Nycticorax Nycticorax Research Articles

Phylogenetic position of Diplostomum spp. from New World herons based on complete mitogenomes, rDNA operons, and DNA barcodes, including a new species with partially elucidated life cycle.

Diplostomum ardeae Dubois, 1969 has seldom been reported since its description from the great blue heron (Ardea herodias L., 1758) in the USA. Sequences obtained in this study from the barcode region of cytochrome c oxidase 1 (CO1) in diplostomids from black-crowned night heron (Nycticorax nycticorax (L., 1758)) in Puerto Rico matched data from D. ardeae from A. herodias in the type region. We also obtained DNA barcodes from morphologically similar diplostomids from a rufescent tiger heron (Tigrisoma lineatum (Boddaert, 1783)) and from metacercariae from eye lenses of Trachelyopterus galeatus (Linnaeus, 1766) from the Paraná River basin in Argentina and Brazil, respectively. Barcodes matched (97-100% identity) in these South American adult and larval specimens as well as in recently published sequences from metacercariae from 11 other siluriform fishes from the same region. Barcodes from the South American species, which we describe as Diplostomum lunaschiae n. sp., differed from those of D. ardeae by 7.2-9.8%, and the new species differs from D. ardeae in its size, pharynx:oral sucker length ratio, egg:body length ratio, and distribution of vitellaria. As in prior phylogenetic analysis of CO1 sequences, both D. ardeae and D. lunaschiae n. sp. were not associated with Diplostomum. In more character-rich analyses of nuclear rDNA and of mitochondrial genomes, D. ardeae was an early divergent member of clades of species of Diplostomum. Consequently, we continue to consider D. ardeae and D. lunaschiae n. sp. members of Diplostomum, in contrast to recent suggestions that these species may belong to a different genus.

Breeding Phenology and Reproductive Success of Little Blue Herons (Egretta caerulea) in an Urban Mixed-Species Colony

As human populations continue to expand into suburban and rural areas, conflicts with wildlife are likely to increase. Many populations of long-legged wading birds (Family Ardeidae) face the challenge of human disturbance both at feeding sites and breeding colonies. Little Blue Herons (Egretta caerulea) are medium-sized wading birds that often join egrets and other herons in mixed-species breeding colonies. In June and July 2018, a random sample of Little Blue Heron nests located in an urban colony were monitored from incubation to fledging. The goals of this study were to (1) characterize adult nest-activity patterns over the course of the breeding cycle, and (2) document Little Blue Heron reproductive success in an urban colony and identify sources of human disturbance. Instantaneous samples with 5-min intervals were used to record adult activity during 50 h of observation at 24 nests. An additional 77 h of continuous observation at two different nests documented fine-scale activities and changes in nesting status. Observations made at random times during morning, midday, and evening periods yielded 636 nest-hours across all breeding stages. During incubation, attending parents mostly sat (63 %) or stood (23 %) in or near their nests, spent less time in nest maintenance (5 %) and self-maintenance (scratching, preening; 5 %), and seldom (< 1 %) left the nest unprotected. By the end of the breeding cycle, nests were unattended 69 % of the time. The 26 monitored nests fledged a total 39 chicks (1.4 ± 0.3 chicks/nest attempt). The 16 successful nests (61 % of all nests) fledged 2.4 ± 0.2 chicks. Known causes of nest failure included destruction or usurpation by Cattle Egrets (Bubulbus ibis) and predation by Black-crowned Night-herons (Nycticorax nycticorax). Sources of disturbance included dogs allowed in the colony, intentional loud noises, and human presence. We compare reproductive success at this urban colony to that in less disturbed colonies reported in the literature.

