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Victoria, Canada

Whitworth D.L.,California Institute of Environmental Studies | Whitworth D.L.,Humboldt State University | Harvey A.L.,Channel Islands National Park | Carter H.R.,Carter Biological Consulting | And 5 more authors.
Marine Ornithology

The first confirmed Cassin’s Auklet Ptychoramphus aleuticus nests at Anacapa Island, California, were found on Rat Rock in May 2003, less than one year after the eradication of Black Rats Rattus rattus in November 2002. By 2012, auklet nesting had been detected in six discrete shoreline areas on the West and East Anacapa islets. We discovered a total of 42 auklet nests (i.e. sites occupied in at least one breeding season) from 2003 to 2012, including 17 confirmed nests (adults, chicks or eggs/eggshells observed) and 25 nests where breeding was inferred (fresh digging, guano streaking or strong auklet odor). Suspected breeding by auklets at Anacapa was first noted in June 1910. By the mid-20th century, rats had restricted breeding auklets to, at most, a few isolated pairs nesting on inaccessible cliffs. However, the population may have been extirpated before rat eradication, as we found no evidence of auklets nesting in any current breeding areas during surveys in 1991, 1994, 1997 and 2000. Subadult and adult auklets captured during nocturnal mist-netting at two current breeding areas in 1994 were likely offspring of isolated cliff-nesting pairs or birds from colonies on nearby islands. Once rats were removed, prospecting by subadult auklets may have facilitated initial colony growth and occupation of some previously unused breeding habitats. Continued searches and nest monitoring are needed to further document post-eradication colony growth. © 2015, Marine Ornithology. All rights reserved. Source

Sealy S.G.,University of Manitoba | Carter H.R.,Carter Biological Consulting

Two specimens of adult Crested Auklet (Aethia cristatella) have been taken at sea in the North Atlantic Ocean: (1) near Iceland in August 1912 and (2) near Nuuk (formerly Godthb), southwest Greenland between 1986 and 1972. An adult Parakeet Auklet (A. psittacula) was taken at Lake Vttern, Sweden in December 1860. These rare inter-ocean vagrants probably traveled from the Chukchi Sea east through the Canadian Arctic Archipelago to the Atlantic Ocean and may have arrived long before they were collected. Breeding distributions, limited post-breeding movements, weather patterns, timing and plumage of Atlantic and Pacific vagrants, small number of Atlantic vagrant records and the lack of inland records of these species east of Alaska in North America, support this route. Information about rare occurrences of auklets in the Atlantic Ocean enhances our knowledge of overall patterns of rare long-distance vagrancy versus more frequent vagrancy in alcids and other seabirds. Source

Sealy S.G.,University of Manitoba | Carter H.R.,Carter Biological Consulting
Canadian Field-Naturalist

From 1979 through 2009, 81 records of long-distance vagrancy in the Long-billed Murrelet (Brachyramphus perdix) in North America south of Alaska were examined to assess body condition and survival after first observation. Sixty-one records were of live birds, of which 38 (62.3%) were discovered at sea along the west coast of North America, 18 (29.5%) were encountered inland, and 5 (8.2%) were encountered along the Atlantic coast. Fifteen of the 20 individuals salvaged (19 adults, 1 juvenile) were discovered on lake shores (75.0%) and the other 5 (25.0%) on marine coasts; 85.0% were dead when initially found (15 dead, 2 shot), and 3 (15.0%) were moribund (2 died within one day, 1 later released). Of 10 sexed individuals, 5 were adult males, 4 were adult females, and 1 was a juvenile female. Eight of 10 murrelets observed foraging were diving on lakes, but 2 others surfaced with fish; two species of common freshwater fish were removed from stomachs of 2 birds shot by hunters. Most birds (72.1%, n = 61) disappeared after one observation, which suggests survival and moving on; one bird stayed at the same location for at least 25 days before disappearing. Dead or dying Long-billed Murrelets found on shorelines of fresh water may have been too emaciated to regain lost mass after arrival-they weighed less than those shot, presumably because they were not able to locate prey or too weak to capture it. Survival for weeks or longer on freshwater stopover sites better explains how Long-billed Murrelets move across North America, with some reaching the Atlantic Ocean. Long-surviving vagrants may establish a new breeding population of Long-billed Murrelet on the west coast of North America. © The Canadian Field-Naturalist. Source

