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1.
We isolated 45 new Kentish plover (Charadrius alexandrinus) microsatellite loci. These were tested for polymorphism in 42 Kentish plovers breeding in the Çukurova Delta, Turkey. Thirty‐six of the 45 loci were polymorphic with observed heterozygosity varying between 0.22 and 0.93. Genotypes of individuals of known sex indicated that two loci were sex‐linked (Calex‐26 is located on the Z chromosome and Calex‐31 on the W chromosome). Additionally, we tested all loci for amplification in four other species of Charadridae (Kittlitz's plover, Madagascar plover, three‐banded plover and white‐fronted plover). On average 34 loci amplified per species (range 29–36).  相似文献   

2.
Adults of Maritrema obstipum (Digenea: Microphallidae) were found in the intestines of 4 species of migratory birds, including the sanderling (Crocethia alba), Kentish plover (Charadrius alexandrines), Mongolian plover (Charadrius mongolus), and red-necked stint (Calidris ruficollis), collected from Yubu Island, Chungcheongnam-do, Korea. The worms of were 451 × 265 μm in size, and were easily identifiable as Maritrema species by the presence of the cirrus sac, and the ring-like distribution of the vitellaria. More specifically, the ejaculatory duct curved posteromedially, and the 2 parts of vitelline follicles were found to be distinct at the posterior end. The eggs were brown-colored, and 19.8 × 12.3 μm in size. All these findings implicated M. obstipum as the pertinent species of the worms. Beside these, adult worms of Gynaecotyla squatarolae, Parvatrema duboisi, and Acanthoparyphium sp. were also discovered. This is the first report establishing migratory birds as the natural definitive hosts for M. obstipum.  相似文献   

3.
Role of intestinal goblet cells (GCs) in the expulsion of Gymnophalloides seoi was studied using 4 strains of mice, ICR, C3H/ HeN, BALB/c, and C57BL/6, after infection with 200 metacercariae isolated from oysters. On day 7 postinfection (PI), significantly higher (P < 0.05) worm recovery rates (WRRs) were observed in ICR (29.5 +/- 12.0%) and C3H/HeN (14.8 +/- 8.2%) than in BALB/c (5.7 +/- 5.3%) and C57BL/6 (0.8 +/- 1.1%) mice. Alteration of the GC mucins was marked in C57BL/6 mice. On day 14 PI, 5.2 +/- 5.2% and 0.6 +/- 0.7% of worms were recovered only from ICR and C3H/HeN mice. When C57BL/6 mice were immunosuppressed with prednisolone, WRR on day 7 PI increased to 11.7 +/- 13.9%, whereas the GC hyperplasia and mucin alteration diminished significantly. The results suggest that expulsion of G. seoi from the intestine is dependent on immune responses of the host, and GCs may be an important effector.  相似文献   

4.
One of the expected effects of the global warming is changing coastal habitats by accelerating the rate of sea level rise. Coastal habitats support large number of marine and wetland species including shorebirds (plovers, sandpipers and allies). In this study, we investigate how coastal habitats may be impacted by sea level rise in the Farasan Islands, Kingdom of Saudi Arabia. We use Kentish plover Charadrius alexandrinus – a common coastal breeding shorebird – as an ecological model species to predict the influence of sea level rise. We found that any rise of sea level is likely to inundate 11% of Kentish plover nests. In addition, 5% of the coastal areas of Farasan Islands, which support 26% of Kentish plover nests, will be flooded, if sea level rises by one metre. Our results are constrained by the availability of data on both elevation and bird populations. Therefore, we recommend follow-up studies to model the impacts of sea level rise using different elevation scenarios, and the establishment of a monitoring programme for breeding shorebirds and seabirds in Farasan Islands to assess the impact of climate change on their populations.  相似文献   

