Hi Tweeters,


The latest issue, Vol. 4 No. 3, of Birders Journal (where *do* they put the
apostrophe?) has a fascinating article titled, Extralimital Occurrence of
Rufous-necked Stint _Calidris ruficollis_ in North America, by Christopher
J. Escott. It has many interesting things in it, one of the being a table of
West Coast, Interior N. Amer., and East Coast sightings.

I have taken the liberty of re-arranging the dates of West Coast first
sightings of Rufous-necked Stints (RNST) in calendar sequence.

MAY
May 05/69 Eureka HUM CA (northound)

JUNE
June 18/74 Crescent City DN CA
June 20/82 Tillamook Bay OR
June 24/78 Iona Is. BC
June 25/84 Bandon OR
June 26/88 Iona Is. BC
June 29/94 Santa Clara R. Est. CA


JULY
July 03/82 Tillamook Bay OR
July 03/86 Iona Is. BC
July 04/87 Santa Clara R. Est. CA
July 11/82 Santa Clara R. Est. CA
July 11/94 Santa Maria R. mouth CA
July 12/81 Santa Clara R. Est. CA
July 13/92 (1) Boundary Bay BC
July 13/92 (2) Boundary Bay BC
July 15/90 Santa Maria R., mouth BC
July 18/93 Whidbey Is. WA
July 20/84 Eureka HUM CA
July 23/83 nr. Lancaster LA CA

AUG
Aug 17/74 Salton Sea IMP CA
Aug 19/82 Tillamook Bay OR
Aug 25/78 Iona Is. BC


VCR BC sightings run:

June 24 Iona Is.
June 26 Iona Is.
July 03 Iona Is.
July 13 Boundary Bay
July 13 Boundary Bay

For an average Vancouver BC arrival of July 08
(I didn't include an Aug. 25 record, as the article shows a question mark
under the 'Plumage' heading, indicating no data)

On July 04, Al Jaramillo said:

> In my mind, this Rufous-necked Stint arrival bit is a really good
>question. What I would like to know is if the pattern of late June/early
>July arrival is real or an artifact?

It's real; although the migration period is spread all over hell's half
acre, but if you average all this stuff out, you get a *general*
arrival/peak of July 13. I'm sure my crude calculations can be refined
*much* more; i.e., average arrivals for each location on the Coast.

>Why are there so few (or none?) from
>early August, before the juvenile migration of peeps?

Good question. I suspect the answer is connected to geographical location(s)
of the non breeding/failed breeding/breeding female/breeding male/juvenile
migratory sequences of the Western Sandpipers (WESA) with which the RNST's
associate. My guess is that, given enough years, enough banding captures,
and enough attention to sexing *as well as* aging and indentification, RNST
will show a similar sequence; maybe that will help clarify the spread-out
date distribution of this species in the southbound migration.

> so the
>Rufous-necked Stint that got here definitely arrived before the main
>movement of Westerns... However, I don't think that the
>reason is that these birds happen to catch a good wind to ride

Like Jack, I disagree. It happened that at the time of the first arrivals of
WESA, there was a large high pressure dome dominating Cascadian weather for
the entire week to ten days that included the before, during, and after
period of WESA arrival. It is anecdotal wisdom here in Vancouver BC that
long distance migrant birds overfly in good weather (high pressure), and
that it takes bad weather (low pressure), with its rain and opposing winds
to stop them and force them down to where we can look 'em over for RNST's.
When the summertime Semi-Permanent Pacific High is off the BC-Washington
coast, southbound birds from the south coast of Alaska *could* fly out into
the Northern Pacific in a south*westerly* direction, pick up favorable
tailwinds on the western side of the High and make landfall anywhere from
southern Washington to southern California, arriving more-or-less as
simultaneously if not before birds doing a more painstaking stop-by-stop
down the coast. This would be the West Coast analog to southbound migrants
leaving SE from Newfoundland, picking up the Bermuda High in similar
fashion, and making landfall in the Caribbean Islands to South America. I'm
speculating they do the same thing on this coast.

>So why do Rufous-necked Stints migrate through early? I have two guesses:
>1) They are most obvious early in the season. In June and July Rufous-necked
>Stints should show a good amount of red on the plumage which makes them more
>obvious. Later on they will be more faded and duller and perhaps will have
>started moult.

Hey, we shorebird hotshots in Vancouver BC have yet to see a wussy
Definitive Alternate male (Prater et al., says females paler) RNST anyway!
They've all been in Alt 1 or pre-basic molt, probably the former. We *like*
hard ID's! The table from Escott's article shows RNST's not all that early,
but similar to WESA and Semipalmated Sandpiper.

>Related to this may be that once the Western Sandpipers
>really get going, you have very little chance to detect a stint because
>their proportion decreases relative to the Westerns.

Another factor is that 10 or 15 yrs ago you could see between 5 to 15
shorebird junkies at Iona Is. or Boundary Bay on *any* given summer evening
between late June and late August. And we were quite willing and even happy
to troll through tens of thousands of WESA nightly to find a stint. Believe
me, we didn't miss much. Now you're lucky to see one or two birders, and I
can say from firsthand knowledge that the pattern of *reporting* is far,
*far* less reliable than in the good old days. Don't get me started.

> As well, juveniles should be going through as well,

They were, but sightings rejected by a local rarities committee don't find
their way into any database of juvenile migration chronology. This points
out the fact that the local picture of stint migrational chronology is only
as good as the skills of that local committee.

Michael Price
Vancouver BC Canada
michael_price at mindlink.bc.ca

PS: Al J asked:
>Michael, I'm curious but how were you identifying the First Alternate
>(young) from the Definitive Alternate (adult) birds?

Al, I was following Peter Grant in 'Identification of stints and peeps' in
British Birds, Vol. 77, no. 7, p. 295:

"...At least a substantial proportion of first-summer individuals of some
species (Semipalmated Sandpiper, Western Sandpiper _C. mauri_, and
Red-necked Stint _C. rufficollis) apparently remain on or near their
southern wintering areas throughout their first summer and do not return
north to the breeding areas with the adults: the first-summer plumage of
these individuals is often little--if at all-- different from winter plumage."

By late June--mid July, any WESA is going to be showing as much alternate
plumage as it's gonna be showing all year, pre-Alternate molt (including
"fresh" Alternate) being pretty much over by then, I think, so if it's not
showing a fairly complete version of Definitive Alternate by then, it's
*probably* an Alternate 1 bird. And being at the N end of WESA wintering
range, I'd guess that many first-return birds don't have far to come back.

On the other hand, if it turns out that proper aging of these birds can be
done in-hand only, then I suggest dropping all age qualifiers, and simply
refer to them as 'Basic' or 'Alternate'.