Abstract: Understanding the behavior of birds around tall structures such as electrical-transmission lines, communication towers, and wind turbines is important in assessing the potential effects of those structures on bird populations; it is especially important for threatened or endangered species. We studied responses of the mostly crepuscular/nocturnal Hawaiian Petrel (Pterodroma sandwichensis) and the mostly nocturnal Newell's (Townsend's) Shearwater (Puffinus newelli; Aves: Procellariiformes) to coastal and near-coastal transmission lines on Kaua‘i Island, Hawai‘i, USA, in 1992–2002. Hawaiian Petrels responded to transmission lines significantly more often (19.1% of the time; N = 209) than Newell’s Shearwaters did (7.4%; N = 392), responded significantly more often with decreasing distance from a line, and responded significantly less often if a study-site was dark (i.e., unlit by ambient lights from nearby towns) than if it was light (i.e., lit by ambient lights from nearby towns), regardless of whether the sky was light (i.e., daylight or crepuscular light conditions) or dark (nocturnal light conditions). In contrast, Newell’s Shearwaters showed little variation in response rates by distance or by whether the study-site or sky was light or dark. Hawaiian Petrels mostly responded to transmission lines by changing flight velocity and flight altitude, whereas Newell’s Shearwaters mostly responded by changing flight direction and flight altitude. The higher response rates and more-buoyant flight characteristics of Hawaiian Petrels than Newell’s Shearwaters may contribute to lower rates of fatality of Hawaiian Petrels than Newell’s Shearwaters at coastal and near-coastal transmission lines on Kaua‘i.

The island of Kaua'i, Hawaii, USA, holds a large breeding populations of the endangered Hawaiian Petrel (Pterodroma sandwichensis) and a majority of the world population of the threatened Newell's Shearwater (Puffinus newelli). We evaluated island-wide population trends of both species. For Newell's Shearwaters, we considered radar counts at 13 sites between 1993 and 2013 and annual island-wide tallies of fledglings retrieved after being grounded by light attraction in 1979-2015 (Save Our Shearwaters [SOS] program). For Hawaiian Petrels, we considered radar counts alone. Radar data indicated a 78% decline overall in numbers of Hawaiian Petrels (at an average rate of similar to 6% per year) and a 94% decline overall in numbers of Newell's Shearwaters (at an average rate of similar to 13% per year) during the survey period. Most (92%) radar sites showed significant declines of Newell's Shearwaters across the entire survey period, as did 62% of sites for Hawaiian Petrels. The SOS recovery effort collected 30,522 Newell's Shearwater fledglings between 1979 and 2015. When we compared this dataset in pre- and post-Hurricane Iniki (September 1992) periods, we found a significant downward trend after Hurricane Iniki, similar to the trend seen in the radar data. The large-scale declines found in this study are not surprising, considering the significant threats facing both species on Kaua'i, which include powerline collisions, light attraction, introduced predators, and habitat modification-threats which were potentially exacerbated after Hurricane Iniki. Improved conservation initiatives and an increased understanding of the various threats facing the 2 species are key to reversing these declines.

The Marbled Murrelet Brachyramphus marmoratus is listed as Threatened under the US Endangered Species Act throughout the southern portion of its range (i.e. Washington, Oregon and California; USFWS 1992), where it flies up to ~80 km inland from nearshore waters to nest on limbs of old-growth coniferous trees (Nelson 1997, Piatt et al. 2007). Information on the seasonal activity and flight altitudes of murrelets at inland sites is lacking but important for evaluating disturbance impacts to murrelets from timber operations and other human activities and for determining collision risks associated with wind turbines, transmission lines, communication towers and other tall structures. Public agencies and developers are particularly interested in this information to assist in evaluating collision risk at land-based wind energy projects within the range of the Marbled Murrelet. Further, the information would assist the US Fish and Wildlife Service in development of protocols for studies of Marbled Murrelets at proposed wind energy projects. Studies of murrelets at inland sites have focused almost exclusively on the summer breeding period, when inland flight activity presumably is greatest (Nelson 1997). Most information on inland flight activity outside of the breeding period is based on audiovisual surveys by Naslund (1993) and O’Donnell (1993). The scope of inference for these studies is limited due to inherent biases in the detectability of murrelets at inland sites during audiovisual surveys (Jodice et al. 2001, Smith & Harke 2001, Cooper & Blaha 2002). Information on flight altitudes of murrelets traveling between the ocean and inland nest sites is similarly limited to a small number of radar-based studies (e.g. B. Cooper, unpub. data; Stumpf et al. 2011).

