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Both island species and raptors are at particularly high risk of extinction but few island raptor populations have been the subject of long-term monitoring. To determine trends in abundance in the Christmas Island Boobook, surveys were conducted annually from 2012–2017, in 2019 and in 2022. Across the survey period the population appears to have been either stable or to have increased slightly. Almost no part of the island lacked owls during the most recent survey. The detection rate averaged 1.56 (out of four surveys at a site); it was lowest in 2013 (1.22) and highest in 2022 (2.38). Detection was more likely on nights with low wind, at wetter sites and in closed vegetation, rather than in open or very low vegetation. In a separate analysis on the same data, the top-ranked dynamic occupancy-detection model found that occupancy increased with increasing elevation and vegetation height. No effect of a suspected threat, the presence of invasive yellow crazy ants Anoplolepis gracilipes at a site, could be detected. We recommend ongoing monitoring and research, potentially using automated recording devices and the tracking of individual owls to understand and refine the assumptions underpinning the interpretation of survey results. [ABSTRACT FROM AUTHOR]

Small island populations are vulnerable to genetic decline via demographic and environmental stochasticity. In the absence of immigration, founder effects, inbreeding and genetic drift are likely to contribute to local extinction risk. Management actions may also have a greater impact on small, closed populations. The demographic and social characteristics of a species can, however, delay the impact of threats. K'gari, a ~ 1 660 km2 island off the Australian east coast and UNESCO World Heritage Site (Fraser Island 1842–2023), supports an isolated population of approximately 70–200 dingoes that represent an ideal opportunity to explore the small island paradigm. To examine temporal and spatial patterns of genetic diversity in this population we analysed single nucleotide polymorphism (SNP) genotype data (72 454 SNPS) for 112 K'gari dingoes collected over a 25-year period (1996 to 2020). Genetic diversity was lower in K'gari dingoes than mainland dingoes at the earliest time point in our study and declined significantly following a management cull in 2001. We did not find any spatial genetic patterns on the island, suggesting high levels of genetic connectivity between socially discrete packs. This connectivity, combined with the social structure and behaviour of dingoes, may act in concert to buffer the population from the impacts of genetic drift in the short term. Nevertheless, a general decline in genetic variation via inbreeding and drift has occurred over the past 20 years which we suggest should be considered in any future management planning for the population. Monitoring patterns of genetic variation, together with a clearer understanding of the social ecology of K'gari dingoes, will aid in the development of measurable genetic targets set over ecologically meaningful timelines, and help ensure continued survival of this culturally important population. [ABSTRACT FROM AUTHOR]

The glacial cycles of the Quaternary heavily impacted species through successions of population contractions and expansions. Similarly, populations have been intensely shaped by human pressures such as unregulated hunting and land use changes. White-tailed and mule deer survived in different refugia through the Last Glacial Maximum, and their populations were severely reduced after the European colonization. Here, we analyzed 73 resequenced deer genomes from across their North American range to understand the consequences of climatic and anthropogenic pressures on deer demographic and adaptive history. We found strong signals of climate-induced vicariance and demographic decline; notably, multiple sequentially Markovian coalescent recovers a severe decline in mainland white-tailed deer effective population size (N e) at the end of the Last Glacial Maximum. We found robust evidence for colonial overharvest in the form of a recent and dramatic drop in N e in all analyzed populations. Historical census size and restocking data show a clear parallel to historical N e estimates, and temporal N e/ N c ratio shows patterns of conservation concern for mule deer. Signatures of selection highlight genes related to temperature, including a cold receptor previously highlighted in woolly mammoth. We also detected immune genes that we surmise reflect the changing land use patterns in North America. Our study provides a detailed picture of anthropogenic and climatic-induced decline in deer diversity and clues to understanding the conservation concerns of mule deer and the successful demographic recovery of white-tailed deer. [ABSTRACT FROM AUTHOR]

In this second part of the study, using a ‘clean’ dataset without very low precision landmarks and outliers, I describe how to compare mandibular size and shape using Procrustes methods in adult North American marmots. After demonstrating that sex differences are negligible, females and males are pooled together with specimens of unknown sex and species are compared using a battery of tests, that estimate both statistical significance and effect size. The importance of allometric variation and its potential effect on shape differences is also explored. Finally, to provide potential clues on founder effects, I compare the magnitude of variance in mandibular size and shape between the Vancouver Island marmot (VAN) and the hoary marmot, its sister species on the mainland. In almost all main analyses, I explore the sensitivity of results to heterogeneous sample size and small samples using subsamples and randomized selection experiments. For both size and shape, I find a degree of overlap among species variation but, with very few exceptions, mean interspecific differences are well supported in all analyses. Shape, in particular, is an accurate predictor of taxonomic affiliation. Allometry in adults, however, explains a modest amount of within-species shape change. Yet, there is a degree of divergence in allometric trajectories that seems consistent with subgeneric separation. VAN is the most distinctive species for mandibular shape and mandibular morphology suggests a long history of reduced variation in this insular population. Geometric morphometrics (GMM) is a powerful tool to aid taxonomic research. Regardless of the effectiveness of this family of methods and the apparent robustness of results obtained with GMM, however, large samples and careful measurements remain essential for accuracy. Even with excellent data, morphometrics is important, but its findings must be corroborated with an integrative approach that combines multiple lines of evidence to taxonomic assessment. The analytical protocol I suggest is described in detail, with a summary checklist, in the Appendix, not to miss important steps. All the analyses can be replicated using the entire dataset, which is freely available online. Beginners may follow all the steps, whereas more experienced researchers can focus on one specific aspect and read only the relevant chapter. There are limitations, but the protocol is flexible and easy to improve or implement using a programming language such as R.

Estimation of the population size is essential for understanding population dynamics. Estimating animal density using multiple methods and/or multiple attempts is required for accurate estimations. Raccoon dog Nyctereutes procyonoides is native to East Asia, including Japan, and has become an invasive species in Europe. Information on raccoon dog density in their native range is important to understand their invasion; however, relatively few studies have been conducted on raccoon dog density in their native range. In this study, we extracted DNA from fecal samples of raccoon dogs inhabiting a small island in Japan and conducted density estimation over two periods using DNA capture‐recapture methods: CAPWIRE and SECR. We also investigated sex ratio using genetic sex identification. Density estimates using SECR were approximately threefold different between the two study periods: 17.2 individuals per km2 in 2018 and 49.0 individuals per km2 in 2020. In contrast, estimates using CAPWIRE were relatively stable: 21.7 individuals per km2 in 2018 and 24.3 individuals per km2 in 2020. A drastic increase or decrease is not expected during the study period, and thus, density estimates using CAPWIRE are more reasonable than those using SECR. The small number of samples per individual might result in low accuracy of density estimates by SECR. The density estimated by CAPWIRE was similar to that in the main island in Japan and higher than that in Europe. Feeding competition with other omnivorous carnivores and/or predation risk by wolves might maintain the low density in Europe. The sex ratio of raccoon dogs was 1:1, which was similar to the values in invasive raccoon dogs and other canids. Further genetic census, including sex identification in various landscapes in their native and invasive range, will enable us to understand not only the ecology of raccoon dogs but also their adaptations to their invading areas. [ABSTRACT FROM AUTHOR]

Most Queensland islands today have no koalas, but in the past several islands were inhabited by the iconic marsupial. Using historical research methods, this paper compiles what is known about the arrival of koalas on Queensland islands, both naturally occurring and translocated, and discusses their persistence, current status, environments and threats. Seventeen islands are identified as having a history of koalas with 13 of these islands having once been part of the koala's natural range. Two of these islands with natural populations plus four unoccupied islands received historical translocations as early as the 1920s and 1930s as a conservation tool or to boost tourism. Currently, 7 of the 17 islands still have koalas. For future research, the paper raises the important question about whether some Queensland islands are suitable habitat sanctuaries for koalas for further translocations. [ABSTRACT FROM AUTHOR]

The European mink (Mustela lutreola) is one of the most threatened small carnivores, listed as Critically Endangered on the IUCN Red List. Tallinn Zoo started a conservation breeding operation in 1980, which in 1992 was shaped into the European mink EEP Program to maintain a demographically and genetically healthy population in captivity. Since 2000, mink have been translocated on a yearly basis from the breeding facility in the zoo to Hiiumaa Island (Estonia) until the formation of the wild island population in 2016. Maintaining a healthy genetic structure in a captive population was a priority, so genetically the least valuable animals, according to calculations made by a population management program, were used for translocation. This study aims to assess the amount of genetic diversity passed from an ex situ population on to the island population. Comparisons of the genetic diversity were made by mitochondrial, microsatellite and nuclear markers. In addition, our results were combined with the pedigree data from the European mink EEP Studbook to further evaluate the flow of genetic diversity from the founder population to the established wild population. According to the findings, the island population's allelic richness was comparable to that of the founder population, and no evidence was found that its genetic structure had diverged from that of the founder population. It seems that the formation of the island population has been a gradual process of no more than the last seven yearly translocations. Research highlights: The European mink's Hiiumaa Island population's genetic diversity was comparable to that of the founder population from Tallinn Zoo.It appears that the island population was formed gradually over the course of the past seven yearly translocations. [ABSTRACT FROM AUTHOR]

The raccoon dog (Nyctereutes procyonoides) is a representative of Canidae and is closely related to red fox-like canids, although the species exhibits high distinctiveness in the family. These animals were farmed for fur products, but thousands were intentionally released into the wild in western Russia. This newly established alien species in Europe has spread rapidly into many European countries. The aim of the study was to determine the origin of Polish populations by comparing the mitochondrial molecular marker cytochrome b (cytb) sequences of Polish wild and farm individuals with wild raccoon dogs from the western Russia and Asian specimens whose sequences were obtained from GenBank resources. The results of our phylogenetic analysis support the previous suggestions on the existence of two main clades clearly referring to continental and Island populations. Polish individuals were classified into a highly diverse continental group. The relationships between the haplotypes within the clade together with estimated values of genetic diversity parameters indicate that the Polish raccoon dog populations exhibit high genetic similarity to the Russian population. In combination with the history of introduction of the species to Europe, this suggests the most probable assignment of the Polish populations to the subspecies N. procyonoides ussuriensis. Our results indicate the presence of two Japanese haplotypes within the continental group, which is inconsistent with the assumed scenario of post-glacial expansion of raccoon dogs excluding gene flow between continental and Island populations.

