Seabirds food odors

In addition to their role in chemical defense, DMSP-lyase products may also function as chemical cue in more complex trophic cascades. In the natural environment DMS-production is related to zooplankton herbivory [60] and can thus act as an indicator for the availability of food for planktivorous birds. Indeed, some Antarctic Procellariiform seabirds can detect DMS (22) and are highly attracted to the cue, as was shown with DMS-scented oil slicks on the ocean surface [61]. The odors released during zooplankton grazing (DMS) as well as those of zooplankton itself (e.g., trimethylamine and pyrazines) are attractive to birds [62], thus assisting vertebrate search behavior. 

Shorebirds use their sense of taste when probing sand for food. The purple sandpiper, Calidris maritima, and the knot, Calidris canutus, forage much longer in jars that contain food buried in sand, or sand with an extract of food, than in jars with plain sand (Gerritsen etal, 1983). Table 12.3 lists the responses of various seabirds to prey odors. 

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