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Abstract Colonial waterbirds, a major biodiversity element occurring in the core of ultra-anthropized Europe, are ideal indicators of the wellness of inland wetlands. Nonetheless, there is a critical knowledge gap in their trend and population status. We present an uninterrupted 47 years-long dataset of the breeding populations of 12 species of colonial waterbirds (Ardeidae, Phalacrocoracidae, Plataleidae, Threskiornitidae) throughout a 58,000 km2 agricultural region in the higher Po basin (NW Italy). A trained team of collaborators censused with standardized field techniques the number of nests of each species at 419 colonies in the 1972–2018 period, summing up a total of 236,316 records. Data cleaning and standardization were performed for each census year, ensuring robust and consistent data. This dataset is among the largest ever collected for a guild of European vertebrates. It has already been used to describe the factors influencing population trends, and still offers opportunities to explore a wide range of key ecological processes such as biological invasions, global change consequences and biodiversity impact of agricultural practices.

The breeding populations of colonial herons, egrets and allied waterbirds in Northwestern Italy increased since 1972, when a long-term monitoring was initiated, up to the end of the 20° century. Populations of continental importance for some heron species were concentrated mostly in the district of intensive rice cultivation, where the paddies offered wide foraging opportunities. After 2000, new cultivation techniques caused a progressive reduction in paddy flooding. We found a significant relationship between the post-2000 decrease in the number of nests of the three most abundant species of waterbirds, Grey Heron, Little Egret and Black-crowned Night-heron, and the diminishing extent of paddy flooding estimated on satellite-derived images. On the other hand, outside the paddies district the same three species continued to increase or remained mostly stable. The recent agronomic changes in the paddies of Northwestern Italy compromise their role as surrogates of natural wetlands and their importance for environmental conservation. The spread of dry rice fields, and the consequent loss of their value for conservation of aquatic biodiversity, call for a revision of the regulations and incentives to farmers under the Common Agriculture Policy by the European Union and by local authorities. Return to early-submerged rice fields and adoption of environmental-friendly practices, such as the creation of compensatory wetlands, should become mandatory for rice to maintain its status as “green” crop.

Abstract The spreading of invasive species in new continents can vary from slow and limited diffusion to fast colonisations over vast new areas. We studied the sacred ibis Threskiornis aethiopicus along a 31-year period, from 1989 to 2019, with particular attention to the first area of release in NW Italy. We collected data on species distribution through observations by citizen science projects, population density by transects with distance method, breeding censuses at colonies, and post breeding censuses at roosts. The birds counted at winter roosts in NW Italy increased from a few tens up to 10,880 individuals in 2019. Sacred ibises started breeding in 1989, with a single nest in north-western Italy. The number of breeders remained very low until 2006, when both overwintering and breeding sacred ibises started to increase exponentially and expand their range throughout northern Italy with isolated breeding cases in central Italy. In 2019, the number of nests had increased to 1249 nests in 31 colonies. In NW Italy, the density of foraging birds averaged 3.9 ind./km2 in winter and 1.5 ind./km2 in the breeding period, with a mean size of the foraging groups of 8.9 and 2.1 birds respectively. Direct field observations and species distribution models (SDM) showed that foraging habitats were mainly rice fields and wetlands. A SDM applied to the whole Italian peninsula plus Sardinia and Sicily showed that the variables best related to the SDM were land class (rice fields and wetlands), altitude, and the temperature seasonality. The areas favourable for species expansion encompass all the plains of Northern Italy, and several areas of Tuscany, Latium, Sardinia, and Apulia.

The systematics of the cophyline microhylid frog genera Plethodontohyla and Rhombophryne have long been intertwined, and their relationships have only recently started to become clear. While Rhombophryne has received a lot of recent taxonomic attention, Plethodontohyla has been largely neglected. Our study is a showcase of just how complex the taxonomic situation between these two genera is, and the care that must be taken to resolve taxonomic conundrums where old material, multiple genus transitions, and misattribution of new material obfuscate the picture. We assessed the identity of the historic names Dyscophus alluaudi (currently in the genus Rhombophryne), Phrynocara laeve and Plethodontohyla laevis tsianovohensis (both synonyms of Rhombophryne alluaudi) based on an integrative taxonomic approach harnessing genetics, external morphology, osteological data obtained via micro-Computed Tomography (micro-CT) and bioacoustics. We show that (1) the holotype of Dyscophus alluaudi is a member of the genus Plethodontohyla; (2) the Rhombophryne specimens from central Madagascar currently assigned to Rhombophryne alluaudi have no affinity with that species, and are instead an undescribed species; and (3) Phrynocara laeve and Dyscophus alluaudi are not synonymous, but represent closely related species, whereas Plethodontohyla laevis tsianovohensis is tentatively confirmed as synonym of D. alluaudi. We resurrect and re-describe Plethodontohyla laevis, and re-allocate and re-describe Plethodontohyla alluaudi on the basis of new and historic material.

