by Robin Woods

White-Chinned Petrel (Illustration by Franklin Coombs, From "Guide to Birds of the Falkland Islands" by Robin W Woods)

Robin Woods reports that during a week long stay on Kidney Island during October 2000 he found many corpses of birds along the shore. Some were partly hidden in rolls of washed up giant kelp. All had been torn apart by scavengers and many had one or both legs missing. Many looked quite recently dead, though some have obviously been dead for a few days.

During the week a total of 176 dead birds were found. These included 13 King Shags, 40 Sooty Shearwaters and a surprising total of 123 White-chinned Petrels. These totals are probably minimal. Two of the White-chinned Petrels had metal leg bands of the type used by Shane Wolsey in the late 1980s on Kidney Island. We can therefore be fairly confident that the birds that died were from the population breeding on this Island.

Two important questions are: how did they die and where? I believe that the population of Sooty Shearwaters may be 20,000 pairs or even more and that it outnumbers the population of White-chinned Petrels on Kidney Island at least 10:1, and maybe even 20:1, yet I found three times as many corpses of White-chinned Petrels as of Sooty Shearwaters. Whatever caused this mortality, it was clearly an unusual event. Since 1995 I have camped on Kidney Island for several days each year in October and November. I previously stayed there many times in spring, summer and autumn between 1958 and 1963 and have never before seen such evidence of White-chinned Petrel mortality.

All the birds appeared to have died at sea because they came ashore waterlogged. All appeared to have fully feathered wings and I had no evidence of Sea Lions or gulls catching them by their burrows or on the beach. White-Chinned Petrels have been the victims of thoughtless longline fishing methods in the southern oceans, but it seems very unlkely that birds removed from hooks well out to sea would come ashore in the Landing Bay of Kidney Island, within a stretch of water only 300m wide between East Falkland and the island. Further, none of the beaks that were visible showed any signs of having been tom from a large fish-hook. An explanation is not obvious, but it would be good to know why these birds died in case it is possible to prevent such high mortality occurring again.