Gulls in a northern elephant seal rookery (2 Viewers)

[pbgrebe]

Gulls are amazing opportunists and are great at finding ways to take advantage in various settings and circumstances (and oftentimes in some surprising ways). I saw a good example of this during the times that I observed the annual, large, seasonal northern elephant seal birth/breeding rookery located at Point Piedras Blancas along the central California coast (I attached a portrait of a mother and her ridiculously plump pup). Gulls (mainly western gulls—adults and immatures) are regularly and constantly seen throughout the rookery, walking among and flying over the elephant seals as they patrol the rookery for possible feeding opportunities. The various feeding opportunities that I saw them exploit are as follows. The most obvious of these relates to the fact that, at such a large rookery, some pup mortality can be expected. The gulls apparently are well aware of this reality and they readily scavenged the bodies of dead pups (this includes instances in which they simultaneously did so with turkey vultures). A less obvious opportunity they seized upon occurred in the aftermath of a birth. Shortly after giving birth the mother would expel the afterbirth. It was clear that the gulls knew this pattern—after a birth, gulls would gather around the mother in obvious anticipation of her expelling the afterbirth. When she expelled it, a mob of gulls would immediately descend upon the afterbirth and in a loud, frantic, ultra-competitive moment of chaos, they quickly devoured it (as an example of the intense competition among the gulls, I once observed a simultaneous tug of war between three gulls who were fiercely grappling over a membranous piece of afterbirth). I even had several observations of a gull nibbling at the remnant fragment of umbilical that was still attached to the belly of a recently born pup. The most surprising feeding opportunity seized upon by the gulls had to do with a food item that one wouldn’t expect to be on the menu of gulls. The pups could be rather messy when nursing and it was common to see milk dripping down from the teat along the mother's belly while a pup nursed. On a number of occasions I observed instances in which a gull attended a nursing pup and snuck in and plucked drops of milk from the stream that was dripping down along the mother’s belly. I also observed instances of gulls picking a drop of milk straight off the lip of a pup that had just finished nursing! Yes, gulls truly are amazing opportunists!

 

[Farnboro John]

You've mentioned gulls and TVs: a few years ago an adult Pomarine Skua paused its migration at the Donna Nook seal rookery in Lincolnshire for some days to feed on afterbirths. The views of this usually brief seawatch bird were brilliant.

John