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The importance of targeting ecological and evolutionary processes in reserve design has been widely acknowledged in the literature but rarely implemented on islands. Using Socotran reptiles as models, we aim to relate richness of widespread and restricted-range species directly with landscape variables and to compare the impact of setting conservation targets for lineages versus species. Socotra Island is a UNESCO Natural World Heritage Site, containing high levels of endemism in relation to its area, especially of reptiles, the vertebrates with the most comprehensive available genetic data. We predicted the occurrences of reptile species using distribution models and used a novel approach to interpolate maps of spatial phylogenetic patterns. Patterns of intra and interspecifc diversity and differences between spatial outputs of lineage and species richness were related to eco-geographic variables. We evaluated differences in target achievement for each conservation unit within protected areas (PAs) under the current Zoning Plan (ZP) using gap and reserve design analyses. Although intraspecific richness was strongly correlated with interspecific richness, differences in their spatial distribution reached ~30% in some areas. Differences were more pronounced for wide-ranging than restricted-range taxa. Gap analysis indicates that most conservation units are under-represented in sanctuaries and that intra and interspecific richness were significantly higher outside PAs. This work will guide local-scale conservation planning as the ZP is due to be re-evaluated. This is one of the few studies on islands using genetic data from an entire class of vertebrates to incorporate lineage diversity in reserve design. This study provides an alternative methodological framework for supporting the use of landscape and genetic tools in reserve design, circumventing the use of phylogenetic distances and deterministic spatial interpolation of lineage diversity that can be widely applied to other systems.

In questo lavoro viene riportato un elenco commentato degli uccelli noti per la provincia di Novara (1.340 km2) aggiornato al 31/12/2016 e vengono forniti dati di sintesi relativi alle attività di monitoraggio condotte in anni recenti (2009-2016). I dati sono stati raccolti sia attraverso revisione bibliografica sia attraverso attività di ricerca diretta sul campo. L’avifauna della provincia di Novara annovera o ha annoverato (dal 1860 al 2016) 304 specie delle quali 135 nidificanti certe o probabili in tempi recenti (dopo il 2000), 85 di interesse comunitario (Allegato I della Direttiva “Uccelli”), 116 SPEC - Species of European Conservation Concern secondo BirdLife International e 53 inserite nella European Red List of Birds. L’area è di importanza europea e/o nazionale per la nidificazione di specie di interesse conservazionistico quali Egretta garzetta (650-1.100 nidi), Nycticorax nycticorax (200-300 nidi), Botaurus stellaris (5-7 maschi cantori), Ciconia nigra (1-2 coppie), Ciconia ciconia (4-6 coppie), Himantopus himantopus (300-500 coppie), Vanellus vanellus (500-600 coppie), Columba oenas (20-30 coppie), nonché per la migrazione di Philomachus pugnax (5.000-7.000 ind.) e Tringa glareola (500-1.500 ind.). Negli ultimi anni (2009-2016) si segnalano in particolare: la nidificazione accertata per la prima volta nel Novarese di Ardea alba, Galerida cristata e Lullula arborea; il ritorno di Burhinus oedicnemus e Chlidonias niger in periodo riproduttivo dopo decenni di assenza; la colonizzazione da parte di Dryocopus martius degli ambienti forestali di collina e di pianura.

