Common Terns Research Articles

First Description of Mergibacter septicus Isolated from a Common Tern (Sterna hirundo) in Germany.

Mergibacter septicus (M. septicus), previously known as Bisgaard Taxon 40, is a recently described species within the Pasteurellaceae family. In this study, we present a M. septicus strain isolated from a common tern (Sterna hirundo) chick that died just after fledging from the Banter See in Wilhelmshaven, Germany. The recovered M. septicus strain underwent microbiological phenotypic characterization, followed by whole genome sequencing on Illumina and Nanopore platforms. Phenotypically, M. septicus 19Y0039 demonstrated resistance to colistin, cephalexin, clindamycin, oxacillin, and penicillin G. The genome analysis revealed a circular 1.8 Mbp chromosome without any extrachromosomal elements, containing 1690 coding DNA sequences. The majority of these coding genes were associated with translation, ribosomal structure and biogenesis, followed by RNA processing and modification, and transcription. Genetic analyses revealed that the German M. septicus strain 19Y0039 is related to the American strain M. septicus A25201T. Through BLAST alignment, twelve putative virulence genes previously identified in the M. septicus type strain A25201T were also found in the German strain. Additionally, 84 putative virulence genes distributed across nine categories, including immune modulation, effector delivery system, nutrition/metabolic factors, regulation, stress survival, adherence, biofilm, exotoxin, and motility, were also identified.

Nest success of ground-nesting ducks in the wetlands of Great Salt Lake, Utah.

The number of ground-nesting ducks in the wetlands of Great Salt Lake, Utah has drastically decreased in the past few decades. A potential cause for this decline is the increase of predator species and their abundances, which has caused most nests to fail from depredation. Ground-nesting ducks may be able to reduce the risk of nest depredation by selecting nest sites where local physical structures or vegetation provides olfactory or visual concealment. To test this, we used logistic exposure models to look at the effect of nest-site characteristics on daily survival rates (DSRs) of nests during 2019, 2020, and 2021 in the wetlands of Great Salt Lake, Utah. We found 825 duck nests including 458 cinnamon teal (Spatula cyanoptera), 166 mallards (Anas platyrhynchos), and 201 gadwalls (Mareca strepera). DSRs were 0.9714 ± 0.0019 in 2019, 0.9282 ± 0.0049 in 2020, and 0.8274 ± 0.0185 in 2021. Survival rates varied among years but not among duck species. Striped skunks (Mephitis mephitis) and raccoons (Procyon lotor) were responsible for 85% of depredated nests. Nests located near other duck nests had higher DSRs than more dispersed nests. Neither visual nor olfactory characteristics correlated with increased DSRs based on AICc analysis. Nests located inside a mixed nesting colony of American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), and common terns (Sterna hirundo) had higher DSRs than duck nests outside the colony. Increased nesting densities of ducks and other colonial waterbirds had the greatest impact on nesting success. Increased nest density may be encouraged through early spring green-up.

Common Terns Sterna hirundo and Roseate Terns Sterna dougallii frequently rest on the sea surface in winter quarters and during migration

ABSTRACT Capsule Common Terns Sterna hirundo and Roseate Terns S. dougallii rarely rest on the sea surface during the breeding season but frequently do so in winter and on migration. Aims To investigate the behaviour of Common and Roseate Terns throughout the annual cycle using immersion sensors. Methods We analyzed data from immersion sensors attached to 11 Common Terns and 6 Roseate Terns that bred in the northeastern USA and wintered either on the north or east coasts of South America, to investigate temporal patterns of resting on saltwater throughout the annual cycle. Results Both species of tern rarely contacted salt water during the breeding season, except when bathing or plunge-diving, but in winter they spent several hours each day resting on the sea surface. This resting was most frequent around midday and least frequent in early mornings and late afternoons. Night-time immersion varied widely among individuals but terns wintering in eastern Brazil were less likely to spend the night on the sea surface than those wintering on the north coast of South America. We suggest that this reflected the availability of dry-land roosting sites. Conclusion Our results are consistent with and extend studies from Europe, confirming that although Common and Roseate Terns spend very little time resting on the sea surface in the breeding season, this behaviour is frequent during migration and wintering periods.