Populations of Japanese macaques were significantly reduced in most areas from the 1900s to the 1960s and then recovered mainly in the northeastern part of Honshu. A drastic reduction in population size reduces genetic variability through a bottleneck effect. Demographic expansion after the reduction that accumulates new mutations can reduce the bottleneck effects or drive the recovery of genetic variability. We examined the genetic status of a small island population (Kinkazan Island) and a larger mainland population (southern Tohoku) of Japanese macaques that experienced recent demographic bottlenecks and recovery using eight microsatellite loci. The two populations were significantly genetically different from each other. The Kinkazan population exhibited lower genetic variability, remarkable evidence of bottleneck (i.e., significant heterozygosity excess and lower frequency of rare alleles), and a considerably smaller effective population size based on genetic data than based on the current census size. These results indicate that the genetic status has not completely recovered from the demographic bottleneck despite a full recovery in census size on Kinkazan Island. New mutations might rarely have accumulated because of the small carrying capacity of the island. Therefore, the genetic variability of the population would have been restrained by the severe bottleneck size, small carrying capacity, and long-term isolation. On the other hand, the bottleneck effect seems to be limited in the southern Tohoku population considering higher genetic variability, non-significant heterozygosity excess in many mutation conditions, and the highest frequency of rare alleles. [ABSTRACT FROM AUTHOR]

The raccoon dog (Nyctereutes procyonoides) is a representative of Canidae and is closely related to red fox-like canids, although the species exhibits high distinctiveness in the family. These animals were farmed for fur products, but thousands were intentionally released into the wild in western Russia. This newly established alien species in Europe has spread rapidly into many European countries. The aim of the study was to determine the origin of Polish populations by comparing the mitochondrial molecular marker cytochrome b (cytb) sequences of Polish wild and farm individuals with wild raccoon dogs from the western Russia and Asian specimens whose sequences were obtained from GenBank resources. The results of our phylogenetic analysis support the previous suggestions on the existence of two main clades clearly referring to continental and Island populations. Polish individuals were classified into a highly diverse continental group. The relationships between the haplotypes within the clade together with estimated values of genetic diversity parameters indicate that the Polish raccoon dog populations exhibit high genetic similarity to the Russian population. In combination with the history of introduction of the species to Europe, this suggests the most probable assignment of the Polish populations to the subspecies N. procyonoides ussuriensis. Our results indicate the presence of two Japanese haplotypes within the continental group, which is inconsistent with the assumed scenario of post-glacial expansion of raccoon dogs excluding gene flow between continental and Island populations. [ABSTRACT FROM AUTHOR]

Plant populations at the leading edge of the species’ native range often exhibit genetic structure as a result of genetic drift and adaptation to harsh environmental conditions. Hence, they are likely to harbour rare genetic adaptations to local environmental conditions and therefore are of particular interest to understand climate adaptation. We examined genetic structure of nine northern marginal mainland, peninsular and isolated island natural populations of northern red oak (Quercus rubraL.), a valuable long-lived North American hardwood tree species, covering a wide climatic range, using 17 nuclear microsatellites. We found pronounced genetic differentiation of a disjunct isolated island population from all mainland and peninsular populations. Furthermore, we observed remarkably strong fine-scale spatial genetic structure (SGS) in all investigated populations. Such high SGS values are uncommon and were previously solely observed in extreme range-edge marginal oak populations in one other study. We found a significant correlation between major climate parameters and SGS formation in northern range-edge red oak populations, with more pronounced SGS in colder and drier regions. Most likely, the harsh environment in leading edge populations influences the density of reproducing trees within the populations and therefore leads to restricted overlapping of seed shadows when compared to more central populations. Accordingly, SGS was negatively correlated with effective population size and increased with latitude of the population locations. The significant positive association between genetic distances and precipitation differences between populations may be indicative of isolation by adaptation in the observed range-edge populations. However, this association was not confirmed by a multiple regression analysis including geographic distances and precipitation distances, simultaneously. Our study provides new insights in the genetic structure of long-lived tree species at their leading distribution edge.

