Monday, January 28, 2013

The Birds!

Maybe it’s the release of the Hitchcock movie, but I’ve had birds on my mind, and have spent some time looking at the analysis of Seven Site avian remains done last year by Sara Collins of Pacific Consulting Services, Inc. in Hawaii (Collins 2011). Some basics:

• 2433 bird bones recovered and analyzed.

• Overwhelming majority are Red-footed Booby (Sula sula) and Lesser Frigatebird (Frigata Ariel).

• Most are adult, a few juvenile

In preparing the bird and fish bones for analysis, I divided the site into eight “clusters” based on geography and the gross distribution of faunal remains. Each cluster represented either a very distinct part of the site (e.g. the 2001 M-units, way off at the NW end), or some sort of concentration of faunal remains, often associated with more or less distinct features (e.g. fire sites, concentrations of shellfish). Seven of these clusters – designated 2, 3, 4, 5, 6, X, and BB – produced bird bones.

Clusters 2 and 3, along the ridge crest in the vicinity of the Big Buka and the fire features excavated in 2001, each contained remains that could be accounted for by the consumption of four boobies and one to two Frigatebirds, but since these clusters were adjacent to one another, it is quite possible that they collectively contain the remains of only four boobies and two Frigatebirds. Cluster 4, containing the WR Feature (containing the partly melted bottles, snap, ferrous items, and probable rouge fragments) also produced the remains of about 4 boobies and two Frigates. Cluster 5, situated between the WR Feature and the immediate neighborhood of the SL Feature (probable rouge, ferrous, bottles, etc.) produced the remains of perhaps one boobie. Cluster X, where most of the jackknife was found, produced the remains of 2 boobies, and Cluster BB – a surface birdbone scatter downslope from the SL Feature – produced bones from 2 boobies and 8 Frigates.

And then there’s Cluster 6, around the SL Feature.

Cluster 6 produced evidence of at least 22 boobies and 6 Frigates, along with one each of Phaeton lepturus and Phaeton rubricaudai, the white-tailed and red-tailed Tropicbird. Many of the bones are charred. Someone processed and cooked a lot of birds around the SL Feature.

As far as we know, four “populations” may have killed and processed birds at the Seven Site:

1. The colonists; we have oral accounts of bird-hunting at the site;

2. Gallagher, who we know from historical data and oral accounts spent time at the site;

3. The Coast Guardsmen, who we know from photographic, oral, and archaeological evidence hunted birds around the site; and

4. The castaway(s).

We have no particular reason to think that Gallagher spent much time at his Seven Site “camp,” or that he or others processed birds while there. As far as we know the Coast Guardsmen shot birds, but did not process or eat them. They might have hauled a particularly impressive bird back to the station for display purposes, but most times probably discarded carcasses on site – where they would almost certainly be quickly consumed by crabs.

The colonists apparently sometimes cooked and ate birds while visiting the site to hunt turtles, but most often – according to oral testimony – did preliminary processing at the site and then took the carcasses back to the village. Preliminary processing involved chopping off the wings, probably removing the heads and gutting the bodies, and skinning the birds, removing the feet in the process. So a deposit of bird bones left by the colonists should include a disproportionate number of wing bones relative to bones of the thorax.

Some of the clusters do have more wing bones than bones of the thorax. Cluster 2, for instance, on the ridge near the Big Buka, produced 11 boobie wing bones to only 5 bones of the thorax, and 4 leg bones. But it produced more thoraxial Frigatebird bones (4) than wing ones (2), along with two cranium fragments. Cluster BB – as noted, a surface scatter downslope from the SL Feature – shows what may be a more expectable profile for a colonist-produced birdbone concentration: 50 Frigatebird wing bones and only one bone from a Frigatebird’s thorax region. BB also produced 3 boobie wing bones and 2 thoraxial bones; I suspect that these kinds of quantities could be found virtually anywhere on the site, reflecting natural distribution of bones by crabs and other factors.

Cluster 4, around the WR feature, produced 5 boobie wing bones and 10 bones of the boobie thorax, together with 4 Frigate wing bones and 7 bones of the thorax. This looks more like the remains of someone’s on-site meals than like food procurement for the colonial village.

