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Rice fields are important wildlife habitats; however, intensive agricultural practices have reduced the population of farmland birds. As a high-level consumer, the great egret ( Ardea alba ) serves as an indicator of the overall biodiversity of rice fields. However, little is known about the effects of farming methods on the feeding habitat selection of the great egret. Therefore, we examined the influence of eco-friendly and conventional farming methods on prey characteristics and great egret feeding behavior in rice field ecosystems. We employed focal observations and trap-based sampling to quantify prey characteristics and great egret feeding behaviors in eco-friendly and conventional rice fields. Great egrets showed more hunting attempts per minute and a higher intake rate in conventional fields, but feeding efficiency did not differ. Moreover, they consumed larger loaches in eco-friendly fields than in conventional fields. Great egrets exhibited slower feeding behaviors in eco-friendly fields due to the increased handling time of larger prey, such as loaches. Eco-friendly fields supported a higher abundance of larger-sized loaches than conventional fields, indicating their potential for supporting a higher abundance of great egrets. Our findings highlight the importance of sustainable farming practices for the conservation of the great egret.

Temporal trends (2006–2019) of metals (Cd, Co, Cs, Cu, Fe, Hg, K, Mg, Mn, Na, Rb and Zn) and nonmetals (Br, Cl and Se) were assessed in livers of great egrets ( Ardea alba ) from São Paulo Metropolitan Region, Brazil. Male and female concentrations were compared and the relation between body mass and contaminant levels was evaluated as well as the risks of contaminant levels for the birds. Large variations were observed for toxic elements (Cd and Hg) over time. Some specimens presented toxic levels of Hg, Cu, Fe and Zn. Females presented lower concentrations of Br, Co, Cs, Rb, Se and Zn, while body mass and Zn were negatively correlated.

Double-crested cormorants (Phalacrocorax auritus) and great egrets (Ardea alba) have an extensive history of human-wildlife conflict with the aquaculture industry of western Mississippi, USA, due to their depredation of cultured catfish (Ictalurus spp.). Although aquaculture is abundant, western Mississippi also contains naturally occurring water bodies that offer alternative forage opportunities to these species. How cormorants or egrets distribute themselves among these 2 foraging options is unknown, but it has been generally assumed each species uses aquaculture disproportionately more because of the high density of available prey. To test this assumption, we surveyed these species on aquaculture and naturally occurring water bodies using aerial surveys from October through April of 2015–2016, 2016–2017, and 2017–2018. We modeled the proportion of each species on aquaculture as a function of year, date, and weather-related variables using quasi-binomial generalized linear models. Egrets used aquaculture consistently more than what was proportionally available to them and use was not influenced by any of the variables we measured. Proportional use of aquaculture by cormorants was lowest during October through January but steadily increased through April, indicating a distribution shift toward aquaculture in the months immediately prior to their migration. The highest proportional use of aquaculture by cormorants occurred in 2016, a year when lethal control measures were not allowed against cormorants. Conversely, the least proportion of cormorants on aquaculture was in 2015 when cormorants could be lethally controlled under authority of an Aquaculture Depredation Order. This trend highlights the potential influence of changes in mortality risk, caused by changes in policy regarding lethal take of cormorants, on cormorant distribution between foraging options.

What draws us to the beauty of a peacock, the flight of an eagle, or the song of a nightingale? Why are birds so significant in our lives and our sense of the world? And what do our ways of thinking about and experiencing birds tell us about ourselves? Birdscapes is a unique meditation on the variety of human responses to birds, from antiquity to today, and from casual observers to the globe-trotting \"twitchers\" who sometimes risk life, limb, and marriages simply to add new species to their \"life lists.\" Drawing extensively on literature, history, philosophy, and science, Jeremy Mynott puts his own experiences as a birdwatcher in a rich cultural context. His sources range from the familiar--Thoreau, Keats, Darwin, and Audubon--to the unexpected--Benjamin Franklin, Giacomo Puccini, Oscar Wilde, and Monty Python. Just as unusual are the extensive illustrations, which explore our perceptions and representations of birds through images such as national emblems, women's hats, professional sports logos, and a Christmas biscuit tin, as well as classics of bird art. Each chapter takes up a new theme--from rarity, beauty, and sound to conservation, naming, and symbolism--and is set in a new place, as Mynott travels from his \"home patch\" in Suffolk, England, to his \"away patch\" in New York City's Central Park, as well as to Russia, Australia, and Greece. Conversational, playful, and witty, Birdscapes gently leads us to reflect on large questions about our relation to birds and the natural world. It encourages birders to see their pursuits in a broader human context--and it shows nonbirders what they may be missing.

