Saturday, September 15, 2012

Drama on the high seas

Sparkling ocean on 9 September 2012 


In the mid-late afternoon, I scanned the horizon from Bodega Head and noticed Sooty Shearwaters flying north.  Through a binocular view, on average there were ~10 shearwaters flying by per minute, sometimes as many as 30.  (The image below shows one shearwater against the sunlit waves.)


There were also small groups of terns (a little too far out to identify with certainty, but possibly Arctic Terns).  That set the stage for jaegers, so I searched closely and spotted a few jaegers, probably Parasitic Jaegers (Stercorarius parasiticus), chasing terns.  

Especially during migration and in winter, Parasitic Jaegers often practice kleptoparasitism — they harrass other birds until they drop their fish and then snatch up the food for themselves.  Although this is a distant shot, you can see the jaeger's silhouette.  The tern it's chasing is slightly below the jaeger's lower wing tip.




September is a good time of year to watch for this "drama on the high seas!"


No comments:

Post a Comment