5.
Studies on Gymnophalloides seoi (Digenea: Gymnophallidae) and human infections are briefly reviewed. This minute intestinal fluke was first discovered from a Korean woman suffering from acute pancreatitis and gastrointestinal troubles. It was described as a new species by Lee, Chai and Hong in 1993. The southwestern coastal village where the patient resided was found to be a highly endemic area, and additional endemic areas have been identified. The parasite is very small, 0.33-0.50 mm long and 0.23-0.33 mm wide, and characterized by the presence of a ventral pit. The first intermediate host remains unknown, but the second intermediate host has been found to be the oyster Crassostrea gigas. Man and the Palearctic oystercatcher Haematopus ostralegus have been shown to be natural definitive hosts, and wading birds including the Kentish plover Charadrius alexandrinus are highly susceptible to experimental infection. Gerbils, hamsters, cats, and several strains of mice were also susceptible laboratory hosts. In experimentally infected mice, the parasites inhabit the small intestine, pinching and sucking the root of villi with their large oral suckers, but they did not invade beyond the mucosa in immunocompetent mice. However, they were found to invade the submucosa in immunosuppressed mice. Human G. seoi infections have been found in at least 25 localities; 23 islands on the Yellow Sea or the South Sea, and 2 western coastal villages. The highest prevalence was found in a village on Aphaedo, Shinan-gun (49% egg positive rate); other areas showed 0.8-25.3% prevalence. Infected people complained of variable degrees of gastrointestinal troubles and indigestion. The infection can be diagnosed by recovery of eggs in the feces; however, an expert is needed to identify the eggs. Praziquantel, 10 mg/kg in single dose, is effective for treatment of human infections. Eating raw oysters in endemic areas should be avoided.  相似文献   

6.
The loss and degradation of natural habitats in coastal areas worldwide has adversely affected many waterbird species, changing their breeding distribution and reducing their productivity. Anthropogenic habitats such as saltpans can provide alternative or complementary habitats for waterbirds and mitigate the increasing human impact on natural coastal habitats. Unvegetated linear paths between salt ponds are used by ground‐nesting waterbird species to breed but their linear structure may facilitate the detection of nests by predators. This negative effect may, however, be counterbalanced by the advantages of breeding in mixed colonies. To evaluate the importance and the risks of breeding in saltpans we used the Kentish plover Charadrius alexandrinus breeding in coastal saltpans of southern Portugal as a model species. Specifically, we assessed the role of nest‐site characteristics, predation and nesting proximity to species with aggressive antipredator behaviour (black‐winged stilt Himantopus himantopus) on their breeding success. Kentish plovers selected nest‐sites on the edges of paths, with about 20% of water around the nest, and a mean visibility of more than 72%; however nest‐site characteristics were not correlated with nesting success. Predation was the main cause of nest loss in saltpans (42%); carrion crows Corvus corone were responsible for most daylight nest predation (58%) and red fox (Vulpes vulpes; 73%) for night predation. An 8‐yr monitoring plan of a Kentish plover population showed a linear increase in their breeding success as their breeding season increasingly overlapped with that of the black‐winged stilt. An experiment with artificial nests showed a significant increase in the number of exposure days (7 to 12) when these nests were within close distance of black‐winged stilt nests. Overall, our results showed that saltpans are an important alternative breeding habitat for the Kentish plover, especially for the maintenance of mixed species colonies.  相似文献   

7.
The growth and development of Gymnophalloides seoi were studied in C3H/HeN mice and effects of immunosuppression of the host on the worm development were observed. Two hundred metacercariae of G. seoi were orally administered to each mouse, and worms were recovered on days 1, 3, 5, 7, 14 and 21 post-infection (PI). The worm recovery rate was significantly higher in immunosuppressed (ImSP) mice than in immunocompetent (ImCT) mice except on days 1 and 3 PI. The worms attained sexual maturity by day 3 PI with eggs in the uterus, and worm dimensions and the number of uterine eggs continuously increased until day 14 PI in ImSP mice. Worms recovered from ImSP mice were significantly larger in size than those from ImCT mice on days 1 and 3 PI, and the number of uterine eggs was significantly larger in ImSP mice on days 5 and 7 PI. Genital organs such as the ovary, testes, and vitellaria, that were already developed in the metacercarial stage, grew a little in size until day 14 PI. The results show that the C3H/HeN mouse is, though not excellent, a suitable laboratory host for G. seoi.  相似文献   

8.
In the past 60 years, reservoirs have reshaped riverine ecosystems and transformed breeding habitats used by the threatened piping plover (Charadrius melodus; hereafter plover). Currently, 29 % of the Northern Great Plains plover population nests at reservoirs that might function as ecological traps because reservoirs have more diverse habitat features and greater dynamics in water levels than habitats historically used by breeding plovers. We examined factors influencing daily survival rates (DSR) of 346 plover nests at Lake Sakakawea (SAK; reservoir) during 2006–2009 by evaluating multiple a priori models, and we used our best model to hindcast nest success of plovers during 1985–2009. Our observed and hindcast estimates of nest success were low compared to published estimates. Previous findings indicate that plovers prefer nest sites that are low relative to water level. We found that elevation of nests above the water level had a strong positive correlation with DSR because water levels of SAK typically increased throughout the nesting period. Habitat characteristics on the reservoir differ from those that shaped nest-site selection for plovers. Accordingly, extraordinary nest loss occurs there in many years, largely due to inundation of nests, and based on low fledging rates those losses were not compensated by potential changes in chick survival. Therefore, our example supports the concept of ecological traps in birds because it addresses quantitative assessments of habitat preference and productivity over 25 years (since species listing) and affects a large portion of the population.  相似文献   

9.
We describe an unknown mode of solar‐assisted egg development in the crab plover Dromas ardeola, a shorebird that breeds in self‐excavated burrows. The insulating properties of the nest burrow and the intense solar radiation allowed egg development at near‐optimal temperature (35.2°C±0.2) and humidity (60.2%±4.4), allowing a very low incubation attendance by the parent birds (28.3% of time, with recesses lasting up to 58 h). Crab plovers did not abandon completely parental incubation, possibly because of the need to turn their egg, and because the slight warming provided by parents (0.8°C) may improve hatching. This is the first case of solar assisted incubation in a species unrelated to the Megapodiidae, the only birds known to develop their eggs without contact incubation.  相似文献   

10.
1. One of the fundamental insights of behavioural ecology is that resources influence breeding systems. For instance, when food resources are plenty, one parent is able to care for the young on its own, so that the other parent can desert and became polygamous. We investigated this hypothesis in the context of classical polyandry when females may have several mates within a single breeding season, and parental duties are carried out largely by the male. 2. We studied a precocial wader, the Kentish plover Charadrius alexandrinus, that exhibits variable brood care such that the chicks may be raised by both parents, only by the female or, more often, only by the male. The timing of female desertion varies: some females desert their brood at hatching of the eggs and lay a clutch for a new mate, whereas other females stay with their brood until the chicks fledge. Kentish plovers are excellent organisms with which to study breeding system evolution, as some of their close relatives exhibit classical polyandry (Eurasian dotterel Eudromias morinellus, mountain plover Charadrius montanus), whereas others are polygynous (northern lapwing Vanellus vanellus). 3. Kentish plovers raised their broods in two habitats in our study site in southern Turkey: saltmarsh and lakeshore. Food intake was higher on the lakeshore than in the saltmarsh as judged from feeding behaviour of chicks and adults. As the season proceeded and the saltmarsh dried out, the broods moved toward the lakeshore. 4. As the density of plovers increased on lakeshore, the parents spent more time defending their young, and female parents stayed with their brood longer on the lakeshore. 5. We conclude that the influence of food abundance on breeding systems is more complex than currently anticipated. Abundant food resources appear to have profound implications on spatial distribution of broods, and the social interactions between broods constrain female desertion and polyandry.  相似文献   

