how seabirds catch food | 165reflex action. Only then do the birds decide whether to swallow. Or
bring into the mind’s eye a horde of Northern Fulmars behind a North
Sea trawler gutting the catch. As the offal is flung away, so the birds can
just about submerge if the effort of submersion is needed to rescue a cod
liver. And who has not wondered how a tern copes with the flickering
reflections bouncing off a sparkling sea as it plunges into the water to
emerge from a spray of drips with a small sand eel? However, this vari-
ety of feeding techniques has been known from well before the advent
of modern technology.
Nonetheless the array of modern sensors has shed new light on some
aspects of feeding at or close to the surface. In particular, with wet/dry
sensors, sometimes accompanied by feeding sensors, it has been possible
to learn far more about when, during the 24 hours, birds are on the
water, as opposed to airborne, and potentially feeding.
Over decades several strands of evidence gave credence, if not out-
right support, to the possibility of night- time feeding. For example sea-
birds living through the long winter months around the latitude of the
Several species of tropical seabird, including Red- footed Boobies,
are able to catch flying fish in flight.