Abundance indices of Black Scoters (Melanitta nigra. americana) breeding in Alaska indicate a long-term population decline without obvious cause (s). However, few life history data are available for the species in North America. In 2001–2004, information was collected on nesting habitat and reproductive parameters (i.e. components of productivity) from a population of Black Scoters nesting on the Yukon-Kuskokwim Delta, Alaska. A total of 157 nests were found over four years. Primarily, nests were among dense vegetation in shrub edge habitat, predominantly dwarf birch (Betula glandulosa) and Alaska spiraea (Spiraea beauverdiana), an average of 58 m from water. Females initiated nests from 11 June and 17 July across years. Clutch size averaged 7.5 eggs and did not vary annually. Nest success was highly variable among years and ranged from 0.01 to 0.37. Duckling survival to 30 days old varied among years, and ranged from 0.09 – 0.35. Nest success was poor in three of four years, likely due to predation by Red Fox (Vulpes vulpes). Black Scoters appear to have low but variable productivity, consistent with life-history patterns of other sea duck species. Information gained will direct future demographic research on Black Scoters, and highlights knowledge gaps impeding management strategies needed for population recovery.

Least Bittern (Ixobrychus exilis) occupancy surveys were conducted in the Arkansas Delta, USA, during April-July 2005–2006 to determine the proportion of area occupied and relate occupancy to habitat characteristics. Previous large-scale surveys indicated few Least Bitterns were present in the Delta. During surveys at 190 sites, Least Bitterns were detected at 15 sites in 2005 and at 16 sites in 2006. Several candidate models were tested to explain occupancy based on habitat variables. Emergent vegetation cover was positively related to occupancy while the proportion of forest within 400 m of a survey site was negatively related to occupancy. The study suggests that managing the breeding habitat of Least Bitterns for emergent vegetation cover and controlling forest cover near occupied sites may contribute to this species' recovery throughout its range.

Long-billed Curlew (Numenius americanus) populations have declined during the past 150 years in part due to destruction and fragmentation of grasslands used during the breeding season. Here, multiscale habitat characteristics best predicting number of Long-billed Curlews, detected during range-wide surveys conducted throughout the United States in 2004 and 2005, were determined. Long-billed Curlews were most often observed in habitats classified primarily as grassland habitat and secondarily as shortgrass or pasture/rangeland, all with low vegetation heights (i.e. 4–15 cm). Numbers of Long-billed Curlews were positively associated with wetland habitats on a local scale and hay/pasture areas on a landscape scale, but negatively associated with shrub/scrub on local and landscape scales and evergreen forests on a landscape scale. The study confirmed the importance of grassland, cropland, pasture and wetland habitats for breeding Long-billed Curlews across its geographic range in the United States. These results reinforce the need to conserve, manage, or create contiguous tracts of grasslands containing emergent wetlands for Long-billed Curlews throughout the breeding season and their range in the United States.

In Japan, the habitat range of Long-billed Plovers (Charadrius placidus), a typical river-nesting species, has contracted by 17% over the past 20 years. In the Tama River, Kanto region, the Tama River Research Group created a gravel bar in 2001 and 2002 by removing an invasive and non-native woody plant, Black Locust (Robinia pseudoacacia), to restore the biodiversity of the river ecosystem. The study investigated the effect of the gravel bar creation on Long-billed Plovers and their nest-site preference during the breeding seasons in 2001–2004 and 2006. After gravel bar creation, the mean number (±SE) of observed Long-billed Plovers increased from 0.4 (±0.19) to 11.0 (±1.54), which indicates that artificially constructed habitats have a potential to restore populations of Long-billed Plovers. The hatching rates in the study site varied greatly (19% to 100%) from year to year, and comparison with earlier studies was difficult due to incomplete information about the breeding conditions and differences in survey methods. Nesting probability was affected negatively by gravel size and positively by distances from forest edges, even after considering spatial auto-correlation caused as a result of having continuous sampling grids.