Low heritability of social phenotypes in a nonpasserine waterbird.

Most behavioral traits are known to be weakly heritable, possibly due to their extreme complexity and flexibility. Despite this general pattern, within-species variation in avian colony size choice has been reported to have a strong additive genetic component, but we are aware of no attempts to assess the heritability of avian sociality at the finer spatial scale. Here, we used an animal model and parent-offspring regression to quantify additive genetic variance in social phenotype (local nesting density) in a nonpasserine waterbird, the common tern Sterna hirundo. For this purpose, we used a novel experimental framework, where variation in the social environment was generated by providing birds with artificial patches of attractive nesting substrate that markedly varied in size. During 2011-2019, we collected data on social preferences for either low or high nesting density in over 250 individuals, either kin (mostly parent-offspring relationships) or non-kin recorded breeding multiple times across years. All heritability estimates of local nesting density were low (<0.10), irrespectively of fixed effects (sex and year) included in the models, data used in the modeling (all individuals vs. early recruits), or methodological approach (animal model vs. parent-offspring regression). We conclude that avian sociality, as measured at the local scale, may be much less heritable than colony size choice, as measured at the landscape level. Our study adds to the understanding of additive genetic variance in avian behavior, and it underlines a scale dependency in the heritability of behavioral traits.

Micro-evolutionary response of spring migration timing in a wild seabird.

In the context of rapid climate change, phenological advance is a key adaptation for which evidence is accumulating across taxa. Among vertebrates, phenotypic plasticity is known to underlie most of this phenological change, while evidence for micro-evolution is very limited and challenging to obtain. In this study, we quantified phenotypic and genetic trends in timing of spring migration using 8,032 dates of arrival at the breeding grounds obtained from observations on 1,715 individual common terns (Sterna hirundo) monitored across 27 years, and tested whether these trends were consistent with predictions of a micro-evolutionary response to selection. We observed a strong phenotypic advance of 9.3 days in arrival date, of which c. 5% was accounted for by an advance in breeding values. The Breeder's equation and Robertson's Secondary Theorem of Selection predicted qualitatively similar evolutionary responses to selection, and these theoretical predictions were largely consistent with our estimated genetic pattern. Overall, our study provides rare evidence for micro-evolution underlying (part of) an adaptive response to climate change in the wild, and illustrates how a combination of adaptive micro-evolution and phenotypic plasticity facilitated a shift towards earlier spring migration in this free-living population of common terns.

Microplastic ingestion by common terns (Sterna hirundo) and their prey during the non-breeding season

Current evidence demonstrates the presence and persistence of microplastics in the marine food web. Seabirds are predators in marine ecosystems and are highly exposed to marine plastic debris through the food. The aim of this work was to examine the presence of microplastics in a long-distance migratory seabird, the Common tern (Sterna hirundo) (n = 10), and in their prey (n = 53) during the non-breeding season. The study was conducted in Punta Rasa, Bahía Samborombón, province of Buenos Aires, which is an important resting and feeding location for migratory seabirds and shorebirds in South America. Microplastics were found in all the birds examined. The occurrence of microplastics in the gastrointestinal tract (GIT) of Common terns (n = 82) was higher than in regurgitated prey (RP) (n = 28), which is likely reflecting trophic transfer process. Almost all microplastics found were fibers and only 3 were fragments. Microplastics were sorted by color; transparent, black and blue-colored fibers were the most abundant plastic types. Characterization of the polymer type by Fourier Transform Infrared Spectrometry (FTIR) revealed that cellulose ester plastics, polyethylene terephtalate, polyacrylonitrile and polypropylene were the most abundant types found in both the gastrointestinal tract and prey. Our results highlight the high levels of ingested microplastics in Common terns and in their prey, and reflect a concern in this important location for migratory seabirds.