Carter H.R.,Carter Biological Consulting | Ainley D.G.,983 University Avenue | Wolf S.G.,Center for Biological Diversity | Weinstein A.M.,California Audubon
Marine Ornithology

In February 2015, a special paper session about the range-wide conservation and science of the Ashy Storm-Petrel Oceanodroma homochroa (ASSP) was held at the Pacific Seabird Group annual meeting. The main goal was to share information amassed during the past 20 years on this species, which breeds almost entirely in California, United States, for formulating future research and conservation actions. One key result is the six papers on ASSP and two on Leach’s Storm-Petrels O. leucorhoa in this issue of Marine Ornithology. In this introduction, we augment contributed papers with a summary of historic and recent knowledge about the ASSP breeding range, key conservation issues and data gaps. The largest breeding concentration is at the South Farallon Islands in central California, but four other concentrations occur in southern California at the Channel Islands (Prince, Santa Barbara-Sutil, northwest Santa Cruz and northeast Santa Cruz). Over the past two centuries, many ASSP breeding colonies have been affected by introduced mammals and human-altered breeding habitats. Population decline due to heavy avian predation has been documented at the South Farallon Islands since 1972; decline due to eggshell thinning from organochlorine pollutants is suspected in the Channel Islands since the 1950s. Eradication of introduced mammals, reduction of pollution and social attraction (vocalization broadcasting and artificial nest sites) have helped to restore population size at certain colonies. © 2016, Marine Ornithology. All rights reserved. Source

McIver W.R.,U.S. Fish and Wildlife Service | McIver W.R.,Humboldt State University | Carter H.R.,Carter Biological Consulting | Carter H.R.,Humboldt State University | And 3 more authors.
Marine Ornithology

In 2008–2011, social attraction (i.e. provision of artificial nests and nocturnal vocalization broadcasting) was used to restore a small colony of Ashy Storm-Petrels Oceanodroma homochroa at Orizaba Rock off Santa Cruz Island, California, United States. This colony had declined 74.1% from 27 nests (1996) to 7 (2005), or -17.5% per year (1995–2004) using a colony size index. In contrast, a nearby reference colony, Cave of the Birds’ Eggs, increased 72.7% from 11 (1995) to 19 nests (2005) but colony size index trend (1995–2004) was non-significant. With social attraction, number of nests at Orizaba Rock almost tripled from the baseline mean of 12 (2005–2007) to 33 (2011), reflecting increases of 22.4% per year using the colony size index (2005–2011) or 26.5% per year based on colony size (2005–2011). In 2008, four eggs were laid in artificial nests; by 2011, petrels laid eggs at 11 of 30 (36.7%) artificial nests and visited nine more (30.0%). In comparison, reference colony size increased from the baseline mean of 22 nests (2005–2007) to 24 nests (2011) or 9.3% per year using the colony size index (1995–2011). Relatively high breeding success at both colonies in 2005–2011 apparently reflected reduced organochlorine pollutants, adequate prey resources, relatively low avian predation, and low or no impacts from squid-fishing lights. In 2010, Common Ravens Corvus corax discovered and dismantled 12 artificial nests; modifications were made in 2011 to prevent raven access. Social attraction resulted in restoration of the Orizaba Rock colony to its 1996 size, demonstrating the technique’s effectiveness in increasing colony size and encouraging storm-petrel use of artificial sites. © 2016, Marine Ornithology. All rights reserved. Source

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