The Black-faced Spoonbill (Platalea minor) uses habitats that are intertidal or within 2-3 km from tidal areas for feeding and loafing. Habitats used for feeding are water bodies containing fish and shrimps and a relatively wide zone of shallow water with a depth ranging between 6 and 21 cm. The bottom consisted of fine sediments with no or little vegetation or other obstructions such as stones, twigs, branches and roots of trees, wide and deep channels, or debris. They have a preference for highly turbid water, but seemed indifferent to salinity, which was varied between 0‰ and 48‰. Such sites are found on flooded intertidal mudflats, and also in tidal lagoons, brackish pools, fishponds, and gei wai (traditional ponds for shrimp farming in mangrove areas). Feeding habitats have to contain suitable food and also be relatively safe. In contrast with the requirements for their feeding habitats, the choice of loafing areas is extensive, and includes places of relative safety: undisturbed, with an open view for early discovery of predators in time and the possibility of easy escape. Shallow (<15 cm) water is necessary for bathing. They loaf in water of a depth of 0-15 cm and also on land, in trees and on human-made structures. Habitat characters, other than water, are subordinate to those of safety. The difference in requirements is evident in narrow channels between high and dense vegetation where Black-faced Spoonbills feed, but where they never loaf.

The Black-faced Spoonbill (Platalea minor) has often been considered to be a mainly nocturnal feeder. The present study shows that this species is better classified as crepuscular, being predominantly active around sunrise and sunset, but they may also feed during the day and at night. The periods of twilight and the tides interact in the timing of feeding. On average, just over 4 hours per day (17%) is spent for feeding, about 19.5 h (81%) loafing and less than a half hour (1.6%) flying.

Selected sites of Gujarat State, India, were surveyed for the flamingo count, from 11 to 26 January 2003. A total of 28,333 Greater Flamingo (Phoenicopterus ruber roseus) and 369,901 Lesser Flamingo (Phoeniconaias minor) were counted, which is the highest number recorded from India. Highest concentrations of flamingos were recorded in the Gulf of Khambhat (305,664), followed by other coastal sites of Gujarat state (50,317) and the Gulf of Kachchh (42,137). Greater Flamingos were equally distributed on Gulf of Khambhat (29%), Gulf of Kachchh (38%) and other coastal sites (32%). Lesser Flamingos were concentrated in the Gulf of Khambhat (80%). 99.6% of the Greater Flamingos were found in wetlands near the coast, with only 0.4% on inland freshwater wetlands. The Lesser Flamingos were exclusively found on the coastal wetlands. In coastal wetlands, both species showed clear habitat preference: 82% of Greater Flamingos were distributed in saltpans and 77% of Lesser Flamingos were on coastal mudflats.

Concomitant with increasing numbers of the Double-crested Cormorant (Phalacrocorax auritus), catfish producers in eastern Mississippi and western Alabama have reported damage caused by cormorant predation. VHF telemetry was used to document movements of 25 cormorants from all known night roosts in the aquaculture producing areas of eastern Mississippi and western Alabama, January-April 1998. A total of 193 day locations and 396 night roost locations of the cormorants were obtained. Each cormorant was found in the study area for 57 ± 4 (SE) days. Each cormorant averaged three night roosts (range: 1-8) and spent 20 (±2) days at each night roost site. Over 95% of cormorant day locations were within 19 km of their night roosts. Catfish pond use by cormorants varied between roost sites. Cormorants from five of eleven night roosts had ≥30% of subsequent daytime locations on catfish ponds and birds from five of the six remaining night roosts did not visit catfish ponds on the following day. Foraging distance and frequency of night roost interchange was less for birds in this study than those reported from other aquaculture regions. We suggest roost harassment efforts should be focused on specific roost sites and some roost sites should serve as unharrassed refugia from which cormorants are less likely to cause damage to aquaculture.

The breeding colony of the Double-crested Cormorant (Phalacrocorax auritus) on East Sand Island in the Columbia River estuary has grown dramatically over the last 13 years, in contrast to declines at other colonies along the coast of the Pacific Northwest. Immigration from other colonies has occurred and the East Sand Island colony is now the largest for the species on the Pacific coast of North America. Despite substantial increases in the size of the East Sand Island colony, overall numbers of the West Coast subspecies (P. a. albociliatus) appear to be slowly increasing relative to the interior population (P. a. auritus). Based on the most recent regional population data available, a conservative estimate indicates that the colony on East Sand Island represents over 30% of P. a. albociliatus breeding adults. We advocate that the subspecies P. a. albociliatus be considered a distinct population segment and managed according to overall population size and trends for this subspecies.

