Intraspecific Nest Parasitism Research Articles

Deep Learning-Based Parasitic Egg Identification From a Slender-Billed Gull’s Nest

Intraspecific nest parasitism is a phenomenon that attracts the attention of biologists since it helps in saving the endangered species such as Slender Billed Gull. The problem comes from the fact that a parasite female lays its eggs in the nest of another female (host) of the same species which causes the abandon of the nest by the host. This behavior causes a significant reduction in future birds number and leads to the expansion of this specie. Thus, there has been an urgent necessity to clean the nest from parasitic eggs. So, our aim is to built an automatic parasitic egg identification system based on egg visual features information. Our system uses deep learning models which have proven their success for image classification. Indeed, our system conduct an egg image’s pre-processing phase followed by Fast Beta Wavelet Network (FBWN) to extract the most efficient descriptors (shape, texture, and color). Then, these features will be inputted to the Stacked AutoEncoder for egg classification. Our proposed system, has been evaluated on 91-egg dataset collected from 31 clutches of eggs in Sfax region, Tunisia. Our model has given a parasitic egg identification accuracy of 89.9% which has outperformed the state of the art method and shows the efficiency and the robustness of our system.

Instances of intraspecific nest parasitism in eastern and Rio Grande wild turkeys

AbstractNest parasitism can play an important role in processes regulating population dynamics of both hosts and parasites. Inter‐ and intra‐specific nest parasitism are 2 alternative reproductive strategies observed to occur in about 1% of all bird species. Recently, low productivity in wild turkey (Meleagris gallopavo) populations has resulted in population declines across the southeastern United States. Reproductive output may be influenced by nest parasitism, but the extent of nest parasitism and how it may be related to productivity of wild turkey populations are poorly understood. Herein, we illustrate 6 unreported examples of intraspecific nest parasitism obtained using GPS telemetry data from female wild turkeys in Georgia and Louisiana during 2014−2018. Further, we report 3 occurrences of nest parasitism in Texas using photographic evidence. Our findings suggest that ≥6% of nests are potentially parasitized, and that multiple females may visit and parasitize a single nest. Given recent declines in reproductive output of wild turkeys throughout the southeastern United States, we encourage researchers to continue assessing potential for nest parasitism across wild turkey populations and how this potential may be influenced by predator abundance and activity.

The morphometric analysis of Eurasian coot eggs (Fulica atra) under the local conditions from Câmpenești, North-Western Romania

The aim of the present paper was to analyze the measurements of the Eurasian Coot (Fulica atra) eggs in order to evaluate if the local conditions, presented here, differ in some way from older data found in references dating to 1955 in Romania. The data were collected from the Eurasian Coot nests identified (N=8) at Câmpenești fishponds, located in North-Western Romania, in May 2018. The clutch size was 7.5 ±1.6, ranging from 5 to 10 eggs. The mean egg length was 50.81 mm, and the mean egg breadth was 34.5 mm with higher variability in case of the first measurement. The mean egg volume was 31.3 cm3 which is much smaller than reported in the Romanian references (36.13 cm3). Regarding intra-clutch variance, we found that some clutches manifest a higher length, breadth and volume variance than others which can be a result of the intraspecific nest parasitism or environmental variances. The results brought some extensions of egg length and egg breadth limits and also may reflect a decrease in egg size over time.

Nesting Biology of the Scaly-Sided Merganser (Mergus squamatus, Mergini, Anatidae) in Primorye, Russia

The nesting biology of the scaly-sided merganser (Mergus squamatus) was investigated over 17 years (2001–2017) in both artificial and natural nest sites in Primorye. Artificial nest sites were provided along fifteen rivers. A total of 205 nests were recorded: 190 nests in artificial sites and 15 in natural cavities. The occupation rate of nest boxes (27.8%) was significantly higher than that of nest tubes (20.2%). The clutch size averaged 11.08 ± 0.05 (N = 145) eggs. Inter- and intraspecific nest parasitism was described, and the effect of parasitism on nest success was evaluated. Clutch onset (average in terms, i.e., median clutch) during the study period was revealed to be more advanced compared with the initial years. Apparent nest success (70.4 ± 4.0%) was independent of the cavity type, with no significant difference noted between artificial and natural sites. The artificial nest program is an effective way to increase the productivity of this endangered bird species. A total of 1334 ducklings reliably hatched in artificial nest sites during 2002–2017.

