Hi John, Based upon input from several people (in particular, Stuart Krasnof) over the years, the key food resource used by neotropical migrants at the Hawthorn Orchard (during normal years) are the larvae of the Tortricidae moth family, collectively known as leaf-rollers. This has been a cold year and those larvae that I have analyze appeared to be significantly underdeveloped for the time of spring.
There’s a great book on Tortricidae moths in New York. I’ll try to dig up the title and authors. It was put out by Cornell University Cooperative Extension several decades ago. One other general thought about how the birds know when there’s good food supplies at the Hawthorn Orchard (and when there isn’t) has been a frequent topic of conversation I’ve had many times with Meena Haribal. Recent studies have shown that birds have very finely tuned olfactory receptors (despite earlier thoughts that birds, in general, have a poor sense of smell). If I recall correctly, when plants are under attack by insects, or are being damaged, they can release distress chemicals. It is hypothesized that when plants are under attack like this, these released distress chemicals may be detected in the air by migrating insectivorous birds, which then may descend upon an affected plant (or entire region of affected plants (i.e., cuckoos descending upon forests under attack by gypsy moths or tent caterpillars) to eat the insects, thus being beneficial to the plant and for the foraging birds. I would appreciate any more insight others may have on this topic. Hope this limited understanding helps, John! Sincerely, Chris T-H Sent from my iPhone On May 25, 2020, at 16:10, "k...@empireaccess.net<mailto:k...@empireaccess.net>" <k...@empireaccess.net<mailto:k...@empireaccess.net>> wrote: With all the neat birds reported annually from Hawthorne Orchard I wondered if anyone has studied the diet that attracts them or observed and followed up on the food they were getting? We know from the books that several species of moths are associated with Hawthorne and not sure what other caterpillars insects or other food sources there are drawing the birds. Anyone? John -- John and Sue Gregoire 5373 Fitzgerald Rd Burdett, NY 14818-9626 "Conserve and Create Habitat" N 42.44307 W 76.75784 -- Cayugabirds-L List Info: Welcome and Basics<http://www.northeastbirding.com/CayugabirdsWELCOME> Rules and Information<http://www.northeastbirding.com/CayugabirdsRULES> Subscribe, Configuration and Leave<http://www.northeastbirding.com/CayugabirdsSubscribeConfigurationLeave.htm> Archives: The Mail Archive<http://email@example.com/maillist.html> Surfbirds<http://www.surfbirds.com/birdingmail/Group/Cayugabirds> BirdingOnThe.Net<http://birdingonthe.net/mailinglists/CAYU.html> Please submit your observations to eBird<http://ebird.org/content/ebird/>! -- -- Cayugabirds-L List Info: http://www.NortheastBirding.com/CayugabirdsWELCOME http://www.NortheastBirding.com/CayugabirdsRULES http://www.NortheastBirding.com/CayugabirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://firstname.lastname@example.org/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/Cayugabirds 3) http://birdingonthe.net/mailinglists/CAYU.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --