Normal Electrocardiographic Pattern in Conscious Healthy Domestic Geese (Anser anser).

The aim of this study was to describe the reference intervals of electrocardiographic patterns and values in conscious healthy domestic geese (Anser anser). Standard bipolar and augmented unipolar limb lead electrocardiograms with a direct writing electrocardiograph were recorded in 14 domestic geese. The durations of PR interval, QRS complex, ST and QT intervals, the net of the QRS complex, and the P and T amplitudes were determined at 50 mm/s and at 1 cm = 1 mV. The polarity waveform was examined. The mean electrical axis in the frontal plane was determined in leads II and III. Data are expressed as means and standard deviations. The mean (SD) heart rate was 153.8 (22.4) beats/min. The QRS complex was mainly negative in leads II and III; it was positive in the augmented vector right, augmented vector left, and augmented vector foot leads. The T wave was positive in leads II, III, and the augmented vector foot lead and was negative in the augmented vector right and left leads. The mean electrical axis ranged between -30° to -140°. Electrocardiogram recordings were well tolerated by the geese. The reference intervals provided here can be used to assist in the interpretation of electrocardiographic patterns in geese.

Diabetes Mellitus With Concurrent Cerebellar Degeneration and Necrosis in a Domestic Goose ( Anser anser domesticus).

A 5-year-old sexually intact male Toulouse goose ( Anser anser domesticus) was presented for ataxia, polyuria, and polydipsia. The goose was cachectic and exhibited head tremors. Results of plasma biochemical analysis and point-of-care glucometry revealed persistent hyperglycemia. Despite supportive care and oral glipizide, the goose died within 48 hours of presentation. Necropsy revealed severe pancreatic atrophy and fibrosis with regionally extensive cerebellar encephalomalacia and generalized Purkinje cell degeneration and necrosis. On a wet basis, hepatic zinc concentration was determined to be twice the reference interval by atomic absorption spectroscopy. Based on these findings, the pancreatic insufficiency with secondary diabetes mellitus was attributed to chronic zinc toxicosis. Despite birds' relative resistance to high blood glucose concentrations, prolonged hyperglycemia is suspected to have caused selective Purkinje cell degeneration and necrosis by glial activation, mitochondrial dysfunction, and glutamate toxicity, which resulted in the clinically observed motor deficits. This is consistent with experimental diabetic rat models. This case highlights the need for further investigation of the complex pathophysiology of diabetes mellitus in birds.

Repair of a Tibiotarsal Fracture in a Pomeranian Goose ( Anser anser) With a Locking Plate.

A 2-year-old Pomeranian goose ( Anser anser) weighing 8.1 kg was examined because of non-weight-bearing lameness of the right limb. A closed, transverse, diaphyseal fracture of the distal third of the right tibiotarsus with a craniolateral displacement of the distal fragment was diagnosed radiographically. Surgery under general anesthesia was performed to repair the fracture with a 14-hole, 2.7-mm locking plate fixed with 6 screws in a bicortical manner. Two days later, the bird was fully weight-bearing on the leg. Radiographs performed 4 and 8 weeks after surgery showed good healing of the affected bone with an appropriate callus formation bridging the fracture line. Sixteen weeks after surgery, the patient was readmitted because of lameness exhibited while staying outside exposed to subzero (°C) temperatures. On the basis of this finding, heat conduction was postulated as the possible cause of lameness because it disappeared after implant removal. To the best our knowledge, this case represents the first report of a surgical repair of a tibiotarsal fracture with a locking plate in waterfowl.

Quantifying the expected value of uncertain management choices for over-abundant Greylag Geese.

In many parts of the world, conservation successes or global anthropogenic changes have led to increasing native species populations that then compete with human resource use. In the Orkney Islands, Scotland, a 60-fold increase in Greylag Goose Anser anser numbers over 24 years has led to agricultural damages and culling attempts that have failed to prevent population increase. To address uncertainty about why populations have increased, we combined empirical modelling of possible drivers of Greylag Goose population change with expert-elicited benefits of alternative management actions to identify whether to learn versus act immediately to reduce damages by geese. We built linear mixed-effects models relating annual goose densities on farms to land-use and environmental covariates and estimated AICc model weights to indicate relative support for six hypotheses of change. We elicited from experts the expected likelihood that one of six actions would achieve an objective of halting goose population growth, given each hypothesis for population change. Model weights and expected effects of actions were combined in Value of Information analysis (VoI) to quantify the utility of resolving uncertainty in each hypothesis through adaptive management and monitoring. The action with the highest expected value under existing uncertainty was to increase the extent of low quality habitats, whereas assuming equal hypothesis weights changed the best action to culling. VoI analysis showed that the value of learning to resolve uncertainty in any individual hypothesis for goose population change was low, due to high support for a single hypothesis of change. Our study demonstrates a two-step framework that learns about the most likely drivers of change for an over-abundant species, and uses this knowledge to weight the utility of alternative management actions. Our approach helps inform which strategies might best be implemented to resolve uncertainty when there are competing hypotheses for change and competing management choices.

Relationship between wild greylag and European domestic geese based on mitochondrial DNA.

The origins of the European domestic goose are uncertain. The available information comes from archaeological findings and historical literature, but genetic evidence has hitherto been scarce. The domestic goose in Europe is derived from the greylag goose (Anser anser), but it is not known where the initial domestication took place and which of the two subspecies of greylag goose was ancestral. We aimed to determine the amount and geographical distribution of genetic diversity in modern populations of greylag geese as well as in different breeds of the domestic goose to make inferences about goose domestication. We studied DNA sequence variation in the mitochondrial control region of greylag geese from multiple populations across Europe and western Asia as well as specimens of domestic geese representing 18 modern breeds and individuals not belonging to any recognised breed. Our results show notable differences in genetic diversity between different greylag goose populations and the presence of six mitochondrial haplogroups which show a degree of geographical partitioning. The genetic diversity of the domestic goose is low, with 84% of sampled individuals having one of two major closely related haplotypes, suggesting that modern European domestic geese may derive from a narrow genetic base. The site of domestication remains unresolved, but domestic geese in Turkey were unusually diverse, indicating the importance of further sampling in the vicinity of the eastern Mediterranean and the Near East. There appears to be past or ongoing hybridisation between greylags and domestic geese in particular areas, consistent with field observations.

Chromosome-level genome sequencing and multi-omics of the Hungarian White Goose (Anser anser domesticus) reveals novel miRNA-mRNA regulation mechanism of waterfowl feather follicle development.

The Hungarian White Goose (Anser anser domesticus) is an excellent European goose breed, with high feather and meat production. Despite its importance in the poultry industry, no available genome assembly information has been published. This study aimed to present Chromosome-level and functional genome sequencing of the Hungarian White Goose. The results showed that the genome assembly has a total length of 1115.82 Mb, 39 pairs of chromosomes, 92.98% of the BUSCO index, and contig N50 and scaffold N50 were up to 2.32 Mb and 60.69 Mb, respectively. Annotation of the genome assembly revealed 19550 genes, 286 miRNAs, etc. We identified 235 expanded and 1,167 contracted gene families in this breed compared with the other 16 species. We performed a positive selection analysis between this breed and four species of Anatidae to uncover the genetic information underlying feather follicle development. Further, we detected the function of miR-199-x, miR-143-y, and miR-23-z on goose embryonic skin fibroblast. In summary, we have successfully generated a highly complete genome sequence of the Hungarian white goose, which will provide a great resource to improve our understanding of gene functions and enhance the studies on feather follicle development at the genomic level.

Population Structure and Selection Signatures of Domestication in Geese.

The goose is an economically important poultry species and was one of the first to be domesticated. However, studies on population genetic structures and domestication in goose are very limited. Here, we performed whole genome resequencing of geese from two wild ancestral populations, five Chinese domestic breeds, and four European domestic breeds. We found that Chinese domestic geese except Yili geese originated from a common ancestor and exhibited strong geographical distribution patterns and trait differentiation patterns, while the origin of European domestic geese was more complex, with two modern breeds having Chinese admixture. In both Chinese and European domestic geese, the identified selection signatures during domestication primarily involved the nervous system, immunity, and metabolism. Interestingly, genes related to vision, skeleton, and blood-O2 transport were also found to be under selection, indicating genetic adaptation to the captive environment. A forehead knob characterized by thickened skin and protruding bone is a unique trait of Chinese domestic geese. Interestingly, our population differentiation analysis followed by an extended genotype analysis in an additional population suggested that two intronic SNPs in EXT1, an osteochondroma-related gene, may plausibly be sites responsible for knob. Moreover, CSMD1 and LHCGR genes were found to be significantly associated with broodiness in Chinese domestic geese and European domestic geese, respectively. Our results have important implications for understanding the population structure and domestication of geese, and the selection signatures and variants identified in this study might be useful in genetic breeding for forehead knob and reproduction traits.

DRD4 allele frequencies in greylag geese vary between urban and rural sites.

With the increasing urbanization of the last decades, more and more bird species occur in urban habitats. Birds which thrive in urban habitats often have a higher tolerance toward human disturbance and show behaviors which differ from their rural counterparts. There is increasing evidence that many behaviors have a genetic basis. One candidate gene is the dopamine receptor D4 (DRD4), which has been associated with fear and thus, flight initiation distance (FID). In this study, we analyzed a segment of DRD4 in greylag geese Anser anser, describing the variability of this gene across several geographically distant populations, and comparing its variability between an urban and a rural site in south-west Germany. We additionally measured FIDs of urban and rural geese to test for a possible correlation with DRD4 genotypes. We found a high variation within DRD4, with 10 variable sites leading to 11 alleles and 35 genotypes. Two genotypes occurred in 60% of all geese and were thus defined as common genotypes versus 33 rare genotypes. Population differentiation was very low between the urban and rural sites in Germany but common genotypes occurred more often in the urban area and rare genotypes more often in the rural area. FID was significantly higher at the rural site, but no significant correlation between FID and DRD4 genotypes could be detected. Nevertheless, our results suggest that local site selection may be related to DRD4 genotypes.

Lucilia sericata (Diptera: Calliphoridae) as Agent of Myiasis in a Goose in Italy and a Review of Myiasis by This Species in Birds.

Myiasis is a type of parasitosis by larvae of Diptera that may affect vertebrates, including wild and domestic birds. Traumatic myiasis was discovered in a domestic goose, Anser anser domesticus L. (Anseriformes: Anatidae), in June 2020 in a rural area of the region Calabria (Southern Italy). The myiasis was caused by Lucilia sericata (Meigen) (Diptera: Calliphoridae). In Italy, this was the first case of myiasis by L. sericata ever described in a bird. It was also the first case of myiasis detected in a goose in Italy. The description of the case is integrated by a discussion on nonhematophagous dipteran larvae causing myiasis in birds and by an updated and detailed review of literature cases of myiasis by L. sericata in birds reported worldwide, useful for monitoring and management of dipteran species of medical and veterinary interest.

Leapfrog migration and residents: New migratory habits in Swedish Greylag geese.

Knowledge about intraspecific and individual variation in bird migration behavior is important to predict spatiotemporal distribution, patterns of phenology, breeding success, and interactions with the surrounding environment (e.g., human livelihoods). Such variation is key to adaptive, evolutionary responses, i.e., how individuals respond spatiotemporally to the environment to maximize fitness. In this study we used GPS location data from one to three full annual cycles from 76 Greylag geese (Anser anser) to test the hypothesis that geese originating at five latitudinally separated capture sites in Sweden have different migration strategies. We also assessed individual consistency in movement strategy over consecutive annual cycles. We used the scale-independent net squared displacement modeling framework to quantify variables of autumn and spring migration for geese from each capture site: distance, timing, and duration. Our results demonstrate a positive correlation between migration distance and latitudinal origin. Geese from the northernmost site on average migrated farther south and about 15 times as far as the short-moving or resident geese from the two southernmost sites. Movement strategies of individual geese varied considerably both within and among capture sites. Individual consistency in movement strategy from one annual cycle to the consecutive was high in geese from the northern sites moving the farthest, whereas the resident or short-moving geese from the southernmost sites generally showed lower or no individual consistency. These changes have come about during a time span so short (i.e., ca. 35 years or 8-10 generations) that it can unlikely be explained by classical Darwinian between-generation adaptation. Consequently, and given that young geese follow their parents during their first migration, we presume an important role of within-family, inter-generation change as a driver behind the large-scale changed migration habits in Swedish Greylag geese.

Corticosterone: foraging and fattening puppet master in pre-breeding greylag geese.

Reproduction is one of the most energetically costly life history stages, which impose constraints, even outside the breeding period. Capital breeders typically accumulate energy in preparation for reproduction and the amount of body mass gain prior to reproduction partly determines reproductive outcome in such species. Understanding the physiological and behavioral interplay that governs energy storage is thus essential. Pleiotropic hormones such as glucocorticoids can modulate diel and seasonal energy allocation in vertebrates. Baseline corticosterone (CORT, the main glucocorticoid hormone in birds) fluctuation can induce changes in foraging behavior and/or energy storage. In this experiment, we slightly elevated CORT levels and monitored body mass and foraging behavior prior to reproduction in semi-captive greylag geese. Birds treated either with CORT or placebo pellets inserted subcutaneously were monitored during 21 days. Same individuals were sequentially submitted to both treatments. The increase of CORT levels measured in blood samples confirmed the slight CORT elevation in treated birds. Foraging behaviors increased (up to 9%) in the CORT treated group compared to controls only during morning observations. Birds treated with CORT increased their body mass gain by 6.3% compared to controls. This effect lasted during the first 11 days after pellet implementation. We thus confirm the central role of glucocorticoids on foraging behaviors and body mass gain in pre-nesting birds. This study opens new avenues to manipulate body condition in large-bird species.

The intestinal microbial composition in Greylag geese differs with steatosis induction mode: spontaneous or induced by overfeeding.

BACKGROUND: Relationships between microbial composition and steatosis are being extensively studied in mammals, and causal relations have been evidenced. In migratory birds the liver can transiently store lipids during pre-migratory and migratory phases, but little is known about the implications of the digestive microbiota in those mechanisms. The Landaise greylag goose (Anser anser) is a good model to study steatosis in migratory birds as it is domesticated, but is still, from a genetic point of view, close to its wild migratory ancestor. It also has a great ingestion capacity and a good predisposition for hepatic steatosis, whether spontaneous or induced by conventional overfeeding. The conventional (overfeeding) and alternative (spontaneous steatosis induction) systems differ considerably in duration and feed intake level and previous studies have shown that aptitudes to spontaneous steatosis are very variable. The present study thus aimed to address two issues: (i) evaluate whether microbial composition differs with steatosis-inducing mode; (ii) elucidate whether a digestive microbial signature could be associated with variable aptitudes to spontaneous liver steatosis. RESULTS: Performances, biochemical composition of the livers and microbiota differed considerably in response to steatosis stimulation. We namely identified the genus Romboutsia to be overrepresented in birds developing a spontaneous steatosis in comparison to those submitted to conventional overfeeding while the genera Ralstonia, Variovorax and Sphingomonas were underrepresented only in birds that did not develop a spontaneous steatosis compared to conventionally overfed ones, birds developing a spontaneous steatosis having intermediate values. Secondly, no overall differences in microbial composition were evidenced in association with variable aptitudes to spontaneous steatosis, although one OTU, belonging to the Lactobacillus genus, was overrepresented in birds having developed a spontaneous steatosis compared to those that had not. CONCLUSIONS: Our study is the first to evaluate the intestinal microbial composition in association with steatosis, whether spontaneous or induced by overfeeding, in geese. Steatosis induction modes were associated with distinct digestive microbial compositions. However, unlike what can be observed in mammals, no clear microbial signature associated with spontaneous steatosis level was identified.

Long-Term Reciprocal Gene Flow in Wild and Domestic Geese Reveals Complex Domestication History.

Hybridization has frequently been observed between wild and domestic species and can substantially impact genetic diversity of both counterparts. Geese show some of the highest levels of interspecific hybridization across all bird orders, and two of the goose species in the genus Anser have been domesticated providing an excellent opportunity for a joint study of domestication and hybridization. Until now, knowledge of the details of the goose domestication process has come from archaeological findings and historical writings supplemented with a few studies based on mitochondrial DNA. Here, we used genome-wide markers to make the first genome-based inference of the timing of European goose domestication. We also analyzed the impact of hybridization on the genome-wide genetic variation in current populations of the European domestic goose and its wild progenitor: the graylag goose (Anser anser). Our dataset consisted of 58 wild graylags sampled around Eurasia and 75 domestic geese representing 14 breeds genotyped for 33,527 single nucleotide polymorphisms. Demographic reconstruction and clustering analysis suggested that divergence between wild and domestic geese around 5,300 generations ago was followed by long-term genetic exchange, and that graylag populations have 3.2-58.0% admixture proportions with domestic geese, with distinct geographic patterns. Surprisingly, many modern European breeds share considerable (> 10%) ancestry with the Chinese domestic geese that is derived from the swan goose Anser cygnoid We show that the domestication process can progress despite continued and pervasive gene flow from the wild form.

The role of CTNNB1 and LEF1 in feather follicles development of Anser cygnoides and Anser anser.

BACKGROUND: Wingless-types/beta-catenin (Wnt/ß-catenin) signaling pathway is one of the most extensively studied transcriptional cascades involved in various types of organogenesis including embryonic and postnatal development. Downy feather quantity is primarily affected by follicular development and gene regulations. OBJECTIVE: This research was aimed to investigate the role of catenin beta-1(CTNNB1) and lymphoid enhancerbinding factor-1 (LEF1) on feather follicles development at different developmental stages. METHODS: Fluorescence quantitative PCR, Western-blot and immunohistochemical methods were used in Anser cygnoides and Anser anser embryos (E12, E13 E18, and E28) and after birth gosling stages (G18, G48, G88) for gene expression analysis. RESULTS: CTNNB1 and LEF1 genes were expressed in Anser cygnoides and Anser anser at different embryonic and after-birth gosling developmental stages and the expression levels were significantly different in different stages (p < 0.05). The mRNA expression of CTNNB1 and LEF1 genes reached the highest level at D88 in Anser cygnoides, while the highest expression levels were at D18 and D88 in Anser anser, and the expression levels of CTNNB1 genes at D88 in all embryonic stages were significantly lower than after-birth stages. CTNNB1 and LEF1 protein expression were the highest at E12 and E28 for Anser cygnoides feather follicles development. While at a similar stage for Anser anser, the expression of CTNNB1 and LEF1 protein was the highest at D48 and D18. Protein expression at embryonic stages was in the epidermis (E) and the hair basal plate (P), the expression site for after-birth stages was in the dermal papilla (DP). CONCLUSION: Our study illustrated that CTNNB1 and LEF1 has an impact on Anser cygnoides and Anser anser feather follicles growth and development.

Annual migratory patterns of Far East Greylag Geese (Anser anser rubrirostris) revealed by GPS tracking.

Twenty Far East Greylag Geese, Anser anser rubrirostris, were captured and fitted with Global Positioning System/Global System for Mobile Communications (GPS/GSM) loggers to identify breeding and wintering areas, migration routes and stopover sites. Telemetry data for the first time showed linkages between their Yangtze River wintering areas, stopover sites in northeastern China, and breeding/molting grounds in eastern Mongolia and northeast China. 10 of the 20 tagged individuals provided sufficient data. They stopped on migration at the Yellow River Estuary, Beidagang Reservoir and Xar Moron River, confirming these areas as being important stopover sites for this population. The median spring migration duration was 33.7 days (individuals started migrating between 25 February and 16 March and completed migrating from 1 to 9 April) compared to 52.7 days in autumn (26 September-13 October until 4 November-11 December). The median stopover duration was 31.1 and 51.3 days and the median speed of travel was 62.6 and 47.9 km/day for spring and autumn migration, respectively. The significant differences between spring and autumn migration on the migration duration, the stopover duration and the migration speed confirmed that tagged adult Greylag Geese traveled faster in spring than autumn, supporting the hypothesis that they should be more time-limited during spring migration.