New species on the list of species with intraspecific nest parasitism

Abstract Intraspecific nest parasitism has only recently received more attention from ornithologists. In 2001, Yom-Tov published a list of 234 species that had exhibited this behaviour. I have since found literature data on four additional species in which intraspecific nest parasitism has been observed. No such record has so far been published from Hungary. This study presents records on 25 species from Hungary and on one species from Croatia, out of which I have not found any reference for intraspecific nest parasitism in the literature for Cattle Egret (Bubulcus ibis), Eurasian Thick-knee (Burhinus oedicnemus), Black-winged Stilt (Himantopus himantopus), Collared Pratincole (Glareola pratincola), Mediterranean Gull (Larus melanocephalus), Little Tern (Sternula albifrons), Whiskered Tern (Chlidonias hybrida), Eurasian Roller (Coracias garrulus) and Eurasian Jackdaw (Corvus monedula). In addition to records from Hungary, for Black-headed Gull (Larus ridibundus) and Mediterranean Gull I also present observations from Slovakia, and for Common Shelduck (Tadorna tadorna) from Germany.

Low Frequencies of Supernormal Clutches in the Southern Dunlin and the Temminck's Stint

Supernormal clutches are found across bird species. Such clutches often result from more than one female laying eggs in the same nest and can reflect different behaviours from parasitism to laying mistakes. Enlarged clutches are readily visible among waders due to a maximum maternal clutch size of four eggs, yet surprisingly little is known about this phenomenon. Since supernormal clutches are rare, large sample sizes are required to reliably quantify their natural frequencies. We used a large dataset to estimate the frequency of supernormal clutches in the polygamous Temminck's Stint Calidris temminckii and the monogamous Southern Dunlin C. alpina schinzii, and examine the timing of supernormal clutches in relation to the general distribution of nest initiation dates. While supernormal clutches were very rare, they were over four times more common in the Temminck's Stint (0.50%, n = 1594) than in the Southern Dunlin (0.11%, n = 2766). Dunlin show among the lowest frequency of supernormal clutches reported for waders. In the Temminck's Stint, supernormal clutches were found in the middle of the season, while in the Southern Dunlin such clutches occurred in late season replacement nests. The higher rate and timing of enlarged clutches in Temminck's Stints probably relates to the lspecies' breeding system, which can include simultaneous courtship of multiple partners, but more work is needed to assess the relative influence of different factors. We argue that intraspecific nest parasitism is unlikely to be a primary reproductive tactic in small sandpipers.

Внутривидовой и межвидовой гнездовой паразитизм у уток на юге Западной Сибири (Северная Кулунда)

Внутривидовой и межвидовой гнездовой паразитизм у уток на юге Западной Сибири (Северная Кулунда)

Using behavioral observations and genetic markers to characterize the flexible reproductive system in an ex situ population of carmine bee-eaters (Merops n. nubicus)

Combining behavioral observations with population genetic analyses in ex situ populations can be used to evaluate factors that determine the success of a breeding program. Avian species living in a colony accrue reproductive benefits by taking advantage of multiple reproductive strategies. Growing evidence suggests that both extra pair fertilizations (EPFs) and intra-specific nest parasitism (ISNP) are sufficiently frequent in colonial birds to produce patterns of relatedness that differ from those inferred from behavioral observations. The aim of this study was to use behavioral and genetic information to examine relatedness and reproductive behaviors in an ex situ colony of Northern carmine bee-eaters (Merops n. nubicus). We conducted behavioral observations to determine social parents (i.e. the males and females that entered/exited each nest with the highest frequency). We also used microsatellite marker to conduct parentage analysis and calculate relatedness between individuals in the colony. Using two methods of parentage analysis, we were able to determine one or both parents of all offspring. Males and females differ in their parental behavior during the different reproductive phases. Finally, both males and females were found to use reproductive strategies other than monogamy. In general, EPFs and ISNP are two of the consequences of social living, with multiple individuals utilizing these various strategies for reproduction. In summary, our study found that Northern carmine bee-eaters use a flexible social system that enables individuals within populations to take advantage of suitable nest conditions and mating strategies as they arise, which allows for some individuals in this ex situ colony to have improved reproductive success.

