Monday, October 21, 2013

Farallonathon Wrap-up

Day 2 (Oct 5th) - The day after our big wave, we awoke to fairly gusty east winds. Although east winds do not typically bring large numbers of birds, they can bring interesting birds that don't normally cross large bodies of water. So we were hoping for raptors, especially for a hawk or an eagle. A big chunk of our day, though, was devoted to getting our groceries from The Rainbow, a boat in the Farallon Patrol. The Farallon Patrol consists of several skippers that volunteer their time and boats to ferry people and supplies to and from the island. In addition to bringing us food, this boat brought out a new intern, Xeronimo Castaneda, and departed with Kristie Nelson. After The Rainbow departed, Dan Maxwell and Jim Tietz took our boat over to a massive flock of seabirds feeding off the east side of the island. Here we found our one-and-only Rhinoceros Auklet amongst the thousands of Common Murres. Back on the island, we found several other arrivals, including a Rufous Hummingbird, which was our first for the fall. Normally, we see these in late August and September, but we saw very few birds during those months, so we were happy to finally see one. We also found two Brewer's Sparrows, a Grasshopper Sparrow, a late Bullock's Oriole, and our first European Starlings of the fall (a flock of 30). East winds are also great for migrant insects, and we added several such as Painted Lady, Monarch butterflies, and four species of dragonflies: Blue-eyed Darner, Green Darner, Variegated Meadowhawk, and Black Saddlebags. Our final addition was from a pair of Harbor Porpoises that strayed far away from their typical near-shore local. The 17 additional points from this day, plus one for a Willow Flycatcher positively identified from a photo taken the previous day, brought our total up to 128.






Day 3 (Oct 6th) - Our third day started out just like the day before, with strong east winds, warm temperatures, and greater than 60 miles of visibility. Although these winds did not bring us a big bird wave, a few new arrivals visited us to keep the day interesting. Surprisingly, this weather brought out four Barn Owls, which were found roosting in the three trees around our houses. Historically, Barn Owls used to be quite rare, but their numbers have increased by 310%. in the past 15 years. During this increase, we have documented numerous Cassin's Auklets and other breeding seabirds that have been killed by the Barn Owls. Other western migrants included Tree Swallow, Pacific Wren, Vesper Sparrow, and Lark Sparrow. These winds also brought us our best day of the fall for East Coast warbler diversity, with just one Western Palm Warbler, one Blackpoll Warbler, and one Black-and-white Warbler. September typically brings us the East Coast warblers, but the wind and fog must have kept them away. A second Blue-footed Booby joined the one first seen on Day 1, which added another five points for being a CBRC bird. Our first shark point of the Farallonathon happened when Cameron Rutt spotted a shark surface off of Shubrick Point. At the end of the day our total had crept up to 145.



 

Day 4 (Oct 7th) - The winds switched to northwest today, starting out light, but then strengthening. Combined with 30 miles of visibility, these conditions bring few migrant birds. Once it became obvious that there were not many arrivals, Boo Curry and Jim Tietz visited West End Island to conduct a Northern Fur Seal count at their Indian Head colony and to look for tags. Before the 1850's, the Farallones had a Fur Seal rookery of a few hundred thousand individuals. Unfortunately, once Europeans discovered this, they set about to kill as many fur seals as they could and shipped the pelts to China for profit. After several years of exploitation, any remaining fur seals abandoned their colony on the Farallones and were not seen again on the islands until the 1970's when the occasional individual would haul out to rest. In 1996, a pup was discovered at Indian Head Beach on West End Island. Following this discovery, annual ground survey visits were made to the colony to document its growth. In 2006, we noted that the colony had dramatically increased in size, and we noted that there were several fur seals with tags on their fore flippers. Since tags can provide the known age and sex of each seal as well as its origin, we increased the frequency of trips to the colony to improve our understanding of this colony's demographics. So far, we have read over 100 tags at this colony. The vast majority of the seals with tags were tagged at the San Miguel Island colony, which is in the Channel Islands off southern California. However, we also found a tag that was from the Commander Islands off northeastern Russia. On this last trip, all the tags appeared to be from San Miguel Island, except for one that may be from another location. Now that the government shutdown is over, we may get an answer. At the end of our survey, we had counted 486 individuals on land, and we estimated that there were at least 100 in the water right off the colony. The colony still has a long ways to go to reach a hundred thousand. But so long as we continue to protect their rookery from human exploitation and disturbance and their feeding grounds in the California Current from over-fishing, they should continue to rebound.

Only four points were added this day from the following sightings: a pair of Blue Whales seen far to the south from the lighthouse during a cetacean survey, one Pomarine Jaeger seen during the afternoon seawatch, and one Rock Pigeon and one Least Flycatcher seen during an area search. These four points brought our total up 149.





Day 5 (Oct 8th) - Strong northwest winds and clear skies meant that many birds departed and few arrived. Only one bird arrived that gave us a new point, an Aleutian Cackling Goose. It showed up behind our house extremely thirsty. We gave it a little water which it gratefully accepted. This was our only point for the day, so our paltry sum increased to 150.


Day 6 (Oct 9th) - Even stronger northwest winds gave most of the birds that were still on the island a nice tailwind for departure. No points were added this day, so our total remained at 150. 

Day 7 (Oct 10th) - The dawn weather appeared more promising, with light winds out of  the west, and the visibility down to just 5 miles. Sadly there were not many birds about. But then during the AM area search, Cameron spotted a Great Crested Flycatcher. Although there were 11 previous records for the island, this was the first since 1989! In addition, this species is on the CBRC review list, so it counted for five Farallonathon points! Other species this day that were new for the week were Killdeer, Parasitic Jaeger, South Polar Skua, Lapland Longspur, Wilson's Snipe, and Short-eared Owl.


In addition to birds, we found two new species of insects, a Familiar Bluet, which is a kind of migratory damselfly, and a Farallon Cricket, the only endemic species on the Farallon Islands.


Our final point was found at 9:30 on this last night of Farallonathon. The Farallon crew set out to find the only salamander on the island. Ironically, the name of this species, which occurs on an island with just 4 introduced trees, is the Arboreal Salamander. It is uncertain how this salamander got to the island, but it's possible that it came across the ocean on a log as has been documented in the San Francisco Bay (fide, Peter Pyle), or perhaps it was assisted by humans on a boat, or the species may have persisted here ever since the islands split away from the mainland millions of years ago.



With the 11 bird points (6 regular + 1 CBRC), 2 insect points, and 1 salamander point, our final total stood at 164 points. Compared to the previous 21 years of Farallonathons, this year ranked 13th. Despite our auspicious first day, poor subsequent weather and zero shark attacks meant we were doomed to have a low score. We hope you enjoyed hearing about our Farallonathon and support our cause for conservation. If so, please consider giving to the Farallon program at the following website: 


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