Non-migratory Population Research Articles

Conservation risks and benefits of establishing monarch butterfly (Danaus plexippus) breeding habitats close to maize and soybean fields in the north central United States: A landscape-scale analysis of the impact of foliar insecticide on nonmigratory monarch butterfly populations.

Establishing habitat in agricultural landscapes of the north central United States is critical to reversing the decline of North America's eastern monarch butterfly (Danaus plexippus) population. Insecticide use could create population sinks and threaten recovery. Discouraging habitat establishment within a 38-m zone around crop fields is a suggested risk mitigation measure. In Story County, Iowa, United States, this mitigation would discourage habitat establishment in 84% of roadsides and 38% of noncrop land. It is unclear if the conservation benefits from establishing habitat close to crop fields outweigh suppression of population growth owing to insecticide exposure. Consequently, monarch conservation plans require spatially and temporally explicit landscape-scale assessments. Using an agent-based model that incorporates female monarch movement and egg laying, the number and location of eggs laid in Story County were simulated for four habitat scenarios: current condition, maximum new establishment, moderate establishment, and moderate establishment only outside a 38-m no-plant zone around crop fields. A demographic model incorporated mortality from natural causes and insecticide exposure to simulate adult monarch production over 10 years. Assuming no insecticide exposure, simulated adult production increased 24.7% and 9.3%, respectively, with maximum and moderate habitat establishment and no planting restrictions. A 3.5% increase was simulated assuming moderate habitat establishment with a 38-m planting restriction. Impacts on adult production were simulated for six representative insecticides registered for soybean aphid (Aphis glycines) management. Depending on the frequency of insecticide applications over a 10-year period, simulated production increased 8.2%-9.3%, assuming moderate habitat establishment with no planting restrictions. Results suggest that the benefits of establishing habitat close to crop fields outweigh the adverse effects of insecticide spray drift; that is, metapopulation extirpation is not a concern for monarchs. These findings are only applicable to species that move at spatial scales greater than the scale of potential spray-drift impacts. Integr Environ Assess Manag 2021;17:989-1002. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Spatial variation in antler investment of Apennine red deer.

Heterogeneity in resource availability and quality can trigger spatial patterns in the expression of sexually selected traits such as body mass and weaponry. While relationships between habitat features and phenotypic quality are well established at broad geographical scales, information is poor on spatial patterns at finer, intrapopulation scales. We analyzed biometric data collected on 1965 red deer Cervus elaphus males over 20 years from a nonmigratory population living on two sides of a mountainous ridge, with substantial differences in land cover and habitat quality but similar climate and population density. We investigate spatial patterns in (i) body mass, (ii) antler mass, and (iii) antler investment. We also tested for site‐ and age‐specific patterns in allometric relationship between body mass and antler mass. Statistically significant fine‐scale spatial variations in body mass, antler mass, and, to a lesser extent, antler allocation matched spatial differences in land cover. All three traits were greater in the northern slope, characterized by higher habitat heterogeneity and greater availability of open habitats, than in the southern slope. Moreover, the allometric relationship between body mass and antler mass differed among age‐classes, in a pattern that was consistent between the two mountain slopes. Our results support the occurrence of spatial patterns in the expression of individual attributes also at a fine, intrapopulation scale. Our findings emphasize the role of environmental heterogeneity in shaping spatial variations of key life‐history traits, with potential consequences for reproductive success.