Mass mortality among colony-breeding seabirds in the German Wadden Sea in 2022 due to distinct genotypes of HPAIV H5N1 clade 2.3.4.4b.

Mass mortality was observed among colony-breeding seabirds in the German Wadden Sea area of the North Sea during the summer months of 2022. Several species' colonies were affected, most notably sandwich terns (Thalasseus sandvicensis), common terns (Sterna hirundo) and Germany's only northern gannet (Morus bassanus) colony on the island of Heligoland. Mortality in some tern colonies reached 40%, while other colonies were almost spared. In all cases, infections with the high-pathogenicity avian influenza virus (HPAIV) subtype H5N1 of clade 2.3.4.4b were identified to have caused the epidemic. Phylogenetic analysis of whole-genome sequences revealed that the outbreaks were dominated by two genotypes, Ger-10-21 N1.2 and Ger-10-21 N1.5, previously identified in Germany. Spatiotemporal analyses of phylogenetic data suggested that these viruses could have entered the continental North Sea coastal region via the British Isles. A close linkage of viruses from tern colonies in the German Wadden Sea was evident with further connections to breeding colonies in Belgium and the Netherlands, and further spread to Denmark and Poland. Several of the affected species are endangered, such that negative effects of epizootic HPAIV infections on populations are feared, with uncertain long-term consequences.

Importance of shallow river topography for inland breeding Common Terns

Importance of shallow river topography for inland breeding Common Terns

Surveillance of avian malaria and related haemoparasites in common terns (Sterna hirundo) on the Atlantic coast of South America.

Haemosporidia (Apicomplexa, Haemosporida) are protozoa that infect vertebrate blood cells and are transmitted by vectors. Among vertebrates, birds possess the greatest diversity of haemosporidia, historically placed in 3 genera: Haemoproteus, Leucocytozoon and Plasmodium, the causative agent of avian malaria. In South America, existing data on haemosporidia are spatially and temporally dispersed, so increased surveillance is needed to improve the determination and diagnosis of these parasites. During the non-breeding season in 2020 and 2021, 60 common terns (Sterna hirundo) were captured and bled as part of ongoing research on the population health of migratory birds on the Argentinian Atlantic coast. Blood samples and blood smears were obtained. Fifty-eight samples were screened for Plasmodium, Haemoproteus and Leucocytozoon, as well as for Babesia parasites by nested polymerase chain reaction and by microscopic examination of smears. Two positive samples for Plasmodium were found. The cytochrome b lineages detected in the present study are found for the first time, and are close to Plasmodium lineages found in other bird orders. The low prevalence (3.6%) of haemoparasites found in this research was similar to those reported for previous studies on seabirds, including Charadriiformes. Our findings provide new information about the distribution and prevalence of haemosporidian parasites from charadriiforms in the southernmost part of South America, which remains understudied.

NESTING PECULIARITIES AND INTERLAY VARIABILITY OF THE STERNIDAE FAMILY BIRDS’ EGGS IN THE PRIPYAT RIVER MIDDLE STRECH FLOODPLAN

