Frozen in Time

Tuesday morning started off rather overcast, but great things lay ahead, for the Tuesday Morning Group was headed to Ann Arbor to visit the University of Michigan’s Museum of Zoology, specifically to take in the bird collection.

I was early on my way to meet my carpool, so I detoured out to the fields where the snowy owls have been seen.  I did see two large white birds fly into the treeline here, but if they were snowies remains unknown.  They could’ve also been hawks…or a hawk pushing a snowy.  One of these days I will have my binocs and camera with me when I see something and will be able to make a more positive ID!

DSC_0382Soon, however, the caravan was headed up Route 94 on the way to the museum.  This natural history museum is a wonderful place that everyone should visit.  To begin with, it has some beautiful architecture – check out the ceiling in the lobby!

DSC_0386Our destination was the third floor, where Janet Hinshaw is the manager of the Bird Collection.  Ah…there’s nothing like an “old school” critter collection.  You can just feel the years of research in the place.

DSC_0389DSC_0392But not everything is old.  In fact, all the specimen cabinets are new, state-of-the-art cases, which are hermetically sealed against humidity, bugs, and people!

DSC_0396Our group was eager to start looking at birds!

DSC_0390 Janet had placed some trays of warblers, a selection of falcons, and a variety of thrushes out on the tables for us to view as she did an introduction to the collection.

DSC_0402I was drawn to the big fella in the back corner, though.  This is an ostrich skeleton.  Impressive.

DSC_0399In a case up on top of shelves, was a skeleton of a Great Auk, a bird I know from stories and history – now extinct.  It was much smaller than I expected.  Sadly, it’s height above the floor, my less-than-statuesque height, and the reflecting lights on the display case’s glass resulted in poor photos:

DSC_0406 DSC_0407 Great AukThis was the first of the extinct birds we were to see this morning.  Janet took us down an aisle of cabinets, unlocked one, and inside were the birds that we now only know from books, some rare films, or study skins like these.

First up, the Carolina Parakeet.

DSC_0413 Carolina ParakeetCan you imagine, truly, trees full of flocks of these spectacularly colored birds?  Once their flocks spread across the United States, from the east coast to the midwest, where they fed on a variety of fruits and seeds.  When settlers moved out west, and started to convert forests and the plains to agricultural lands, the birds lost habitat and food sources.  As a result, they started to feed on the commercial crop, with the predictable outcome:  slaughter by irate farmers.  By 1860 the Carolina Parakeet was rare;  it was extinct by 1920.

DSC_0414Probably the most famous extinct bird, besides the dodo, is the Passenger Pigeon.  Like the Carolina Parakeet, the Passenger Pigeon existed in large flocks.  In fact, the flocks were enormous!  They could be miles long!  But when settlers came to this continent, they saw these large flocks as a source of food.  It was the beginning of the end.

The demise of the Passenger Pigeon has been called “the most spectacular example of avian exploitation in human history” – rivaled only by the collapse of many of our ocean fisheries.    Entire railroad lines were built specifically to take advantage of the massive flocks of Passenger Pigeons in the midwest.  Market hunters would take the trains out to where the birds were roosting and feeding, and as the birds settled in the hundreds and thousands on the ground, they’d fire huge nets over the flocks and catch them.  Hundreds of tons of these pigeons would be loaded on the trains and shipped to market.

As the population declined, it plummeted.  Some suspect that the birds needed to have such huge flocks in order to locate the massive amounts of food they needed to survive.  It is also known that the birds stopped breeding – not necessarily because they couldn’t find mates, but again because their numbers were so low.  And, the hunting pressure exceeded the replacement rate.

What a shame.  And what a beautiful bird (it was).  Love the iridescence on the neck.

DSC_0419 Passenger PigeonNext Janet pulled out the woodpeckers.  As you’d probably expect, this one is the Ivory-billed Woodpecker – male and female.

DSC_0422 Ivory-billed Woodpecker (5)The Ivory-billed had two subspecies:  the North American subspecies, which was endemic to the lowland forests of the southeast, and the Cuban subspecies, found, as you would expect, in Cuba.

The primary cause of loss for these birds was hunting, although habitat loss was right up there.  In fact, it is believed that there is no longer the right kind of forest to support these birds any more.  Ivory-bills hit the news in 2004/2005 when reports came out of Arkansas about a sighting.  Teams of birders and ornithologists hit the flooded forests in search of these birds, but no conclusive evidence was found.  Might they still be there?  It’s possible, but the probability is low.  There has been no conclusive evidence since 1940.

DSC_0429 female ivory-billedThe largest woodpecker in the world was the Imperial Woodpecker, and Janet showed us a male and female of this bird, too.

DSC_0433 Imperial WoodpeckerAlso known as the Mexican Woodpecker, it was found in the forests of Mexico.  The last confirmed sighting was of a female in 1956.  I read about what happened to these birds and it just about made my blood boil.

These birds were targeted by logging outfits in the forests where they lived.  They told the locals that these birds were destroying the valuable timber that was to be logged, so in order to help the logging industry, the logging people gave poison to the locals to smear on trees where the woodpeckers were known to be searching for food.  When this happened, the population plummeted, as you can imagine.  What makes this so infuriating is that woodpeckers do not feed on live, healthy trees; and loggers do not harvest diseased, dead trees.  Was there really a conflict?  NO!  Arrrghh!

What stands out as really cool about this bird is the flipped up “do” on the female.

DSC_0440Here’s a peek inside the drawer of extinct exotic birds.  I believe the reddish ones are a honey creeper from Hawaii.