Conservation and improvement of Kankrej cattle (Bos indicus): Status vis-Ã -vis strategies

The present study was conducted at Livestock Research Station, to compare performance of Kankrej cattle at farm and field condition, and to suggest strategies for the overall improvement of this prestigious breed. The average lactation yield (lit.), standard lactation (lit.), fat percentage, age at first calving and calving interval in the farmers herd was 1669.96±12.24 (1523), 1751.23±12.94 (617), 4.13±0.03 (617), 1464.08±18.41 (260) and 549.93±8.61 (387), respectively during the initial phage of progeny testing program initiated by station and the performance of migratory herd was 2.64 litre (wet average). While, the average lactation yield (lit.), standard lactation (lit.), fat percentage, age at first calving and calving interval at station was 2682.27±126.71 (59), 2501.15±87.72 (59), 4.08±0.09 (49), 1218.42±35.27 (12) and 435.73±13.94 (36), respectively (Elite herd, Anonymous 2018). The lactation yield of daughters born under the progeny testing program was 2050.29±119.20 (104) litres. Looking to the performance gap between the herd maintained at station, field and pastoralist indicates wide scope for the genetic improvement in Kankrej breed by following strict breeding strategies which are discussed in this paper. Conclusively, intensive selective breeding with the use of artificial insemination technology at large scale and progeny testing with precise recording at small scale will solve the purpose in the non-migratory population while, supply of high genetic merit male calf or proven bull’s male calf to the Maldharis having migratory population.

Breeding biology in a population of Rufous-collared Sparrow (Zonotrichia capensis, Statius Müller, 1776) at different elevations in the Tropical Andes

Abstract: Breeding biology in a population of Rufous-collared Sparrow (Zonotrichia capensis, Statius Müller, 1776) at different elevations in the Tropical Andes. Elevation strongly influences the evolution of life history traits associated with bird physiology and reproduction. Since life history traits in birds are modulated by environmental factors that vary with elevation, we expected to find changes in breeding biology traits of Z. capensis at different elevations. In this study, we compared the breeding biology (clutch size, egg volume, and reproductive activity) of a non-migratory population of Z. capensis in two localities at different elevations (low and high elevations, 1 800 m a.s.l., and 3 800 m a.s.l., respectively) and same latitude in the Colombian Tropical Andes for a one-year period. We found no differences in clutch size between the localities; however, egg volume was higher at high elevation. Furthermore, the reproductive activity differed significantly between localities. We propose that clutch size is likely conserved throughout the altitudinal distribution of Z. capensis since the species evolved in Tropical lowlands. On the other hand, the larger egg volume at high elevation could obey local environmental factors that may favor the reproductive success of the population.

Strontium Uptake and Intra-Population 87Sr/86Sr Variability of Bones and Teeth—Controlled Feeding Experiments With Rodents (Rattus norvegicus, Cavia porcellus)

Strontium isotopes in biogenic apatite, especially enamel, are widely employed to determine provenance and track migration in palaeontology and archaeology. Body tissues record the 87Sr/86Sr of bioavailable Sr of ingested food and water. To identify non-local individuals, knowledge of the 87Sr/86Sr of a non-migratory population is required. However, varying factors such as tissue turnover rates, feeding selectivity, Sr content, digestibility of food, and the ingestion of mineral dust can influence body tissue 87Sr/86Sr. To evaluate the Sr contribution of diet and water to mammalian hard tissues 87Sr/86Sr, controlled feeding studies are necessary. Here we present 87Sr/86Sr from controlled feeding experiments with two rodent species (Rattus norvegicus, Cavia porcellus). Due to the continuous and fast incremental growth of rat and guinea pig incisors (~0.1 – 0.5 mm/day), their enamel is expected to record isotopic dietary changes. For Experiment-1: Diet Switch, animals were switched from their respective supplier food to a pelleted experimental diet containing either insect-, plant-, or meat-meal and a staggered-sampling approach was used to monitor the 87Sr/86Sr changes in rat incisor enamel and bone over the course of the experiment. In Experiment-2: Basic Diets, separated cohorts (n = 6) of rats and guinea pigs were fed one of the three pelleted diets and received tap water for 54 days. While the rat incisors showed a complete tissue turnover, the slower-growing guinea pig incisors partially retained supplier diet-related isotopic compositions. In addition, one group of rats fed plant-meal pellets received Sr-rich mineral water, demonstrating that drinking water can be an important Sr source in addition to diet. Additionally, a leaching experiment showed that only a small fraction of diet-related Sr is bioavailable. Finally, in Experiment-3: Dust Addition, guinea pigs were fed pellets with and without addition of 4% of isotopically distinct dust (loess or kaolin). Animals that received kaolin-containing pellets displayed increased enamel 87Sr/86Sr. Intra-population 87Sr/86Sr variability within each feeding group was small and thus we conclude that it should not affect interpretations of 87Sr/86Sr in provenance studies. However, the differences between bulk food and leachate 87Sr/86Sr highlight the importance of Sr bioavailability for provenance studies and Sr isoscapes.