11.
ABSTRACT Mountain Plovers (Charadrius montanus) are grassland birds that often breed in close association with colonies of black‐tailed prairie dogs (Cynomys ludovicianus). However, not all colonies provide plover nesting habitat or habitat of equal quality, and the characteristics of colonies important for plovers remain poorly understood. Over two years, I used plover distribution surveys, territory mapping, and habitat sampling to study habitat use by plovers in prairie dog colonies in shortgrass prairie in northeastern New Mexico. My objective was to document important components of plover breeding habitat in colonies by comparing characteristics of used and unused habitats at three spatial scales: colony, territory, and nest‐site. I found evidence of plover breeding in 14 of 44 colonies in 2009 and 13 of 43 colonies in 2010. Based on logistic regression, the probability of a colony being occupied by plovers was positively associated with colony size, but negatively associated with mean vegetation height. Preference for larger colonies could relate to minimum habitat requirements, or a potential tendency of this species to nest in social clusters. Shorter vegetation height was strongly correlated with greater bare ground and lower forb/subshrub cover, all characteristics that may be related to plover predator avoidance and foraging microhabitat. At both the territory and nest‐site scale, areas used by plovers had shorter vegetation, more bare ground, and less forb/subshrub cover than unused areas. Nest sites were also more sloped, perhaps to reduce risk of flooding, and located further away from the nearest prairie dog burrow, perhaps to reduce risk of disturbance. Overall, my results show that plover use of prairie dog colonies was influenced by landscape and habitat features of colonies, and suggest that large colonies are particularly valuable because they are most likely to contain adequate areas with preferred habitat characteristics.  相似文献   

12.
In order to verify the role of migrating birds as natural definitive hosts for Gymnophalloides seoi (Gymnophallidae), Palearctic oystercatchers, Haematopus ostralegus, were caught from several western coastal areas in the Republic of Korea and examined for intestinal flukes. Five (71.4%) of 7 oystercatchers were infected with 302-1,660 (mean 892) adult G. seoi. In intestinal sections of the host, worms were found in the intervillous space of the mucosal layer. We conclude that the oystercatcher is a natural definitive host for G. seoi.  相似文献   

13.
Today's intensive farming practices are known to have affected farmland biodiversity negatively in many different ways. As far as birds are concerned, they are known to have suffered during both summer and winter. Relatively little is known about the effects on birds during migration. We studied the stopover ecology of the Eurasian golden plover Pluvialis apricaria, a species listed in EU Birds Directive, in intensively farmed arable land in southernmost Sweden in the autumns of 2003–2007. We used key ecological variables (length of stay, fat deposition and moult) as fitness proxies to evaluate how the birds manage in this habitat. Eurasian golden plovers were present in large numbers mainly on arable fields from early August to November and radio‐tagged birds were found to stay in the area for up to three months. Adult birds carried out a substantial part of their flight feather moult during their stay. Body mass increased only somewhat during moult, but from the last stages of moult and onwards fuel loads corresponding to 24% above lean body mass (LBM) were accumulated at a rate of 0.5% of LBM per day, before the birds departed. Juveniles arrived later, from mid Sep., and had a similar pattern of fuel deposition. The fact that the birds choose to stay for long periods, moult in the area, and manage to store substantial fuel loads strongly suggests that Eurasian golden plovers do well in this intensively farmed arable land.  相似文献   

14.
Much of the breeding range for the mountain plover (Charadrius montanus) occurs in shortgrass steppe and mixed-grass prairie in the western Great Plains of North America. Studies of mountain plovers in shortgrass steppe during the 1970s and 1990s were focused in Weld County, Colorado, which was considered a key breeding area for the species. These studies, however, did not include habitats influenced by black-tailed prairie dogs (Cynomys ludovicianus) or prescribed fire. The role of these 2 rangeland disturbance processes has increased substantially over the past 15 years. During 2008–2009, I used radial distance point count surveys to estimate mountain plover densities early in the nesting season in 4 habitats on public lands in Weld County, Colorado. All 4 habitats were grazed by cattle during the growing season at moderate stocking rates but had different additional disturbances consisting of 1) dormant-season prescribed burns, 2) active black-tailed prairie dog colonies, 3) black-tailed prairie dog colonies affected by epizootic plague in the past 1–2 years, and 4) rangeland with no recent history of fire or prairie dogs. Mountain plover densities were similar on active black-tailed prairie dog colonies ( = 6.8 birds/km2, 95% CI = 4.3–10.6) and prescribed burns ( = 5.6 birds/km2, 95% CI = 3.5–9.1). In contrast, no plovers were detected at randomly selected rangeland sites grazed by cattle but lacking recent disturbance by prairie dogs or fire, even though survey effort was highest for this rangeland habitat. Mountain plover densities were intermediate (2.0 birds/km2, 95% CI = 0.8–5.0) on sites where black-tailed prairie dogs had recently been extirpated by plague. These findings suggest that prescribed burns and active black-tailed prairie dog colonies may enhance breeding habitat for mountain plovers in shortgrass steppe and illustrate the potential for suppressed or altered disturbance processes to influence habitat availability for declining wildlife species. © 2011 The Wildlife Society.  相似文献   