The Marbled Murrelet (Brachyramphus marmoratus) is a high profile, federally threatened seabird, but no reliable estimates of population trends at inland breeding areas exist for this species. We conducted land-based radar studies of Marbled Murrelets at 3-7 sites on the Olympic Peninsula, Washington, in 1996-2002 and 2004 to estimate population changes and to examine relationships between our counts and oceanographic conditions, murrelet productivity, and regional at-sea counts of murrelets. Morning radar counts of murrelets varied significantly among and within sites but did not decline from 1996-2004, suggesting that the inland breeding population of murrelets is stable in this area. A retrospective power analysis indicated that we had a 25% and 56% chance of detecting 2% and 4% annual declines, respectively. Thus, if relatively small annual declines did occur during our study period, there is a high probability that they would have gone undetected, even though they could add up to a biologically important decline over time. It is unlikely that murrelets on the Olympic Peninsula declined by >= 6% annually, however, because retrospective analyses indicated that power to detect such declines was > 88%. There was no significant relationship between radar counts and at-sea counts or productivity of murrelets in the nearby San Juan Islands during the study period. We also did not detect a relationship between radar counts and mean sea-surface temperatures or the Northern Oscillation Index, suggesting that variation in oceanographic conditions (e.g., the strong 1998 El Nino event) was not associated with variation in morning radar counts of Marbled Murrelets. A prospective power analysis indicated that small (2%-4%) annual declines could be detected with reasonably high power (>= 80%) with the current radar sampling design by extending the study to 11-15 years.

Characteristics of nocturnal bird migration are poorly understood for many regions of the United States. This information will be critical in areas where wind power projects are proposed. We used portable marine radar to conduct a nocturnal bird migration study at multiple sites along the Allegheny Front, West Virginia, on 45 nights during autumn 2003, to document migration characteristics at a proposed wind power project. Nocturnal passage rates were highly variable among nights, ranging from 8 to 852 targets/km/hour, with a seasonal mean of 241 +/- 33 targets/km/hour at the primary (central) study site and 199 targets/km/hour for the entire proposed development. Mean flight altitudes also were highly variable among nights, ranging from 214 to 769 m above ground level (agl), with a mean flight altitude of 410 +/- 2 m agl. Flight directions indicated that most migrants crossed, rather than followed, the Allegheny Front ridgeline. We believe portable marine radars, when coupled with a rigorous study design, can collect important baseline information on avian migration and address site specific questions posed at proposed developments. Concurrent collection of low-altitude migration and avian fatality data could help elucidate which metrics are most useful for predicting avian fatalities at wind power developments.

We used marine radar to study nocturnal bird migration at the Vansycle Ridge and Stateline wind-energy projects in northeastern Oregon and southeastern Washington during fall 2000, spring 2001, and fall 2001. Our study was designed to monitor waterfowl, shore-bird, and passerine movements during spring migration and passerine movements during fall migration. Flight directions (mean ± 1 angular deviation) of surveillance radar targets were in seasonally appropriate directions at Stateline and Vansycle Ridge during fall 2000 (169 ± 33°, 165 ± 39°), spring 2001 (10 ± 35°, 7 ± 32°) and fall 2001(160 ± 53°, 166 ± 53°), respectively. Passage rates (mean targets/km/h ± 1 sx̄) of targets were similar between Stateline and Van-sycle Ridge and were higher during spring 2001 (45.1 ± 6.6, 48.3 ± 6.2) than during fall 2000 (20.8 ± 2.3, 19.0 ± 2.0) and fall 2001 (21.6 ± 2.5, 26.3 ± 2.5), respectively. Flight altitudes (mean altitudes ± 1 sx̄; collected from 0 to 1500 m above ground level) were similar between Stateline and Vansycle Ridge during spring 2001 (506 ± 4.7, 579 ± 4.8) and fall 2001 (647 ± 7.0, 606 ± 7.5), respectively, but fall altitudes were significantly higher than spring altitudes at both sites. A minimum of 85% (spring 2001) to 94% (fall 2001) of targets were observed at altitudes above proposed turbine heights at both sites. Understanding the basic components of nocturnal bird migration in specific locations can help site future development projects in a manner that will help conserve nocturnal migrants.