Using Microsatellite DNA to Understand Bobwhite Behavior and Population Structure (Post Abstract)

Northern bobwhite (Colinus virginianus) have a flexible mating system with varying degrees of parental investment in offspring. Questions of relatedness of mates and the dynamics of covey membership have not been answered. It is not known how different patterns of mating systems impact productivity of bobwhite populations. In addition to behaviors, the genetic structure of bobwhite populations likely varies across landscapes, and may depend on the distribution and abundance of habitat types. These issues have critical conservation and management implications, such as the impact of habitat fragmentation on gene flow. Recent advances in molecular techniques provide an opportunity to investigate these questions through examination of small, repetitive, highly variable regions of DNA known as microsatellites. Microsatellites provide the fine-scale resolution needed to objectively understand certain population structures and reproductive strategies. Microsatellite analysis techniques have been used successfully to research relatedness and extra-pair paternity of a number of species. Therefore, we have begun to investigate the genetic basis for many northern bobwhite behaviors related to reproduction. Our primary objectives are to determine: (1) relatedness of individuals within coveys and groups over time, (2) relatedness between reproductive pairs relative to random pairings, (3) relatedness of chicks in broods, (4) rates of extrapair fertilization, (5) rates of intra-specific nest parasitism, and (6) the relatedness of incubating birds to their eggs. To do so, we have developed a series of microsatellite markers for northern bobwhites. We radiomarked approximately 75% of bobwhites on our study area at Tall Timbers Research Station. We collected body feathers from adults and 1.5 mm patagial micro-biopsies from each chick (4 days old) found brooding with radiomarked adults for microsatellite analysis. We are determining relatedness and parentage, based on these microsatellite data, using programs RELATEDNESS and CERVUS. Additionally, we are testing our tissue collection techniques on a pen-reared population of bobwhites to determine the efficiency of DNA amplification via the polymerase chain reaction for 4 tissue collection techniques: patagial micro-biopsy, down and feather shaft, egg tooth, and egg membrane. Additionally, we are pairing pen-reared adult hens and males for different periods of time to determine the presence of sperm storage and test for evidence of sperm competition. Further, we are crossing individuals of known relatedness over several generations to test the accuracy of paternity inferences calculated by CERVUS with respect to bobwhite microsatellite data. Finally, by collecting feathers from hunterkilled bobwhites throughout the Red Hills and the southeast, we will compare the genetic structure of the bobwhite population(s) of the Red Hills, likely the last panmictic population in the southeast, to more isolated, declining populations. In our poster we present a detailed description of this research along with first year results.

Transfer of maternal antibodies against avian influenza virus in mallards (Anas platyrhynchos).

Maternal antibodies protect chicks from infection with pathogens early in life and may impact pathogen dynamics due to the alteration of the proportion of susceptible individuals in a population. We investigated the transfer of maternal antibodies against avian influenza virus (AIV) in a key AIV host species, the mallard (Anas platyrhynchos). Combining observations in both the field and in mallards kept in captivity, we connected maternal AIV antibody concentrations in eggs to (i) female body condition, (ii) female AIV antibody concentration, (iii) egg laying order, (iv) egg size and (v) embryo sex. We applied maternity analysis to the eggs collected in the field to account for intraspecific nest parasitism, which is reportedly high in Anseriformes, detecting parasitic eggs in one out of eight clutches. AIV antibody prevalence in free-living and captive females was respectively 48% and 56%, with 43% and 24% of the eggs receiving these antibodies maternally. In both field and captive study, maternal AIV antibody concentrations in egg yolk correlated positively with circulating AIV antibody concentrations in females. In the captive study, yolk AIV antibody concentrations correlated positively with egg laying order. Female body mass and egg size from the field and captive study, and embryos sex from the field study were not associated with maternal AIV antibody concentrations in eggs. Our study indicates that maternal AIV antibody transfer may potentially play an important role in shaping AIV infection dynamics in mallards.