• Little is known of epilepsy care in small economically developed countries (pop:500 k) • This study is on clinical & risk features of adults with epilepsy (68) in Gozo, Malta. • 92% were compliant with their anti-seizure medication (ASM) with most on just one ASM. • 19% were on antipsychotics, 18% had an epilepsy care plan & none had SUDEP advice. • Stigma & shame play a significant role in small communities & access to care. People with epilepsy are at increased risk of multiple co-morbidities that may influence risk of adverse outcomes including impact on quality of life and premature mortality. These risk factors include potentially modifiable clinical characteristics associated with sudden unexpected death in epilepsy (SUDEP). For services to tackle risk, the clinical complexity of the target epilepsy population needs to be defined. While this has been comprehensively studied in large, economically developed countries little knowledge of these issues exist in small economically developed countries, like Malta (population: 500,000). This was a single centre study focused exclusively on patients attending Gozo General Hospital (GGH) Malta. STROBE guidance for reporting cross sectional studies was used to design and report the study. This was a retrospective review of standard care and SUDEP and seizure risks provided to all adults (over 18 years) with epilepsy attending GGH (2018–2021). The review identified 68 people and 92% were compliant with their anti-seizure medication. A fifth (21%) had an intellectual disability. Despite only one patient having a psychotic illness, 19% were on antipsychotic medication. Only 18% of patients had a specific epilepsy care plan, 6% nocturnal surveillance and none had received advice on SUDEP. Patient outcomes may be improved with increasing rates of personalized epilepsy care plans, appropriate nocturnal surveillance and reducing the prescription of antipsychotic medication as it is associated with greater risk of mortality. Issues such as stigma and shame appear to play a significant role in small communities and their access to care. [ABSTRACT FROM AUTHOR]

This article addresses the political practices of women and men who live in islands of the Paraná River Delta focusing on the daily practices of territorial resistance of these members of "islander" families in the defense of their right to inhabit this territory. These practices are organized according to the spaces and roles prescribed by the local gender regime. The essay analyses power relations between genders and the ways in which power is constructed, legitimated and circulated. [ABSTRACT FROM AUTHOR]

Fruit bats are important pollinators for plants and play important ecological functions and services in the tropical rain forest. Fruit bats are considered more important for the ecological rehabilitation and health of the plant community on islands as other pollinators may not be able to fly across open sea and reach the island. This study was conducted to determine the diversity of fruit bats in three contrasting Terengganu offshore islands, namely, Pulau Perhentian, Pulau Bidong, and Pulau Redang. A total of 40 individuals of four species were captured using 10 mist nets during the 180 mist-net night sampling period from June 27, 2019 until February 29, 2020. Pulau Bidong had the highest number of bats captured (22), followed by Pulau Redang (18) and Pulau Perhentian (0). The most frequently captured species was Cynopterus brachyotis in both islands. No yield in Pulau Perhentian may be caused by tourism activity, seasonal movement following flowering and fruiting trees, or inadequate sampling effort in multiple sites. The data can be further used to determine factors in assessing threats and for future conservation by the management authorities. [ABSTRACT FROM AUTHOR]

Individuals which have invaded urbanized environments are reported to engage in riskier behaviors, possibly influenced by the scarcity of predators in urbanized areas. Here, we studied the risk-taking behavior of birds which had invaded a new natural environment, rather than an artificial urban environment, using recently established populations of the bull-headed shrike Lanius bucephalus , which naturally colonized three subtropical islands in Japan. We compared flight initiation distance (FID), the distance at which an individual approached by a human initiates flight, between the islands and the temperate mainland. FID was longer for the insular shrikes compared with the mainland shrikes after controlling for other factors, indicating that the individuals which had invaded a new natural environment had a lower propensity for risk-taking. A possible explanation for these results is that low risk-taking behavior might be adaptive on the islands due to predation by the black rat Rattus rattus , an unfamiliar predator not found in shrike habitats on the temperate mainland. Further studies are needed to examine the nest predation rate, predator species, and nest site selection of these insular shrike populations. [ABSTRACT FROM AUTHOR]

Abstract Background The extent to which seasonal changes in food availability affect small-scale movements in free-ranging populations of birds of prey is relatively little studied. Here we describe a seasonal “micro-migration” of a farm-island population of striated caracaras (Phalcoboenus australis) in the Falkland Islands in response to seasonal changes in the availability of seabird carcasses. We banded more than 450 individuals on Saunders Island, deployed archival and satellite GPS data loggers on 17 individuals, and monitored movements within and between two feeding areas on Saunders Island, a “marine-subsidized” site near seabird colonies and an anthropogenic “human-subsidized” farm site 16 km to the southeast. Results During 67 observation days between 2010 and 2015, resightings of 312 banded caracaras were greater at the marine-subsidized site during austral summer than winter, and the total daily resightings varied significantly between spring versus summer, summer versus winter, autumn versus spring, and autumn versus winter. Resightings were higher at the human-subsidized site in austral winter than summer and the total daily resightings varied significantly across all bi-seasonal comparisons. Resightings indicated that at least 12 of 197 birds (6.1%) moved between the human- and marine-subsidized sites at least once during the same winter, 15 of 335 birds (4.5%) did so in spring, none of 164 birds did so in summer, and 16 of 297 birds (5.4%) did so in autumn. Individuals fitted with archival GPS data loggers at the marine-subsidized site in summer maintained highly localized 95% kernel core areas (0.55 ± 0.12 km2 [mean ± SD]), whereas those at the human-subsidized site in winter maintained larger 95% kernel core areas (3.8 ± 4.6 km2). Two of 6 satellite-tagged individuals that summered at known caracara breeding colonies 80 km WNW of Saunders Island were subsequently resighted in winter at the human-subsidized site. Conclusion Our results suggest that seasonal shifts in food resource availability drive seasonal micro-migrations in a farm-island population of striated caracaras, and that farm sites can be critical in providing nutritional resources for caracaras when naturally occurring marine-subsidized resources become less available. Our results have important implications for striated caracara spatial ecology and conservation, as increased winter survival could improve the status of this globally Near-Threatened population.