DSC_0447This fella is the Dusky Seaside Sparrow, listed as extinct in 1990.  I remember hearing about this bird when I was in college – just prior to its listing.

These sparrows were officially declared a subspecies in 1973, although they had been described as such about 100 years before.  They are (were) closely related to the Scott’s Seaside Sparrow, and depending on whether one was a lumper or splitter, the Dusky was the same (or not).  DNA testing was not held as 100 % reliable, but eventually it was determined that these two birds split ways between 250,000 and 500,000 years ago.

Duskies lived in a very small habitat area, so they were subject to the perils of “island” effects, where it doesn’t take much to wipe out a species.  In the 1940s, DDT (sprayed for mosquito control) took a huge toll:  breeding pairs dropped from about 2000 to 600.  Then the area was flooded, again in an attempt to control mosquitoes.  This resulted in the loss of nesting habitat – the population dropped again.  Next, the land was drained to enable the construction of a highway, resulting in further habitat loss.  What did in the Dusky Seaside Sparrow?  A combination of pesticides and pollution are commonly cited as the cause.

DSC_0443 dusky seaside sparrowThis pretty little bird is the Bachman’s Warbler.  Very little was ever learned about its behavior.  It was a southeastern bird, last seen in Florida in 1977.  The last confirmed US sighting was in 1988.   These little birds overwintered in Cuba, and the hurricane that struck there in 1933 devastated the population.  It is believed they became so rare that they were unable to find mates and breed.  Poof.

DSC_0451Bachman's warblerThe Labrador Duck is another species that went extinct before we knew much about it.  It is believed that the population was never large to begin with.  “They” believe that the duck’s bill indicates that is sifted through silt and shallow water for shellfish and crustaceans; this highly specialized diet/niche may have also contributed to the bird’s decline and eventual extinction, as did its lack of fear of people.  The last confirmed sighting was 1878 in Elmira, NY.

DSC_0463The Eskimo Curlew – in the 1870s huge flocks of this bird were seen all along its range, especially when it came in to forage on blueberries and other heath fruits.  When Passenger Pigeons became harder and harder to find, the market hunters turned their attention to the Eskimo Curlews.  By the late 1800s their population was in critical decline, a condition that was compounded by excessive hunting and loss of spring food sources (especially the Rocky Mountain Grasshopper) due to conversion of land to agriculture.  In less than 20 years, Eskimo Curlews were also extinct.

 

DSC_0475 Eskimo CurlewThe chicken-like bird below is a Heath Hen.  It’s a subspecies of the Greater Prairie Chicken, which can still be found.  The Heath Hen was once fairly common along the eastern US, and some believe that it was these birds that graced the first Thanksgiving table, not turkeys.  Regardless, they were extremely common during Colonial times.  By the late 18th century, these birds were so common, and so commonly eaten, that they eventually became known as the poor man’s meat – cheap and plentiful.  I’ve even read that some employment contracts that included meals dictated that the employee would not be served passenger pigeons for more than three meals a week because they would get sick of it.

As you might guess, over-hunting was the primary cause of the bird’s decline.  Soon the only population that remained was on Martha’s Vineyard, where, for the first time, laws were put in place to protect them.  For a while it looked like the protections would work, for the population rebounded and did fairly well, but then the island effect took hold again, and between disease and weather, the population suffered irreparable losses and it became extinct in 1932.

 

DSC_0476Now we branch into some of the interesting extinct birds from outside the US.  This is a pair of Huias, a bird that was found in New Zealand.  The female is the one with the really curved bill, while the male has the shorter, stouter bill.  He would whack away at wood to excavate it for insects, while she could reach further into the wood to extract a meal.  This particular example of sexual dimorphism is unusual – mostly with birds what you see is a difference in coloration or size between the sexes, if there is any difference at all.  Over-hunting for skins to mount in museums and for tail feathers to use on hats, and habitat loss (deforestation) led to the extinction of this bird.  It lived in ancient forests – complex ecosystems, that once logged, could no longer support this bird.  The last Huias were seen in the 1960s.

DSC_0468 This little fellow is the Laysan Rail.  We were all surprised to see a rail that was so small!  It was a flightless bird from the northwester Hawaiian island of the same name.  It was noted for its speed as it ran across the ground, using its wings to maintain its balance.  You can see footage of this bird here.  It’s loss was primarily due to the introduction of rabbits to the island.  The Laysan Rail ate a varied diet of invertebrates, leaves, seeds, eggs and seabird carcasses, but when the rabbits arrived, these voracious herbivores stripped the island bare of vegetation, leaving a virtual dust bowl in their wake.  The loss of plants was devastating to the birds, and not just the rail – two other species also went extinct.  In 1910 the island was at K, which is the carrying capacity of a habitat; for the rails that meant there were about 2000 breeding pairs.  By 1923, there only two left on the island.  The last Laysan Rails were seen in 1944 on the island of Midway.

DSC_0448 L aysan Rail It really is so very sad to see these losses.  And to know that they are just the tip of the iceberg.   These were just a handful of specimens from one cabinet in one collection.

The tragedy of these losses should be a lesson to everyone.  And yet, extinctions continue, often in the name of “progress.”

From this one cabinet, we moved on to other birds, ones that still exist, like the Cassowary:

DSC_0485 Cassowary (3)Tune in tomorrow to learn more about this bird (it was from P.T. Barnum’s circus) and the rest of the birds we saw this day.

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About Dahlem Center

The Dahlem Center is a non-profit nature center/environmental education center located on almost 300 acres just south of the city of Jackson, Michigan. The Center is one arm of the Dahlem Conservancy, which includes land conservancy and stewardship in its mission.
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