Isabela island, the Galápagos

August 16, 2023 • 9:30 am

On Monday evening we took a Zodiac cruise along the coast of Isabela Island (below), a large member of the archipelago. We couldn’t land there because of the cliffs, but there was plenty of wildlife on the steep lava rock.

Here’s Isabela, on the left, produced by the joining of six shield volcanoes. Its top is shaped like a seahorse. Wikipedia says this:

Isabela Island (Spanish: Isla Isabela) is the largest of the Galápagos Islands, with an area of 4,586 km2 (1,771 sq mi) and a length of 100 km (62 mi). By itself, it is larger than all the other islands in the chain combined and it has a little under 2000 permanent inhabitants. The island straddles the equator.

We’ve now crossed the equator three times (there was a celebration Monday night) but we’ll cross it three more times. I hope to be on the bridge the next time we cross so I can photograph the 0.0000 degree latitude.

It was hard photographing animals on the cliff from a bobbing Zodiac;  the shutter speed was about 1/30 or 1/60, and I had to wait for a moment of stillness to snap the shutter. The photos I show are culled from a bunch of blurry ones.

A collocation of marine iguanas. I don’t know how they get up these near vertical cliffs, but they do. (We still need a word for a group of marine iguanas!)

More. This is a near vertical surface, but they hang out on the ledges.

A new endemic species for this trip: the Nazca booby (related to the blue-footed booby).

And two views of a native but non-endemic species, the brown noddy.

And of course our famous flightless cormorant, another endemic species. Look at those pathetic wings!

Another view. Those wings aren’t getting anybody off the ground.

A new endemic mammal for me: the Galápagos fur seal. (Photographed at a great distance.) It has external ears, so it should be the Galápagos fur sea lion.

This is what a full Zodiac looks like. They generally hold twelve people plus the driver and the naturalist.

Dinner Monday night. Caesar salad to start.

Steak (rare, of course) with red peppercorns, rice, and asparagus:

And “Ecuadorian lime pie” with meringue. It was a light dinner for me, which is what I wanted.

Yesterday we landed in Urbina Bay on Isabela, an area formed only in 1955 when tectonic movement uplifted a large section of the seabed almost instantly, stranding sea life and leaving huge chunks of coral aboveground. Here’s a huge hunk of coral stranded almost 70 years ago

The skull of a giant tortoise. Our naturalist estimated that it would have been about a century old: a youngster

And the skeleton of a different giant tortoise. It still has the scutes, or pieces of hard skin that grow over the shell. It must have died recently, perhaps of disease.

The trail went by many burrows, which are the refuges of the land iguanas that they dig out themselves.

And, lo and behold, here’s one of these monster lizards. Darwin found them ugly and had nothing good to say about them in the Voyage of the Beagle,  but he was anthropomorphizing. They are remarkable animals.

A close up of the head of one of the three land iguanas in the archipelago, the Galápagos land iguana, a widespread species on the archipelago. There are two other species, the Galápagos pink land iguana, found on Isabela island, and Santa Fe land iguana from the eponymous island.

We finally ran into the species we were hoping to see, sitting right in the middle of the trail: a Galápagos giant tortoise, one of the dome-shelled variety (there are also “saddle-back morphs with an indentation in front of the shell to help them reach higher vegetation and cacti.

Some consider the different populations to be different species, usually 11, while others consider the different populations to be subspecies of a single species. (Some islands have more than one type.) This is a judgement call, as the different forms, when in captivity, can produce viable and fertile hybrids. But that’s in captivity, not in the wild. For the moment I’ll consider them subspecies, as their reproductive behavior, at least in captivity, doesn’t indicate any problems with crossing of the different forms. (That’s not a great way to judge,bthough, as species that maintain their distinctness in the wild where they cohabit can nevertheless produce fertile hybrids in the confinement of zoos, like the lion and tiger, which once lived in the same areas of India.)

A head shot.  This guy is at least a century old:

The rear leg. Cowboy boots are made from this skin, and you can recognize them by the polygonal scales (alligator and croc have square scales). It is illegal to sell sea turtle boots as the species are endangered, and if you see them on eBay, often duplicitously advertised as “sea alligator boots” or “exotic reptile boots,” report them.