This study focuses on the taxonomic, evolutionary and conservation implications of a striking reduction in body size previously observed in an island population of gazelles by comparing the genetic structure of island and mainland populations. Mitochondrial sequence diversity of the mainland population was found to be comparable to that of other true gazelles of East Africa. We discuss this in the context of the prolonged armed conflict in our study region. In contrast, the gazelles on Dahlak Kebir, one of the over 200 islands and islets of the Dahlak archipelago on the Red Sea, were found to be genetically depauperate. Nucleotide and haplotype diversity estimates were a sixth and a third of that of the mainland population respectively. Using estimates of Tajima's D statistic, we inferred that the Dahlak population has undergone expansion after a recent bottleneck. A minimum spanning genealogical network of mitochondrial control region sequences produced testable hypotheses on the route and timing of the colonization of Dahlak Kebir by gazelles from the mainland. Our mitochondrial DNA dataset has resolved the taxonomic ambiguity of the island gazelles. Their genetic distinctiveness and, their striking conformity to the Island Rule that was highlighted in a previous study, are discussed from evolutionary and conservation perspectives. [ABSTRACT FROM AUTHOR]

The endangered crocodile newt, Echinotriton andersoni, is a relatively large species of the family Salamandridae and is distributed on six islands in the central part of the Ryukyu Archipelago, Japan. Because of an originally small distribution range and recent habitat loss, this species has been steadily declining in number. To elucidate fine-scale population structure, which is essential for effective conservation management, we analyzed genetic diversity and gene flow based on nine microsatellite loci. Our results identified three different island groups (Amamioshima, Tokunoshima, and Okinawajima) and multiple genetic assemblages within the Amami and Okinawa island groups. The gross genetic variation within each island was positively correlated with island size. Population structure followed a latitudinal cline and isolation by distance, even among geographically isolated islands. In northern Okinawajima, relatively complex genetic structure was observed. This unexpected population structure seems to reflect historical migration and distribution expansion through the formation of land bridges and shifted coastlines in the Pleistocene. We also found that small islands showed little genetic variation (Ukeshima, Sesokojima, and Tokashikijima). In particular, our findings revealed that the Tokashikijima population is at greater risk for extinction than the other populations because it has the smallest effective population size. [ABSTRACT FROM AUTHOR]

Inbreeding depression, though challenging to identify in nature, may play an important role in regulating the dynamics of small and isolated populations. Conversely, greater expression of genetic load can enhance opportunities for natural selection. Conditional expression concentrates these opportunities for selection and may lead to failure of detection. This study investigates the possibility for age-dependent expression of inbreeding depression in a critically endangered population of rock iguanas, Cyclura nubila caymanensis. We employ heterozygote-fitness correlations to examine the contributions of individual genetic factors to body size, a fitness-related trait. Nonsignificant reductions in homozygosity (up to 7%) were detected between neonates and individuals surviving past their first year, which may reflect natural absorption of inbreeding effects by this small, fecund population. The majority of variation in neonate body size was attributed to maternal or environmental effects (i.e. clutch identity and incubation length); however, heterozygosity across 22 microsatellite loci also contributed significantly and positively to model predictions. Conversely, effects of heterozygosity on fitness were not detectable when adults were examined, suggesting that inbreeding depression in body size may be age dependent in this taxon. Overall, these findings emphasize the importance of taking holistic, cross-generational approaches to genetic monitoring of endangered populations. [ABSTRACT FROM AUTHOR]

In natural populations susceptible to inbreeding depression, behaviors such as female promiscuity and disassortative mating may enhance the production of outbred progeny and help maintain genetic variation at the population-level. However, empirical tests of such hypotheses have largely focused on mating systems in which female choice is known to play a large role. In insular reptile populations, cryptic choice may be important for overcoming constraints on precopulatory choice and diversifying breeder representation. We carried out pedigree reconstructions of 50 clutches of critically endangered Cyclura nubila caymanensis (Sauria: Iguanidae) to investigate the prevalence and efficacy of strategies theorized to optimize genetic compatibility among mate pairs. We found that females mating disassortatively and multiply, but not with respect to male heterozygosity, tended to produce more heterozygous offspring on average. Pair relatedness also had a negative effect on hatching success, whereas additional sires positively influenced clutch size. Despite evidence for direct and indirect benefits, females did not mate with more outbred or genetically dissimilar males than expected by chance. Our data imply strong reproductive skew among males, with geographic proximity and body size largely predicting siring success. Multiple-paternity occurred in a minimum of 38% of clutches. Paradoxically, females were not more promiscuous when confronted with more males, as demonstrated at a site supporting high local densities. Our data imply that while female-mating behaviors have the potential to confer adaptive benefits in this small population, the trajectory of mating system evolution may be largely constrained by sexual conflict. [ABSTRACT FROM AUTHOR]