Purpose: to analyze the nesting features of birds of the Sternidae family living in the floodplain meadow of the Pripyat River. Methodology. For research, the route method was used, in which bird nests were identified during direct examination of the territory of the floodplain meadow. Hard-to-reach areas of the meadow were surveyed from a boat. To assess the morphological parameters of the eggs of birds of the Sternidae family, the eggs were measured using a caliper. The length (L) and diameter of the eggs (B) were measured. Based on the measurements, the index of intra-laying variability (iv) was determined. During the study period, 245 eggs of birds of the Sternidae family were measured, of which 88 eggs were in the Common tern, 60 eggs in the Little tern, 51 eggs in the White-winged tern and 46 eggs in the Whiskered tern. Scientific novelty. It has been established that the formation of multispecies colonies of birds of the Sternidae family makes it possible to qualitatively use territories favorable for nesting and provides protection of nests from raptors to accompanying bird species. The smallest intra-laying variability of the studied egg parameters was found in the common and barnacle tern, which is an indicator of the birds’ adaptability to nesting conditions. Conclusions. The nesting of White-winged black and Whiskered tern is directly dependent on floodwater level. A gradual decrease in the level of floodwaters leads to the drying up of the floodplain meadow and the impossibility of building nests, since these species build nests on aquatic plants or floating bogs. Nesting of Little and Common tern is limited by biotic factors, such as predation by Corvidae birds and other animals, as well as anthropogenic factors - people resting on the shore, fishermen and locals visiting the meadow, which in turn creates a disturbance factor for the birds. Among the bird species considered, the maximum value of the index of intra-variability of eggs laying in egg diameter (iv) was found for White-winged black tern (iv = 4.10 ± 0.52). The minimum value of this index is observed in Whiskered tern (iv = 3.41 ± 0.39). It should be noted that differences in this index among Common tern are less pronounced than among Marsh tern The maximum value of the index of intra-variability of eggs laying (iv) was found for Little Tern (iv = 5.42 ± 0.65). The minimum value of this indicator was found in Common tern (iv = 3.90 ± 0.44). For Marsh tern (Whiskered and White-winged black tern), the value of the index of intra-variability of eggs laying length (iv) does not differ significantly.

Nest‐site selection by cinnamon teal and other ground‐nesting ducks in Great Salt Lake wetlands

AbstractGround‐nesting ducks can reduce nest depredation by selecting nest sites where local physical structures or vegetation provide olfactory or visual concealment. We evaluated nest‐site selection by comparing duck nests to random sites during 2019 and 2020 in the impounded wetlands of Great Salt Lake (GSL), Utah, USA. During wet springs, most of the wetlands are underwater, leaving only the dams available as nesting substrate. We located the nests of 399 cinnamon teal (Spatula cyanoptera), 137 mallards (Anas platyrhynchos), and 162 gadwalls (Mareca strepera) on the dams. At nest and random sites, we measured overhead concealment, lateral concealment, average height of vegetation in the nest patch, standard deviation of vegetation height in the nest patch, tallest vegetation within 1 m of nest, dam width, and distance from the nest to the road along the center of the dam. We found that mallards and gadwalls did not select for any of these characteristics. Cinnamon teal selected for nest sites that had more overhead concealment. We also found mixed evidence that cinnamon teal selected nest sites where dams were wider. All species also favored heterogeneous patches of vegetation for nesting over homogenous ones. Duck nests had a clumped distribution in wetlands that contained colonies of American avocets (Recurvirostra americana), black‐necked stilts (Himantopus mexicanus), and common terns (Sterna hirundo), with nests located inside the colonies, but showed a random distribution in other wetlands. Prior to 1980, approximately half of the world's population of cinnamon teal nested in GSL wetlands, but since that time the nesting population has declined greatly. Given this decline, management actions should be conducted that will improve overhead cover and widen dikes within the species' nesting habitat.

Sex-specific changes in autosomal methylation rate in ageing common terns

Senescence, an age-related decline in survival and/or reproductive performance, occurs in species across the tree of life. Molecular mechanisms underlying this within-individual phenomenon are still largely unknown, but DNA methylation changes with age are among the candidates. Using a longitudinal approach, we investigated age-specific changes in autosomal methylation of common terns, relatively long-lived migratory seabirds known to show senescence. We collected blood at 1-, 3- and/or 4-year intervals, extracted DNA from the erythrocytes and estimated autosomal DNA methylation by mapping Reduced Representative Bisulfite Sequencing reads to a de novo assembled reference genome. We found autosomal methylation levels to decrease with age within females, but not males, and no evidence for selective (dis)appearance of birds of either sex in relation to their methylation level. Moreover, although we found positions in the genome to consistently vary in their methylation levels, individuals did not show such strong consistent variance. These results pave the way for studies at the level of genome features or specific positions, which should elucidate the functional consequences of the patterns observed, and how they translate to the ageing phenotype.

