A Day Out

Please consider the photos to be copyrighted and ask permission to use them in any way. Thanks, David Clapp

The other day we headed back to a favored haunt; the Daniel Webster Wildlife Sanctuary in Marshfield, Massachusetts. This 500+ acre site is well known to local naturalists for many reasons, primarily birds; but its topography is also very interesting. This was a salt marsh area in the early 1800s and was diked off from the sea to make into a salt marsh grazing area. The enclosed marsh then “composted” down in elevation about eight feet making the whole area a polder; land below sea level. Over the next century the land freshened and became both pasture and farm land. In the 1980s it was purchased by the Massachusetts Audubon Society and began a new life as a wildlife sanctuary.

There are a couple miles of trails and a viewing platform on the only hill. The fresh water marsh is a cattail haven and the tidal waters flow again into the creeks and make for a nice variety of fresh and brackish habitats. There are two observation blinds (hides) from which a man-made pond can be observed and photography undertaken. Well, we were here because the fields had been plowed, harrowed, smoothed, and planted in grasses. Actually that work was done twice this year. The first planting died off as we had an extremely dry summer. The second planting seems to be doing well and here in mid-November it looks a bit like a turf farm or even a shaggy golf course.

The grasses have attracted sandpipers and plovers, so in addition to the usual array of birds of prey there are now Dunlin, Black-bellied Plover, and a single Hudsonian Godwit; with a scattering of Horned Larks and American Pipits.

This site is quite well known for its birds of prey. Over the years the rough grasses produced a small mammal called a Meadow Vole by the thousands and they fed an array of hawks, harriers, and falcons. Now that the rough grasses have been plowed under on about 20% of the sanctuary things might change a bit but the birds of prey are still a feature. While we were there we saw four different Red-tailed Hawks (RTHA). This Red-tail was rather blasé as he sat on a cross bar and watched us walk past.
The adult birds develop the red tail and it is an obvious characteristic. It takes about three years for the tail to change from a striped brown pattern to a nearly totally red pattern. Both of the birds shown are adults with red tails.
In addition to the Red-tails we had two Peregrine Falcons (PEFA) zipping around the fields. They were intent on catching one of the shore birds that were on the fields and this one eventually caught a Dunlin and ate it on top of one of the poles. Most of our locally nesting Peregrines do not really migrate. They may move a couple hundred miles in total but not really changing habitat and behavior. Thus when we see what appears to be a migrant falcon it is likely a bird from Canada or Greenland as these populations migrate long distances, leap-frogging over our more sedentary birds.
The sanctuary has always been too heavily vegetated for ground-feeding shorebirds to linger. But with this years plowing and planting it is attractive to many migrant shorebirds. This image shows a Black-bellied Plover (BBPL) (four actually) and a few Dunlin (DUNL) using the exposed ground to locate edible creatures. They are most likely eating beetles and caterpillars. Black-bellies are often found in and on grasslands but Dunlin, though widespread, are not as common.
As Dunlin may be a bit of a new name for some of you, here is a closer picture of one. This is from a nearby beach where they examine the wrack line and sandy edges. It is a medium sized bird with a decurved bill. As I mentioned, they are not uncommon and here in Massachusetts will often stay in large flocks right on into and through our winter. Hardy little guys for sure.
This was the rarity that drew birders. It is a godwit; the Hudsonian Godwit (HUGO). Most of the Hudsonian Godwits migrate through central USA and they are seen in small numbers along the Massachusetts coast if you can get to the remote areas they frequent. . Hudsonian Godwits belong to a group (Godwits) that are remarkable for their long distance, non-stop migrations. The eastern population of this species, the Hudsonian, usually flies from the Canadian Maritimes out over the Atlantic, and likely for 5,000 miles non-stop, well into South America. There are other godwits that undertake similar flight; such as the Bar-tailed Godwit which flies from Alaska or Kamchatka to New Zealand and Australia in 8-11-day non-stop flights. The Hudsonian Godwit has not been found staging in South America prior to its northward migration and many of the Canadian nesting sites are still unknown. Many members of this species migrate through a very narrow track in the central part of the USA’s mid-west but as you can tell there is a lot left to learn about this species.

Now that telemetry is light and dependable recorders are easily put onto birds; emitter so light and small that the birds are not hindered. One of the Bar-tailed Godwits in Alaska was outfitted with a nano tag and then followed as it flew non-stop from Alaska to New Zealand. (Take a minute to look at a map.) That is really non-stop; no food, no sleeping, no floating on the ocean . This last migration one of the birds flew about 7500 miles (12,000 kilometers). The most staggering part of this may not be the distance but that the bird flew at about 35 mph for 11 days!! Eleven days non-stop, no food, and hit the target; landing in New Zealand. The speed averages out at just under 30 mph, (11 days = 264 hours; 7500 miles divided by 264 hours equals 28.4 miles an hour) but given that the bird flew through and around storms the distance and speed are hard to figure exactly. The bottom line is that it is remarkable, nearly unbelievable, and simply fascinating. How to they steer? How do that metabolize? How much weight do they lose? How do they navigate in the day, the night, in a storm? Part of it is that most migratory birds allow unneeded organs to shrivel up and organs that they depend on to enlarge. Thus reproductive organs are essentially non-existent during the non-breeding season making the birds lighter and aiding a bit with flying. Specialized high density fats are created to power the birds. As it is they still lose about half their body weight during the flight.

The last bird is much less remarkable in many ways; it is the American Pipit (AMPI). Another tundra nester, like the Hudsonian Godwit, with a reasonable migration south each fall. They nest in the tundra to the north and on mountain tops which simulates the tundra. In the winter they migrate to the south and are found from Southern California all the way east to Florida and south through Mexico. They walk, bobbing their tails, and blend into grass land and course fields quite completely. You can be walking a field and never know they are there until they lift up and call their name in flight; “pi pit”. They are quite common in southern agricultural fields in the winter and then less easy to see as they return to their remote and high elevation breeding areas. They are a variable bird in plumage. Some American Pipits are pretty light and plain underneath and others are a dull reddish and striped — and everything in between. At 6.5″ in length they are a good bit smaller that the 10 inch American Robin. Cryptic, quiet, smallish and not easy to find; hard to believe it’s not rare.

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