Great Cormorant (Phalacrocorax carbo) diet was studied during three years (2001-2003) in an area where Arctic Kelp (Laminaria hyperborea) is extensively distributed off the central Norwegian coast. A total of 608 diet samples, 378 (62.2%) chick regurgitations, 22 (3.6%) whole fish, and 208 (34.2%) pellets were collected from the colonies at regular intervals during the chick-rearing period. From these samples a total of 1,013 food items (after pairing the otoliths) were isolated, representing 18 fish species. Gadoids, mainly Cod (Gadus morhua) and Saithe (Pollachius virens) dominated the diet (75% numerically, 86% by biomass). During the first year of the study, Cod represented nearly 50% of the diet, but decreased to 13% in 2003. At the same time, the occurrence of Saithe in the diet increased from 23% to 65%. For Saithe age II-group fish dominated the diet in 2001, and I- and II- group dominated in 2002 and 2003. For Cod 0-group fish dominated the diet in 2001 and 0- and I-group fish dominated in 2002 and 2003. The decrease in Cod in the diet of the Great Cormorant most probably reflected the decrease in the Norwegian coastal Cod population, and that the increase in Saithe in the diet is related to the relative increase in the abundance of this fish prey as the abundance of Cod decreased.

Diets were examined and analyzed for 418 wintering Double-crested Cormorants (Phalacrocorax auritus) collected from January to mid-April 2001 and October to December 2001 at an oxbow lake in southeast Arkansas. The fish community was also sampled to examine prey availability. Gizzard Shad (Dorosoma cepedianum) and Yellow Bass (Morone mississippiensis) were the most important species in cormorant diet. Other, less important, cormorant prey species included Channel Catfish (Ictalurus punctatus), cyprinids (minnows), and sunfishes (Lepomis spp.). Diet varied by season and sex. Cormorants consumed higher proportions of cyprinids and Channel Catfish in the autumn than the remainder of the over-wintering period. In general, females consumed Gizzard Shad more than males, while males consumed Channel Catfish more than females. Neither genders consumed notable amounts of sport fish. Prey size did not differ between the sexes, but did vary by season. These data demonstrate the relative importance of forage and rough fish and the lesser relative importance of sport fish in the diet of cormorants over-wintering on an oxbow lake in southeast Arkansas.

Little is known about wetland selection by Lesser Scaup (Aythya affinis) during any phase of the breeding cycle, particularly in the northern boreal forest region, where most of the North American population of scaup breeds. We used survey data (1989-98) for 402 wetlands near Yellowknife, Northwest Territories, Canada to assess frequency of scaup brood occurrence. In 1999, features of 80 randomly selected wetlands (21 used and 59 not used by scaup broods) and 27 wetlands used repeatedly by brood-rearing scaup were evaluated (N = 107 total). Discriminant function analysis using all wetland measurements was used to classify scaup use of 77 randomly selected wetlands; classification criteria were subsequently used to predict brood use of the remaining 30 hold-out wetlands. This randomization procedure was repeated 100 times, producing an average classification success of 88% (95% CI = 77% to 97%). Broods occurred more often on larger, deeper wetlands with water lilies and amphipod crustaceans, the latter being an important food for adults and ducklings. Wetlands created during road construction were used less often, possibly because these tended to be smaller, shallow, less likely to have amphipods, and had a different vegetation regime than natural wetlands.

The 24-hour habitat use and home range of the Laysan Teal (Anas laysanensis), an endemic dabbling duck in Hawaii, was studied using radio telemetry during 1998-2000. Radios were retained for a mean of 40 days (0-123 d; 73 adult birds radio-tagged). Comparisons of daily habitat use were made for birds in the morning, day, evening, and night. Most birds showed strong evidence of selective habitat use. Adults preferred the terrestrial vegetation (88%), and avoided the lake and wetlands during the day. At night, 63% of the birds selected the lake and wetlands. Nocturnal habitat use differed significantly between the non-breeding and breeding seasons, while the lake and wetland habitats were used more frequently during the non-breeding season. Most individuals showed strong site fidelity during the study, but habitat selection varied between individuals. Mean home range size was 9.78 ha (SE ± 2.6) using the fixed kernel estimator (95% kernel; 15 birds, each with >25 locations). The average minimum convex polygon size was 24 ha (SE ± 5.6). The mean distance traveled between tracking locations was 178 m (SE ± 30.5), with travel distances between points ranging up to 1,649 m. Tracking duration varied from 31-121 days per bird (mean tracking duration 75 days).

