Daily Account #6- Burke Museum

today we spent half of our time working in group projects, and half of our time touring bird archives in the burke museum with the collection manager of birds there, rob faucett.

he made the point that the bird collections there were just a library of data-rich bird specimens, and that his role is that of a librarian- helping people to find the right ones. often archaeologists. it's a two-dimensional record birds of the world in time and space.

there are four different kinds of ornothology- skeletal specimens, steady skins, spread wings, and tissue specimens. plummage patterns are extremely important in identifying birds. and their breast muscles have to be strong to fly- which is one way you can tell which birds were better at flying by bone structure.

the first species we learned about was the black-footed albatross. the most interesting thing we learned was that their wings have groups of feathers in different colors/patterns because they replace them at different times, as it's too costly to replace all their feathers at once. hence they've developed the most optimal molting pattern over time-- replacing every third feather to maximize flight ability.

the next species we learned about were marbled murrelets. a group of scientists decided to look at the stable isotope signature of their feathers from species over several decades, and found that these isotopes matched with different prey species, which changed drastically from 1875 to 2012. marbled murrelets went from eating anchovy to sand lance to krill-- species that are getting subsequently smaller and smaller, meaning that the murrelets had to spend more time foraging and less time protecting their young. this goes to show that the more obvious reasons for species decline might not be the only factors that explain these things, and emphasizes the importance of keeping collections such as these to be able to refer to and use data from.

we also learned about warblers: hermit warblers, townsend warblers, and hybrid warblers. the interesting story here was that the zone where hybrids are found shifts south every year because of the interactions between the hermit and townsend warblers, whereby the townsend warblers (from the northern end) are much more aggressive than the hermit warblers, and keep taking up more territory in the zones where they come into contact, pushing it further south. however, they will soon be hitting the end of the region/climate that suits hermit warblers, so only time will tell what will happen to them.

Posted on April 29, 2012 07:07 PM by akumar