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Easter Island as a non-native bird sanctuary

Discussion in 'Speculative Zoo Design and Planning' started by Cassidy Casuar, 7 Sep 2019.

  1. Cassidy Casuar

    Cassidy Casuar Well-Known Member Premium Member 5+ year member

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    Easter Island is currently the closest existing thing to a location on earth where non-native species can be introduced without negative consequences for native animals. The only remaining endemic animals are very small invertebrates, and the only native bird species that still breeds on the main island is the red-tailed tropicbird (Phaeton rubricauda). There are currently five species of introduced birds on the island (excluding domestic chickens); Chilean tinamou (Nothoprocta perdicaria), chimango caracara (Phalcoboenus chimango), feral pigeon (Columba livia), common diuca finch (Diuca diuca), and house sparrow (Passer domesticus).

    In my fantasy, the island would have several other non-native bird species be introduced to it, and these species would be able to form wild populations on the island. I have selected the species that would be introduced to the island in my fantasy based on the following criteria:
    -They cannot be strongly predatory of other birds.
    -They cannot be strongly piscivorous (this would make them likely to compete with both the tropicbird, and the several other seabird species that nest on the Motu islets).
    -They cannot be prone to rapid population decreases due to rat predation (Pacific rats and brown rats are still abundant on the island).
    -They must be unlikely or unable to fly to nearby landmasses with close relatives, where they could out-compete these relatives, or hybridise with them, to the point of extinction.
    -They must be unlikely or unable to produce fertile hybrids with the other birds on the island.

    Most of these birds would probably only be able to sustain themselves following more reforestation of the island. Most of the island is covered by a meadow, and the largest stand of trees on the island is a eucalyptus plantation. I am aware that the successful introduction of any of the species in my fantasy also makes several assumptions. These include that the island's residents will not hunt any of these species to extirpation prior to them becoming established, that the novel species will not quickly die out due to transmitting fatal diseases to each other, and that none of the novel species will reverse the revegetation of the island. If these assumptions all turn out to become a reality, then these are the introduced birds that would be established on Easter Island in the future, in my fantasy:

    -Eurasian jackdaw (Corvus monedula spermologus)
    -Black-throated magpie-jay (Cyanocorax colliei)
    -Red-cowled cardinal (Paroaria dominicana)
    -Taiwan hwamei (Garrulax taewanus)
    -Red-browed finch (Neochmia temporalis temporalis)
    -European goldfinch (Carduelis carduelis britannica)
    -Bronze mannikin (Spermestes cucullata scutata)
    -White-fronted chat (Epthianura albifrons)
    -Plumbeous rail (Pardirallus sanguinolentus landbecki)
    -Yellow-necked francolin (Pternistis leucoscepus)
    -Domestic guineafowl (Numida meleagris galeatus)

    In addition to these self-sustaining birds, my fantasy also involves the creation of a feeding station for several parrot species that would be present at the Tau Kiani Botanical Garden. The parrot species would be semi-domestic in the way that they would be fed at the Garden, but would otherwise have free roam of the island. At least three breeding pairs of each parrot species would be introduced initially. As there are no trees on the island that are big and old enough to have holes that would be suitable as nest cavities, there would instead be nest boxes for the parrots that would be nailed to specifically-marked trees in the eucalyptus plantation. A veterinary facility would also be constructed at the Garden, specifically for the parrots. The parrot species that would be introduced would be the following:

    -Blue-and-yellow macaw (Ara ararauna)
    -Timneh parrot (Psittacus timneh)
    -Citron-crested cockatoo (Cacatua sulphurea citrinocristata)
    -Red-fan parrot (Deroptyus accipitrinus accipitrinus)
    -Alexandrine parakeet (Psittacula eupatria nipalensis)
     
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  2. Ebirah766

    Ebirah766 Well-Known Member 5+ year member

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    The endemic invertebrates have to be protected though. It's not like we can just brush them off.
     
  3. birdsandbats

    birdsandbats Well-Known Member 5+ year member

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    I really like this idea, and would love to see in real life, although I agree it can't happen unless there is somewhere for the endemic vertebrates to go. Are there any small, offshore islands?
     
  4. Daktari JG

    Daktari JG Well-Known Member 10+ year member

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    The remaining insects aren't doing so well it seems
    Extinction Looms for Easter Island's Only Remaining Native Species - The Crux

    the birds that were extinctified were
    a crake
    a rail
    2 parrots
    a heron
    and the barn owl

    If such a plan were pursued I would suggest eradicating the rats and the pigeon as a first step
    and then replacement with closely related but endangered species from the Pacific
    for example Guam Rail and Tahitian Lory
     
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  5. Cassidy Casuar

    Cassidy Casuar Well-Known Member Premium Member 5+ year member

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    The rail probably wouldn't last long, because it is a ground-nesting species that evolved in an environment without mammalian predators, and in addition to rats, there are also many free-roaming dogs on Easter Island. There are also cats, but I'm not sure how common they are there. The idea of regulating the number of predatory pets would probably be very difficult to introduce to the people of an island that doesn't have any endemic vertebrates left.
     
    Last edited: 11 Sep 2019
  6. Cassidy Casuar

    Cassidy Casuar Well-Known Member Premium Member 5+ year member

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    Only the Motu islets, which don't have any vegetation on them, to my understanding.
    Forming insurance populations of the invertebrates in captivity would be required prior to introducing any new bird species. Some of the invertebrates would be easier to breed than others, though. Have endangered mites been bred in captivity before?
     
  7. Ebirah766

    Ebirah766 Well-Known Member 5+ year member

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    Mites eat bodily fluids right? If so, you could simply provide raw meat for them to snack on.
     
  8. Kakapo

    Kakapo Well-Known Member

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    This is like saying "Vertebrates eat grasses not? Then you can fed them with spinach juice."

    I doubt that raw meat could serve as food for more than 5% of the species of mites in the world. A group whose diversity of species is almost as big as vertebrates (for sure bigger if we count with the undescribed species), and the diversity of feeding habits is probably bigger than for vertebrates.
     
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  9. Cassidy Casuar

    Cassidy Casuar Well-Known Member Premium Member 5+ year member

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    The mite species that I mentioned were discovered in the vegetation surrounding one of the crater lakes. So, no; raw meat probably isn't a part of their diet.
     
  10. Ebirah766

    Ebirah766 Well-Known Member 5+ year member

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    ah, so do some studying of their diets and collect what they eat. do we know what they eat?
     
  11. Cassidy Casuar

    Cassidy Casuar Well-Known Member Premium Member 5+ year member

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    Unlikely. Even the diets of Easter Island's better-known invertebrates have not been formally researched.
     
  12. Cassidy Casuar

    Cassidy Casuar Well-Known Member Premium Member 5+ year member

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    I was wrong about there being no endemic animals left on the island apart from invertebrates. The skink Cryptoblepharus poecilopleurus paschalis is endemic to Easter Island. That doesn't necessarily mean that it is native; it could be a non-native subspecies like the St Kilda field mouse, but I cannot find anything which confirms or denies that.