Synurbic avian species in Greater Jakarta Area, Indonesia

The objective of this study is to reveal birds found in Greater Jakarta Area, and categorize the bird based on the probability of encounter, namely urban exploiters, adapters, and avoiders. Bird list of 36 sites in Greater Jakarta Area collected by other workers in the last seven years were used as the basis of determination. Percentiles were used as cut off points for each category. Of the 243 bird species found the study area, there were 8 species categorized as urban exploiters and the 3 highest ranks were the Sooty-headed Bulbul, Cave Swiftlets and Eurasian Tree Sparrow. Forty-nine bird species were categorized as urban adapters. The rest of species, which constitute a big portion of the species spotted in the Greater Jakarta (186 species, 76.5%) were categorized into urban avoiders. The nocturnal species was represented only by Black-crowned Night-heron. The presence of species exploiters and adapters showed that (a) Greater Jakarta Area still have sufficient green open spaces, including significant numbers of mature and decayed trees; (b) there were still good quality of small rivers, creeks, and swampy area; (c) small mammals were sufficient to support small raptors, and (d) bird community was quite rich to perform brood parasitism habit.

Purple Knot

Purple Knot Daniel Hornsby (bio) My mother’s birdwatching mania began with my fourteenth birthday, when she gave me a pair of exorbitantly priced binoculars she’d bought from an enthusiast in Lexington, Kentucky. They weighed as much as a Bible and hurt my neck Click for larger view View full resolution Photo by akashunnikrishnan [End Page 77] if I wore them for more than fifteen minutes. Almost immediately she reclaimed them and bought me a cheaper (and lighter) pair, and under the Kentuckian’s continued long-distance influence, we staked out eastern butterbills, Mexican snake-eaters, and greater pillowlarks in our old Subaru station wagon. One weekend she rented a cabin in Michigan so we could glimpse a rainbow mooncock (we didn’t see it, but we did spot a beautiful black-crowned night heron). Our avian résumé grew quickly, as did the Kentuckian’s influence and my number of unexcused absences from school, until at last we lugged our binoculars (we owned several pair now) down to Catspaw, Florida, to join our guru and his apostles in an attempt to glimpse one of the most elusive creatures yet: Drimble’s purple knot. The drive south was one long quiz of Latin names, migrations, and wingspans. I have no real intelligence, but I do have a knack for memorizing useless information of this sort, which is the only way I survived this particular migration and the strange days to come. I can still list an unreasonable number of finches. It was a tender age. I was, at the time, a rather chubby boy, and I wore my hair down to my shoulders. Kids at my school uniformly referred to me as “Roseanne,” from the sitcom, and a few could, by squishing their cheeks around their mouths, impersonate me with such accuracy that it would have impressed me if it hadn’t made me cry. My mom, to her credit, never shamed me for my homeliness and liked to braid and comb my hair, which she occasionally bragged about to strangers. In those years, my only prayer was a morbid one: that I would die long before her so I wouldn’t ever have to feel the pain of her loss. Her prebird period had been hard on her. While she made a good effort to appear happy for me, once every couple weeks she confined herself to her bed for a day or two, and I’d peek into her room to find her lying on top of her sheets, studying the stucco stalactites on the ceiling or staring blankly at informercials proclaiming the miraculous stain-removing properties of oxygen. But the bird-watching had changed something. I could commit a few bird-filled branches of the Tree of Life to memory if it made her happy. The Kentuckian had given us an address near Venice, Florida, and after two days of driving and pointing out Cooper’s hawks, we arrived at a locked gate and entered the passcode he’d sent on the keypad. “He doesn’t strike me as the gated-community type,” my mom said. Her intuition was not entirely wrong here. [End Page 78] The Kentuckian met us at the door. His name was Stilt Sandpiper, after the bird. A name I of course knew already but have so far neglected to say because it was so embarrassing. The name made sense, though. The man in front of me looked like a squash on stilts, the stilts being two long, calfless legs tanned the color of peanut butter. “Dorothy! Finally! You look sensational.” He gave my mom an awkward hug and squeezed my hand way too hard, as if he needed to demonstrate his superior strength to the fourteen- year-old boy before him. His fingers left long white marks on my fat hands, like the ghosts of bratwursts. Stilt helped us with our bags and told us to make ourselves at home. “Welcome to the Nest,” he pronounced (I could hear the capitalization). The walls were covered in 3D letters spelling words like beach and ocean. On an end table sat a single shell glued to a blank canvas. Stilt commanded me...