15.
ABSTRACT We calculated expenditures and hours of staff and volunteer time dedicated to monitoring and managing the United States breeding population of Atlantic Coast piping plovers (Charadrius melodus) in 1993 and 2002 and considered implications for recovery of this management-dependent species. In 2002, 73 federal, state, and local governmental agencies and private organizations played key roles in conservation efforts at 281 piping plover breeding sites. Total inflation-adjusted estimated expenditures increased by 51% between 1993 and 2002, from US$2.28 million to $3.44 million, but annual per-pair expenditures declined 4% from $2,459 to $2,350, and hours of paid-staff effort were similar (93 hr/pair in 1993, 95 hr in 2002). Expenditures for on-site monitoring and management were greater than for 6 other categories of expenses in both years and increased from 42% to 59% of total costs between 1993 and 2002. Staff time and expenditures were higher at sites where more labor-intensive efforts to protect plovers from recreation and other human use were necessitated by greater human accessibility. Total expenditures in 2002 were modest compared to those for some other threatened and endangered species and to costs of large beach-stabilization projects. Our results provide a baseline for estimating future costs of piping plover protection, including development and implementation of the long-term management agreements that will be required to remove this species from United States Endangered Species Act protection. Impediments to reducing costs for Atlantic Coast piping plovers are the species’ widespread distribution at low densities and the unrelenting threats posed by human activities and predators. Modest economies of scale may be achieved through arrangements for management and monitoring that span multiple landowners and include other at-risk beach species.  相似文献   

16.
During nesting, many temperate and tropical shorebirds are exposed to direct solar radiation and face heat stress. The aim of our study was to determine whether belly-soaking (wetting of ventral plumage) contributes to reducing excess body heat in Kentish plovers Charadrius alexandrinus. We captured incubating plovers on sunny days at their exposed nests, and placed them inside cloth bags at ground level in exposed sites for 5 min. This produced an increase in the ambient temperature experienced by the plovers, as well as an increase in the body temperature of the plovers. We simulated belly-soaking by submerging the ventral parts in water for about 10 s immediately after removing the birds from the bag. The body temperature of the plovers was lowered after simulated belly-soaking. Our results indicate that belly-soaking is a behavioural strategy to quickly reduce body temperature in heat-stressed plovers.  相似文献   

17.
The immune response of inbred strains of mice was studied following infection with isolates of Trichinella from a pig (P1), an arctic fox (AF1), and T. spiralis var. pseudospiralis (TP). Strains of mice previously characterized as highly resistant to a separate pig isolate of T. spiralis responded to the P1 and AF1 isolates by expelling over 80% of the worms by day 10 postinfection (PI), and by suppressing the in vitro release of newborn larvae by female worms. However, the response induced by AF1 worms was expressed more quickly when compared to responses induced by the P1 and TP isolates. The host response to TP was less as recovery was always higher at day 10 PI and antifecundity effects were not induced in TP worms even in highly resistant strains of mice. Strains of mice previously characterized as susceptible to T. spiralis infection were slow to develop resistance when compared to the resistant mouse strains, but even among the susceptible strains, infection with AF1 induced a more rapid response. The mouse strains used in these experiments allowed us to assess the role of the major histocompatibility complex (MHC) and/or non-MHC genes in influencing the responses observed. As previously reported for a pig isolate of T. spiralis, both MHC and non-MHC genes influenced the rate at which worms were expelled from the gut and the host response that limits the fecundity of adult female worms.  相似文献   

