students have been studying the western gull population at Año Nuevo
Island. By attaching small GPS loggers to them, he can track their
movements during foraging trips. His preliminary results show that
some gulls forage at sea, but many simply head down to the Santa Cruz
Resource Recovery Facility (i.e. the dump).
It reminds me of some radio tracking work done at Oxford in the 1970's, herring gulls also used the dump as well as freshly plowed fields and the inter-tidal zone, only at low tide. These birds knew what day of the week Sunday was, and never went there on Sunday, for it was closed, but they couldn't remember the Queen's birthday, when it was also closed. Gulls at our dump get confused twice each year, when they arrive an hour after the dump has opened on a Monday morning in the Spring and then arrive an hour too early on another Monday in the Fall.
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