Site selection by geese in a suburban landscape.

BACKGROUND: In European and North American cities geese are among the most common and most visible large herbivores. As such, their presence and behaviour often conflict with the desires of the human residents. Fouling, noise, aggression and health concerns are all cited as reasons that there are "too many". Lethal control is often used for population management; however, this raises questions about whether this is a sustainable strategy to resolve the conflict between humans and geese when, paradoxically, it is humans that are responsible for creating the habitat and often providing the food and protection of geese at other times. We hypothesise that the landscaping of suburban parks can be improved to decrease its attractiveness to geese and to reduce the opportunity for conflict between geese and humans. METHODS: Using observations collected over five years from a botanic garden situated in suburban Belgium and data from the whole of Flanders in Belgium, we examined landscape features that attract geese. These included the presence of islands in lakes, the distance from water, barriers to level flight and the size of exploited areas. The birds studied were the tadornine goose Alopochen aegyptiaca (L. 1766) (Egyptian goose) and the anserine geese, Branta canadensis (L. 1758) (Canada goose), Anser anser (L. 1758) (greylag goose) and Branta leucopsis (Bechstein, 1803) (barnacle goose). Landscape modification is a known method for altering goose behaviour, but there is little information on the power of such methods with which to inform managers and planners. RESULTS: Our results demonstrate that lakes with islands attract more than twice as many anserine geese than lakes without islands, but make little difference to Egyptian geese. Furthermore, flight barriers between grazing areas and lakes are an effective deterrent to geese using an area for feeding. Keeping grazing areas small and surrounded by trees reduces their attractiveness to geese. CONCLUSION: The results suggest that landscape design can be used successfully to reduce the number of geese and their conflict with humans. However, this approach has its limitations and would require humans to compromise on what they expect from their landscaped parks, such as open vistas, lakes, islands and closely cropped lawns.

Parental behaviour and family proximity as key to gosling survival in Greylag Geese (Anser anser).

Reproductive success in monogamous species is generally affected by both behavioural and hormonal fine-tuning between pair partners. Vigilance, defence and brooding of offspring are among the main parental investments, and often the sexes adopt different roles. In the present study, we investigate how sex differences in parental behaviour and family proximity in the socially monogamous Greylag Goose (Anser anser) affect gosling survival. During the reproductive season in spring 2013, we recorded the behaviour of 18 pairs with offspring and gosling survival in a semi-tame, long-term monitored, and individually marked flock of Greylag Geese in Grünau, Austria. We found that behavioural role differentiation between the parents varied with developmental phase, and thus with gosling age. Especially during the first 10 days after hatching, females were foraging more frequently than males, which were more vigilant and aggressive towards other flock members. Such differences between the sexes levelled out 20 to 30 days after hatching. In general, females stayed in closer proximity to their offspring than males. Gosling survival was high when the parents were relatively aggressive and emphasized vigilance rather than foraging behaviour. Hence, we show a direct link between pair partners' quality of parental investment and gosling survival.

The histological structure and histochemistry of the mucosa of the nasal conchae in geese, Anser anser.