We studied movements and distribution and abundance of endangered Hawaiian Petrels ('Ua'u [Pterodroma sandwichensis Ridgway]) and threatened Newell's Shearwaters ('A'o [Puffinus auricularis newelli Henshaw]) on the island of Hawai'i in May-June 2001 and 2002. We recorded radar targets of either species at 14 of the 18 sites but recorded no birds visually at any site. Movement rates of petrels and shearwaters were very low (0-3.2 targets per hour) over all except one of the sites (Waipi'o Valley: 25.8 targets per hour). We saw radar targets moving from shortly after sunset throughout the rest of the sampling, suggesting that both petrels and shearwaters were present. Highest movement rates occurred 1-2 hr after sunset, when primarily Newell's Shearwaters are flying. Timing of evening movements suggests that Hawaiian Petrels fly over the northern and southern parts of the island and may dominate on Mauna Loa and Mauna Kea. In contrast, timing suggests that Newell's Shearwaters fly over essentially the entire island (except in the southwestern part, where no birds appear to occur), dominate numerically in the Kohala Mountains, and occur in low numbers on Mauna Loa, in the Puna District, and on the northern slopes of Mauna Kea. Evening flight directions were predominantly inland at all sites except four. The limited radar data suggest that a substantial population change did not occur in the Puna District from 1995 to 2001-2002.

Bird migration was monitored for 4 years (1987 to 1990), at 2 central Alaska lo- cations proposed for huge Air Force radar screens. Nearly 10,000 flocks of large birds were re- corded; 30% of these flocks included swans. Approximately 7% (n = 211) of these swan flocks were composed of 2 or more species. Mixed flocks of tundra swans (Cygnus columbianus) and trumpeter swans (C. buccinator) were recorded most often (103 flocks). Swan flocks also con- tained geese (80 flocks) and ducks (16 flocks). Swans also were observed migrating with sandhill cranes (Grus canadensis, 3 flocks) and large gulls (Larus spp., 2 flocks). Mixed flocks always were flying in the long line formations typical of swans in migration and were intermixed rather than grouped. Only in the case of cranes were the swans outnumbered by other species.

A modified vehicle-mounted, X-band marine radar system was used to study the movements of marbled murrelets (Brachyramphus marmoratus) at inland and coastal sites in northern California during July. The ability of the radar to discriminate murrelets from other targets, and to estimate abundance was assessed. Murrelets were detected by radar at distances up to 1.3 km. Radar recorded the distance, ground speed, flight direction, and flight behavior (such as circling). The average ground speed of murrelets was 77 km/hr (range = 56-105 km/hr). Ground-based observers recorded an average of 67% of the murrelets within 700 m at inland sites that were recorded by radar. Using ground speed as a identification criterion, radar correctly distinguished murrelets from other bird species 87.8% of the time at coastal sites and 97.8% at inland sites. The only species contributing to identification error at inland sites was the band-tailed pigeon (Columba fasclata). Radar has advantages over round-based observers as it does not rely on murrelets to vocalize for detection and can detect murrelets over a large area, regardless of variability in light conditions, observers' auditory and visual abilities, fog, and background noise. The benefits of using radar to understand the inland flight behavior of murrelets include better interpretations of ground-based observer survey data, better estimates of the number of birds using an area, collection of data that are not biased by murrelet vocalization rates, increased understanding of landscape level flight behaviors and use of flight corridors, 24-hr sampling ability, and a more detailed analysis of seasonal and daily changes in abundance inland sites.

Declining populations of two endangered species of seabirds on Kauai, Hawaii--the Dark-Rumped Petrel and Newell`s Shearwater--have been the emphasis of a three-year research program to determine the causes of bird mortality and fallout and to recommend preventive measures. This study refined scientific understanding of the timing of bird movements, enabling future biologists to sample rates of avian traffic more efficiently and perhaps better identify the times when it would be most beneficial to reduce outdoor lighting, which has been linked to fallout. The study also identified three specific areas where collisions would be most beneficial. A sampling site was established in the highlands along a transmission line that runs from the south shore to the north shore through the interior and in proximity to several shearwater colonies. This site has provided a much clearer picture of Procellariiform behavior and collision mortality rates in the coastal areas. Volume 2 of this report describes the ecology of the Dark-Rumped Petrel and Newell`s Shearwater on the island of Kauai.