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As a kid, I read James and the Giant Peach by Roald Dahl (along with a few of his other works).  For those who haven’t read it, may I suggest the plot summary on Wikipedia as a decent place to start?

For a variety of reasons, gulls have been maligned (in science and literature) as dirty, scavenging, pests.  But they’re also a heck of a lot of fun to study.  During my PhD, a fellow grad student needed to catch gulls during the winter.  Newfoundland (and St. John’s in particular) is known among birdwatchers as THE destination for gulls.  In an average winter, one could see 10-14 species, depending on the conditions, and how long one stayed around.

Alex with a Glaucous Gull

Catching and banding a Glaucous Gull at the Robin Hood Bay Waste Management Facility in St. John’s, NL. January 2010.

I don’t think my fascination with gulls came from the passage in James and the Giant Peach where 500 seagulls are harnessed to the peach by spider webs, and carry the peach across the Atlantic, away from marauding sharks (another maligned taxon).

Sure, this is children’s fiction, but recently, a group of physics students at Leicester University decided to look into itCould 500 gulls lift a giant peach of the dimensions provided by Dahl?  Well, it turns out the answer is … no.  500 are nowhere near enough.  In fact, the physicists calculated that it would take 2,425,907 Common Gulls (or Mew Gulls, Larus canus – one of the smaller, but for possibly obvious reasons, common species in the UK) to lift the peach.

According to the Joint Nature Conservation Commission, during the “Seabird 2000” monitoring program (1998-2002), there were a total of 1059 breeding pairs in Ireland, about 50 pairs in England, a further 557 pairs in Northern Ireland, and 48,602 breeding pairs in Scotland.  That’s a total of 49,728 pairs, or 99,456 individuals.  Throw in another 50% for non-breeders (young or old birds, or those who skipped breeding in a given year), and we get about 150,000 birds.  That’s well short of the 2.5 million required.

Gulls nest in mixed colonies, so let’s consider that four breeding species also came to help:

Species Herring Gull (Larus argentatus) Lesser Black-backed Gull (Larus fuscus) Great Black-backed Gull (Larus marinus) Black-headed Gull (Chroicocephalus ridibundus)
Ireland

5247

2875

2189

3876

Northern Ireland

714

1973

76

10,106

England

56,837

66,028

2191

82,730

Wales

13,974

20,772

427

1986

Scotland

72,097

25,042

14,733

43,173

Total

148,869

116,640

19,616

141,871

These are breeding pairs, so using the same logic above, we get 446,607 Herring Gulls, 349,920 Lesser Black-backed Gulls, 58,848 Great Black-backed Gulls, and 425,613 Black-headed Gulls.  When we add in the aforementioned Common Gulls, that’s 1,430,712 gulls.  Now, this all assumes that populations of these species have remained constant between James’ peach adventure, and the Seabird 2000 census, but we’re still about a million gulls short.  Perhaps some popped over from France or Spain?  Norway also has large gull populations, as do most other Baltic nations.

The other thing to consider is that, with the exception of Black-headed Gulls, the other species are larger than the Common Gulls used in the Leicester University study.  Great Black-backed Gulls, at 1.5-2.0 kg, are the largest gull in the world.  So they could probably lift a greater mass, and James would then require fewer gulls than the 2.5 million.

What about other fiction accounts of ecological activities? Could the Earthworm, Centipede, Old Green Grasshopper, Ladybug, Spider, Glowworm and Silkworm be a viable ecological community?  To say nothing of gigantism among the genus Prunus

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