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Few DNA barcoding studies of squamate reptiles have been conducted. Due to the significance of the Socotra Archipelago (a UNESCO Natural World Heritage site and a biodiversity hotspot) and the conservation interest of its reptile fauna (94% endemics), we performed the most comprehensive DNA barcoding study on an island group to date to test its applicability to specimen identification and species discovery. Reptiles constitute Socotra's most important vertebrate fauna, yet their taxonomy remains under-studied. We successfully DNA-barcoded 380 individuals of all 31 presently recognized species. The specimen identification success rate is moderate to high, and almost all species presented local barcoding gaps. The unexpected high levels of intra-specific variability found within some species suggest cryptic diversity. Species richness may be under-estimated by 13.8-54.4%. This has implications in the species' ranges and conservation status that should be considered for conservation planning. Other phylogenetic studies using mitochondrial and nuclear markers are congruent with our results. We conclude that, despite its reduced length (663 base pairs), cytochrome c oxidase 1, COI, is very useful for specimen identification and for detecting intra-specific diversity, and has a good phylogenetic signal. We recommend DNA barcoding to be applied to other biodiversity hotspots for quickly and cost-efficiently flagging species discovery, preferentially incorporated into an integrative taxonomic framework.

The intensive rice cultivation area in northwestern Italy hosts the largest surface of rice paddies in Europe, and it is valued as a substantial habitat for aquatic biodiversity, with the paddies acting as a surrogate for the lost natural wetlands. The extent of submerged paddies strictly depends on crop management practices: in this framework, the recent diffusion of rice seeding in dry conditions has led to a reduction of flooded surfaces during spring and could have contributed to the observed decline of the populations of some waterbird species that exploit rice fields as foraging habitat. In order to test the existence and magnitude of a decreasing trend in the extent of submerged rice paddies during the rice-sowing period, MODIS remotely-sensed data were used to estimate the extent of the average flooded surface and the proportion of flooded rice fields in the years 2000–2016 during the nesting period of waterbirds. A general reduction of flooded rice fields during the rice-sowing season was observed, averaging − 0.86 ± 0.20 % per year (p-value < 0.01). Overall, the loss in submerged surface area during the sowing season reached 44 % of the original extent in 2016, with a peak of 78 % in the sub-districts to the east of the Ticino River. Results highlight the usefulness of remote sensing data and techniques to map and monitor water dynamics within rice cropping systems. These techniques could be of key importance to analyze the effects at the regional scale of the recent increase of dry-seeded rice cultivations on watershed recharge and water runoff and to interpret the decline of breeding waterbirds via a loss of foraging habitat.

Birds are among the most important biological components of wetlands. They play a key role in their ecology and are an important cultural resource for the public, in part because some species can be legally hunted. The conservation of waterbirds is especially important in terms of land use planning, in light of their ecological, cultural, and economic value. Here we summarize the results of wintering waterbirds censuses carried out in Lombardy between 2002 and 2013, using the standardized International Waterbird Census methodology. Our goals were to identify priority sites for waterbirds; estimate population sizes; define demographic trends; and provide a technical framework for making administrative and legislative decisions on the management and conservation of wetlands and their bird species. Lombardy hosts substantial numbers of wintering waterbirds, and many of its wetlands qualify as areas of conservation interest under Ramsar Convention criteria, as they host >1% of the Italian population of one or more species. Trends for the 20 species of highest conservation or hunting interest showed stable or increasing populations in most cases, with the exception of Black-necked Grebe, Common Pochard, and Eurasian Coot, which instead decreased in 2002-2013. The favourable population trends for most species suggest that the ecological status of Lombardy’s wetlands is essentially stable, but it could be improved by simple measures to improve the natural value of the shorelines and bottoms of major lakes and flooded gravel pits. Hunting was one of the main factors affecting the distribution and abundance of wintering waterbirds, which concentrate in protected areas - over 50% of all birds, rising to over 70% for species of conservation interest concentrate there, despite the fact that protected areas only account for 43% of sites surveyed. Overall, protected areas hosted bird densities that were almost seven times higher than those managed primarily for hunting, while mixed-use areas hosted intermediate densities of birds. The presence of protected and unprotected areas within the same wetland mitigates the effects of hunting on bird populations and species diversity, and may help maintain adequate conditions for their conservation.

Allochthonous water frogs (gen. Pelophylax) have been repeatedly introduced in several European countries, causing dramatic consequences for the conservation of indigenous taxa. In Italy, invasive populations are known for northern regions, where they were introduced mainly for edible and scientific purposes. Here, we report the first detection of an alien population of water frogs in Central Italy, along the Resina valley (Umbria). Genetic analysis of the mitochondrial ND3 gene polymorphism assigned some specimens to two different Pelophylax ridibundus clades widespread in Central and Eastern Europe. By contrast, two samples matched the mitochondrial DNA (mtDNA) sequence of Pelophylax lessonae bergeri, an autochthonous taxon widespread in Central Italy, suggesting possible hybridization between alien and indigenous frogs. Finally, the specific haplotype of Pelophylax shqipericus, the Albanian Pool Frog, was also identified according to mtDNA polymorphism. This record, firstly reported for Italy, poses concerns for the conservation of this cryptic taxon, suggesting that international water frog trade may involve also particularly endangered species.

