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We report the development of a colony of threatened Newell's Shearwater Puffinus newelli (NESH) at Makamaka'ole, West Maui, USA, a successful first undertaking in the Hawaiian Islands. Efforts involved the construction of two predator-proof fenced areas, removal/control of predators, placement of nest boxes, and social attraction using recorded calls and decoys. Initially, one of the management areas was intended for Hawaiian Petrel Pterodroma sandwichensis (HAPE) and the other for NESH. Exclosures were completed and mammalian predators were removed in 2013, and social attraction began in 2014. Both species almost immediately began flyovers to inspect speakers and by 2015, they had landed to inspect nest sites. Cameras recorded activity at nests during which individuals showed interest and, in at least one case, competed for the same nest. The first NESH eggs were laid in 2017, by which time HAPE had lost interest. NESH numbers continued to grow, especially after more speakers were added in 2019, when at least one but as many as five NESH chicks fledged. Two main questions arose: 1) What was the source population from which NESH had come, given their near extirpation on Maui? and 2) Why did HAPE, which are abundant in East Maui and on the nearby island of Lāna'i, eventually lose interest? Better understanding the population and behavioral ecology of these species might well inform planning for similar projects elsewhere in Hawai'i. [ABSTRACT FROM AUTHOR]

A main goal of seabird colony restoration is for the colony to become self-sustaining. To do so, elevated rates must be attained in (1) reproductive success and (2) recruitment by immigrants and birds produced at the colony. Thus, an understanding of the factors affecting reproductive success and recruitment at restoration sites is vital. We examined how spatial features at the colony level affected reproductive success of Common Murres Uria aalge (hereafter, murres) over a six-year period at Devil's Slide Rock, California, a colony re-established using social attraction techniques. Clusters of sites with similar egg-laying dates, as well as high hatching and breeding success, occurred in the densest portion of the colony, which was also the last area occupied by murres at the time of extirpation and the first area to be re-colonized. Clusters of sites with low success occurred in outlying, low-density portions of the colony. Breeding success, influenced largely by high fledging success, averaged > 60% most years. Reproductive success was greatest at breeding sites with earlier egg-laying dates, those in closest proximity to the breeding sites of other murres and the Brandt's Cormorant Urile penicillatus, and those outside Brown Pelican Pelecanus occidentalis disturbance zones. Based on our findings, for future murre restoration projects in the California Current System, we suggest (1) placing social attraction equipment in the area(s) last utilized by murres prior to extirpation, (2) attempting to establish two dense breeding groups, (3) targeting sites already utilized regularly by nesting Brandt's Cormorants, and (4) avoiding sites or habitats prone to disturbance by larger and aggressive species such as Brown Pelicans, Bald Eagles Haliaeetus leucocephalus, or Common Ravens Corvus corax. [ABSTRACT FROM AUTHOR]

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% front 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. [ABSTRACT FROM AUTHOR]