Sunday, September 24, 2006

 

A Pound of Fish

My son had said before our leaving on this trip that he would be thrilled to see anything, whatever happened to come our way--after all, this was an expedition, not a museum, and there were no guarantees--with only one specific request. He really hoped that this would be his chance to see a frigate bird. Frigate birds are common enough on the Galapagos; however, my son wanted to see not just any frigate, but one with his bright red throat sac wobbling at full inflation. Male frigates swell their throat sacs as a mating display. I wasn't sure how much influence I was going to be able to have over this.

Fortunately, mating turns out to be a year-round proposition for many animals in the Galapagos, frigate birds included. The weather changes so little between seasons and the environment is so unforgiving that most creatures take an opportunistic view of things. When food is plentiful, some of them will happily mate several times in a year.

There are two species of frigates on the Galapagos, the Greater Frigate and the Magnificent Frigate, but they look and act similarly enough that the distinction, while I am sure it is important, is largely lost on me.

Frigates are spectacular gliders that hang in the air like shadows. There are other beautiful flyers in the Galapagos, particularly the exquisite tropic bird, but you can always feel the athletic force pushing their swoops and dives, while frigates hardly seem to move their bodies. They hang; they turn, slowly, through the sky. And then they tilt their notched shapes, only a slight shift--and have in that instant already flicked through a hundred yards and whipped past some thumping booby huffing along. It was only later, when I watched a booby fly by itself and realized how elegant and efficient it is, that I started to understand how beautifully a frigate bird navigates through the air.

Sometimes frigates also knock slower birds on the head to force them to vomit up their last meal, which the frigate then swallows in flight. This maneuver, called "kleptoparasitism," has earned them the nicknames man o' war bird and pirate bird--and no doubt others.

They are not small animals, more or less goose-sized (the Greater Frigate seems to be, as one might expect, somewhat larger), which makes their buoyancy in the air all the more startling. To keep their bodies so light, frigates' bones are as thin as drink-straws and their feathers, unlike those of most fisher-birds, are dry and fluffy rather than oiled and sleek.

Their nests start out functional although not particularly lovely and quickly degenerate, torn apart by their movements and caked in their excrement. Frigates will use almost anything as building materials. I saw a frigate squatting in a nest woven out of a tangle of bones, as if birds had their ogres too.

Frigates can barely walk--unlike sea lions, who are ungainly but effective on land, frigates are ungainly and helpless--and cannot swim at all. Although fish make up almost all of their diet, frigates are limited to scooping them from the surface of the water or, as mentioned before, knocking them out of other birds' gullets. That they cannot swim is not the only problem. They need at least a short drop in order to glide into the air, and so they cannot take off from the surface of the water. Also, their dry, unoiled feathers are not waterproof, so if a frigate is sprayed by even a few droplets, he will plunge into the sea and die. The odds seem very bad; but I saw many frigates fishing, and I saw none fall.

Wednesday, September 13, 2006

 

Marine Iguana Pile-Up

There aren't just a lot of unusual animals in the Galapagos and an amazing variety of them; they also appear in startling numbers. Vast stretches of sand will be covered by the torpedo shapes of sleeping sea lions. The low, scrubby palo santo forests can contain more boobies and albatrosses than trees. Whole rock faces are colonized by marine iguanas, their black hides distinguished from the lava only by the squiggling grey line of the ridge that runs down their backs.

(Play find the iguana!)

This is an anecdote about a small huddle of marine iguanas on EspaƱola Island (aka Hood Island, if you happen to know the older English names). Here they are, dozing happily. Although the sunlight is intense in the Galapagos, which straddle the equator, it is not particularly warm. Marine iguanas are cold-blooded creatures that feed almost exclusively on sea algae, and spending so much time in the cool water means they have to spend that much more time warming up again. This is probably one reason they end up resting in groups; each of them is looking for an optimally warm spot with good sunshine, and there are only so many of those spots to be found.

Sea lions, however, choose their company before their location and seem to have more clearly social goals in mind when they group.

Unfortunately I had run out of shots on my camera when one young female sea lion (about the size of those here) decided that she would bridge the gap and try socializing sea lion-style with marine iguanas.

She heaved her body along the sand, coming at what is a full gallop for a sea lion. It is an awkward, side-to-side motion that you can easily demonstrate for yourself by dropping onto your stomach, leaving your legs inert, and propelling yourself forward one arm-thrust at a time. It can move a sea lion surprisingly fast on land, although graceful it is not.

She announced her intentions with the "eghhhkkk, eghhhkkk, eghhhkkk" grunt that appears to mean, "pay attention to me!" The marine iguanas perhaps had never given much thought to what different sea lion calls mean, and perhaps simply didn't care. They remained dozing in the sun.

"Eghhhkkk, eghhhkkk, eghhhkkk!" Closer.

Indifference.

"Eghhhkkk, eghhhkkk, eghhhkkk!" Almost there. The iguanas weren't noticing her, and she wasn't slowing down.

Then she reached the edge, and this is when I learned that marine iguanas can move pretty quickly too when they have to. There was an iguana directly in her path--and then suddenly there wasn't. He launched himself into the air, his hind legs spinning frantically, leaped over some of his companions, and scrambled over the rest. All of whom still remained sleeping.

The chatty sea lion was startled by the iguana flying past her face into stopping for a moment, but not much longer than that. She yapped out her call again, testing. The iguanas still didn't reply. Evidently she took this to mean that she wasn't trying hard enough. She restarted the non-stop "eghhhkkk"s and flump-waddled around the iguana perimeter.

Unfortunately, she cut it too close to one iguana who must have been lost in his dreams, because he got stepped on. Even a small female sea lion weighs a lot and is a good fifteen times the size of even a large marine iguana.

The insulted iguana reared up, abruptly very awake, pushing his head and shoulders into the air. At first I was afraid he'd been hurt. But when the sea lion shifted to the side slightly and plopped down on her side, contentedly joining the group at last, the iguana didn't move or otherwise seem distressed.

But he was outraged indeed.

Everyone else around him was sleeping. There was no one to see what he did, unless he regarded the humans waiting on his beach with more interest than I sensed. And yet he did not go back to sleep. He was outraged, and this must be expressed. An utterly wrong thing had happened. Perhaps there was nothing he could do about it. Marine iguanas are mild-mannered herbivores who simply do not think of striking other creatures, and the sea lion snoozing next to him was far too big for him to push aside. Perhaps no one else would ever know about this ill-mannered act. The other iguanas, who had not been disturbed, had found no reason to look up from their own rest.

But he was outraged, and nothing could take that away from him. So he held his outraged pose, although he was alone in it.

He was outraged still when we left ten minutes later, and I don't know how much longer he persisted. But somehow I suspect that an iguana's sense of propriety is not easily restored and that their moods are enduring.

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