Abstract: Eighty‐two complete and partial human skeletons were excavated from a burial site on the island of Borkum in the North Sea. The site covers a period of 400 years from the middle of the 14th century AD until 1720 AD. The position of the skeletons in situ suggests rapid disposal of the bodies. About 75% of the skeletons were male and of a quite robust constitution, and about 60% of all individuals died rather young between 20 and 40 years of age. All male skeletons exhibited particular pathological alterations as a result of the typical daily activities of seafaring men, including severe degenerative joint disease and pronounced osteochondropathies. In juvenile skeletons, these pathologies were accompanied by inflammatory processes without exception. Palaeodietary reconstruction by stable isotope analysis resulted in a protein rich diet, confirming fishing as an important part of the subsistence economy. The juveniles derived substantially more protein from plant food than the adults. Bone collagen amino acid profiles were short of hydroxylysine, suggesting that the conspicuous pathological lesions could also have been caused by a systemic connective tissue disease. Possible etiology of the disease is discussed and related to both the uneven sex ratio of the inhumations and the burial context. [ABSTRACT FROM AUTHOR]

In Galicia (NW of the Iberian Peninsula) there is an important population of coastal Eurasian otters (Lutra lutra), some of which are present on islands. This study analyses the recent historical evolution of the species distribution along the Galician Atlantic Islands Maritime-Terrestrial National Park. National surveys of years 1984, 1994 and 2005, other local surveys conducted between 2000 and 2017, some publications and other technical reports have been used for this purpose. Also, between 2010 and 2017, the number of otters inhabiting each island and their relative age were estimated using camera traps. According to the information collected, otters may have disappeared or become very scarce in the last third of the 20th century. However, from the beginning of the 21st century, their populations began to recover, occupying today all the islands and the closest coasts. It has been confirmed otter breeding in all islands between 2010 and 2017. The average size of the observed litters was 1.89 cubs. There does not seem to be a welldefined breeding season pattern. For each of the islands, a minimum population of 4 otters was recorded. [ABSTRACT FROM AUTHOR]

The goal of this research was to analyze the reasons for absenteeism and school retention of the children of Riverine that harvest açaí fruit (Euterpe oleracea Mart.) on Combu Island, City of Belém - PA, Brazil and to suggest ways to minimize these problems in the island’s primary schools. It was found that the harvesting of açaí is not the only cause of school dropout but also scholastic curriculum guidelines that are geared towards an urban reality, disconnected from the economic reality of the students' families.

Sinomicrurus japonicus has a conspicuous colour pattern of longitudinal black stripes and transverse sets of black and white bands with an orange-reddish background colour. The pattern varies markedly among island populations, and thus, three subspecies have been recognized. We conducted molecular phylogenetic analyses on the island populations to clarify the evolutionary trajectory of such colour patterns and reevaluate the current classification accordingly. The results indicated relatively deep allopatric divergences within S. j. boettgeri, paraphyly of S. j. boettgeri against other two subspecies, and two independent derivations of S. j. takarai from boettgeri-like ancestors. Detailed morphological analyses revealed that variations in the boettgeri and takarai forms were more or less continuous and that differences between the two takarai populations were very small. From these results, we propose synonymizing S. j. takarai with S. j. boettgeri. Morphological differences between the genetically most distant populations of S. j. boettgeri were also small, whereas the japonicus form was distinct from the remainder. Considering the possible evolution of S. j. japonicus through peripheral isolation, we propose retention of these two subspecies. This study provides a basis for future work on the adaptive significance of geographic variation in the colour pattern of S. japonicus. [ABSTRACT FROM AUTHOR]

Increased human activities caused the isolation of populations in many species—often associated with genetic depletion and negative fitness effects. The effects of isolation are predicted by theory, but long-term data from natural populations are scarce. We show, with full genome sequences, that common voles (Microtus arvalis) in the Orkney archipelago have remained genetically isolated from conspecifics in continental Europe since their introduction by humans over 5,000 years ago. Modern Orkney vole populations are genetically highly differentiated from continental conspecifics as a result of genetic drift processes. Colonization likely started on the biggest Orkney island and vole populations on smaller islands were gradually split off, without signs of secondary admixture. Despite having large modern population sizes, Orkney voles are genetically depauperate and successive introductions to smaller islands resulted in further reduction of genetic diversity. We detected high levels of fixation of predicted deleterious variation compared with continental populations, particularly on smaller islands, yet the fitness effects realized in nature are unknown. Simulations showed that predominantly mildly deleterious mutations were fixed in populations, while highly deleterious mutations were purged early in the history of the Orkney population. Relaxation of selection overall due to benign environmental conditions on the islands and the effects of soft selection may have contributed to the repeated, successful establishment of Orkney voles despite potential fitness loss. Furthermore, the specific life history of these small mammals, resulting in relatively large population sizes, has probably been important for their long-term persistence in full isolation. [Display omitted] • Common voles on Orkney remained completely isolated for more than 5,000 years • Genetic drift led to a strong reduction of genetic diversity and population divergence • Orkney voles have high levels of detrimental mutations, especially on small islands • Simulations suggest purging of highly deleterious alleles, while mild ones persisted Wang et al. show that common voles on the Orkney archipelago have remained genetically isolated for more than 5,000 years after human introduction. Orkney voles lost most genetic diversity and harbor high levels of inferred strongly deleterious mutations, yet simulations and large current population sizes suggest rather mild effects on fitness. [ABSTRACT FROM AUTHOR]