Coastal Marsh Bird Habitat Selection and Responses to Hurricane Sandy

Wetlands provide numerous ecosystem functions such as water purification, nutrient cycling, and wildlife habitat. Avian populations are indicators of wetland health, and understanding their responses to extreme events can aid in targeting restoration efforts following disturbance. Here, we assessed the habitat selection of six coastal wetland bird species (American Bittern, Black-crowned Night Heron, Great Egret, Glossy Ibis, Snowy Egret, Yellow-crowned Night Heron) related to an extreme weather event, Hurricane Sandy. We used Discrete Choice Resource Selection Functions to estimate habitat selection. Results showed species probability of use increased with lower elevation and slope, and closer proximity to marsh, salt marsh, Phragmites, and protected areas. Estimates of marsh dieback from Hurricane Sandy occurred disproportionately in areas with higher probability of species use. Species were observed farther from the coast and at higher elevations in the four breeding seasons after (2013–2016) compared to before (2000–2012) Hurricane Sandy. Our results indicate that although high suitability areas were affected by the storm, these six wetland bird species may have responded by moving inland and to higher elevation. Understanding how coastal wetland birds respond to storm events is important for conservation planning, particularly as storm frequency is projected to increase in the future.

Distribution and abundance of marsh-nesting colonial waterbirds in Prairie Canada

Waterbird species face numerous threats and many are declining globally, but knowledge of distribution, abundance, and trend remains poor for many species. Five species of marsh-nesting colonial waterbirds are poorly monitored in Canada, and especially so in the core of their range in the Canadian Prairie Provinces (Alberta, Saskatchewan, and Manitoba). We summarized published and unpublished data on abundance and distribution of breeding colonies of Western Grebe (Aechmophorus occidentalis), Franklin's Gull (Leucophaeus pipixcan), Black Tern (Chlidonias niger), Forster's Tern (Sterna forsteri), and Black-crowned Night-Heron (Nycticorax nycticorax) in Alberta, Saskatchewan, and Manitoba. We also examined the degree of overlap in nesting phenology (egg dates) and summarized survey methods that have been used to monitor the species during the breeding season—information that may be useful for the development of a multispecies monitoring program. For all species, the largest number of records of breeding colonies occurred in Alberta, with records declining eastward through Saskatchewan and Manitoba. We identified a number of breeding colonies occurring outside of currently defined species ranges, especially for the poorly studied Forster's Tern. Of 137 waterbodies hosting a colony of at least one species over the past 10 yr, 57 (41.6%) hosted colonies of at least 2 species, and 3 (2.2%) hosted colonies of all 5 species. Species tended to be reasonably synchronous in their breeding phenology, but Franklin's Gulls and Black-crowned Night-Herons tended to initiate nesting slightly earlier than the other species. We conclude that a multispecies survey timed in late May or early June to count nests and/or incubating adults, using either ground-based or aerial surveys, would likely be the most appropriate for monitoring all species jointly in the Prairie Provinces. The approach we take to compiling data from multiple sources on species occurrence and breeding phenology may be applicable to others wishing to examine the feasibility of a multispecies monitoring plan.

Comparative Analysis of Intestine Microbiota of Four Wild Waterbird Species.