New record of intraspecific nest parasitism by the Silky Starling (Sturnus sericeus)

The Silky Starling (Sturnus sericeus) is endemic to East Asia and little is know about its’ breeding ecology. We found intraspecific nest parasitism (INP) by this species in a reproductive study conducted from March to June 2011. We found three nests were parasitized using the obvious morphological differences or partition of egg-laying. One egg appeared 3 days after the 26th female had finished laying eggs. One egg was different in color from the other five eggs in the 27th nest. The third instance was discovered in the 37th nest after the fledglings had fledged. Our findings confirmed INP by the Silky Starling.

New record of intraspecific nest parasitism by the Silky Starling (Sturnus sericeus)

The Silky Starling ( Sturnus sericeus ) is endemic to East Asia and little is know about its’ breeding ecology. We found intraspecific nest parasitism (INP) by this species in a reproductive study conducted from March to June 2011. We found three nests were parasitized using the obvious morphological differences or partition of egg-laying. One egg appeared 3 days after the 26th female had finished laying eggs. One egg was different in color from the other five eggs in the 27th nest. The third instance was discovered in the 37th nest after the fledglings had fledged. Our findings confirmed INP by the Silky Starling.

The secret sex lives of sage-grouse: multiple paternity and intraspecific nest parasitism revealed through genetic analysis

In lek-based mating systems only a few males are expected to obtain the majority of matings in a single breeding season and multiple mating is believed to be rare. We used 13 microsatellites to genotype greater sage-grouse (Centrocercus urophasianus) samples from 604 adults and 1206 offspring from 191 clutches (1999–2006) from Alberta, Canada, to determine paternity and polygamy (males and females mating with multiple individuals). We found that most clutches had a single father and mother, but there was evidence of multiple paternity and intraspecific nest parasitism. Annually, most males fathered only one brood, very few males fathered multiple broods, and the proportion of all sampled males in the population fathering offspring averaged 45.9%, suggesting that more males breed in Alberta than previously reported for the species. Twenty-six eggs (2.2%) could be traced to intraspecific nest parasitism and 15 of 191 clutches (7.9%) had multiple fathers. These new insights have important implications on what we know about sexual selection and the mating structure of lekking species. Key wor ds: lek, multiple paternity, nest parasitism, paternity, polygyny, sage-grouse. [Behav Ecol]

Isolation and characterization of microsatellite loci from blue-footed boobies (Sula nebouxii)

Blue-footed boobies (Sula nebouxii) are socially monogamous, colonial seabirds exhibiting intra-specific nest parasitism and extra-pair copulations. Prior DNA fingerprinting assays failed to detect extra-pair offspring in the nests of congeners, and the rate of intra-specific nest parasitism has not been estimated using molecular techniques. We describe the development and characterization of 11 microsatellite DNA loci, tested using 31 individuals collected on Isla Isabel, Nayarit, Mexico. The number of alleles per locus ranged from three to 22, averaging seven; total exclusionary power of the microsatellite panel was 0.99; no loci deviated from Hardy-Weinberg equilibrium; and we did not detect linkage disequilibrium following Bonferroni correction. This microsatellite panel will facilitate future studies of nest parasitism and extra-pair paternity in blue-footed boobies.

Nesting Ecology of Red-Breasted Mergansers in a Common Tern Colony in Eastern New Brunswick

Nest-site selection and nest success for Red-breasted Mergansers (Mergus serrator) breeding on a barrier island complex (Tern Islands) with >10,000 Common Terns (Sterna hirundo) in eastern New Brunswick, Canada, were studied in 2005 and 2006. Concealment was the most important feature for nest placement as 153 of 156 nests were in dense stands of Marram Grass (Ammophila breviligulata), and overhead concealment, vegetation density and vegetation height were all greater at nests than at random locations. Apparent success for all nests was 57% and was similar between years. Few nests were depredated (N = 3), but abandonment was responsible for 95% of nest losses and was most common early in the season. Nest success was <45% for nests initiated before 25 May but >75% for nests initiated after 10 June. Nest abandonment was influenced by intraspecific nest parasitism and investigator activity. Red-breasted Mergansers selected nest sites adaptively on Tern Islands because: 1) nests were more concealed than random sites; 2) avian predation at nests in the Common Tern colony was lower than at nests on nearby islands without terns; 3) nests were not exposed to mammalian predators; and 4) nest success and nest densities were high.