This study investigates the genetic development of the German Krofdorfer Forst red deer population, located in the federal state of Hesse, by genotyping red deer hunted between 1960 and 1984 ('ancient' population) and between 2002 and 2012 ('extant' population). Krofdorfer Forst belongs to the smaller red deer areas in Hesse, with a census size in spring of 200 animals and is surrounded by areas designated as free of red deer. Because of this 'island' position, it should be evaluated whether there was a significant decrease in genetic diversity over time. DNA extracted from bone shavings of antlers and skulls was genotyped with 16 unlinked microsatellites. In the 'ancient' population, 131 alleles were detected, from which 39 were private alleles which disappeared from the 'extant' population over time. On the other hand, the 'extant' population had 112 alleles, from which 20 were new alleles acquired between 1984 and 2012. This means a net loss of 19 alleles over time in the 'extant' population. Despite this decrease in genetic diversity, there was a high number of effective alleles as compared to red deer populations in Bavaria. Furthermore, the low F value of 0.032 indicates low (or no) inbreeding and thus a likewise extremely low probability of deleterious alleles to become fixed. Using demographic data obtained from the red deer association of the Krofdorfer Forst, the effective population size was calculated to be 73, which reflects an increase in inbreeding of only 0.7 % per generation which confirms the low F value. [ABSTRACT FROM AUTHOR]

Wild boar is the most important large game species in Croatia, with populations subjected to hunting/management programs. There are indications from previous analyses of morphological variation and reproductive performance that population structure of wild boar in Croatia is strongly influenced by the Dinaric mountain range that separates Croatia in two biogeographic regions: Continental and Mediterranean. Of the two main wild boar haplogroups found in Europe, the most widespread is the E1 clade (present from Portugal to Russia), while the E2 clade is found within the Italian peninsula and on Sardinia. Outside Italy, the E2 clade has to date been found only in archaeological samples from the Mediterranean region of Croatia. The aims of this study were to investigate the hypotheses that (i) the Dinaric Mountains act as a natural boundary separating the Continental and Mediterranean wild boar subpopulations in Croatia; and (ii) the mtDNA E2 clade is present in Croatian wild boar. A total of 14 unlinked microsatellite loci were examined in 264 geo-referenced individuals, and the 486-bp fragment of the mtDNA control region sequence was examined in 69 individuals. The results suggest that the region of the Dinaric Mountains. represents a weak boundary between the Continental and Mediterranean subpopulations, and that the predominant factor causing the observed genetic structuring is isolation by distance. Based on these results, it can be proposed that the Croatian wild boar population in the mainland should be managed as a whole. Three variable sites and four haplotypes were obtained from the mtDNA sequences, all of which belonged to the major European clade (E1). [ABSTRACT FROM AUTHOR]

The movement patterns and demographic parameters were measured for caribou (Rangifer tarandus caribou) on George’s Island (Labrador, Canada) to determine if the population is separate from the Mealy Mountain Caribou Herd. Movements between George’s Island caribou and nearby Mealy Mountain caribou were examined through satellite telemetry (April 2005 to April 2006). Demographic information was collected through aerial classification surveys. The predator-free island is currently maintaining a density of 22.5-26.5 caribou/km2. Female survival appears high and the recruitment rate in late fall-early spring was 19.0-29.2% calves. Mainland caribou moved very little throughout the year, travelling no more than 53.7 km on average from their initial collaring locations. Also, satellite data indicated no mixing between animals on George’s Island and the mainland. The elevated caribou density and high proportion of calves suggest that George’s Island could at times be acting as a predator-free recruitment area and that George’s Island may be a subpopulation from which animals disperse to the mainland.

The article discusses a study which investigated the origin of three red-crowned Crane Grus japonensis in Northeast Honshu and west Hokkaido, Japan from 2008 to 2012. Two (Gj1 and Gj2) haplotypes in D-loop of mtDNA were identified in Japan, and seven (Gj3-Gj9) haplotypes were found in the continent. Meanwhile, a crane in Akita was found to have a novel haplotype (Gj10).

Considerable technological advances have been made towards the generation of genetically modified mosquitoes for vector control. In contrast, less progress has been made towards field evaluations of transformed mosquitoes which are critical for evaluating the success of, and hazards associated with, genetic modification. Oceanic islands have been highlighted as potentially the best locations for such trials. However, population genetic studies are necessary to verify isolation. Here, we used a panel of genetic markers to assess for evidence of genetic isolation of two oceanic island populations of the African malaria vector, Anopheles gambiae s.s. We found no evidence of isolation between the Bijag os archipelago and mainland Guinea-Bissau, despite separation by distances beyond the known dispersal capabilities of this taxon. Conversely, the Comoros Islands appear to be genetically isolated from the East African mainland, and thus represent a location worthy of further investigation for field trials. Based on assessments of gene flow within and between the Comoros islands, the island of Grande Comore was found to be genetically isolated from adjacent islands and also exhibited local population structure, indicating that it may be the most suitable site for trials with existing genetic modification technologies. [ABSTRACT FROM AUTHOR]