Waterbirds are ubiquitous and globally distributed. Yet, studies on wild waterbirds’ gut microbiota are still rare. Our aim was to explore and compare the gut microbial community composition of wild waterbird species. Four wild waterbird species that are either wintering or all-year residents in Israel were studied: great cormorants, little egrets, black-crowned night herons and black-headed gulls. For each bird, three intestinal sections were sampled; anterior, middle and posterior. No significant differences were found among the microbiota compositions in the three intestine sections of each individual bird. Each waterbird species had a unique microbial composition. The gut microbiota of the black-headed gulls’ fundamentally deviated from that of the other bird species, probably due to a very high abundance (58.8%) of the genus Catellicoccus (Firmicutes). Our results suggest a correlation between the waterbird species’ phylogeny and their intestine microbial community hierarchical tree, which evinced phylosymbiosis. This recent coinage stands for eco-evolutionary patterns between the host phylogeny and its microbiota composition. We conclude that eco-evolutionary processes termed phylosymbiosis may occur between wild waterbird species and their gut microbial community composition.

Organophosphate flame retardants in heron eggs from upper Yangtze River basin, southwest China

The egg samples of four heron species, including black-crowned night heron (Nycticorax nycticorax), little egret (Egretta garzetta), Chinese pond heron (Ardeola bacchus) and cattle egret (Bubulcus ibis), were collected from the upper Yangtze River (Changjiang) Basin, Southwest China in early summer of 2017. Nine out of ten target organophosphate flame retardants (PFRs) were detected in these heron egg samples. The sum of concentrations of the PFRs quantified (∑PFRs) ranged from 63 to 590 pmol g−1 ww (18–185 ng g−1 ww) with a median value of 139 pmol g−1 ww (48 ng g−1 ww) among all samples. The median ∑PFRs in eggs of night herons (160 pmol g−1 ww) was higher than Chinese pond herons (median 121 pmol g−1 ww) and little egrets (median 109 pmol g−1 ww). In heron eggs, ∑PFRs were mainly contributed by tri-n-butyl phosphate (TNBP), tris (isobutyl) phosphate (TIBP), tris (1-chloro-2-propyl) phosphate (TCIPP) and tri-2-methylphenyl phosphate (TMPP). Alkyl-PFRs accounted for approximately 28%–85% (median 57%) of the nine PFRs quantified while the rest is contributed by aryl-PFRs and chlorinated PFRs. Lower levels of PFRs in little egret eggs were found upstream than downstream of the Yangtze. In addition, the daily intakes of PFRs through ingestion of heron eggs were estimated at lower levels.

Effect of piscivorous and omnivorous colonial birds’ activity on structure, abundance and diversity of soil free-living nematodes. Preliminary results from a study of the impact of avifauna on soil biota in Israel’s Mediterranean Coastal Plain

Abstract The soil biota, including soil microorganisms and free-living nematodes, was investigated in the nesting and roosting habitats of the following piscivorous and omnivorous colonial birds: black kite (Milvus migrans), great cormorant (Phalacrocorax carbo), black-crowned night heron (Nycticorax nycticorax) and little egret (Egretta garzetta), in Israel’s Mediterranean region. Abiotic variables, abundance, trophic structure, sex ratio and genus diversity of soil free-living nematodes, and total abundance of bacteria and fungi, were measured during the hottest period of 2016. The impact of the birds’ activity on the soil biota was most notable in the upper soil layer and weaker in the lower soil layer. Soil properties such as alkalinity (pH) and conductivity, along with contents of ammonium, nitrate and phosphorus were found to be among the main drivers influencing prey–predator relationships in the observed soil habitat by altering the predation success of soil free-living nematodes. The observed nematode species were affected by the birds’ nesting and roosting activity, as reflected by an increasing proportion of common nematodes and the disappearance of rare species in the colonial birds’ habitats. The applied ecological indices showed that the different species of colonial birds can have different (stimulatory or inhibitory) impacts on the abundance and diversity of the soil biota, affecting the structure of soil free-living nematodes at the generic, trophic and sexual levels. Moreover, the soil ecosystem in the area of bird activity had a less complex food web, but with higher concentrations of nutrients than the uninhabited control area.

