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Friday, May 22, 2015

Marianas Avifauna Conservation

On Guam, the damage has been done.  The accidental introduction of the brown tree snake to the island has resulted in the extinction or extirpation of many of the island's bird species, the severe decline of many others.  Efforts to reduce the numbers of the snake are in place, but the main focus since has been to limit the spread of the snake.  The realization has been that what has happened on Guam could happen elsewhere.

But what do to about the survivors?  The Guam rail, the Micronesian kingfisher, and other birds which now survive in zoos and breeding centers - what about them?  Maintain them in captivity forever, and if so, to what end?  Reintroduce them to Guam?  You might as well pluck them first so the snakes will have an easier time swallowing them.  Recently, a consortium of government agencies, NGOs, and zoos has come up with another option - the Marianas Avifauna Conservation Project.

The premise of the MAC project is simple.  There are lots of islands in the Marianas, many of which tend to be similar in most respects - plant life, insect life, climate.  Not all have the same species of birds.  Most importantly, not all have the brown tree snake.  The decision was made to transport birds - either wild survivors, captured and relocated, or captive-bred individuals - to snake-free islands, islands where they might have not been present originally, but where they can survive in a wild state.

At first glance, the idea seems counter-intuitive.  It was introducing an alien species (albeit, not on purpose) which led to this mess in the first place.  What if fifty years from now we're watching some Micronesian lizard species being wiped out by invading kingfishers?  No one can be positive what will happen, but the scientists involved very thoroughly took a census of each candidate island and its flora and fauna.  They came to the conclusion that it would likely work out, and decided it was worth the risk.

The partnership requires the participation of many players.  Government agencies have the authority to allow the transfers.  Local peoples have the knowledge about the landscape and the presence or absence of birds or snakes.  Zoos have the expertise for breeding the birds in captivity, or maintaining birds that are temporarily held captive as they are moved from island to island.  Together, they are accomplishing the nearly-impossible task of restoring some of these species to the Marianas, some for the first time in decades.

It's not that Guam itself is being written off as doomed - they fight to control the numbers of the tree snake continues.  Still, the sooner members of the affected species are back in the wild living under natural conditions, the brighter their future will be.

Wednesday, May 20, 2015

From the News: NMI students learn about nature's treasures

One of the major problems with invasive species, habitat loss, and other environmental problems is that it leads to a creeping norm.  Consider the Mariana Islands, where for decades the brown tree snake has reigned supreme, while many of the once plentiful endemic island birds have vanished.  To the children growing up on Guam, the brown tree snake must seem to be the native; in the wonderful event that the Guam rail and other island birds were ever successfully reintroduced, it is they who would seem the aliens.  Likewise for habitat loss - if every generation grows up with a more degraded environment than their parents knew, pretty soon the standard of what is considered a normal, pristine environment is lowered as well.

It's exciting to see that children in the Northern Marianas are being given the chance to explore and study the biodiversity that (still) surrounds them.  Only by teaching the next generation to understand and value the natural world around them can we hope to ensure that they will step up to become its next generation of protectors.

Students examine the skeleton of a whale (from Marianas Variety)

Sunday, May 17, 2015

Sporcle Quiz: Birds of Guam

This month, we met three bird species - the Guam rail, the Mariana fruit dove, and the Micronesian kingfisher - which suffered as a result of the introduction of the brown tree snake to Guam.  these three weren't the snake's only victims, however.  this month's quiz shows how the bird-life of Guam was impacted by the snake's arrival on the island.