Although egg predation from aerial predators is one of the most important threats to ground-nesting seabirds, few populations conceal their nests under vegetation. However, little is known about the relationships between nesting habitat characteristics, nest densities and egg predation. Dry Tortugas (DRTO) Sooty Terns (Onychoprion fuscata) nest on sandy substrate. However, a substantial shift in the onset of their breeding season has increased their exposure to aerial predators, which, in turn, may have triggered a change in nesting behavior. A Bayesian model was developed to determine the relationship between vegetation cover and nest numbers, and whether such a relationship has reduced the incidence of egg predation. Over eight years, data on the number of nests, incidents of egg predation and on vegetation cover were collected from 132 survey plots. A clear non-linear relationship between vegetation cover and nesting numbers was found: thresholds of 65% cover of woody vegetation, such as shrubs, and of less than 13% of forbs, were shown to maximize the number of nests, and to significantly reduce egg predation. These results have implications for nesting habitat management and demonstrate that Sooty Terns are capable of changing their breeding behavior in response to an increase in the risk of egg predation.

Body masses of over 1,500 adult and sub-adult Black-legged Kittiwakes Rissa tridactyla were measured during breeding seasons from 1954 to 1995 at colonies in NE England. There was little change between years in the mean mass of each sex, except for a 2% increase in the 1980s and a decrease of 4–7% in 1995. The relative constancy of mass, together with high breeding success throughout, suggested that periods of food shortage in the breeding season were absent throughout the study period. Breeding males averaged 394g and were about 13% heavier than females (340g). Breeding females showed a brief and temporary increase in mass prior to egg laying, and both sexes showed a small but non-significant increase in mass during incubation. There was an abrupt loss of about 6% of mass in adults of both sexes at the time the eggs hatched, and mass remained at this lower level through the nestling period. Masses of prospecting and breeding females were similar and both showed the abrupt decrease in mass in late May and in June. In contrast, prospecting males had a consistently lower mass (377g) than breeding males throughout. The pattern and timing of the loss of mass in breeding kittiwakes did not support the hypothesis that it is induced by stress arising from the need to obtain extra food for the brood, but that it can be regarded as an adaptation for more energetically efficient flight during a period when increased flying activity is needed to obtain additional food for the brood. The assumption that a higher mass in an individual is always a useful measure of quality is probably unjustified.

A review of numbers and distribution of Red Knots (Calidris canutus) on the Massachusetts coast during southward migration indicates major declines beginning in the early 1970s. Overall numbers increased during the third quarter of the 20th Century, largely at mainland versus Cape Cod locations, and then declined early in the fourth quarter at the mainland—but not the Cape Cod—locations. Evidence suggests that both the mainland and the Cape Cod areas were historically used by knots having Patagonian destinations, but that recently the Cape Cod locations have increasingly been used by knots with wintering destinations in the southeastern United States, thus balancing out the declining numbers of knots with Patagonian destinations.

Fossil evidence indicates that diverse and abundant seabird communities were once found in the main Hawaiian Islands. However, these seabird populations have severely decreased, or even disappeared, as a result of human disturbance, habitat loss and predation from introduced mammals. Today, the vast majority of Hawai'i's seabirds nest on low-lying and uninhabited atolls in the Northwestern Hawaiian islands, some of which will not be able to withstand projected sea-level rises. As a result, populations of many seabird species will be further reduced unless suitable nesting habitat in the main Hawaiian Islands can be restored against predators.

The history of seabird management in the Hawaiian Islands is examined, tracing three overlapping stages. The first emphasized exploitation, the second recognized the damage done by humans and developed methods to remove the causes. The third and current stage focuses on restoration, initially of seabirds, and most recently of ecosystems. Restoration will require a scientific approach and documentation of successes and failures, improving the chances of success for future interventions.

Flightless and post-molt survival and movements were studied during August-May, 2001–2002, 2002–2003 and 2006–2007 for 181 adult female Mallards (Anas platyrhynchos). Birds were radiotagged just before or early in their flightless period on four wetlands that differed in size on Klamath Basin (KB) National Wildlife Refuge complex. Flightless survival varied among years but was higher on two larger than two smaller wetlands; 30-day survival ranged from 11% (SE = 6.5%) on a small wetland in 2006 to 93% (SE = 6.5%) on a large wetland in 2001, and averaged 76.8% (SE = 6.1%). Most flightless mortality was from avian botulism (64%) and predation (26%). Of the 81 radiotagged Mallards that did not die in KB, 80% moved to the Central Valley of California (CVCA) before 31 January, 16% wintered in unknown areas, and 4% remained in KB through 31 January. Mallards departed KB 21 August–13 January (average: 11 Nov 2001, 25 Oct 2002, 19 Nov 2006). Post-molt survival during August–March in KB (20.7%, SE = 6.3%) was lower than in CVCA during this (62.9%, SE = 10.1%) and an earlier study. Survival in KB was consistently high only for females that molted in large permanent marshes, and although the impact of poor survival of molting females on Mallard population dynamics is unknown, KB water management plans should be developed that maintain these habitats.