Investigating Diadromy in Fishes and Its Loss in an -Omics Era.

SummaryDiadromy, the predictable movements of individuals between marine and freshwater environments, is biogeographically and phylogenetically widespread across fishes. Thus, despite the high energetic and potential fitness costs involved in moving between distinct environments, diadromy appears to be an effective life history strategy. Yet, the origin and molecular mechanisms that underpin this migratory behavior are not fully understood. In this review, we aim first to summarize what is known about diadromy in fishes; this includes the phylogenetic relationship among diadromous species, a description of the main hypotheses regarding its origin, and a discussion of the presence of non-migratory populations within diadromous species. Second, we discuss how recent research based on -omics approaches (chiefly genomics, transcriptomics, and epigenomics) is beginning to provide answers to questions on the genetic bases and origin(s) of diadromy. Finally, we suggest future directions for -omics research that can help tackle questions on the evolution of diadromy.

Genomic basis of the loss of diadromy in Galaxias maculatus: Insights from reciprocal transplant experiments

Diadromy is known for having major effects on the distribution and richness of aquatic species, and so does its loss. The loss of diadromy has led to the diversification of many species, yet research focusing on understanding its molecular basis and consequences are limited. This is particularly true for amphidromous species despite being the most abundant group of diadromous species. Galaxias maculatus, an amphidromous species and one of the most widely distributed fishes in the Southern Hemisphere, exhibits many instances of nonmigratory or resident populations. The existence of naturally replicated resident populations in Patagonia can serve as an ideal system for the study of the mechanisms that lead to the loss of the diadromy and its ecological and evolutionary consequences. Here, we studied two adjacent river systems in which resident populations are genetically differentiated yet derived from the same diadromous population. By combining a reciprocal transplant experiment with genomic data, we showed that the two resident populations followed different evolutionary pathways by exhibiting a differential response in their capacity to survive in salt water. While one resident population was able to survive salt water, the other was not. Genomic analyses provided insights into the genes that distinguished (a) migratory from nonmigratory populations; (b) populations that can vs those that cannot survive a saltwater environment; and (c) between these resident populations. This study demonstrates that the loss of diadromy can be achieved by different pathways and that environmental (selection) and random (genetic drift) forces shape this dynamic evolutionary process.

Winter movement patterns of a globally endangered avian scavenger in south-western Europe

Partial migration, whereby some individuals migrate and some do not, is relatively common and widespread among animals. Switching between migration tactics (from migratory to resident or vice versa) occurs at individual and population levels. Here, we describe for the first time the movement ecology of the largest wintering population of Egyptian Vultures (Neophron percnopterus) in south-west Europe. We combined field surveys and GPS tracking data from December to February during four wintering seasons (2014–2018). The wintering population consisted on average of 85 individuals (range 58–121; 76% adults and 24% subadults). Individuals were counted at five different roosting sites located near farms, unauthorized carcass deposition sites and authorized carcass deposition sites. Our results show that vultures tend to remain close to the roosting site. Moreover, we observed that females exhibited smaller home range sizes than males, which suggests a possible differential use of food sources. Overall, birds relied more on farms than other available food resources, particularly subadult individuals which exploited more intensively these sites. Our results showed that Egyptian Vultures congregate in significant numbers at specific sites throughout the winter period in south-west Spain and that these roosting and feeding sites should be given some level of legal protection and regular monitoring. Furthermore, predictable food sources might be driving the apparent increase in the non-migratory population of Egyptian Vultures, as observed in other avian species which are also changing their migratory behavior.