We investigated the histological structure and histochemistry of the nasal conchae of geese and compared these structures with those of other avian species. The rostral, middle and caudal conchae were dissected from the nasal cavity of eight geese, fixed in Carnoy's solution and embedded in paraffin. The entrance of the rostral concha was lined by keratinized stratified squamous epithelium, which toward the middle concha was replaced by modified keratinized squamous epithelium, the deep layer of which opened into tubular glandular structures containing secretory epithelium on crypt-like invaginations. The lamina propria of the rostral concha contained numerous Grandry's and Herbst corpuscles, which are pressure-sensitive receptors peculiar to waterfowl. The lamina propria of the middle concha contained solitary lymphoid follicles and lymphocyte infiltrations. The cartilaginous component of the middle concha was highly convoluted and resembled a spiral of two and a half scrolls, which were lined by pseudostratified columnar epithelium. We observed that unlike mammals, this epithelium contained mostly intraepithelial alveolar glands rather than goblet cells. The caudal concha was similar to the middle concha, but less convoluted. It was lined by olfactory epithelium and its lamina propria contained serous Bowman's glands as well as olfactory nerve fibers. Histochemical examination demonstrated that while none of the conchae contained sulfated mucins, except for the cartilage, the intraepithelial glands of the rostral and middle conchae contained mostly carboxylated acidic mucin and some neutral mucin, and were thus of the mixed type. The outermost scroll of the spiral of the middle concha contained some periodate-Schiff stained mucins. Of the glands of the mucosa of the middle concha, the deep tubuloalveolar glands in the convex parts of the scrolls contained primarily acidic mucins, while the shallow intraepithelial alveolar glands in the concave parts of the scrolls contained primarily neutral mucins. Our findings indicate that the rostral and caudal conchae primarily have a sensory function and the middle concha participates in mucosal defense.

High Grazing Pressure of Geese Threatens Conservation and Restoration of Reed Belts.

Reed (Phragmites australis (Cav.) Trin. ex Steud.) beds are important habitat for marsh birds, but are declining throughout Europe. Increasing numbers of the native marsh bird, the Greylag goose (Anser anser L.), are hypothesized to cause reed bed decline and inhibit restoration of reed beds, but data are largely lacking. In this study, we experimentally tested the effect of grazing by Greylag geese on the growth and expansion of reed growing in belts along lake shorelines. After 5 years of protecting reed from grazing with exclosures, reed stems were over 4-fold denser and taller than in the grazed plots. Grazing pressure was intense with 50-100% of the stems being grazed among years in the control plots open to grazing. After 5 years of protection we opened half of the exclosures and the geese immediately grazed almost 100% of the reed stems. Whereas this did not affect the reed stem density, the stem height was strongly reduced and similar to permanently grazed reed. The next year geese were actively chased away by management from mid-March to mid-June, which changed the maximum amount of geese from over 2300 to less than 50. As a result, reed stem density and height increased and the reed belt had recovered over the full 6 m length of the experimental plots. Lastly, we introduced reed plants in an adjacent lake where no reed was growing and geese did visit this area. After two years, the density of the planted reed was six to nine-fold higher and significantly taller in exclosures compared to control plots where geese had access to the reed plants. We conclude that there is a conservation dilemma regarding how to preserve and restore reed belts in the presence of high densities of Greylag geese as conservation of both reed belts and high goose numbers seems infeasible. We suggest that there are three possible solutions for this dilemma: (1) effects of the geese can be mediated by goose population management, (2) the robustness of the reed marshes can be increased, and (3) at the landscape level, spatial planning can be used to configure landscapes with large reed bed reserves surrounded by unmown, unfertilized meadows.

Over a Thousand Years of Evolutionary History of Domestic Geese from Russian Archaeological Sites, Analysed Using Ancient DNA.

The European domestic goose is a widely farmed species known to have descended from the wild greylag goose (Anser anser). However, the evolutionary history of this domesticate is still poorly known. Ancient DNA studies have been useful for many species, but there has been little such work on geese. We have studied temporal genetic variation among domestic goose specimens excavated from Russian archaeological sites (4th⁻18th centuries) using a 204 base pair fragment of the mitochondrial control region. Specimens fell into three different genetic clades: the domestic D-haplogroup, the F-haplogroup that includes both wild and domestic geese, and a clade comprising another species, the taiga bean goose. Most of the subfossil geese carried typical domestic D-haplotypes. The domestication status of the geese carrying F-haplotypes is less certain, as the haplotypes identified were not present among modern domestic geese and could represent wild geese (misclassified as domestics), introgression from wild geese, or local domestication events. The bones of taiga bean goose were most probably misidentified as domestic goose but the domestication of bean goose or hybridization with domestic goose is also possible. Samples from the 4th to 10th century were clearly differentiated from the later time periods due to a haplotype that was found only in this early period, but otherwise no temporal or geographical variation in haplotype frequencies was apparent.