Note the blunt claws, used for digging holes to lay eggs.

Two endemic flowering plants. This one is Cordia lutea, also known as yellow cordia or, in Spanish, muyuyo. 

And the other endemic, “Darwin’s cotton” (Gossypium darwinii), in the same genus as the regular cotton plant, but fiber cottons are diploid while this is one of five tetraploid species in the genus.

More tomorrow.

17 thoughts on “Isabela island, the Galápagos

  1. Magnificent!

    The toe shape also looks like a shape that would not harm eggs – the toes are a fascinating insight in plain view, thank you!

  2. I nominate “kaiju” as the term for a large gathering of marine iguanas.

    I wonder if they ever lose anyone overboard on those Zodiacs.

    1. I’m sure they do occasionally – hence the life jackets – especially if people stand up and are looking through their cameras (though other passengers usually grab anyone who looks like they are about to topple). When I was learning to drive a much smaller inflatable Achilles, my boss challenged me to try to throw him out of the boat with rough maneuvers and I couldn’t do it despite fast hard turns, blasting through surf, etc. He was holding on of course. I personally never had anyone go overboard unintentionally. I do know folks who have flipped entire small Achilles in nasty surf and high winds but that is very unlikely with large, heavily loaded Zodiacs (and they wouldn’t go out in nasty sea conditions anyway).

      1. I once spent some time having fun with a tiny little Sea-Doo sport boat. It had twin Rotax engines and could go from 0 to 50 in a seeming instant and turn on a dime. The only time I saw someone go overboard (not me driving!) was attempting to get the boat out of Sebastian inlet in particularly rough conditions. I was nearby on a Waverunner and picked the person up, which was pretty tricky in the conditions. I had to maintain some headway in order to keep from being rolled over as they where attempting to board. Wouldn’t have been possible with a propeller.

  3. Thank you so much for sharing the sights on your Galapagos tour. absoultely amazing! I wish I could be there.

  4. I follow your blog because of some South America posts. Then I also found some with New Zealand. I’ve also traveled a lot, I didn’t benefit from National Geographic, but for the Galapagos trip I envy you a little.

  5. Tortoise sighting!!! Thanks for the great close-ups. All the photos were terrific; another successful outing.

    And fun fact: pink peppercorns aren’t actually peppercorns, but the berries of the Brazilian Pepper tree. The fruit is more closely related to a cashew than an actual peppercorn.

  6. Doubt you’re going to get anyone to change the common name ‘fur seals’ (even though they aren’t true seals or phocids) into ‘fur sea lions’ at this point, even if it might be more accurate or instructive (but you never know, jellyfish have become sea jellies). (Aside for geeks: what makes this suggested name change perhaps more accurate or instructive is not only that the fur seals are otariids, but also that northern fur seals (Callorhinus) and the many species of southern fur seals (Arctocephalus) may well not be a clade. The southern fur seals may be more closely related to the southern sea lion species (no, not the Galapagos Sea Lion) than they are to Callorhinus. Convergent evolution anyone? The pesky genome folks are messing things up again trying to find the truth. I’ll wait a bit to see. When I started out they were still going back and forth about whether pinnipeds as a whole were mono-, di- or even tri-phyletic. Everyone now agrees – monophyletic) In any case ‘fur seals’ (though maybe not a clade but rather convergent) and sea lions, are different. Fur seals use underfur for insulation (like a sea otter, and what they were hunted for) while sea lions are mostly blubber insulated. There are some other general differences between ‘fur seals’ and ‘sea lions’. Fur seals are generally smaller overall, exhibit greater sexual dimorphism (though it is pronounced in both), have longer flippers relative to their body size and shorter but pointy noses.

  7. Thank you for your lovely photos and trip descriptions! I must confess I am jealous; however, I’d never get into one of those inflatable things. Just looking at them scares me.

    Are any multilegged creatures native to the Galapagos, IOW, critters with more than 4 legs? Just curious.

  8. Belatedly, glad you’re seeing so much more of Galapagos than I did. Those are Black Noddy, not Brown; body color differs, and the white cap is more sharply bordered at rear of head.
    Doug Futuyma

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