Saturday, May 16, 2015

Species Fact Profile: Micronesian Kingfisher (Todiramphus cinnamomina)

Micronesian Kingfisher
Todiramphus cinnamomina (Swainson, 1821)

Range: Micronesia, Palau
Habitat: Forests, Woodlands, Mangrove Swamps
Diet: Insects, Lizards, Crustaceans
Social Grouping: Solitary or Paired
Lifespan: 10-12 Years, Maximum 20 (Captivity)
Reproduction: Both parents build the nest (usually in a tree cavity or termite nests), nesting season is December through July. Two eggs are incubated for 23 days. chicks are fed by both adults and fledge at 40 days.  Sexual maturity is reached at 3 years
Conservation Status: IUCN Extinct in the Wild (Guam subspecies)

  • Body length 20-24 centimeters, weigh 55-85 grams
  • Cinnamon brown plumage with a blue tail and metallic green-blue wings; males and females look alike,  except for the paler breast feathers in the female
  • The kingfisher makes its first morning call at (almost) the same time every morning, so regularly that local people used it to tell time
  • Often hunt from tree branches and other exposed perches, swooping down when they sight prey; prey is seized and then beaten against tree branches to kill it and (in vertebrate prey) break bones
  • Thee subspecies - the nominate, from Guam, is the largest; the other two are T. c. reichenbachii (from Pohnpei) and T. c. pelewensis (the smallest, from Palau).  The now-extinct Ryukyu kingfisher (known from a single specimen) may also have been a subspecies of Micronesian kingfisher.  The living subspecies are sometimes described as separate species
  • The Guam subspecies was driven to extinction in the wild following the introduction of the brown tree snake to the island; the last 29 birds in the wild were captured for captive breeding in the 1980's, and the species had vanished in the wild by 1988

Wednesday, May 13, 2015

A World of Weeds

In the first chapter of his book Sailing with Noah, Saint Louis Zoo President Jeffrey Bonner stands outside of his office, watching drama unfolding at his bird feeder.  House sparrows, starlings, and rock doves (pigeons) bickered and squabbled, with one unfortunate sparrow getting the worst end of the deal.  Bonner was mulling his options, deciding whether or not to intervene.  However, "before I could move, I had a... thought.  Not a single one of those birds were supposed to be there in the first place.  All three species - house sparrows, starlings, and pigeons - are interlopers."

If the brown tree snake's spread across the islands of the Pacific could be likened to a blitzkreig raid, then the pigeon, starling, and sparrow would be more like a march of world domination.  From their native lands they have now spread across the globe in the wake of human activity... and they haven't traveled alone.  Besides our domestic animals (many of which have gone feral in new lands), a host of other animals have followed humans across the world and established themselves around the globe.

If European birds have invaded North America, then at least the North Americans can take comfort in knowing that gray squirrels and Canada geese have invaded Europe.  Brown rats, cane toads, raccoons... these animals belong to a select group of species which I call the "wildlife weeds."

Weed wildlife, like weed plants, are tough, adaptable, and tend to be generalists.  Some are invasive to the areas where they are found now, some have been native, but have changed their behavior dramatically.  They breed readily and thrive in a variety of habitats.  Most importantly, they do not seem troubled by the presence of humans, and many have adapted to take advantage of humans as a provider of habitat and food.  As a result, they tend to out-compete more sensitive species, eventually supplanting them.

There's a beautiful creek in the park near by home, one where I go bird-watching on my days off.  Incredibly, despite its seeming perfection for waterfowl, I almost always see only two species - Canada geese and mallards.  On the rare occasions when I do see something else, the bird in question usually takes off in a panic as soon as it notices me, even if I'm far away.  Mallards and geese are comfortable around people - they don't waste energy flying away from me, and some even approach me looking for food (doubtlessly spoiled by picnickers elsewhere in the park).   For many island birds, a lack of fear of man proved disastrous to their survival.  For many weed species, lack of fear of man (or at least general indifference) is a winning strategy.

I'm afraid that we may be moving towards a world where most species are either extinct or found only in the last remnants of wild habitat away from humans.  Instead, the world will be filled with a cadre of weed species, which will be the same all over the planet.  It won't matter if you are in New York, Nairobi, or New Delhi, the animals in the park, the birds in the trees, will all be the same.

We'll have created new, blended, simplified ecosystems, far less unique and magical than the ones that used to exist.  And the world will be a much drabber, sadder place.