Waterbird Community in A Plantation Forest of An Industrial Area

Waterbird mostly were found in natural wetlands, nesting on mangrove trees. An unusual case was found in a human-made (plantation) forest in an automotive company within an industrial area. The objective of the research was to reveal the species and number of waterbirds that utilized the non-mangrove plantation forest and to record the number of nests and the nest tree preference. Waterbird census was conducted in June and July 2017 (beginning of rainy season) by direct total count of all individuals in the late afternoon (4-6pm). Waterbirds were able to use non-mangrove, plantation forest to roost and nest. On average, there were 4,482 individual resident waterbirds in the study area, consisted of 6 species and occupying 1.77 ha of semi-wetland area (inundated during rainy season), with an average roosting density of 9.4 nests/100m2. The dominant waterbird species were Intermediate Egret (30%), Little Egret (20%), and Black-crowned Night Heron (25%). Other observed species were Cattle Egret (15%), Javan Pond-Heron (5%), and Great Egret (5%). Breeding season was in progress and there were 535 active nests. Although the percentage of nests laid on M. leucadendra trees (49.9%) was similar to A. mangium (47.3%), statistical test suggested that M. leucadendra were highly preferred for nesting trees.

Nesting Dynamics of Four Ardeid Species at Subregional Scales: Recovery Rates after Sudden Major Declines in Nest Abundance

The functional roles of nesting heron species (Ardeidae) as top predators in regional wetland landscapes may be sensitive to variation in nesting abundances at subregional scales corresponding to available habitat for nesting and foraging within individual wetland subsystems. This study investigates the dynamics of annual nesting abundances of four ardeid species within 10 major wetland subsystems of the San Francisco Bay Area, California, USA, during 1991–2010. Interrupted time series analysis was used to measure impact and recovery rates related to sudden major declines in nesting abundance below selected thresholds of annual change. Year-to-year persistence of initial impacts was above 78% for Great Blue Herons (Ardea herodias) and Great Egrets (A. alba). Snowy Egrets (Egretta thula) recovered more quickly, with 63–66% annual carryover of initial impacts. The time required for 95% recovery averaged 18.8 years for Great Blue Heron, 13.0 years for Great Egret, 7.2 years for Snowy Egret, and 14.5 years for Black-crowned Night-Heron (Nycticorax nycticorax). Most of the major subregional declines in nest abundance were associated with impacts at a single colony site. The results highlight the significant effects of sudden major declines in nesting abundance on the status of ardeids within individual wetland systems across a larger regional wetland landscape.

Interspecific Broods at Two Heronries in Iran

Abstract. Four cases of interspecific mixed broods between Little Egrets (Egretta garzetta; n = 175), Cattle Egrets (Bubulcus ibis; n = 125), Squacco Herons (Ardeola ralloides; n = 25) and Black-crowned Night-Herons (Nycticorax nycticorax; n = 199) were recorded from 7 April to 16 August 2016 at two colonies in Iran. The rare occurrence of mixed broods and the low survival of the parasite chicks suggest that brood parasitism is not adaptive in the Ardeidae.

Wild waterfowl as potential vectors of Vibrio cholerae and Aeromonas species.

To study the hypothesis that migratory waterfowl are possible disseminators of Vibrio cholerae and Aeromonas. We monitored the presence of V. cholerae and Aeromonas in three wild waterfowl species. V. cholerae and Aeromonas species were isolated and identified from intestine samples of little egrets and black-crowned night herons. Only Aeromonas species were isolated from black-headed gulls. The majority of Aeromonas isolates were A. veronii. Twenty-three V. cholerae serogroups were identified. V. cholerae serogroup O1 was found in the intestine DNA extractions from four little egrets and black-crowned night herons; six birds carried cholera toxin subunit A gene. Wild waterfowl species may carry pathogenic V. cholerae O1 and non-O1 serogroups and Aeromonas species in their intestine. The migration of waterfowl is a potential mechanism for global distribution of V. cholerae and Aeromonas.