The spatial distribution and use of feeding areas by Olrog’s Gull (Larus atlanticus) breeding within a 34 km² inlet at Golfo San Jorge, Argentina was investigated. Radio-transmitters were deployed on eight breeding adult birds during the late incubation period in 2001. Feeding areas were identified by means of radio-telemetry on the basis of 93 bird locations during a total of 89 foraging trips, and by direct observation of instrumented birds on 23 occasions. Both telemetry and visual data indicated that Olrog’s Gull fed almost exclusively within the inlet. In all, 85% of mapped locations (N = 93) were within 3 km of the colony, near the mouth of the inlet. The birds were consistent in the use of one particular area, and most of the tracked birds foraged mainly in one or two areas. Mean number of trips per day was 4.1 ± 0.99 (range = 1-9) and mean trip duration was 109 ± 31.2 min (range = 15-645 minutes). Both variables differed significantly among individuals. Gulls foraged at all states of the tide, although all eight individuals were more likely to forage during mid and low tides than during high tides. The small foraging range of Olrog’s Gull is defined by the spatial extension of intertidal habitats with crabs, being their main prey during the breeding season. Our results confirm the relatively high ecological specialization of Olrog’s Gulls shown in previous diet studies and their dependence on intertidal areas with grapsid crabs.

Numbers of Great Black-backed Gulls (Larus marinus) and Herring Gulls (L. argentatus) along coastal New England have changed dramatically during the last century. In recent years, Great Black-backed Gulls have displaced Herring Gulls from optimal breeding sites, thus potentially contributing to the recent decline of the Herring Gull. Although the quality of foraging habitat is also a strong determinate of reproductive success, potential for competition and interactions between these two species in natural foraging habitats have been largely ignored. In this study, the diet and prey preference of the two species were compared. In addition, the spatial and temporal patterns in foraging activities were examined and interspecific interactions in the rocky intertidal zones were also described. Diet and prey preference of the two species greatly overlapped, with both species consuming a large percentage of marine invertebrates (30-60%), especially crabs. Foraging differed, and the Great Black-backed Gull consumed more crabs from the shallow subtidal zone than the Herring Gull. In regions where numbers of gulls were relatively high, Great Black-backed Gulls initiated all aggressive interspecific interactions. In September, when some Great Black-backed Gulls had moved from breeding to overwintering grounds, 1) the size of Jonah Crab (Cancer borealis) carapaces increased in Herring Gull prey, and 2) the numbers of Herring Gulls consuming crabs increased. These findings suggest that during the breeding season, aggression by the Great Black-backed Gull, especially in areas of high numbers, may suppress the ability of the Herring Gull to forage and obtain larger crabs from the shallow subtidal zone at our study site.

Leach’s Storm Petrel (Oceanodroma leucorhoa) is a difficult species to census because the birds nest in burrows, are nocturnal, and spend most of their life at sea, only coming ashore to breed. Simply locating a suspected petrel burrow is inadequate for management and conservation purposes because it is not known if the burrow is in use. The traditional method, of “grubbing”, or reaching into suspected burrows to determine occupancy, is invasive, and of limited accuracy. Playback of specific calls during the nesting period may be used to check for burrow occupancy. I conducted a test of grubbing in comparison with vocal playbacks and use of a portable video camera to determine which methodology was most accurate, least invasive and most efficient in time and cost investment. The use of playbacks showed the most promise as a quick, low cost method for surveying these burrowing petrels. The camera method, though as thorough as the playbacks, was more expensive and time consuming, while the traditional method of grubbing proved to be highly inaccurate and invasive.

A questionnaire on ardeid nesting colony distribution and nesting numbers in Guangdong, Guangxi and Hainan, South China was sent to academics, forestry officials and nature reserve staff in 2001. A total of 44 colonies was reported, of which a third was found in Pearl River Delta, the most important ardeid nesting area in south China according to this study. Although data were missing from over half of the known colonies, 2,300 nests of seven species were reported in Guangdong. In Guangxi, there were 2,365 nests of at least seven species, but little information was available for Hainan. Field counting of nests, and strengthening the protection of colonies against egg and chick collection, are recommended.