18.
Restoring historical disturbance regimes to enhance habitat for grassland birds can conflict with livestock production goals and has been controversial because of uncertainty in the frequency and pattern of different disturbances prior to European settlement. We studied nesting habitat for the mountain plover (Charadrius montanus) in relation to prescribed fire, grazing by large herbivores (cattle), and grazing by black-tailed prairie dogs (Cynomys ludovicianus) in the shortgrass steppe of northeastern Colorado. Breeding mountain plovers primarily occurred on black-tailed prairie dog colonies or areas burned during the previous dormant season. Vegetation surrounding mountain plover nests and foraging locations was characterized by a fine-scale mosaic of prostrate (<4 cm tall) vegetated patches interspersed with >35% bare soil in a given square meter, with this fine-scale pattern distributed over a broad (>100-m radius) area. Mountain plovers rarely occupied grassland lacking prairie dogs or recent fire, but those that did selected sites with similar vegetation height and bare soil exposure as sites on burns and prairie dog colonies. Vegetation structure at mountain plover-occupied sites was also similar to random sites on burns and prairie dog colonies, but differed substantially from sites managed only with cattle. Intensive cattle grazing at twice the recommended stocking rate during spring (Mar–May) or summer (May–Oct) for 6 years produced significantly less bare soil than burns and prairie dog colonies, particularly following years with average or above-average precipitation. Thus, intensive cattle grazing did not substitute for prairie dog grazing or fire in terms of effects on vegetation structure and mountain plover habitat. Both prescribed burning and increased size and distribution of black-tailed prairie dog colonies appear to be effective and complementary means to manage for mountain plover breeding habitat in shortgrass steppe. Provision of mountain plover habitat has tradeoffs with traditional management for livestock production. Thus, managers need to clearly define desired outcomes for management to provide multiple ecosystem goods and services. © 2012 The Wildlife Society.  相似文献   

19.
Many animals have multiple sexual ornaments, a fact variously explained as signalling of multiple attributes, or nonadaptive retention of now redundant, but previously informative, signals. Despite the widespread occurrence of multiple ornaments, and the theoretical interest in how they are maintained by selection, there have been few experimental studies of the phenomenon. We investigated the role of two ornaments, each plausibly signalling different male attributes, in attracting a new mate in the Kentish plover, Charadrius alexandrinus. Previously we have shown that male Kentish plovers vary in how long they take to acquire a new mate, and we hypothesized that this variation may relate to their attractiveness or parental ability. We created single males by removing their mate and clutch, and then manipulated both their badge size (a presumed signal of either their genetic quality or their dominance status and hence defensive abilities) and the length of their flank feathers (a presumed signal of their parental quality in incubation) in a 2×2 factorial design. We found no difference in remating times between manipulated and control males. Furthermore, neither body size nor body condition of males was related to their remating times, although males with enlarged badges spent less time fighting than control males. Taken together, our results suggest that female Kentish plovers do not use either badge size or the length of flank feathers as cues in their mate choice decisions. However, badge size may influence male-male competition.  相似文献   

20.
Conservation of shorebirds throughout their breeding and migratory ranges has become a priority as shorebird populations decline globally. Along the North Atlantic Coast, management efforts have particularly focused on preserving nesting habitat for piping plovers (Charadrius melodus), which are protected under the Endangered Species Act. It is unclear whether these conservation measures suffice to protect foraging habitat for piping plovers and other shorebirds on stopover during migration along the Atlantic Flyway. To evaluate the extent to which conservation of piping plover nesting areas extends to all habitats used by plovers, and to determine whether these protections also benefited non-breeding migratory shorebirds in the region, we conducted weekly shorebird surveys, recording the number and locations of piping plovers and other species, during northward and southward migration on Fire Island and Westhampton Island, New York, USA, from 2014–2016. We used canonical correspondence analysis (CCA) to assess the degree of spatiotemporal overlap between breeding plovers, foraging plovers, and other migratory shorebirds that temporarily stage at the site. The spatiotemporal distribution of migratory shorebirds matched more closely with piping plovers seen during foraging than piping plovers observed tending nests and engaging in other breeding activities. Migratory shorebirds and foraging piping plovers were more abundant and frequent in wet intertidal zones outside of fenced-off nesting areas, which were not protected under current management regimes. Therefore, additional protection of piping plover foraging habitat could benefit plovers and migratory shorebirds that use similar feeding grounds during stopover on northward and southward migration. © 2020 The Wildlife Society.  相似文献   

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