Few studies have investigated the use of aquaculture-produced foods by piscivorous birds. American White Pelicans (Pelecanus erythrorhynchos) were collected from four locations (two aquaculture, one riverine and one coastal) in the southeastern United States during winter and spring 1998–1999 to assess the contribution (biomass, frequency of occurrence) of aquaculture-produced foods and their effect on body condition. Pelican diets reflected opportunistic foraging across locations. Diet near catfish ponds consisted mostly of Channel Catfish (Ictalurus punctatus). Diets along the Mississippi River had similarly high biomass of catfish, but otolith counts suggested lower use of catfish. Diets near crawfish (Procambarus spp.) ponds included shad (Dorsomis spp.), crawfish and sunfish (Lepomis spp.); whereas diets from coastal Louisiana were predominantly salt water fish. Pelican body condition, as indexed by percent omental fat, was similar between seasons but higher at catfish ponds. Foraging at crawfish ponds did not improve body condition over foraging in natural conditions. The superabundant, large and vulnerable food source (i.e. catfish in aquaculture ponds) likely resulted in reduced energy expenditures by pelicans, which would improve body condition. Higher fat reserves could facilitate spring migration and reproductive success. American White Pelican use of catfish at aquaculture facilities is predicted to continue and likely increase.

The Torrent Duck (Merganetta armata) is a little-known species that feeds on benthic invertebrates in fast-flowing mountain rivers and streams from Venezuela to Tierra del Fuego. In Argentina the species is classified as Threatened but basic studies of its resource requirements are necessary for conservation. Prey selection by adult Torrent Ducks was investigated by comparing the proportion of prey species in duck faeces with the proportion available in the benthos. Faeces and benthos were sampled seasonally over one year, from four territories in the Manso River Basin, Nahuel Huapi National Park, northwestern Argentine Patagonia. Filter feeding Simuliidae larvae (Diptera, 41–76% number of total prey) were consumed in greater proportion than their abundance. In Arroyo Blanco, an oligotrophic stream, Simuliidae were absent and the most important prey were Gripopterygidae larvae (Plecoptera, 53%) and Blephariceridae larvae (Diptera, 23%). Simuliidae may be easy prey because, like other filter feeders, they feed in exposed places. However, where these filtering species are rare or absent (as in Arroyo Blanco), ducks consume other prey. The results show that Torrent Ducks exhibit a versatile feeding behavior, indicating that the species can adjust to changes in the benthos without disappearing in a given environment.

The Eskimo Curlew (Numenius borealis), now near extinction, was intensively hunted during fall migration along the Atlantic coast from Labrador to Long Island through the late 19th century. Scores of post-1850 records from this region have been gleaned from the literature but the rate of population decline has never been assessed. George H. MacKay's shooting journal, which has been largely overlooked, includes quantitative data on curlew abundance trends from 1875 to 1897 on Nantucket Island, Massachusetts. MacKay observed 650 curlews and his party bagged 87 during 231 hunting days logged during the flight period (21 August–2 October) over 22 hunting seasons. The last major flights were observed in 1881. Although he continued to hunt enthusiastically through the early 1890s, annual totals of curlews observed by MacKay declined significantly (r_s, = 0.40, p < 0.05) from 1875 to 1897, as did annual bag totals (r_s = -0.41, p < 0.05). Annual bag totals of American Golden Plovers (Pluvialis dominica), which often associated with Eskimo Curlews, also declined precipitously during the period (r_s, = 0.51, p < 0.01). Journal entries suggest that MacKay abandoned shorebird hunting after a string of disappointing seasons in the 1890s. MacKay's journal offers a unique historical perspective on the decline of the Eskimo Curlew, a species about which little additional historical information is likely to be learned.

Long-distance breeding dispersal is infrequent among seabirds and has rarely been quantified. Six adult Roseate Terns (Sterna dougallii) that had bred at colony sites in Buzzards Bay, Massachusetts, USA from 2004–2006 switched regions and moved 200–400 km to two colony sites in Maine between 2005 and 2007. Two of the emigrants presumably had nested for at least eight years in Massachusetts before moving to Maine, demonstrating that even long-time philopatric residents of one region may switch to another region.

