There are certain places during migration winter
where you just can't believe the amount of bird activity and the diversity of species.
Places that are magnets to migratory birds. Louisiana's barrier islands are one of them.
Between Louisiana's marshes in the open,
bountiful waters in the Gulf of Mexico lies this ephemeral ribbon of
delicate sandy islands.
They provide the only sandy habitat the region
and enable great concentrations a birds to utilize the food rich waters of the
Mississippi Delta.
During migration and in winter,
birds converge there from all over the continent.
This Sanderling comes from the High Arctic.
From the Western prairies the Long-billed curlew.
Least Sandpiper breed across Canada's boreal forest.
and Western Sandpiper come from coastal Western Alaska.
As many as 30 shorebird species make use of the islands during the year
where they join the pelicans, terns, skimmers,
and other birds to reside there year-round.
At first glance the habitat appears to be rather uniform,
but the multitude of shapes, sizes, bill types, behaviors
reveals a much more complex picture.
Different species forage in favorite micro-habitats
and the use the unique tools they possess to harvest particular sizes
of prey and types of prey.
One bird that really stands out is our largest shorebird -- the Long-billed curlew.
They have this incredibly long d-curved
bill and they're able to reach things deeper in the sand than
any other species. You'll see them walking along and sometimes they'll
run forward because they've spotted a crab or something that's
darted down into its burrow and they'll take this long bill,
shove down into this whole and start feeling around with the
sensitive tip of the bill to find the prey item.
They're adapted to the reaching these burrow dwelling animals that tend to live
farther down in the sand like
certain species of crabs and shrimp and they find most of them by forging
in the higher tidal areas where the substrate is drier and firmer.
Marbled godwits are these tall graceful shorebirds. They can live to be thirty years old.
They're usually in these small flocks forging in shallow water and they're usually
following a receding tide. And what they're doing is using this
long slightly up curb bill and they're more of a tactile
forager. They put their very sensitive bill into the sand
repeatedly in areas where they have a high probability of locating the food
items that they're after which includes small by bi-vavles like clams
and types of marine worms.
The Ruddy turnstone is a really interesting bird to watch. They're very
opportunistic in the way that they feed and have a lot of foraging methods.
Their body and all of its components are really put together in a way that gives
them a lot of leverage
and strength for pushing things around, for walking, for clambering over things
on the beach...
They've got this stocky, stout little body and these short, very powerful legs
and feet. They've got a short strong bill
and they use these attributes basically to muscle things around.
They're out there flipping over shells, pulling through seaweed,
pushing with their body, and digging things up, and finding little crustaceans
and other small invertebrates to feed on.
Western sandpipers do a lot of their foraging like a lot of the other very small sandpipers--
by probing and pecking near the wet surface for a very small size class
of organisms.
It's incredible to watch them because they're foraging and you
don't really actually see them catching anything. They're repeatedly pecking or probing
or sifting through wet sand and you know they're eating things, but their speed and
reflexes are so much faster than ours that we can't even make out what their eating.
They're just on this constant fast-paced quest for food.
The Piping plovers and Semi-palmated plovers
do what is a sort of run-stop-run foraging method.
They'll run for a little while, stop, survey the area around them
spot something and then run and grab it. They're primarily forging by sight.
They have large eyes, they have great sight, and they just have this little short bill
so they're not probing deep into the substrate. They're locating things on the surface by sight
and running over and grabbing them over and over and over.
They'll also use the technique where they'll
put one foot out in front of them and sort of wiggle it on the surface
and this might disturb potential prey so the move and they can spot them better.
Reddish egrets foraging technique is spectacular to watch.
They're basically herding and flushing
schools a small fish in the shallows
and they do this by running and leaping and raising their wings.
They're basically corralling the fish and trying to corner them in the shallows
and eventually they'll chase one down and
jab down and spear this nice fish out of the water.
The abundance and diversity of birdlife
reveals the richness of the habitats found on Louisiana's barrier islands.
For many species their very existence is
inextricably tied to these habitats. These birds have evolved over millennia
in concert with these subtle features that it's hard for us to even see.