Morphometric Differences Between Sexes of Two Subspecies of Black-crowned Night-Heron (Nycticorax nycticorax) Using Discriminant Function Analysis

The objective of this study was to develop tools for distinguishing between sexes of the two Black-crowned Night-Heron (Nycticorax nycticorax) subspecies (N. n. obscurus and N. n. hoactli) using discriminant function analysis. Significant differences were found in length of the culmen, length of the bill from the gape, and length of the wing chord between the sexes of each subspecies, with males being larger than females. The resulting discriminant functions were able to differentiate between the sexes of each studied subspecies and between subspecies after determining the sex of the individuals (with a correct classification of 77.8% for females and 97.8% for males). In females, all morphometrics were greater for N. n. obscurus than N. n. hoactli; this was also the case for males, except for bill width, which was greater in N. n. hoactli. Wing chord length was the most useful measurement for constructing the discriminant functions. External morphometrics are a valuable tool not only for discriminating between N. n. hoactli and N. n. obscurus but also for sexing these subspecies.

Rapid departure of Roseate Terns (Sterna dougallii) following large-scale nest failure

ABSTRACT Nest failure of most pairs of Roseate Terns (Sterna dougallii) at Falkner Island, Connecticut, in 2002–2003 (due mainly to predation by Black-crowned Night-herons [Nycticorax nycticorax]) was followed by the rapid departure of many of the failed individuals in both years. Nine failed pairs (16.7%) stayed while 40 (74.1%) of 54 unsuccessful pairs left within 2 d following nest failure in 2002, and 7 pairs (21.9%) stayed while 25 (78.1%) of 32 unsuccessful pairs left within 2 d in 2003. Individuals that departed this colony site by the end of June likely had time to prospect and renest at another colony site in the same year, and individuals that successfully renested at another colony site could have shown reduced colony-site fidelity to Falkner Island in subsequent years.

Dietary Segregation of Four Ardeid Species Breeding in Anzali International Wetland, Northern Iran

Abstract. The nestling diets of four heron species breeding on a small forestry islet in Anzali, Iran, were investigated to determine the dietary segregation among sympatric breeders. Regurgitated samples from Black-crowned Night-Herons (Nycticorax nycticorax), Little Egrets (Egretta garzetta), Cattle Egrets (Bubulcus ibis) and Squacco Herons (Ardeola ralloides) were collected during the breeding season from 23 May to 16 August 2016. A total of 1,606 prey items were identified representing 39 prey categories from nine different classes. Differences were detected among these four ardeid species for the percentage of each prey category. Fish dominated the regurgitates of the Blackcrowned Night-Heron (67%; n = 43 samples), Little Egret (45%; n = 33 samples) and Squacco Heron (53%; n = 10 samples), whereas arachnids and insects combined (53% and 40%, respectively, based on total number of individuals) and insects (61.9% based on weight) were the most common prey items for the Cattle Egret. Although fish items...

Long-Term Changes in Food Intake by Grey Herons (Ardea cinerea), Black-Crowned Night-Herons (Nycticorax nycticorax) and Little Egrets (Egretta garzetta) Foraging in Rice Fields in Italy

In northwestern Italy, traditional rice cultivation using permanent flooding has been replaced by cultivation that uses a reduced water depth and a shortened submersion period. Prey availability for the numerous herons and egrets using this intensive rice cultivation region changed as well, with a diminution of amphibians and an increase of crayfish (Procambarus clarkii) and oriental weatherfish (Misgurnus anguillicaudatus). The prey intake in 2014 was compared with data available for 1987 for the three most common species of waterbirds that forage in the paddies. Total biomass intake by Grey Herons (Ardea cinerea) feeding in the paddies decreased from 28 g dry mass/min in 1987 to 7 g in 2014, and by Black-crowned Night-Herons (Nycticorax nycticorax) from 8 g to 5 g, while the intake by Little Egrets (Egretta garzetta) remained similar (12 and 13 g in 1987 and 2014, respectively). The observed levels of prey intake allowed breeding Grey Herons to meet their energy needs by feeding exclusively in the rice paddies in 1987, but not in 2014. The other two study species could not meet their daily requirements for successful breeding by feeding in the paddies only, either in 1987 or 2014. Yet the three species bred successfully in the study area, and their reproductive output remained stable both in 1987 and 2014. Successful breeding was probable by the three species foraging in other habitats, such as rivers, small natural wetlands and irrigation canals, in the region.