Distributing transmitters to maximize population-level representativeness in automated radio telemetry studies of animal movement

Telemetry is a powerful and indispensable tool for evaluating wildlife movement and distribution patterns, particularly in systems where opportunities for direct observation are limited. However, the effort and expense required to track individuals often results in small sample sizes, which can lead to biased results if the sample of tracked individuals does not fully capture spatial, temporal, and individual variability within the target population. To better understand the influence of sampling design on results of automated radio telemetry studies, we conducted a retrospective power analysis of very high frequency (VHF) radio telemetry data from the Motus Wildlife Tracking System for two species of birds along the United States Atlantic coast: a shorebird, the piping plover (Charadrius melodus), and a nearshore seabird, the common tern (Sterna hirundo). We found that ~ 100–150 tracked individuals were required to identify 90% of locations known to be used by the tracked population, with 40–50 additional individuals required to include 95% of used locations. For any number of individuals, the percentage of stations included in the sample was higher for common terns than for piping plovers when tags were deployed within a single site and year. Percentages of stations included increased for piping plovers when birds were tagged over multiple sites and, to a lesser extent, years, and increased with average length of the tracking period. The probability that any given receiver station used by the population would be included in a subsample increased with the number of birds tracked, station proximity to a migratory stopover or staging site, number of receiving antennas per station, and percentage of the tracked population present. Our results provide general guidance for the number and distribution of tagged birds required to obtain representative VHF telemetry data, while also highlighting the importance of accounting for station network configuration and species-specific differences in behavior when designing automated radio telemetry studies to address specific research questions. Our results have broad applications to remotely track movements of small-bodied migratory wildlife in inaccessible habitats, including predicting and monitoring effects of offshore wind energy development.

Variation in isotopic niche partitioning between adult roseate and common terns in the Northwest Atlantic

Co-occurring species with similar resource requirements often partition ecological niches at different spatial and temporal scales. In the Northwest Atlantic (NWA), federally endangered roseate terns Sterna dougallii nest almost exclusively in coastal island colonies alongside common terns S. hirundo. Roseate terns are prey specialists compared to common terns, which are opportunistic generalists; however, the 2 species forage on similar resources during the breeding season. The degree to which these species overlap in their adult foraging ecologies is not well understood. We compared the isotopic niches of nesting adult roseate and common terns by analyzing stable carbon (δ13C) and nitrogen (δ15N) isotopes in eggshell membrane tissues collected in 2018 and 2019 from 10 colonies that span their NWA breeding range. Our aim was to characterize interspecific patterns in δ13C and δ15N values, isotopic niche breadth, and isotope niche overlap. We additionally examined interannual and subregional differences between ‘cold-water’ colonies in the Gulf of Maine and ‘warm-water’ colonies in Southern New England and Long Island Sound. At the range-wide scale, there was a high degree of overlap in the overall isotopic niches of the 2 species; however, more variable patterns were observed at the colony scale, ranging from nearly complete overlap to complete separation. The isotopic niches of roseate terns were generally narrower than those of common terns, consistent with their respective specialist/generalist tendencies. While the influence of isotopic baselines limits our interpretation of interannual and subregional differences, isotopic niche breadths and overlap suggest consistency of relative foraging ecologies across these scales.

Managing conflict between nesting common terns and herring gulls

Context Due to the frequent depredation of eggs and chicks by herring gulls (Larus argentatus), numerous approaches to reduce their impact on tern colonies have been tested by wildlife managers. Previous studies have shown that the use of overhead lines presents a promising method to prevent gull nesting in tern colonies, but little work has evaluated if this approach is suitable for excluding both nesting and non-nesting gulls. Aims The goal of this study was to explore the efficacy of a preventative approach, overhead lines, versus a more widely practiced lethal approach, shooting and trapping. Specifically, we aimed to determine if methods differ in their abilities to deter both gull nesting and presence within treatment areas and identify impacts on common tern (Sterna hirundo) nesting within treatment areas. Methods We applied separate management strategies to two common tern colonies. In one colony, we removed herring gulls via shooting followed by trapping and nest removal, and in the other colony, we erected overhead lines with subsequent trapping at nests established in the treatment area. Key results Gulls appeared to adapt quickly to shooting efforts, limiting efficacy and resulting in no significant change in abundance from pre-treatment levels (P = 0.981). However, gull use of both the colony and surrounding brush declined significantly (P &lt; 0.001) following trapping and nest removal. Meanwhile, the number of gulls in the colony area declined from a pre-treatment average of 56 to only six, following the erection of overhead lines (P &lt; 0.001). Although six gull nests were established within the treatment area (overhead lines), they were not replaced once the parents were trapped and nests destroyed. Conclusions Tern nesting appeared to be unaffected by any of the implemented management activities. Our data suggest that overhead lines may present an alternative to lethal control when seeking to minimise the impacts of gulls on tern colonies. Implications The data presented in this manuscript can be used to guide managers in selecting actions to reduce conflict between gulls and breeding common terns. By using data-informed practices, managers can select the method best suited for their specific needs and priorities.