Habitat selection by the Tundra Swan (Cygnus columbianus columbianus) was evaluated on the Colville River Delta prior to oil field development (1982-1989). Tundra Swan territories comprised a lake, used for refuge and foraging, and terrestrial habitats and ponds near the lake’s perimeter used for foraging and nesting. Tundra swan sightings from early and late summer aerial surveys were used to investigate habitat selection at the territory and within-territory scale. At the territory or lake scale, swan sightings/lake increased with lake size, and increased from discrete to tapped (i.e., connected to a river channel) to drained lakes within size categories. Overall, 49% of the variation in swan sightings/lake was explained by lake size and type, a size-x-type interaction term, and the proportion of lake perimeter comprised of Halophytic Ponds and Halophytic Wet Meadows. At the within-territory or within-lake scale, foraging swans significantly selected Halophytic Ponds, Halophytic Wet Meadows, and Fresh Ponds relative to Uplands; nesting swans significantly selected Halophytic Ponds and significantly avoided Fresh Wet Meadows relative to Uplands. Vegetation sampling indicated that sites used by Tundra Swans on river channels and tapped lakes were significantly more likely to have Sheathed Pondweed (Potamogeton vaginatus) than control sites. The three major components of Tundra Swan diet were Carex sedges, Sheathed Pondweed, and algae, together comprising 85% of identifiable plant fragments in feces.

We present the first detailed study of the diet of Glossy Ibis (Plegadis falcinellus) in Europe, from an expanding breeding colony in Doñana, southwest Spain. In 2000, fecal samples, mainly from adults, were collected from 15 nests. In 2001, 36 regurgitates were collected, mainly from large chicks. Fecal contents were dominated by aquatic beetles (Coleoptera) and dragonfly (Odonata) larvae, which were present in 100% and 93% of samples respectively. Regurgitates contained mainly aquatic beetles (41% by aggregate percent, mainly Cybister spp.), dragonfly larvae (29%, mainly Sympetrum fonscolombei, Aeshna mixta and Anax imperator), Sharp-ribbed Salamanders (Pleurodeles waltl, 12%) and Carp (Cyprinus carpio, 7%). The absence of vertebrate and other hard remains from feces was presumably due to their excretion in pellets. Thus fecal analysis is not a suitable method to investigate the food of the Glossy Ibis. The results suggest that there may be no major difference in the diet of breeding adults and their chicks, and that the recent increase in numbers of this ibis in Doñana is not explained by the abundance of introduced Red-swamp Crayfish (Procambarus clarkii) in the breeding area.

In Heidelberg, Germany, a flock of feral Swan Geese (Anser cygnoides) and Eurasian Coots (Fulica atra) feed together on a lawn during winter. It was investigated whether the presence of geese provided benefits to coots in terms of reduced vigilance and whether the association incurs costs, e.g., by reduced foraging success. Further, the hypothesis was tested whether a decrease in vigilance rate is mirrored by an increase in feeding rate. A digital video camera was used to record behavior of the same individual. Head-up movements were considered to have vigilant function when the bill was raised up from the foraging position to a position nearly parallel with the horizontal line, or when raised to a position higher than the body (“high-cost vigilance”). Coot feeding in the presence of geese showed a significantly lower scan rate. Steps per minute did not differ between the coot with and without geese, but the time taken for 30 pecks was significantly shorter in the presence of geese. There was a significant negative correlation between feeding and scan rate, suggesting that scanning decreased peck rate. Further, scan rate was inversely correlated with total flock size (number of coot and geese), suggesting that coot recognized the geese as flock mates. Coot benefited from feeding in the proximity to geese by a lower scan rate and a higher peck rate, but they did not encounter costs in terms of reduced food quality as measured by step rate.

Island-wide surveys for the endangered Mariana subspecies of the Common Moorhen (Gallinula chloropus guami) were conducted on Guam and the Commonwealth of the Northern Mariana Islands from May through September 2001. Based on these counts, the total adult moorhen population is estimated to be 287, with 154, 41, 2, and 90 adult moorhens on Saipan, Tinian, Rota, and Guam, respectively. Results suggest an overall increase in birds on Saipan and Tinian, although moorhen numbers on Guam may be declining. High counts of moorhens on Lake Hagoi, Tinian, during the wet season suggested movement from Saipan to Tinian occurs at the onset of the wet season each year. Conservation efforts need to consider Saipan and Tinian moorhens as a single demographic unit. Further, monitoring of moorhens, invasive vegetation management, and predator and ungulate control on wetlands are critical for this small population.