Great Egret Ardea alba is one of few Western Palearctic species that underwent a rapid range expansion in the recent decades. Originally breeding in central and eastern Europe, the species has spread in northern (up to the Baltic coast) and western (up to the western France) directions and established viable breeding populations throughout almost entire continent. We monitored one of the first Great Egrets colonies established in Poland to infer migratory patterns and survival rates directly after range expansion. For this purpose, we collected resightings from over 200 Great Egret chicks marked between 2002–2017 in central Poland. Direction of migration was non-random, as birds moved almost exclusively into the western direction. Wintering grounds were located mainly in the western Europe (Germany to France) within 800–950 km from the breeding colony. First-year birds migrated farther than adults. We found some, although relatively weak, support for age-dependent survival of Great Egrets and under the best-fitted capture-recapture model, the estimated annual survival rate of adults was nearly twice higher than for first-year birds ( φ ad  = 0.85 ± 0.05 vs. φ fy  = 0.48 ± 0.15). Annual survival rate under the constant model (no age-related variation) was estimated at φ  = 0.81 ± 0.05. Our results suggest that Great Egrets rapidly adapted to novel ecological and environmental conditions during range expansion. We suggest that high survival rate of birds from central Poland and their western direction of migration may facilitate further colonization processes in western Europe.

Wetlands constructed or modified by humans (human-influenced wetlands [HIW]) constitute an increasing proportion of wetland habitat in the USA. It is unclear to what extent HIW (e.g., ponds, reservoirs, impoundments, aquaculture sites, and flooded agricultural fields) provide equivalent habitat for wading birds compared with the natural wetlands they are replacing or augmenting. We compared selection of HIW with natural wetlands by Great Egrets (Ardea alba) in 2 regions containing high proportions of wetlands (73% Louisiana [LA], 39% South Carolina [SC]) and similar proportions of HIW (4.3% LA, 4.5% SC). Great Egrets in LA (n = 11) and SC (n = 19) were tracked using satellite transmitters for up to 1 year to assess selection of home ranges and foraging sites. We also compared selection of flooded agricultural fields vs. natural wetlands as foraging sites from aerial surveys of untagged egrets in LA. In SC, tagged birds showed stronger selection for HIW than natural wetlands as foraging sites, driven by use of small man-made ponds (39.9% of foraging observations), but home ranges did not contain a disproportionate area of ponds. In LA, tagged birds showed no overall selection of HIW at either scale, but unmarked egrets showed strong selection for crayfish aquaculture ponds, especially during drawdown. Rice fields provided only a short window of opportunity for foraging Great Egrets and were not selected over nearby natural sites. Despite widespread availability of HIW in the southeastern USA, our results show that natural wetlands continue to provide the majority of foraging habitat for Great Egrets; however, some HIW types (aquaculture and small ponds) may be strongly selected.

