[CINC] Condor Express Birds 5-17

[Bernardo Alps]

Hi all.

This is a somewhat belated report of the May 17, 2012 Condor Express trip.

It was pretty rough in the south channel; 30 kt winds and 8 - 10 foot swells. We headed west along the coast and turned south just past Coal Oil Point. The krill was about four miles north of Carrington Point on Santa Rosa Island and from there we headed back home.

The wintering birds are pretty much all gone and the spring migration has slowed to a trickle. 

Almost all gulls have departed for their respective breeding grounds. The individuals left are immature or unhealthy birds that will not breed this year. In the harbor, I saw some 60 Western gulls and about 100 throughout the trip. There was also a first year glaucus-winged gull, five first year ring-billed gulls and a first year California gull in the harbor and about ten more California gulls in the channel. Western gulls are the only gull species that nest locally and closer to the islands the birds we see are foraging breeders. There was one Western grebe in the harbor and 11 more in the kelp just outside the harbor. Cormorant numbers were also way down with about 40 double-crested cormorants in the harbor and about 15 Brandt's cormorants along the coast.

As for migrating shorebirds, four long-billed curlews were resting on the sand spit at the harbor entrance and a flock of about 100 whimbrels flew by overhead. Red-necked phalaropes were seen in groups ranging from two to 100, but interestingly they were mainly  in the northern part of the channel; there were hardly any feeding on the krill. The only other migrants were two Pacific loons out by the krill patch.

The conditions were not favorable to spotting alcids, but I recorded two common murres and about 15 rhinoceros auklets. Both species nest on Prince Island off San Miguel and our trips take us into their foraging range.

We only saw one pink-footed shearwater but several thousand sooty shearwaters. The sooties were sitting in large rafts on the krill patches.  The tubenoses were rounded out by a single black storm petrel about mid-channel.

We didn't get close enough to the islands to see pigeon guillemonts or nesting cormorants.

While I have your attention, I would like to weigh in briefly on two subject discussed on this list recently. In her review of Wild Blue, Valerie uses a sentence that has a connotation that I imagine is a little different from what she intended. She states that Dan Bortolotti is " is one of those authors that picks a subject, does some research and then writes a book." I know Dan and I have read Wild Blue twice. He does more than "some" research; I don't think that anyone could have researched the subject more thoroughly and his grasp of the blue whale is truly amazing. I cannot recommend this book highly enough.

Then there is the topic of gray whales feeding on migration. We have had to reevaluate almost everything we thought we knew about the gray whale in recent years and new and revolutionary data continues to come in on a daily basis. We can follow some of these discoveries on an almost real time basis. Varvara's tag miraculously continues to transmit, http://mmi.oregonstate.edu/Sakhalin2011.  Then there are the 19 grays tagged in Laguna San Ignacio this year, http://swfsc.noaa.gov/PRD-GrayWhale-tracking/. 

We always thought that gray whales navigate by using acoustic cues (listening to waves breaking on shore) or by following visual cues in shallow water. Now Flex and Varavara have shown us that they can not only navigate over long stretches of open water, but they follow a perfect circle. Wow!

We used to think that gray whales fed only in the Arctic and only on the bottom but it is now accepted that they are generalist feeders that probably use a wider variety of feeding mechanisms and food sources than any other cetacean and that they can feed at any point of their migration, at least opportunistically. We know that many individuals don't go all the way to the Bering, Chukchi and Beaufort Seas and spend their summers in places like the Farallon Islands, Oregon and Vancouver Island.

Mary Lou Jones and Steven L. Swartz write in the Encyclopedia of Marine Mammals, 2nd Ed., http://books.google.com/books?id=2rkHQpToi9sC&pg=PA511&lpg=PA511&dq=encyclopedia+of+marine+mammals+gray+whale&source=bl&ots=hDhBMw66uz&sig=S79ufi-ID_PR_aGG-AX8Ch2Ixbc&hl=en&sa=X&ei=NlW5T_60KuSqiQKxwMTpBg&ved=0CF8Q6AEwAQ#v=onepage&q=encyclopedia%20of%20marine%20mammals%20gray%20whale&f=false :

"The feeding ecology of gray whales is unique and complex. The diet consists of a wide variety of benthic organisms (infaunal, epibenthic, and hyperbenthic) but also includes planktonic and nektonic organisms (midwater and sea surface) and perhaps some plants. Gray whales use three foraging methods, they typically rely on intermittent suction as their primary mode but also opportunistically employ gulping and skimming to capture midwater and sea surface species. They are able to switch techniques to exploit the most optimum prey species, or assemblages of species in any one location within their summer-fall feeding range and anywhere else in the migratory and wintering areas."  

On a personal note, I have seen gray whales feed in Laguna San Ignacio. Calves often bring mouthfuls of sediment to the surface in what appears to be practicing for feeding, but there is an area in the southeastern lagoon where whales congregate at certain times and engage in what is obviously feeding. 

Take care,

Bernardo