Bird songs in island populations have often been reported to be simplified, in that island birds have a smaller number of song types and song-element types compared to mainland birds. However, there is less information on the characteristics of acoustic structure in island songs. I investigated song structure of one mainland and three island populations of Japanese bush warblers, Cettia diphone, and found that island songs had an acoustically simple structure. The frequency-modulated (FM) portions of the songs were shorter and had fewer frequency inflections in the insular populations than in the mainland population, while the number of FM notes, the frequency range of these notes, and the song repertoire sizes of males did not differ between the islands and the mainland. I also investigated whether the song complexity is related to sexual selection pressure using the degree of sexual size dimorphism as a proxy for the latter. The degree of dimorphism in body mass was larger on the mainland. Thus, weakened sexual selection on islands is a possible factor in the formation of simple songs. Further studies related to male-male competition and female choice on islands are required. [ABSTRACT FROM AUTHOR]

Understanding how fitness is related to genetic variation is of crucial importance in both evolutionary ecology and conservation biology. We report a study of heterozygosity-fitness correlations in a wild, noninbred population of Zenaida Doves, Zenaida aurita, based on a sample comprising 489 individuals (382 adults and 107 juveniles) typed at 13 microsatellite loci, resulting in a data set comprising 5793 genotypes. In both adults and juveniles, and irrespective of sex, no evidence was found for an effect of either multilocus or single-locus heterozygosity on traits potentially related to fitness such as foraging tactic, competitive ability, and fluctuating asymmetry. In contrast, a significant negative correlation between body condition and multilocus heterozygosity, indicative of outbreeding depression, was found in juveniles, whereas no such trend was observed in adults. However, the frequency distribution of heterozygosity did not differ between the two age classes, suggesting compensatory growth by heterozygous juveniles. We discuss our results in relation to some practical limitations associated with studies of heterozygosity-fitness correlations, and suggest that tropical bird species with allopatric divergence between island populations may provide a good biological model for the detection of outbreeding depression. [ABSTRACT FROM PUBLISHER]

Common Terns nesting at Bermuda are isolated by 1,000-4,000 km from other populations of the species around the North Atlantic Ocean. This population experienced a severe demographic bottleneck as a result of a hurricane in 2003 and was subsequently re-established by four males and four females. Using seven microsatellite loci, we compared the genetic diversity of the pre- and post-bottleneck populations, compared the genetic profile of the Bermuda population with those of other populations around the North Atlantic Ocean and mainland Europe, and assessed the potential contribution of immigration to genetic diversity. We found a loss of genetic diversity (number of alleles and heterozygosity) in the post-bottleneck Bermudian population (4.6-2.9 and 0.56-0.52, respectively). We also report significant differentiation among all sampled locations (global F = 0.16) with no evidence for immigration into Bermuda. Common Terns from the Azores were genetically more similar to those from mainland North America than to those from Bermuda or mainland Europe. Our results suggest that the critically endangered population in Bermuda is genetically distinct and requires continued and enhanced conservation priority. [ABSTRACT FROM AUTHOR]

Isolated populations of a given species may diverge from conspecifics for a certain series of traits. It is of particular interest when this divergence involves the signals and the related responses used by sexually reproducing animals to identify prospective mating partners. Using behavioural trials during reproductive season, we studied pheromone-mediated response between insular and mainland European whip snakes, Hierophis viridiflavus. Our results revealed that both insular and mainland males can utilise both homotypic and heterotypic chemical cues. However, while insular snakes did not show any preference between the two types of chemical cues, mainland males preferred homotypic odours. These results, though preliminarly, show the existence of asymmetry in the displayed behavioural patterns and support the idea that isolated populations may evolve differences in communication systems. [ABSTRACT FROM AUTHOR]

Habitat fragmentation can act to cause reproductive isolation between conspecifics and undermine species' persistence, though most studies have reported the genetic condition of populations that have already declined to a very small size. We examined genetic diversity within the vulnerable, declining koala ( Phascolarctos cinereus) population in Southeast Queensland, Australia to determine the genetic impact of ongoing threatening processes. Five hundred and twelve koalas from ten Southeast Queensland Local Government Areas on the mainland and one island were genotyped at six polymorphic microsatellite loci. Based on Bayesian cluster analysis incorporating spatial data, the regional koala population was subdivided into six clusters, with location of major roads and rivers appearing to be consistent with being barriers to gene flow. The distribution of mtDNA control region haplotypes identified distinct coastal and inland clades suggesting that historically there was gene flow between koalas along the coast (though little interchange between coastal and inland animals). In contrast, koalas from the Koala Coast (Brisbane City, Logan City and Redland Shire) were shown by microsatellite analysis to be genetically distinct from adjacent areas. It is likely, therefore, that more recent reductions in population size and restricted gene flow through urbanisation have contributed to the genetic differentiation of koalas in the Koala Coast region. [ABSTRACT FROM AUTHOR]