Photoperiodic responses are major factors entraining circannual life-cycles, functioning to adaptively synchronize annual routines to seasonal fluctuations in ecological conditions. Photoperiodism in physiology and behaviour is enforced by genes, including the vertebrate Clock orthologues, which are associated, for example, with phenology of migration in fish and breeding in birds. However, the role of Clock in photoperiodic plumage molt processes is unknown. We analyzed variation in molt schedules in relation to Clock genotype, using the long-distance migratory barn swallow (Hirundo rustica) as a model and by identifying males and females using molecular sexing techniques. Consistently with previous studies, we found one very common (Q7) and two rare (Q6, Q8) variants of a functionally significant Clock polyglutamine repeat. Molt schedules of primary wing feathers of swallows during their wintering period in Nigeria differed among Clock genotypes: rare (1.1%) Q7/Q8 heterozygotes had significantly delayed molt compared to the other genotypes. Molt schedules did not differ between males and females, and no differential association between molt and Clock in relation to sex emerged. The same rare Clock genotype that exhibited delayed breeding in Europe was here found to delay molt in Africa. Though based on a limited number of Q7/Q8 individuals from an otherwise very large sample, these novel results suggest that Clock is involved in the photoperiodic control of both molt and breeding, potentially also via reciprocal carry-over effects. If confirmed in species with higher Clock polymorphism, present results may have far-reaching consequences for the study of photoperiodic control of molt and expression of annual routines.

Female common wall lizards (Podarcis muralis) typically reproduce annually and lay more than one clutch per season. In this study, we tested whether females store sperm between clutches and between years by manipulating mating opportunities of females through appropriate experiments. Our results revealed that females are definitely unable to store sperm for medium or long-term, suggesting they necessary need to repeatedly mate with males to fertilize their eggs. Finally, by comparing our results to other similar multi-clutched species, we conclude that sperm storage probably does not constitute a selective advantage for species with a promiscuous reproductive system based on multiple mating in populations with high densities.

In species where females mate promiscuously, the reproductive success of males depends both on their ability to acquire mates (pre-copulatory sexual selection) and ability of their ejaculates to outcompete those of other males (post-copulatory sexual selection). Sperm competition theory predicts a negative relationship between investment in body traits favouring mate acquisition (secondary sexual characters, SSCs) and investment in ejaculate size or quality, due to the inherent costs of sperm production. In contrast, the phenotype-linked fertility hypothesis posits that male fertilizing efficiency is reliably reflected by the phenotypic expression of male SSCs, allowing females to obtain direct benefits by selecting more ornamented males as copulation partners. In this study, we investigated the relationships between male SSCs and size and quality (viability and longevity) of ejaculates allocated to females in mating trials of the freshwater crayfish Austropotamobius italicus. We showed that the relative size of male weapons, the chelae, was negatively related to ejaculate size, and that chelae asymmetry, resulting from regeneration of lost chelipeds, negatively covaried with sperm longevity. Moreover, males allocated more viable sperm to mates from their own rather than different stream of origin. Our findings thus suggest that, according to sperm competition theory, pre-copulatory sexual selection for large weapons used in male fighting may counteract post-copulatory sperm competition in this crayfish species, and that investment in cheliped regeneration may impair ejaculate quality.

A new endemic gecko of the genus Hemidactylus is described from Socotra Island (Yemen). It is a rupicolous species characterized by: medium-large size (SVL up to 60 mm), back with large trihedral, raised, strongly keeled tubercles intermixed with small granular scales, males with 6-10 preanal pores arranged in two short rows separated by 2-3 scales. In East Africa, Arabia, the Middle East and India the only other tuberculated Hemidactylus with preanal pores arranged on two separate rows is the Somali H. granchii Lanza, 1978, which differs for the comparatively deeper and shorter head, the nostril separated from the first upper labial, less preanal pores, less upper and lower labials, more tubercles at midbody and more lamellae under the inner toe.

