Fall 2010 Class #4 Notes: Finishing Shorebird ID, More on Molt

Class #4 10-26-2010 

Review of Molt Strategies- Finish shorebirds.

Knowing what plumage a bird is in is a key in shorebird ID.  Know how to differentiate juvenile, formative, basic and alternate plumages.  To be an advanced shorebirder you need to know when the molts into these plumages happen for the various species.

White-rumped Sandpiper:  rare here, larger than Westerns, black legs, shorter bill than western, white eye stripe, long and attenuated, look for long primary projection.

Baird’s Sandpiper:  uncommon in fall, rare in spring.  Montaine migrant.  Up to 6000 feet.  Small flocks, thin black pointed bills.  Attenuated, above black centered feathers fringed with gray and wings so long they can be crossed, S. Hemisphere strategy, very long distance migrants.  i.e. don’t molt wing feathers in the US.  Complete formative molt.  Best to see in August to first week of Sept, look in salicornia, upper beaches, roost on upper beaches. Almost all juveniles.  Slightly larger than westerns.

Pectoral Sandpiper:  Also mostly seen in the fall, some adults in July to early August, but mostly juveniles in August thru Sept, a few in Oct.  Long greenish yellow legs.  Medium length two-toned bill, pale at the base, noticeable supercillium,  Split supercillium, fairly attenuated, slightly smaller than a dowicher, larger than a dunlin.  Look for collar, very defined, clear border. .White belly.  Salicornia, brackish or fresh water ponds.  Tend to be mid continental migrant.  There is a white mantle line.  Variable reddish on scapulars, coverts.  Some can have a reddish cap.

Sharp-tailed sandpiper:  about the size of a Pectoral.  Greenish yellow legs, similar bill.  Juvenile has very buffy breast, lacks streaks on central part, bleeds into the belly area.  Bright red cap.  Regular in the fall in small but variable numbers.   Have a white eye ring.  Eye stripe flares behind the eye.  As with other juveniles, later in the fall, they can be worn, and the white feather edges can be quite worn.  STSP has a white mantle line.  S. American strategy.  Eccentric wing molt in the formative plumage.  So don’t molt primaries in the US in fall migration.

Upland Sandpiper:  very rare in W WA in migration.  Long neck Yellowish legs, long legs.  Long tail, short wings.  Small head and small bill.  Unusual appearance.

Buff-breasted Sandpiper:  irregular in the fall.  Sewer ponds, golf courses.  Attenuated, long primaries. S Am strategy.  Bright yellow legs. Complete preformative molt.  Short pointed bill.  Beedy eye with pale head and pale eye ring.  Fringed back feathers make it a scalloped appearance.  White underwing.

Ruff:  fall migrant, mostly juveniles  Rare in spring.  Ruff is male, Reeve is female.  Ruff size of greater yellowlegs, reeve the size of lesser yellowlegs.  Three types of males.   See birding article in Birding.  Red, White and males that look like females.  Lek birds. Juvenile washed with buff on upper breast, little streaking.  (YL has streaking on breast) Brightly patterned above. Legs greenish yellow, no bright yellow.  Short thick based bill.  Long attenuated face, looks pulled forward face into the bill.  N.Hemisphere strategy eccentric molt.

Short-billed Dowichers:  Look on surfbird site for peep identification.  Best way to ID is by voice.  Fast mellow tew-tew-tew  Long billed is a sharp peek.  Early fall migrants, adults can be in TX by the end of July.  Female bills longer.  So female short-billed approach male long-billed.  Toughest plumage is worn breeding and winter plumage.  Adults first, large flocks, along the coast.  Mostly salt water.  Large flocks of hundreds to thousands of birds should be mostly or all SBs.   Short billed spotted breasts.  Slightly longer primary projection, up to 2 feathers.  (LB have none) In every plumage SB is brighter than LB.  This is due to the feathers on the back and coverts have white or rufous edges all the way up the feathers.  Note in the LB it is just the end of these feathers with rufous edging.  Two toned bill. Paler at the base. Kink in the lower bill tends to be at one place. More blunt tipped.

Long-billed Dowichers:  usually small to medium sized groups, favor fresh water ponds, bill longer, more evenly curved, more pointed.  In adult plumage stripes on flanks tend to wear off more so SB in worn plumage more spotted on flanks.  Eye placement is lower on LB, higher on SB.  Less steep forehead than SB.  Flatter posterior back in SB, more indented in the LB.   Central vein of the feathers of the covert and scapulars tend to be darker.   The black of the tail feathers is wider than the white, opposite in SB.  Helpful on some birds.

Two rules of primary molt: SB molt at coastal sites, mostly from N CA south.  LB can molt on breeding grounds and in early migration.

1.  If you see a dowicher in basic plumage away from the coast it is LB.

2.  If you see a dowicher in wing molt in the interior it is a LB, SB molts only at coastal sites, usually south of WA.

Dennis Paulson article on sandpipers in American Birds, about 2005  Flocking behavior.  Two main purposes.  One is social.  A species has similar flight patterns that aid in this.  A species of an off species falls out quickly because they fly slightly differently.  Second purpose is to avoid predators.

Sentinels see the predator first, Plovers, tringines, phalaropes, upland sandpipers and curlews.

Birds that flock together:

(Surfbirds, turnstones, rock sp)

(dunlin & sanderlings)

(Red knots and BBPL)

(Curlew and Godwits)

Sentinel species tend to space in feeding habitat, have loud calls.  Tend to have loose smaller flocks.

Probers are more at risk, have heads down more.  Dunlin, Stilt, dowichers, snipe, godwits, peeps are examples of probers.  Tend to have heads down, call less, form large flocks.  Probers tend to feed with sentinel species, when alone should need to spend more time watching out, have higher predation rates.


Stilt Sandpiper:  most juveniles.  Most in August and Sept.  August best,  E and W WA.  Mostly fresh water or sometimes brackish ponds.  Long billed, slightly larger than a dunlin, bright longish legs, blunt droopy bill, Juvenile buffy on the breast.  Somewhat attenuated, fairly long primary projection.  Fringed white back feathers.  Tend to be pickers, pick like a yellowlegs, will submerge their whole head, hold their bill down when walking feeding.

Wilson’s snipe:  cryptic coloration, both streaks and bars.

Wilson’s phalaropes:  rare migrant in W WA, breed E WA.  Poith wing. Plain wing and white tail.  Molt migrants. Gather in large groups in migration and molt in these sites.  Largest.

Red-necked phalaropes:  Much smaller than Wilson’s.    Smallest phalarope. Medium pointed bill.  Striped tail.  Striped back.  Aug – Oct.  After Oct 15th these are rare in WA.

Red Phalarope:  Plain backed.  Blunter bill. Striped tail.  Two tone shorter blunter bill.  Lighter cap and whitish forehead.   Slightly smaller than the Wilsons, much larger than the Red.