Nest position, breeding success and diet of the Black-crowned Night Heron, Nycticorax nycticorax in the Anzali Wetland, Northern Iran (Aves: Ardeidae)

Breeding ecology of the Black-crowned Night Heron (Nycticorax nycticorax) was studied in a mono-specific colony in the Anzali wetland, Northern Iran during the breeding season of 2016. The breeding period lasted from mid-May to late July. The average clutch size was 3.1±0.6 eggs and the breeding success 77.6%. No significant differences were found between nests built on trunks and those built on branches of trees. The clutch size and breeding success appeared to be independent of the structural variables of the nesting site (diameter of trees, height from the ground, height of nests from the canopy, nest number per tree, location of nests on trunks and branches). No significant difference was found between the timing of the start of incubation and the height of nests above the ground. The average vertical and horizontal distances between nests was one metre. Fish, particularly Carassius gibelio, dominated the diet of the nestlings.

Human exposure to PCDDs and their precursors from heron and tern eggs in the Yangtze River Delta indicate PCP origin

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are highly toxic to humans and wildlife. In the present study, PCDD/Fs were analyzed in the eggs of whiskered terns (Chlidonias hybrida), and genetically identified eggs from black-crowned night herons (Nycticorax nycticorax) sampled from two lakes in the Yangtze River Delta area, China. The median toxic equivalent (TEQ) of PCDD/Fs were 280 (range: 95–1500) and 400 (range: 220–1100) pg TEQ g−1 lw (WHO, 1998 for birds) in the eggs of black-crowned night heron and whiskered tern, respectively.Compared to known sources, concentrations of PCDDs relative to the sum of PCDD/Fs in bird eggs, demonstrated high abundance of octachlorodibenzo-p-dioxin (OCDD), 1,2,3,4,6,7,8-heptaCDD and 1,2,3,6,7,8-hexaCDD indicating pentachlorophenol (PCP), and/or sodium pentachlorophenolate (Na-PCP) as significant sources of the PCDD/Fs. The presence of polychlorinated diphenyl ethers (PCDEs), hydroxylated and methoxylated polychlorinated diphenyl ethers (OH- and MeO-PCDEs, known impurities in PCP products), corroborates this hypothesis. Further, significant correlations were found between the predominant congener CDE-206, 3′-OH-CDE-207, 2′-MeO-CDE-206 and OCDD, indicating a common origin.Eggs from the two lakes are sometimes used for human consumption. The WHO health-based tolerable intake of PCDD/Fs is exceeded if eggs from the two lakes are consumed regularly on a weekly basis, particularly for children. The TEQs extensively exceed maximum levels for PCDD/Fs in hen eggs and egg products according to EU legislation (2.5 pg TEQ g−1lw). The results suggest immediate action should be taken to manage the contamination, and further studies evaluating the impacts of egg consumption from wild birds in China. Likewise, studies on dioxins and other POPs in common eggs need to be initiated around China.

Observations of Indirect Filial Cannibalism in Response to Nest Failure of Black-crowned Night-Herons (Nycticorax nycticorax)

ABSTRACT During 2011, four separate instances of indirect filial cannibalism, whereby adults consumed their young that died from unknown causes, were observed using video-monitoring techniques in a nesting colony of Black-crowned Night-Herons (Nycticorax nycticorax) on Alcatraz Island. Though they were not observed actively killing their young, in all four observations adult Black-crowned Night-Herons consumed their young following death (i.e., indirect filial cannibalism). We could not determine cause of chick mortality, but parental neglect was likely a contributing factor in at least two instances. Indirect filial cannibalism is not commonly documented among birds, and understanding how cannibalism contributes to nest failure can help researchers better understand factors that limit nesting populations.