Photographic identification is a promising marking technique alternative to the toe-clipping, but is time consuming, particularly when a large number of individuals is involved. For this reason several authors had frequently preferred the toe-clipping. In this study we analysed the black spot pattern of ventral scales of wall lizards (Podarcis muralis) and we showed that photographic identification is an effective method for recognizing individuals, and the error of this technique is much less than that of the toe-clipping arising from natural toe loss. Moreover, the numerically encoding of the black spot pattern may radically reduce the time needed to compare the pictures of large samples of individuals, solving one of the more important obstacle against the use of photographic identification.

A new species of the genus Hemidactylus is described on the basis of two specimens (an adult male and an adult female) collected in 2005 in rocky and sandy habitat of the semiarid climatic region on the eastern shore of Lake Turkana (Kenya). It is a medium-sized Hemidactylus (SVL from 40 to 50 mm) distinguished from all other species by a unique combination of characters. The back is covered by large, trihedral, strongly keeled tubercles, intermixed with a few small, irregular shaped granules, forming 14 quite regular transverse rows from axilla to groin; nostrils contact the rostral, first supralabial, 1 enlarged internasal and 2-3 postnasals; the dorsal half of the rostral scale is divided longitudinally; there are 6 lamellae under the first toe and 10 under the 4th toe; male with 8 precloacal pores; female without pores. The dorsal colour pattern is very distinctive, consisting of four transverse bands, bordered with dark margins. The types are housed in the Herpetological Collections of the Museo di Storia Naturale of the University of Pavia and in the National Museums of Kenya (Nairobi).

La stima dell'abbondanza di popolazione rappresenta un aspetto di fondamentale importanza ed elevata complessità nell'ecologia delle popolazioni animali. I metodi applicabili agli studi che prevedono cattura, marcatura e ricattura (CMR) sono stati analizzati criticamente da Nichols e Pollock, i quali raccomandano l'adozione di stimatori basati su modelli probabilistici anziché i più diffusi metodi enumerativi. Scopo del presente lavoro è di confrontare le stime di abbondanza di popolazioni di Apodemus sylvaticus e Clethrionomys glareolus desunte da modelli probabilistici e relativi estimatori rispetto a metodi enumerativi quali il Minimum Number Alive (MNA). Fra il mese di aprile 2002 e febbraio 2003 le popolazioni di topo selvatico e arvicola rossastra sono state campionate mediante metodi CMR. L'area di studio è rappresentata dalla RN "Monticchie" di Somaglia (LO); la griglia di cattura era costituita da 98 trappole disposte a 10 m. Le trappole erano innescate con semi di girasole e controllate giornalmente. Gli individui catturati marcati e rilasciati dopo la raccolta di dati biometrici. I dati di popolazione sono stati elaborati adottando il "robust design" di Pollock. Il periodo di cattura è stato diviso in sessioni primarie (mesi) e secondarie (settimane); Φ (sopravvivenza) e N (abbondanza) sono stati calcolati rispettivamente sulla base dei dati delle sessioni primarie e secondarie utilizzando i software Jolly e Capture. Stime indipendenti di N sono state ricavate da Jolly e applicando il MNA. L'analisi dei dati mostra che la precondizione di chiusura demografica delle popolazioni durante le sessioni secondarie di cattura è soddisfatta nell'82% dei casi. I modelli selezionati da Capture, e i relativi estimatori dell'abbondanza sono in prevalenza, per entrambe le specie, Mo (null) e Mh (jackknife). Il confronto fra i modelli di tipo enumerativo e di tipo probabilistico dimostra che le stime di N ottenute mediante il primo metodo, anche se maggiormente intuitive e di semplice calcolo, sottostimano, in percentuali variabili dal 48,7% al 64,7% l'abbondanza della popolazione campionata. La differenza della stima di N ottenuta mediante i due metodi è statisticamente significativa (Test t di Student; P

