These impressions of low shorebird numbers from different spots along Long
Island are interesting and thank you all for sharing. Data collecting tools
like eBird are well suited to quantifying these impressions if they hold
up, and this is one reason why observers should make the effect to
carefully enter counts or best estimates with their checklists and to
correctly record their effort time so that meaningful comparisons can be
made. Just imagine if we had lots of eBird data over the past 100-200
years, I think the extent of the changes in bird populations at individual
sites would be staggering (and sobering).

Just to add to the previous good suggestions, the observed paucity of
shorebirds could simply be due to weather patterns. In past summers we've
seen shorebirds, especially adult shorebirds, come through the coastal
areas in obvious waves and often departing synchronously as well. So it
could be that a succession of weather systems over the past few days and
weeks have conspired in such a way that fewer shorebirds have reached Long
Island than typical. Alternatively the weather could have made it easier
for birds to push right through without pause. This is probably less likely
because its more likely that the marshes and shallow bays being surveyed
are intentional stopover points. One way to address this might be ask if
observers in other parts of eastern North America (central NY, Cape Cod,
Delaware Bay, Bay of Fundy etc) or even northeastern South America are
seeing higher or lower numbers than they expect for the date. A delayed
arctic summer might be reflected in low numbers across a wide arc of
migration stopover points.

If something has happened to the adults then we are in real trouble. This
could happen if they arrived on their breeding grounds before the snow and
ice has cleared sufficiently for them to feed. I've not heard that this was
a wide scale issue this year but I don't follow these things closely. Wide
fluctuations in the numbers of juvenile shorebirds from year to year is
well documented and broadly linked to several causative factors, most
notably the ups and downs of lemming populations. There shouldn't be too
many juveniles coming through now but they will be here fairly soon.

Cheers, Angus Wilson
New York City

--

NYSbirds-L List Info:
http://www.NortheastBirding.com/NYSbirdsWELCOME
http://www.NortheastBirding.com/NYSbirdsRULES
http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm

ARCHIVES:
1) http://www.mail-archive.com/[email protected]/maillist.html
2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L
3) http://birdingonthe.net/mailinglists/NYSB.html

Please submit your observations to eBird:
http://ebird.org/content/ebird/

--

Reply via email to