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Canberra-based naturalist, conservationist, educator since 1980. I’m passionate about the natural world (especially the southern hemisphere), and trying to understand it and to share such understandings. To that aim I’ve written several books (most recently 'Birds in Their Habitats' and 'Australian Bird Names; origins and meanings'), run tours all over Australia, and for the last decade to South America, done a lot of ABC radio work, chaired a government environmental advisory committee and taught many adult education classes – and of course presented this blog, since 2012. I am the recipient of the Australian Natural History Medallion, the Australian Plants Award and most recently a Medal of the Order of Australia for ‘services to conservation and the environment’. I live happily in suburban Duffy with my partner Louise surrounded by a dense native garden and lots of birds.

Thursday 12 December 2013

Genovesa: Tower of the Galápagos. Part 2.

Last time I found that there was more rhapsodising to do about wonderful Genovesa than I could politely fit into one posting, so I desisted after talking about some of the seabird treats, leaving its other wonders for another day. That day is here.

It's probably fair to say that most of us wouldn't make the considerable journey there just to admire the vegetation and landscapes, though the arid environments of the Galapagos, sun-baked and often growing out of pure lava, are in themselves fascinating and rapidly become compelling. Unexpected combinations of organisms, penguins and tropicbirds for instance, are the norm for the Galapagos, but I find cactus alongside mangroves to be equally wondrous.
Prickly Pear cactus Opuntia spp. juxtaposed to Red Mangrove Rhizophora mangle. I can understand why the Swallow-tailed Gulls find it perfectly normal, but I'm delighted by the concept.

The mangroves don't follow the cactus inland - even in the Enchanted Isles, as the Galapagos were once known! - but here the tough deciduous Palo Santo is prevalent.
Low tangled Palo Santo-dominated forest, Bursera graveolens Family Burseraceae.
As is true pretty much anywhere in the archipelago you are likely to be greeted ashore by lounging Galapagos Sea Lions Zalophus wollebaeki.
Sleeping Galapagos Sea Lion, Darwin Bay landing, Genovesa.
This species is confined to the Galapagos, except for a small colony on Isla de la Plata, closer to the mainland.
Also relatively easy to see on Genovesa is the much less commonly seen Galapagos Fur Seal Arctocephalus galapagoensis, the smallest of the sea lion/fur seal family Otariidae.

Adult male Galapagos Fur Seal.
While often regarded as rare, this species is actually almost as numerous as the sea lions, but is far less frequently encountered. One reason, oddly, is its thick fur, which led to heavy exploitation and a population crash in earlier years. This insulation means that it cannot safely lie out in the sun on beaches, or crowd together as the sea lions do.
Instead individuals climb nimbly onto cliff faces and retreat into shady niches when not at sea. They go out to hunt at night, unlike sea lions, so are rarely encountered from boats either.
After the sea lions, one of the first animals likely to greet you is the Sharp-beaked Ground Finch Geospiza difficilis. Genovesa is the only place they are readily found; elsewhere, on Santiago and Fernandina, they are mostly only in the remote high country. On the far more isolated and harsh islands of Darwin and Wolf (far to the north-west of the map in the previous posting) this little insectivore has gained a notoriety as 'the Vampire Finch', for its ingenious habit of pecking nesting boobies to collect blood in a water-pauperate world.
Sharp-beaked Ground Finch, inordinately naive, like other Genovesans.
Another hard to see 'finch' (see here for explanation of this equivocation) which is easy to see on Genovesa is the Large Cactus Finch Geospiza conirostris, found only on remote islands - here, Espanola in the far south-east, and the out-of-bounds Wolf and Darwin.

Large Cactus Finch female, Genovesa.
The Marine Iguanas of Genovesa are tiny compared with other sub-species; the largest males here weigh scarcely a kilogram, compared with a massive 12kg maximum in southern Isabela.
Marine Iguanas, clustering for warmth in the late afternoon sun.
Apparently bare sand can suddenly be seen to be swarming with little Fiddler Crabs, which just as rapidly vanish again into their burrows when disturbed.
I think these are probably Uca galapagensis, but I can't find any record of them occurring on Genovesa.
Advice welcomed!
On the east side of Darwin's Bay, up the cliffs via the steps known as El Barranco, a track leads to a vast creviced lava field, where some 200,000 pairs of Galapagos Storm-petrels nest.
Unfortunately the storm-petrels had just left when we were there, but this is their nesting ground.
Someone who regretted the end of the nesting even more than me was this Short-eared Owl Asio flammeus, who regards the breeding storm-petrels as a vast smorgasbord.
Roosting Short-eared Owl, Genovesa. This species is found throughout much of the world.
As a result, the delightful Galapagos Doves Zenaida galapagoensis are now finding life more difficult, as the owls' attention turns to them, and until next storm-petrel breeding season they will be a lot warier than they were on this day.
Galapagos Dove, almost underfoot, Genovesa.
Genovesa is a special place in a special archipelago (and in a world that despite all, is still special too). Try and include it in your dream trip, and maybe one day even a real one!

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