Agriculture creates subtle genetic structure among migratory and nonmigratory populations of burrowing owls throughout North America.

Population structure across a species distribution primarily reflects historical, ecological, and evolutionary processes. However, large‐scale contemporaneous changes in land use have the potential to create changes in habitat quality and thereby cause changes in gene flow, population structure, and distributions. As such, land‐use changes in one portion of a species range may explain declines in other portions of their range. For example, many burrowing owl populations have declined or become extirpated near the northern edge of the species' breeding distribution during the second half of the 20th century. In the same period, large extensions of thornscrub were converted to irrigated agriculture in northwestern Mexico. These irrigated areas may now support the highest densities of burrowing owls in North America. We tested the hypothesis that burrowing owls that colonized this recently created owl habitat in northwestern Mexico originated from declining migratory populations from the northern portion of the species' range (migration‐driven breeding dispersal whereby long‐distance migrants from Canada and the United States became year‐round residents in the newly created irrigated agriculture areas in Mexico). We used 10 novel microsatellite markers to genotype 1,560 owls from 36 study locations in Canada, Mexico, and the United States. We found that burrowing owl populations are practically panmictic throughout the entire North American breeding range. However, an analysis of molecular variance provided some evidence that burrowing owl populations in northwestern Mexico and Canada together are more genetically differentiated from the rest of the populations in the breeding range, lending some support to our migration‐driven breeding dispersal hypothesis. We found evidence of subtle genetic differentiation associated with irrigated agricultural areas in southern Sonora and Sinaloa in northwestern Mexico. Our results suggest that land use can produce location‐specific population dynamics leading to subtle genetic structure even in the absence of dispersal barriers.

Alternative Life-History in Native Trout (Salmo spp.) Suppresses the Invasive Effect of Alien Trout Strains Introduced Into Streams in the Western Part of the Balkans

Diversity of native trout fish Salmo spp. comprises a variety of nominal taxa in Serbia, Montenegro and Bosnia and Herzegovina. Recent mapping of the resident trout detected brown trout S. trutta (sensu stricto) of the Atlantic (AT) mtDNA lineage introduced into populations of both tentative Danubian trout S. labrax and of tentative Adriatic trout S. farioides belonging to the Danubian (DA) and Adriatic (AD) mtDNA lineages, respectively. In addition, an introduction of the tentative Macedonian trout S. macedonicus of the AD lineage was detected in the one native population of the tentative S. labrax. In almost all recipient non-migratory trout populations, a cross breeding between the native and introduced trout was detected by heterozygosity in either only LDH-C nuclear locus, or in LDH-C and particular microsatellites’ loci. Exception is one population where both resident and migratory, lake-dwelling individuals of the tentative Adriatic trout spawned at the downstream section of a stream in Montenegro, none of microsatellites’ alleles of Atlantic brown trout that were introduced into the upstream section was detected. The occurrence of cross breeding between Adriatic and brown trout was evident in the upstream, isolated section. It seems that migrating, lake-dwelling Adriatic trout in combination with their resident, stream-dwelling conspecifics suppress introgression of genes from those situated upstream, strongly introgressed by brown trout. Having this in sight, it is noteworthy to warn on the occurrence of the migratory brown trout in the Danube River at the broader Iron Gate Gorge area. They were recorded to migrate in late summer and early fall from the Iron Gate One reservoir to the lower sections of tributaries devoid of any trout fish. However, some of those streams home very special native trout of the DA lineage in their short-extending upper sections. Those native trout populations are so far still out of contact with the reservoir-dwelling trout. However, having in mind the resilience of trout featuring the migratory life-history, the outcome of this introduction could be deleterious for those natives very precious in conservational sense.

Timing of arrival in the breeding area is repeatable and affects reproductive success in a non-migratory population of blue tits.