WATLAS: high-throughput and real-time tracking of many small birds in the Dutch Wadden Sea

Tracking animal movement is important for understanding how animals interact with their (changing) environment, and crucial for predicting and explaining how animals are affected by anthropogenic activities. The Wadden Sea is a UNESCO World Heritage Site and a region of global importance for millions of shorebirds. Due to climate change and anthropogenic activity, understanding and predicting movement and space-use in areas like the Wadden Sea is increasingly important. Monitoring and predicting animal movement, however, requires high-resolution tracking of many individuals. While high-resolution tracking has been made possible through GPS, trade-offs between tag weight and battery life limit its use to larger species. Here, we introduce WATLAS (the Wadden Sea deployment of the ATLAS tracking system) capable of monitoring the movements of hundreds of (small) birds simultaneously in the Dutch Wadden Sea. WATLAS employs an array of receiver stations that can detect and localize small, low-cost tags at fine spatial (metres) and temporal resolution (seconds). From 2017 to 2021, we tracked red knots, sanderlings, bar-tailed godwits, and common terns. We use parts of these data to give four use-cases revealing its performance and demonstrating how WATLAS can be used to study numerous aspects of animal behaviour, such as, space-use (both intra- and inter-specific), among-individual variation, and social networks across levels of organization: from individuals, to species, to populations, and even communities. After describing the WATLAS system, we first illustrate space-use of red knots across the study area and how the tidal environment affects their movement. Secondly, we show large among-individual differences in distances travelled per day, and thirdly illustrate how high-throughput WATLAS data allows calculating a proximity-based social network. Finally, we demonstrate that using WATLAS to monitor multiple species can reveal differential space use. For example, despite sanderlings and red knots roosting together, they foraged in different areas of the mudflats. The high-resolution tracking data collected by WATLAS offers many possibilities for research into the drivers of bird movement in the Wadden Sea. WATLAS could provide a tool for impact assessment, and thus aid nature conservation and management of the globally important Wadden Sea ecosystem.

Shorebird community and diversity in Bagan Serdang Beach, North Sumatra

The occurrence of shorebirds is strongly influenced by environmental factors, especially food availability. Shorebirds are closely linked to their habitat conditions, so they seek out feeding sites according to their life cycle. Coastal conditions that have changed due to human activities may affect the assemblage of shorebird community. The aim of this study is to determine the diversity of shorebird species and the factors that influence them. Bird observations were made for three days using the point count method while the number of individuals was estimated by using “block method”. The results revealed 17 shorebird species from the families, Charadriidae, Scolopacidae and Sternidae. The dominant species were Charadrius mongolus, Pluvialis fulva and Sterna hirundo. The number of species in the morning observations was higher than in the afternoon. The diversity index for migratory birds ranges from 1.16 to 1.96, which is relatively low. This study showed that mudflats in Bagan Serdang Beach, Pantai Labu District is occupied by shorebirds in this region.