Females may invest more in reproduction if they acquire mates of high phenotypic quality, because offspring sired by preferred partners may be fitter than offspring sired by non-preferred ones. In this study, we tested the differential maternal allocation hypothesis in the freshwater crayfish, Austropotamobius italicus, by means of a pairing experiment aimed at evaluating the effects of specific male traits (body size, chelae size and chelae asymmetry) on female primary reproductive effort. Our results showed that females laid larger but fewer eggs for relatively small-sized, large-clawed males, and smaller but more numerous eggs for relatively large-sized, small-clawed males. Chelae asymmetry had no effects on female reproductive investment. While the ultimate consequences of this pattern of female allocation remain unclear, females were nevertheless able to adjust their primary reproductive effort in relation to mate characteristics in a species where inter-male competition and sexual coercion may mask or obscure their sexual preferences. In addition, our results suggest that female allocation may differentially affect male characters, thus promoting a trade-off between the expression of different male traits. [ABSTRACT FROM AUTHOR]

The courtship and mounting behavior of promiscuous tortoises is based on a multiple signaling system that includes visual, olfactory, tactile, and acoustic signals. Vocalizations related to mounting seem to be particularly intriguing because tortoises vocalize mainly at this time. Vocalizations and courtship behavior might be costly for males, and if these costs increase differentially for different males, then the potential exists for vocalizations and displays to reveal male individual quality on which females could base their mate choice. In the present study, by using individuals breeding in seminatural enclosures, we experimentally investigated whether the mounting call of male Hermann's tortoises (Testudo hermanni) represents a relevant stimulus to both males and females. We also looked for potential preference toward different acoustic stimuli in order to determine which call features, if any, played a role in attracting potential partners or deterring rivals. Females were sensitive to call playback, whereas males apparently paid little attention to playback. In addition, females showed a significant preference toward high-pitched calls emitted at high rate. Also, females exhibited a strong tendency toward short-duration calls. Because call rate is related to hematocrit in Hermann's tortoise males, by responding to fast-rate calls females are also choosing high-quality partners as sires of their offspring. This is the first study in which an attractive function of tortoise vocalizations has been documented. [ABSTRACT FROM AUTHOR]

61 eggs of night heron (Nycticorax nycticorax) were collected in 2000 in Yuantouzhu of Tai lake, China. The breeding birds were divided into three groups by age, namely two, three, four years. The residues of 15 polychlorinated biphenyl congeners in eggs were studied. 15 congeners were found in all egg samples, and PCB118 at the highest level, PCB87, PCB101 and PCB153 at second levels. Total residues of the 4 congeners occupied about 75%-85% of sum 15 congeners residues found in eggs. It was obviously that residues of congeners containing 5-6 chlorine atoms were more than others in eggs. Residues of PCBs in eggs increased with age of breeding birds. The total PCBs concentration in eggs of four years group were higher than that of three years group, two years group by 47.5% and 60.9% respectively. Different from the result of the similar studies in European countries, USA and Japan: the residue of PCB153 is the highest, it was found that in this study the residue of PCB118 is the highest in eggs, which is about 30% of the total PCBs residues, while the PCB153 17% only.

There were four species of Ardeidae in Tai Lake. The dominant vegetations in the habitat were Pinus massoniana, Cinnamomum hupehanum, Quercus acutissema, Ulmus prmila and Myrica rubra, which were suitable for Egretta garzetta to make nests. The area of the habitat was about 7 hm2, where there were totally 4200 Egretta garzetta nests with the density of 0.38 nest per tree in average. Studies on Egretta garzetta breeding ecology showed that the incubating time was 19-21 days, the average egg weight was 23.9 +/- 4.0 g(n = 41), and the average egg size was 44.5 +/- 4.1 mm x 32.6 +/- 4.9 mm(n = 41). The mean clutch size and brood size were 5.02(2-8) and 3.86(2-7), respectively, and the hatching rate was 84.25%. The measurements of Egretta garzetta nestling tarsus did not show any asymmetry (P > 0.05). Egretta garzetta fed mainly on small fish and shrimps in Tai Lake. The analysis results of Tai Lake samples showed that the pollutants including HCH, HCB, cyclodience, DDTs (DDT, DDE and DDD), PCBs, Cr, Hg and Pb in Egretta garzetta eggs were detected except Cd, and these pollutants accumulated through prey chain from sediments and preys to nestlings. Comparing samples from Tai Lake and those from Poyang Lake as relatively unpolluted area, only the concentration of DDTs residues was higher than 2 micrograms.g-1 in both lakes, and the other residues from Tai Lake like organochlorine insecticides, PCBs and heavy metals were all lower than those from Poyang Lake, and did not affect the development and breeding success of Egretta garzetta at present.