Events in one part of the annual cycle often affect the performance (and subsequently fitness) of individuals later in the season (carry-over effects). An important aspect of this relates to the timing of activities. For example, many studies on migratory birds have shown that relatively late-spring arrival in the breeding area reduces both the likelihood of getting a mate or territory and reproductive success. In contrast, relatively little is known about the movements of individuals in non-migratory populations during the non-breeding season. Few studies have investigated the timing of arrival at the breeding area in such species, possibly due to the assumption that most individuals remain in the area during the non-breeding season. In this study, we used 4years of data from a transponder-based automated recording system set up in a non-migratory population of blue tits Cyanistes caeruleus to describe individual variation in arrival at the breeding site. We investigated whether this variation can be explained by individual characteristics (sex, body size or status), and we assessed its effect on aspects of reproductive success in the subsequent breeding season. We found substantial variation in arrival date and demonstrate that this trait is individual-specific (repeatable). Females arrived later than males, but the arrival dates of social pair members were more similar than expected by chance, which suggests that individuals may mate assortatively depending on their arrival in the breeding area. Arrival predicted both whether an individual would end up breeding that season and several aspects of its breeding success. Our study suggests that individuals of non-migratory species leave the breeding area during the non-breeding season. Hence, it may be useful to consider variation in the scale of movements between breeding and non-breeding sites, rather than using a simple dichotomy between 'resident' and 'migratory' species. We conclude that the timing of pre-breeding events, in particular arrival date, may be an overlooked, but important, fitness-relevant trait in non-migratory species.

Host plant adaptation during contemporary range expansion in the monarch butterfly.

Herbivores that have recently expanded their host plant ranges provide opportunities to test hypotheses about the evolution of host plant specialization. Here, we take advantage of the contemporary global range expansion of the monarch butterfly (Danaus plexippus) and conduct a reciprocal rearing experiment involving monarch populations with divergent host plant assemblages. Specifically, we ask the following questions: (1) Do geographically disparate populations of monarch butterflies show evidence for local adaptation to their host plants? If so, what processes contribute to this pattern? (2) How is dietary breadth related to performance across multiple host species in monarch populations? (3) Does the coefficient of variation in performance vary across sympatric versus allopatric hosts? We find evidence for local adaptation in larval growth rate and survival based on sympatric/allopatric contrasts. Migratory North American monarchs, which have comparatively broad host breadth, have higher mean performance than derived nonmigratory populations across all host plant species. Monarchs reared on their sympatric host plants show lower coefficient of variation in performance than monarchs reared on allopatric hosts. We focus our discussion on possible mechanisms contributing to local adaptation to novel host plants and potential explanations for the reduction in performance that we observed in derived monarch populations.

Attractiveness Assessment of the American Labour Market for the High Qualified Specialists: A Case of Doctors

The article describes the migration of highly qualified specialists, using the case of medical workers in the United States. The theory of Kurt Levin and its later modifications, that explain the attractiveness of certain labor markets for workers, serve as a theoretical basis. The study aims at examining a separate area and the reasons for its attractiveness to foreign labor, as well as assessing the prospects for the inflow or outflow of human capital in the medical industry. The American case is of a special research interest due to the national peculiarities of educational programs for medical workers in particular - the duration and the need of confirmation the qualifications by passing the so called qualification exams. The national system of selecting medical personnel for vacant positions throughout the country is also of interest, as it provides for an element of quotas (allocation of a certain number of jobs for foreign labor) and an element of competitiveness (The National Resident Matching Program). Such a combined system allows the state to maintain a balance in the distribution of seats among US citizens and citizens of other states and at the same time strive to attract the best specialists in medicine on an adversarial basis. The study also reveals a pattern in the share of popularity of certain medical specialties among the migratory and non-migratory population, which allows us to draw conclusions about the possibility of a further more or less influx of foreigners into the positions of narrowly targeted doctors. In general, it can be summarized that the analysis of foreign labor on the example of the United States, as well as government measures to stimulate or restrict access by non-residents to this area, is quite significant and in some way useful as a possible strategy to follow for other countries, including the Russian Federation.