BIRD COMPOSITION IN FOREST AND COASTAL ZONE OF PULAU TINGGI, JOHOR, MALAYSIA

Documentation of bird composition on the islands around Peninsular Malaysia is scarce and the attention is mainly focused on Malaysia’s Borneo Islands. Therefore, this study aims to fulfil this knowledge gap by documenting the bird composition in Pulau Tinggi. The study was conducted from March to August 2019 using mist-netting and direct observation methods. A total of 39 bird species belonging to 24 families were recorded. Among these, 28 species were residents, four species were residents migrants and seven were migrants. Migrant species include Wood sandpipers (Tringa glareola), Common Sandpipers (Actitis hypoleucos), Malay Hawk-cuckoo (Hierococcyx fugax), Arctic- Warbler (Phylloscopus borealis), Brown Shrike (Lanius cristatus), Siberian Blue Robin (Luscinia cyane) and Common Tern (Sterna hirundo). Regarding conservation status, only one species was listed as Near Threatened: The White-chested Babbler (Trichastoma rostratum). Our result shows that the coastal area is more diverse (H=2.252) than the forest area (H=1.933). However, birds in the forest area were more evenly distributed with an evenness index score (forest = 0.5759) over (coastal=0.3806). Thus, we conclude that despite its small size, Pulau Tinggi accommodates a variety of bird species, where the conservation action plan for the continued survival of birds on this island needs to be implemented.

Abnormal Plumage in Adult Common Terns Sterna hirundo during the Breeding Season

Some bird species change their plumage colour on a seasonal basis, mostly between cryptic non-breeding plumage and conspicuous breeding plumage. Adult Common Terns Sterna hirundo moult their body feathers twice each year, resulting in two types of plumages, those typical to breeding and non-breeding seasons, which exhibit minor differences in the colours of some feathers, as well as the bare parts. Here, we report evidence of an abnormal plumage in adult Common Terns (sometimes referred to as ‘portlandica’), with two individuals exhibiting non-breeding like plumage during the breeding season. These terns were documented in a breeding colony in Northern Israel. This report could lead to future research into the causes and consequences of plumage maturation avoidance in adult birds.

Diversity of fauna species in the mangrove ecosystem of Youtefa Bay Tourism Park, Papua, Indonesia

Abstract. Sari A, Tuwo A, Saru A, Rani C. 2022. Diversity of fauna species in the mangrove ecosystem of Youtefa Bay Tourism Park, Papua, Indonesia. Biodiversitas 23: 4490-4500. Youtefa Bay Tourism Park is a mangrove ecosystem in Jayapura City, Papua, Indonesia with high importance for biodiversity conservation as well as providing livelihood for local communities. Yet, information regarding the biological diversity of the mangrove ecosystem is lacking. This information is important to assess the state of the mangrove and to support its sustainable management of this area. This research aimed to determine the faunistic diversity of Youtefa Bay Tourism Park. The research was conducted from August 2019 to February 2020 using line transect method with quadrant to record species and the number of individuals. The results showed that in the studied area there were six, five and 27 species of birds, reptiles and macrozoobenthos, respectively. The density of birds ranged from 2.35-23.94 ind/ha with Sterna hirundo of the Sternidae family having the highest density. The reptile species density ranged between 20 and 66.67 ind/ha, while the most common macrozoobenthos species were from Gastropoda and Pelecypoda classes. The highest and lowest relative abundance for birds were S. hirundo and Sula lencogastes with 20% and 5%, while that of reptiles were Mabouya sp. and Varanus salvadorii with 37% and 15%, and for macrozoobenthos species were Duplicaria duplicata and Solen sp. with 9.93% and 0.35%, respectively. The Diversity Index (H’) of birds, reptiles, and macrozoobenthos ranged of 0.29-1.39, 0.27-1.61, and 2.92-3.04, respectively. The diversity index was as low at Abepantai and Youtefa Bay Pier, while moderate at Tobati, Enggros, and Nafri Villages. Water quality parameters indicated that the waters in Youtefa Bay Tourism Park were still suitable for the survival of biota and the preservation of the mangrove ecosystem. The results of this study might be useful for monitoring the status of the mangrove ecosystem in the future and for baseline information in developing sustainable management of Youtefa Bay Tourism Park.