Tuesday, May 12, 2015

Zoo Review: Smithsonian Conservation Biology Institute

When William T. Hornaday first began to image the institution that was to become the Smithsonian National Zoological Park, he had something special in mind.  Rather than making a copy of the zoos that were cropping up across Europe, he envisioned a different kind of facility, one that would help him satisfy his ambition of saving - through captive breeding - the vanishing wildlife of North America, the American bison in particular.  Essentially, he envisioned the Smithsonian Conservation Biology Institute.

The only problem was, he was about one hundred years too early.

Founded in 1974, SCBI (formerly known as CRC - Conservation and Research Center) is tucked away in the farmlands of Front Royal, about an hour west of Washington DC.  Unlike its more famous sister institution in the nation's capital, it is closed to the public, only open during certain open houses and special events.  Prior to being owned by the Smithsonian, it was used by the US Army to supply horses and mules for military use.  Now, it is a breeding center for some of the most endangered species on earth, especially those which need some space and are too shy or delicate to breed easily in an urban zoo setting.  Among the species represented here include three species of crane (hooded, red-crowned, and white-naped), as well as brown kiwis, Mongolian wild horses, scimitar-horned oryxes, clouded leopards, and maned wolves.  Many of the black-footed ferrets being reintroduced into the wild start their lives in Front Royal.

Among the endangered species being worked with at SCBI are birds of the Mariana Islands, such as Micronesian kingfishers.  With highly endangered species, such breeding facilities - allowing multiple members of a species to be housed together, rather than a pair as is the case at many zoos - have a major advantage.  By housing lots of animals together in facilities designed specifically for breeding purposes, animals can easily be moved and re-paired until an ideal breeding arrangement is found.  For that reason, many of the nation's most genetically valuable "problem cranes" are sent to SCBI for breeding.

In 2001, Secretary of the Smithsonian Lawrence Small announced that the facility would be closed, part of his plan to refocus the Smithsonian around those features which were most profitable and attracted the most visitors - after deafening outcry, he backed away from the plan.  Still, it seems that the Smithsonian is now looking at SCBI with the philosophy of "use it or lose it", and it seems like the facility has been expanding rapidly since then (when I made my first and only visit, a new facility was under construction for breeding cheetahs).

The most impressive change, however, has probably been the new partnership with George Mason University to established a PhD program in conservation biology, where students learn the latest methods and philosophies of the field.  Such an integrated approach between zoo and field biology is essential to the future survival of many species.  It is developments like this that show that SCBI - while unsung and unrecognized by many people outside of the zoo community - is an important leader in the fight to save biodiversity.  If you get a chance to attend an open-house, do so.  You won't see a huge variety of animals, or a lot of beautiful exhibits.  You will, however, get a new insight into how some of our rarest species are being saved from extinction.

Sunday, May 10, 2015

Species Fact Profile: Mariana Fruit Dove (Ptilinopus roseicapilla)

Mariana Fruit Dove
Ptilinopus roseicapilla (Lesson, 1831)

Range: Mariana Islands (Extirpated on Guam)
Habitat: Limestone Forests, Secondary Growth
Diet: Fruits
Social Grouping: Solitary or Paired (Not Territorial)
Lifespan: 20 Years (Captivity)
Reproduction: Breed year round (peak breeding season April - August), nest on flimsy stick platforms in the forks of trees, usually lay a single egg which is incubated for 17-18 days, chick fledges at 14-18 days
Conservation Status: IUCN Endangered

  • Body length 22-24 centimeters, weight 93 grams
  • Males and females look alike - predominately green, with the top of the head is a deep, rose-red cap with a grey head, back, and breast; the stomach has a yellow patch, with additional yellow under the tail coverts; juveniles are completely green
  • Very arboreal, the doves primarily stay in the canopies of the trees, but may come to the ground to feed, including on invasive plant species
  • The species was last seen on Guam in 1985, extirpated following the introduction of the brown tree snake; it does, however, exist in the wild on other islands in the Marianas, as well as in North American zoos and aviaries
  • Official bird of the Mariana Islands