Contemporary loss of migration in monarch butterflies

The annual migration of the monarch butterfly Danaus plexippus is in peril. In an effort to aid population recovery, monarch enthusiasts across North America participate in a variety of conservation efforts, including captive rearing and release of monarch butterflies throughout the summer and autumn. However, the impact of captive breeding on monarchs remains an open question. Here, we show that captive breeding, both commercially and by summertime hobbyists, causes migratory behavior to be lost. Monarchs acquired commercially failed to orient south when reared outdoors in the autumn, unlike wild-caught North American monarchs, yet they did enter reproductive diapause. The commercial population was genetically highly divergent from wild-caught North American monarchs and had rounder forewings, similar to monarchs from nonmigratory populations. Furthermore, rearing wild-caught monarchs in an indoor environment mimicking natural migration-inducing conditions failed to elicit southward flight orientation. In fact, merely eclosing indoors after an otherwise complete lifecycle outdoors was enough to disrupt southern orientation. Our results provide a window into the complexity-and remarkable fragility-of migration.

Wing Abnormality in a Wild-Hatched Whooping Crane (Grus americana) Chick from the Nonmigratory Population in Louisiana, USA

We describe a wing abnormality in a wild-hatched Whooping Crane (Grus americana) chick from the reintroduced Louisiana, US nonmigratory population. Despite its seemingly compromised flight ability, the chick fledged, reached independence, and lived until 13 mo of age. Necropsy revealed an axial malunion near the left carpus likely resulting from trauma.

Variation in Deuterium Levels of Non-Migratory Eptesicus fuscus (Big Brown Bat) along the Delmarva Peninsula

Stable-isotope analysis can address fundamental questions about the ecology and life history of mobile organisms. The hydrogen isotope, deuterium (δ2H), follows distinct and predictable patterns along environmental gradients, enabling migratory-origin assignments in vagile animals such as bats. However, it is unclear to what degree deuterium levels vary within non-migratory bat populations in fixed areas. To understand this, we compared deuterium signatures among adult female bats in maternity colonies of non-migratory Mid-Atlantic Eptesicus fuscus (Big Brown Bat). We sampled from 5 different locations along the Delmarva Peninsula. We also compared differences in signatures between males and females within colonies. Despite relative proximity to each other, deuterium signatures of females among colony locations differed significantly. Deuterium signatures did not differ among males and females or between 2010 and 2011. We suggest that variation in foraging and roosting behavior, as well as changes in water sources along the peninsula influence deuterium levels on a small geographic scale. These and other factors should be considered when interpreting sampled deuterium levels.

Urbanization predicts infection risk by a protozoan parasite in non-migratory populations of monarch butterflies from the southern coastal U.S. and Hawaii

Urbanization can affect the density of hosts, altering patterns of infection risk in wildlife. Most studies examining associations between urbanization and host-parasite interactions have focused on vertebrate wildlife that carry zoonotic pathogens, and less is known about responses of other host taxa, including insects. Here we ask whether urban development predicts infection by a protozoan, Ophyrocystis elektroscirrha, in three populations of monarchs (Danaus plexippus): migratory monarchs in northeastern U.S., non-migratory monarchs in southeastern coastal U.S., and non-migratory monarchs in Hawaii. We used impervious surface and developed land cover classes from the National Land Cover Database to derive proportional measures of urban development and an index of land cover aggregation at two spatial scales. Parasite data were from previous field sampling (Hawaii) and a citizen science project focused on monarch infection in North America. Proportional measures of urban development predicted greater infection prevalence for non-migratory monarchs sampled in the southern coastal U.S. and Hawaii, but not in the northern U.S. Aggregations of low intensity development, dominated by single-family housing, predicted greater infection prevalence in monarchs from the northern and southern coastal U.S. populations, but predicted lower infection prevalence in Hawaii. Because natural habitats have been reduced by land-use change, plantings for monarchs in residential areas and urban gardens has become popular among the public. Mechanisms that underlie higher infection prevalence in urban landscapes remain unknown. Further monitoring and experimental studies are needed to inform strategies for habitat management to lower infection risk for monarchs.