And Cluster 6, around the SL feature, produced 60 boobie wing bones to 68 thoraxial bones and 61 leg bones, together with 52 Frigate wing bones to 13 from the thorax and 2 from the legs. There were also 2 boobie and 3 Frigate cranial fragments. This, too, looks a lot more like on-site consumption than like procurement for the village.

So, someone appears to have eaten about 30 birds – 22 boobies, 6 Frigatebirds, and 2 Tropicbirds – at and around the SL Feature, which has produced a considerable diversity of possible castaway artifacts. If the eater was the castaway, what does this tell us about him or her?

Boobies are pretty easy to catch; they lay eggs on the ground and sit on them till they hatch, the male and female taking turns. They roost in trees, but also in low bushes and sometimes on the ground. Frigatebirds usually roost in trees, but when they do land on the ground, their very small feet make it difficult for them to get around. Even a castaway unskilled in bird procurement would probably not have a hard time catching a bird or two each day in the vicinity of the Seven Site. Birds would probably be much easier to catch than fish; fish dart around the tidepools and are inherently slippery, but boobies, particularly when nesting and at least until they become wise to the ways of humans, often just sit under bushes and wait to have their necks wrung.

Former colonists on Howland, Baker, and Jarvis Islands (both Native Hawaiian and Anglo) interviewed for the video Under a Jarvis Moon (See ) said that boobies were quite tasty, while Frigatebirds tasted terrible and had little meat. This might account for the much larger number of boobies represented in the Cluster 6 collection, though one wonders why there are even six Frigatebirds.

Setting aside the question of the Frigatebirds, it is easy enough to imagine a scenario in which the castaway(s), arriving at the Seven Site, found a large number of boobies nesting on the ground, ready to be harvested. They would be particularly vulnerable to harvesting if they were sitting on eggs, which they do not abandon readily. According to the Howland/Baker/Jarvis colonists, boobie eggs are quite tasty.

A source cited by Collins (Child 1960) suggests that boobies in the Phoenix Islands fledge (that is, the parents nest, the fledgelings hatch and grow to the point of independence) mostly between April and December, though a more recent study (Gupta 2007) indicates only that those in a given population fledge synchronously (all at more or less the same time), throughout the year but varying by location. We have observed boobies sitting on eggs, and fledging, in late May and early June.

It is not implausible, then, that the large collection of boobie remains in and around the SL Feature represents occupation of the site for a fairly extended period of time (or by a large number of people, for which there is no other evidence), most likely between April and December. The relative dearth of fledgling bones suggests that the feature was in use prior to the actual birth of baby boobies. Exactly when this would be requires further research, but if we simply take the earlier part of the fledging season recorded by Child (1960), the feature would have most likely have been in use between April and August.

A single boobie would probably make a good meal for one or two people, so we might propose as a rough estimate that the boobie bones indicate use of the SL Feature for at least ten days or so by two people, or twenty-plus days by one person. Boobie meat might become pretty boring after a few days, but there is plenty of evidence at the Seven Site for the exploitation of other food sources – fish, shellfish, baby sea turtle, adult sea turtle. But particularly in the nesting/fledging season, boobies would have provided a fairly reliable food source when others failed, or when others were too difficult to procure.

If we assume – and this is, of course, pure conjecture – that the SL Feature was used by a single castaway, who was responsible for all the bird bones as well as the nearby fish, shellfish, and baby turtle remains, then we are surely looking at occupation at the site for a period of at least a month or so.


Child, Peter

          1960 Birds of the Gilbert and Ellice Islands Colony. Atoll Research Bulletin #74, Pacific Sciences Board, National Academy of Sciences-National Research Council, Washington DC.

Collins, Sara

          2011 Analysis of TIGHAR Faunal Materials. Manuscript, TIGHAR files.

Gupta, Anuradha

          2007 Proposed Important Bird Areas (IBAs) in Kiribati. Prepared for Birdlife International Pacific Partnership, Suva, Fiji.