-billed Kookaburra uses its wide, flat bill to dig for worms in mudflats! Pied Kingfishers are somewhat atypical in their black and white plumage - many others have brilliant markings in blues, greens and orange-red hues.
#kingfisher #Egypt #Nile #birdinflight #lindbladexpeditions


David Cothran

An adult male (probably, judging by his shape) polar bear (Ursus maritimus) walks beside a melt-water pool on old pack ice in Lancaster Sound, in the Canadian Arctic. The sight of a 1,000+ pound warm-blooded mammalian predator strolling across the ice, relaxed and completely at home in the middle of hundreds of square miles of frozen ocean wilderness is, I think, the ultimate confirmation of the power of evolution. The bear isn’t really alone in the wilderness, it’s part of a rich community, but most elements of this world (invertebrates, fish, seals) are hidden below the ice. Apex predators like polar bears are often the most visible parts of an ecosystem, and they are thrilling to see, but we should remember that they represent only one piece of the large and complex web of life that includes them. When they are threatened, as so many top predators are, huge numbers of smaller, less visible creatures are endangered as well.
#polarbear #ecosystem #apexpredator #lindbladexpeditions #natgeotravel


David Cothran

The Kalv Glacier (often incorrectly called the Pia Glacier) pours down from the Cordillera Darwin into Pia Fiord, about 50 miles west of Ushuaia on Tierra del Fuego (thanks to my glaciologist friend @e.izagirre for the correction on the name). Physically the Darwin Range seems like an extension of the Andes, but geologically it is quite distinct. In this shot the glacier is flowing between two small mountains of metamorphosed sedimentary rock that is mid-Cretaceous in age (around 80-90 million years - about as old as the oldest parts of the Andes). Behind the ice there is a thousand-foot-tall grano-diorite headwall that is more than twice that age. Those rocks were emplaced two hundred million years ago, along the coast of Pangea, around the time it began to break up. Slow uplift and recent glacial erosion have carved them into the spectacular peaks we see today.
#chile #glacier #geology #lindbladexpeditions #natgeotravel


David Cothran

An adult male Killer Whale (Orcinus orca) surfaces on a glassy calm afternoon in Johnstone Strait off the northeast coast of Vancouver Island in British Columbia. Now that I’m posting mostly in original aspect ratio, I’m occasionally going to repost images that I’d previously shown cropped to 1:1. I enjoyed the creative effort of doing that but some images really do look better as they were shot (I think that’s true for this one), so I’m giving them a second visit. Male Killer Whales remain their matrilineal pods all their lives, honing the group feeding techniques and elaborate socialization taught to them and passed down to the next generation by the eldest females.
#killerwhale #calm #britishcolumbia #lindbladexpeditions #natgeotravel


David Cothran

Three Southern Elephant Seal (Mirounga leonina) bulls in a bit of a shouting match at the end of breeding season on the beach at Gold Harbor on South Georgia. These three are all adult males and competitive for places in the breeding hierarchy. This year they were probably beta males, constantly testing the boundaries of the beachmaster’s harem. Next year one of them may become the alpha, but he’ll have to fight hard for it. Off-season pushing and shoving like this may help to begin the establishment of a dominance hierarchy, but the real test will come in the serious fights next winter.
#elephantseals #southgeorgiaisland #males #lindbladexpeditions #natgeotravel


David Cothran

A White Tern (Gygis alba) makes a tight maneuver in the bright blue skies over Ducie Atoll, in the Pitcairn Group in southeast Polynesia. These lovely, delicate seabirds, also called Fairy Terns and Angel Terns, are found throughout the tropical seas of the world. They nest on the branches of low trees, but don’t build any nest structure at all. The single egg is simply laid on a small wrinkle or depression in the bark of the upper surface of the branch and incubated there by both parents. It’s a really remarkable adaptation, which frees the birds from the need to find and carry nesting materials. When the chick hatches it clings tightly to the branch in the same spot, motionless and nearly invisible, until it is ready to fledge!
#whitetern #pitcairn #seabird #lindbladexpeditions #natgeotravel


David Cothran

A Mountain Goat (Oreamnos americanus) leaps across a cleft in the limestone cliff of Gloomy Knob in Glacier Bay National Park. Mountain Goats, which are not true goats - that is they are not members of the genus Capra, as are all other goats - are beautifully adapted for life in alpine habitats. The pads of their hooves are soft and rubbery, so that they can deform over tiny irregularities in rock surfaces, giving the animals very sure traction and allowing them to accomplish astounding feats of climbing. Unlike most hoofed animals, their small, sharp dewclaws are also in contact with the ground as they walk, giving them even more insurance against slipping. Their wool has an outer layer of hollow guard hairs and an inner coat of dense fine hair, very much like the fur of polar bears, and can protect them from winter temperatures as low as -50C (-58F)!
#mountaingoat #glacierbaynationalpark #adaptation #lindbladexpeditions #natgeotravel


David Cothran

Jimmy White heads out for polar bear guard duty on a huge expanse of fast ice in Hornsund, at the south end of Spitsbergen in Svalbard. Behind him is the National Geographic Orion, garaged at the edge of the ice. It takes a very sharp eye to spot a pale cream-colored bear somewhere out in all that white wilderness, particularly if one might swim up onto the ice behind you at any minute. I went and had a look off the stern right after I shot this image, just to check. Sometimes no polar bears is exactly what you want to see!
#svalbard #arctic #ice #lindbladexpeditions #natgeotravel


David Cothran

Sunset on the Nile, a little downstream from Luxor. The Nile is commonly regarded as the longest river in the world, but it’s exact source remains controversial and the Amazon runs it a close race. In any case, the river is over 4,000 miles long and particularly impressive because for much of its length north of Lake Victoria it runs through the easternmost parts of the Sahara. This narrow ribbon of green through the desert that has nourished wildlife, guided migratory birds and supported one of the world’s greatest early civilizations for many thousands of years.
#egypt #nile #sunsetreflection #lindbladexpeditions #natgeotravel