Egg Morphology Is An Unreliable Indicator of Intraspecific Nest Parasitism in Wood Ducks

Abstract. We examined the utility of the maximum Euclidean distance (MED) method, which was developed for the Common Goldeneye (Bucephala clangula) and is based on egg morphology, to detect parasitism in the Wood Duck (Aix sponsa). We used five polymorphic microsatellite loci to identify parasitized clutches and contributions by multiple females. Three-egg clutches randomly assembled from eggs of one female were less variable than those of three females, indicating that variation within females was less than variation among females. Although variation in egg morphology in parasitized clutches was greater than among eggs laid by one female, extensive overlap in MED values precluded the identification of a clear boundary to distinguish between parasitized and unparasitized clutches. The best MED criterion misclassified 28% of nests. Our results suggest that egg morphology should not be used to detect parasitism in Wood Ducks.

Intraspecific nest parasitism and nest guarding in the Pied Flycatcher Ficedula hypoleuca

Intraspecific nest parasitism and nest guarding in the Pied Flycatcher Ficedula hypoleuca

Isolation and characterization of polymorphic microsatellites isolated from the spotless starling (Sturnus unicolor) and cross‐species amplification in the European starling (Sturnus vulgaris)

AbstractSpotless and European starlings (Sturnus unicolor and Sturnus vulgaris) have attracted attention from researchers interested in sexual selection, evolution of parental care and reproductive strategies. Both species show high levels of intraspecific nest parasitism and extra‐pair paternity, but research in this area is hampered by a lack of molecular markers specific for these species. Here, we describe a set of primers for nine microsatellite loci in spotless starlings, eight of which are highly polymorphic (7.37 alleles in average). These microsatellites are also polymorphic in European starlings (6.75 alleles in average).

Intraspecific nest parasitism of cavity-nesting wood ducks: costs and benefits to hosts and parasites

Intraspecific nest parasitism may have few costs to hosts in species with precocial young and limited parental care. We examined costs and benefits of parasitism to hosts and parasites in wood ducks, Aix sponsa. Hosts laid fewer eggs when parasitized, although host egg laying was not related to the number of parasite eggs in a nest. The proportion of eggs that hatched declined with increasing clutch size; most unhatched eggs were laid by parasites. Hatching success of host eggs was not affected by parasitism. Incubation length also increased with clutch size, which prolonged nest exposure to predators, although simulations predicted that this was offset by dilution of predation risk. However, longer incubation potentially posed energetic costs. For a wide range of parasitism levels, this energetic cost was low compared to the costs of laying a replacement clutch. Therefore, abandonment was favourable only when nests were heavily parasitized early in the laying period, which was consistent with observations. Inclusive fitness benefits were possible for hosts if hosts and parasites were related. Modelling costs and benefits from the parasite's perspective, the cost of lower hatching success was more than offset by the benefits of avoiding incubation. For females that incubated a nest and parasitized another female's nest, allocation of eggs between nests was influenced by the cost of incubating an additional egg, the cost of lower hatching success of parasitically laid eggs, and any dilution of predation risk for parasitically laid eggs. These findings help to explain the high prevalence of intraspecific nest parasitism in precocial birds.

Intraspecific Nest Parasitism of Wood Ducks in Natural Cavities: Comparisons with Nest Boxes

Abstract Wood duck (Aix sponsa) hens are known to lay eggs in nests of other wood ducks. Low levels of intraspecific nest parasitism can increase the number of ducklings produced, but at high levels, increased numbers of eggs are offset by reduced hatching success and elevated nest abandonment. Such effects have been observed in nest boxes, stimulating interest in the role of intraspecific nest parasitism in natural cavities. We found high rates of nest parasitism (85% of nests) in natural cavities by applying microsatellite genetic markers to examine maternity for clutches laid in floodplain and upland forests. Clutch sizes, number of parasites per nest, and the number of parasitic eggs deposited per nest were greater in tree cavities located in floodplain than in upland forests (35.2%, 63.6%, 75.0% greater, respectively; P < 0.05), although the proportions of nests parasitized were similar (100% of floodplain nests versus 80% of upland nests, P = 0.11). We compared our data to almost 40 years of publish...