Life-history theory suggests that long-lived bird species will adjust their nesting effort according to current conditions to balance the costs and benefits of current reproduction with their long-term needs for survival and future reproduction. However, responses to the same habitat conditions may differ between species, even within the same ecosystem, to produce different nesting and population patterns. We examined differences in the nesting ecology of two sympatric wading species, Great Egret (Ardea alba) and White Ibis (Eudocimus albus), between years with high (2006) and below-average (2007) prey availability in the Florida Everglades. Clutch size of White Ibises decreased by ∼19% from 2006 to 2007, whereas Great Egret clutch size remained constant. Model selection identified rain, water depth, Julian date, year, and prey biomass as parameters that most influenced daily survival rates (DSR) of White Ibis nests, whereas nest stage, region, Julian date, water depth, and the quadratic form of water recession rate most influenced Great Egret nest DSR. Daily survival for both Great Egret and Whites Ibis nests was higher in 2006 (DSR = 0.992 and 0.999, respectively) than in 2007 (DSR = 0.981 and 0.979). Our results support the hypothesis that prey availability and hydrological factors play crucial roles in regulating populations of wading birds in the Florida Everglades. Results also demonstrated that White Ibis reproduction was more sensitive to changes in hydrological conditions and prey availability than Great Egret reproduction.

The breeding season is a demanding period in an individual's annual cycle because it must balance energy gains with the competing demands of reproduction and self-maintenance and properly allocate time and energy to both. To better understand how this balance is reached, nest-attendance patterns, food-provisioning rates, and foraging patterns were studied in radio-tagged Great Egrets (Ardea alba) breeding in a mixed-species colony in Wichita, Kansas, from May–August 2010–2013. A total 900 bird-days for 16 Great Egrets (60 ± 32 days/bird) provided 777 records of feeding sites, yielding travel times, flight velocities, and flight distances. Prey-capture rates, capture efficiencies, prey sizes and aggressive interactions were recorded at rivers, ponds, and weirs. A data logger placed in the colony from 2011–2013 recorded 3,390 arrivals and departures by 14 Great Egrets, documenting nest-attendance patterns. Provisioning intervals (196 ± 18 min [SD]; Range = 30–2,044 min) differed among radio-tagged individuals and among the three years. Round-trip distances to feeding sites in 2011 (16.3 ± 17.8 km) and 2012 (16.0 ± 7.0 km) were both were longer than in 2013 (11.1 ± 3.3 km). Flight distances to feeding sites also differed among individuals and increased with breeding stage. Strike rates (strikes/min) and capture rates (prey/min) differed by year but not by microhabitat. However, capture efficiency (successful strikes/total strikes) differed among microhabitats. Fish captured at weirs averaged six times heavier than those caught at rivers or ponds, but Great Egrets also encountered rates of aggression at weirs five to 10 times higher than at the other sites. A summary of energy gains and expenditures by radio-tagged Great Egrets is described, and differences among individual birds, among years, and across microhabitats is discussed.

Group foraging is common among wading birds, and the reasons why individuals forage in groups are of theoretical and practical interest. Although aggregations of foraging wading birds usually form within patches of high-quality habitat, individual wading birds can sometimes increase success by foraging near others. We investigated the hypothesis that individuals derive a benefit from foraging in groups separate from benefits due to habitat quality. We measured the capture rates of birds foraging solitarily and in groups at foraging sites and paired unused sites and used generalized linear mixed models and information-theoretic model selection to access the evidence that individuals increase their foraging success when foraging in groups. The capture rate of Great Egrets (Ardea alba) in groups was higher, supporting the hypothesis that individuals benefit from the presence of other foragers. This rate was highest in intermediate-sized groups but tapered off in larger groups, suggesting that interference competition limits success. Tricolored Herons (Egretta tricolor) showed a similar but less statistically precise pattern. Contrary to expectation, the capture rate of Snowy Egrets (E. thula) foraging alone was higher than that of those in groups. Although fish abundance was greater at used than at unused sites, and at sites with groups than at sites with individuals, we did not detect an effect of prey density on capture rate, probably because prey density was fairly high at all sites studied. Our study adds to the evidence for a direct benefit to individuals due to the presence of other foragers in aggregations.

A method for trapping adult herons and egrets in foraging habitats is described. This method will give researchers access to adult members of Ardeidae. Over five trapping seasons, Great Egrets (Ardea alba) and Snowy Egrets (Egretta thula) (n = 78) were captured in non-tidal areas. The technique used decoys, live bait in basins and modified foot-hold traps. It is not appropriate for catching many birds at one time. The method could be modified for similarly-sized species.