Bridled Terns (Sterna anaethetus) have only recently been discovered breeding in New Caledonia, the previous nearest breeding colonies being in Eastern Australia. Bridled Tern breeding biology was investigated in a single, small (c. 100 pairs) colony during the 2003 and 2004 breeding seasons. Of 93 nests monitored, 82 were under cover (70 under rock and twelve under vegetation). Nesting location did not predict hatching success. Almost half (49%) of the 37 nests monitored in 2003 were reused in 2004. Egg-laying took place between late October and mid-January; egg volumes did not vary between the two breeding seasons. Chicks reached their asymptotic weight (132 g) at 37 d, faster than chicks in Australia (40–53 d). Wing length was the most reliable predictor of chick age. An equation based on density was generated to age eggs, and graphs to age chicks. An estimated 81% of clutches produced fledglings. Predation of tern nests by Silver Gull (Larus novaehollandiae) was not observed, but Peregrine Falcons (Falco peregrinus) were observed hunting and catching adult terns.

Recent reports have suggested that hybridization occurs between Blue-footed (Sula nebouxii) and Peruvian (Sula variegata) Boobies in northern Peru, but none included morphometric or genetic analyses of apparent hybrids. Over three field seasons, morphological measurements and blood samples were taken from four apparent Peruvian x Blue-footed Booby hybrids on Lobos de Tierra Island, and one apparent hybrid on the Lobos de Afuera islands. Feather samples were collected from one representative of each parental species and one hybrid. Morphological variation of apparent male hybrids was compared to 25 male Peruvian Boobies and 140 male Blue-footed Boobies, and variation in 540 base pairs of the mitochondrial control region and 8 microsatellite loci for all hybrids was compared to 141 Peruvian Boobies and 168 Blue-footed Boobies. Molecular sexing indicated that four hybrids were male and one was female. Male hybrid boobies showed weak transgressive segregation, all hybrids possessed Peruvian Booby mitochondrial DNA and microsatellite alleles from each parental species. Hybridization between these species appears rare and restricted to the islands where both species breed, and pre and post-mating barriers appear well established.

Many animals of the Galapagos Islands are known for unusual foraging behaviors, often feeding in a way not typical for the taxon in question. In 2003, an adult Lava Heron (Butoiides striata sundevalli) was observed feeding on an adult Small Ground Finch (Geospiza fuliginosa). The endemic Lava Heron had not been previously observed feeding on these finches that are common throughout the islands. The behavior could represent a valuable feeding strategy for herons in a situation where aquatic food resources are temporally unpredictable, as well as an additional mortality risk for Galapagos Finches.

Knock-down tags are often used to monitor population and nest attendance patterns of burrow-nesting seabirds. However, the accuracy of the knock-down method has not been considered in detail. Here, measurements of nest attendance patterns for Ancient Murrelets (Synthliboramphus antiquus) obtained by the knock-down and the radio telemetry methods were compared on a colony at Reef Island, Haida Gwaii, Canada. Radio transmitters and knock-down tags both indicated activity 79% of the time (range: 61–96%, N = 307), and the correlation between the two methods was significant. Hence, knock-down tags provide information that, although coarse, can provide an adequate indication of reproductive behavior in Ancient Murrelets without disturbance to the bird.

To test the effectiveness of patagial marking with cattle ear-tags for Australian White Ibis (Threskiornis molucca), 105 adults and 58 nestlings were fitted with tags on each wing. Resighting frequency of adults, survival of nestlings, breeding behavior and foraging movements were monitored. The resighting frequency of wing-tagged adults was compared with resightings of 160 adults marked with colored leg-bands. Survival rates of wing-tagged nestlings were compared with an equal sample of 58 nestlings fitted with colored leg-bands. Over six months, 96% of tagged adults were resighted and there was no indication of impaired flight, with foraging movements ranging up to 30 km. Wing-tagged adults were more likely (40%) than color-banded adults (28%) to be detected in a one-off survey three months after marking and 65% of tagged birds were observed nesting. Higher mortality was observed among smaller nestlings (<1100 g) compared with larger nestlings marked with wing tags, but not among those marked with leg bands. Inspection of the wings of two adult and two juvenile birds recaptured 6–8 months after marking indicated only minor feather abrasion, although further study is needed to assess long-term impacts. Because patagially-fitted cattle ear-tags are more visible than colored leg bands, can be fitted quickly with minimal trauma, and seem to have few adverse effects, they appear to be an effective technique for individually marking large adult birds.