Social behavior and changes in foraging behavior in a gregarious ungulate

Large herbivores display restricted area searching and, therefore, in food-rich patches, animals should spend more time feeding, move slowly, and take tortuous movement paths. Intersexual differences in social behavior might disrupt restricted area searching that, in turn, might affect ecological differences between size-dimorphic females and males. We measured time the head was up (head up), step lengths (m/min), and tortuosity of foraging paths in 547 focal observations in a nonmigratory population of Roosevelt elk (Cervus elaphus roosevelti) in Redwood National and State Parks, California, United States. Focal observations were 4–15 min in length. Head up was positively related to proximity (within 1 body length of other elk) for females and males but the slope was steeper for males. When males were aggregated with females, head up was more elevated than when males were aggregated with other males. Sex-specific social behaviors did not influence step length and foraging path tortuosity. Social behavior disrupted efficient foraging. Connecting social behavior to foraging behavior can help explain the numerous ways that size-dimorphic females and males display ecological differences.

Low Genetic Diversity and Low Gene Flow Corresponded to a Weak Genetic Structure of Ruddy-Breasted Crake (Porzana fusca) in China.

The Ruddy-breasted Crake (Porzana fusca) is an extremely poorly known species. Although it is not listed as globally endangered, in recent years, with the interference of climate change and human activities, its habitat is rapidly disappearing and its populations have been shrinking. There are two different life history traits for Ruddy-breasted Crake in China, i.e., non-migratory population in the south and migratory population in the north of China. In this study, mitochondrial control sequences and microsatellite datasets of 88 individuals sampled from 8 sites were applied to analyze their genetic diversity, genetic differentiation, and genetic structure. Our results indicated that low genetic diversity and genetic differentiation exit in most populations. The neutrality test suggested significantly negative Fu's Fs value, which, in combination with detection of the mismatch distribution, indicated that population expansion occurred in the interglacier approximately 98,000years ago, and the time of the most recent common ancestor (TMRCA) was estimated to about 202,705years ago. Gene flow analysis implied that the gene flow was low, but gene exchange was frequent among adjacent populations. Both phylogenetic and STRUCTURE analyses implied weak genetic structure. In general, the genetic diversity, gene flow, and genetic structure of Ruddy-breasted Crake were low.

Humpback whale singing activity off the Goan coast in the Eastern Arabian Sea

For over two decades, passive acoustic monitoring (PAM) methods have been successfully employed around the world for studying aquatic megafauna. PAM-driven studies in Indian waters have so far been relatively very scarce. Furthermore, cetacean populations inhabiting the north western Indian Ocean are far less studied than those in many other regions around the world. This work likely constitutes the first systematic study of the vocal repertoire of humpback whales (Megaptera novaeangliae) at a near-shore site along the western coast of India. Analysis of the observed vocalizations provides an insight into the behaviour of the species. This is significant as it assists in developing a better understanding of the habitat use of the non-migratory Arabian Sea humpback whale population. In contrast, other breeding populations such as those around the North Atlantic, South Pacific and Australia have been relatively well studied. Underwater passive acoustic data were collected during March 2017 using an autonomous logger at a shallow-water site off the eastern edge of Grande Island off the coast of Goa. Humpback whale vocalizations were found to occur over multiple days in the recordings. Time–frequency contours of individual units of vocalization were extracted with the aid of an automatic detection technique and the characteristics of the units were measured. Further, successive units were analysed for formation of phrases and themes. Reconstruction of putative songs from the identified units and themes was not possible due to the limitations imposed by the nature of data collection. Detailed analyses of units, phrases and themes are presented.