Pedigrees and the Study of the Wild Horse Population of Assateague Island National Seashore

Recently, a number of papers have addressed the use of pedigrees in the study of wild populations, highlighting the value of pedigrees in conservation management. We used pedigrees to study the horses (Equus caballus) of Assateague Island National Seashore, Maryland, USA, one of a small number of free-ranging animal populations that have been the subject of long-term studies. This population grew from 28 in 1968 to 175 in 2001, causing negative impacts on the island ecosystem. To minimize these effects, an immunocontraception program was instituted, and horse numbers are slowly decreasing. However, there is concern that this program may negatively affect the genetic health of the herd. We found that although mitochondrial DNA diversity is low, nuclear diversity is comparable to that of established breeds. Using genetic data, we verified and amended maternal pedigrees that had been primarily based on behavioral data and inferred paternity using genetic data along with National Park Service records of the historic ranges of males. The resulting pedigrees enabled us to examine demography, founder contributions, rates of inbreeding and loss of diversity over recent generations, as well as the level of kinship among horses. We then evaluated the strategy of removing individuals (using nonlethal means) with the highest mean kinship values. Although the removal strategy increased the retained diversity of founders and decreased average kinship between individuals, it disproportionately impacted sizes of the youngest age classes. Our results suggest that a combined strategy of controlled breeding and immunocontraception would be more effective than removing individuals with high mean kinships in preserving the long-term health and viability of the herd. © 2010 The Wildlife Society

Whole genome sequencing of California condors is now utilized for guiding genetic management

The California condor is a critically endangered avian species that, in 1982, became extinct in the wild. Its survival has persevered through a captive breeding program and reintroduction efforts within its former range. As of April, 2015, 421 California condors, including 204 flying in the wild constituted the extant population. Concern regarding preservation of genetic diversity and inbreeding, have led to intensive population management supported by molecular genetics research and, more recently, the application of genomic methodologies. 36 complete California condor genomes, representing the whole gene pool of the species, have been sequenced identifying about 4 millions polymorphic sites (SNPs). This has allowed reassessment of kinship among the founder birds, which is now being applied to selecting breeding pairs for the ongoing captive propagation effort. A genetic disease, chondrodystrophy, is inherited consistent with an autosomal recessive mode of transmission in condors. Utilizing whole genome sequencing of affected chicks and their carrier parents, a series of linked markers localized in a 1 Mb region of the condor genome have been employed to detect carrier condors heterozygous for the lethal mutation. This information can be incorporated into population management to reduce the risk of reproductive failure, as reintroduced populations begin to expand

Supporting California condor conservation management through analysis of species-wide whole genome sequence variation

The critically endangered California condor (Gymnogyps californianus) has been the focus of intensive conservation efforts for several decades. Reduced to a population size of twenty-three birds in 1985, the entire surviving population was brought under captive management for recovery. Founded by fourteen individuals, the surviving California condor gene pool has been managed through captive breeding of individuals paired through pedigree analysis. As of August, 2013, there were 424 California condor individuals; 223 are flying in the wild in four re-introduced populations in California, Arizona and Baja California, Mexico. All condors have their sex identified via amplification of sex chromosome specific markers and DNA samples are stored for every individual of the species. Microsatellite genotyping has confirmed parentage in captive and wild condor chicks, corrected switched identities, and identified successful extra-pair copulation in the wild population. Whole genome sequencing using data generated on multiple platforms has been used to produce a de novo genome assembly for a founder male condor and thirty additional condors that together encompass the entire genetic variation of the species, perhaps the first time such a comprehensive effort has been conducted for any species. Studbook-based kinship relationships between founder birds and kinship estimates from genome-wide genetic variation can be compared and evaluated in the context of retention of genetic diversity in the generations of California condors. Genomic studies of California condors are providing a model system for avian conservation genomics and allow empirical evaluation of basic facets of transmission genetics, including segregation, linkage, recombination and mutation

Landsat 9 TIRS-2 Architecture and Design

TIRS-2 will fly on the LandSat 9. Like TIRS on Landsat 8, TIRS-2 will produce radiometrically calibrated, geo-located thermal image data. USGS is responsible for operational code. TIRS-2 image data will have the same performance characteristics as that of TIRS on Landsat 8 except better in some cases

Introduction Conservation Genetics

xxi,617 hal,;ill,;25 c

Inbreeding and outbreeding

Inbreeding refers to mating of related individuals. It results in a decline in survival and reproduction (reproductive fitness), known as inbreeding depression, in most species of plants and animals. Outbreeding refers to matings between individuals from different populations, subspecies, or species. Outbreeding can result in a decline in reproductive fitness known as outbreeding depression, but this is less common than inbreeding depression. Inbreeding in small populations typically increases extinction risk, especially for species that do not normally inbreed. Outbreeding between populations with chromosomal incompatibilities or those that are adapted to different environmental conditions can also increase extinction risk. Restoring gene flow between isolated populations can reverse inbreeding depression. This article discusses the conservation implications of inbreeding and outbreeding depression.8 page(s

A primer of conservation genetics

Cambridgevii, 220.: illus.; 27 c

A Primer of conservation genetics

The biological diversity of our planet is rapidly being depleted due to direct and indirect consequences of human activities. As the size of animal and plant populations decreases, loss of genetic diversity reduces their ability to adapt to changes in the environment, with inbreeding depression an inevitable consequence for many species. This concise, entry-level text provides an introduction to the role of genetics in conservation and presents the essentials of the discipline. Topics covered include: loss of genetic diversity in small populations, inbreeding and loss of fitness, resolution of taxonomic uncertainties, genetic management of threatened species, contributions of molecular genetics to conservation. The authors assume only a basic knowledge of Mendelian genetics and simple statistics, making the book accessible to those with a limited background in these areas. Connections between conservation genetics and the wider field of conservation biology are interwoven throughout the book.Ch. 1. Introduction -- Ch. 2. Genetic diversity -- Ch. 3. Evolutionary genetics of natural populations -- Ch. 4. Genetic consequences of small population size -- Ch. 5. Genetics and extinction -- Ch. 6. Resolving taxonomic uncertainties and defining management units -- Ch. 7. Genetic management of endangered species in the wild -- Ch. 8. Captive breeding and reintroduction -- Ch. 9. Molecular genetics in forensics and understanding species biology

Introduction to conservation genetics

The biological diversity of our planet is being depleted due to the direct and indirect consequences of human activity. As the size of animal and plant populations decrease, loss of genetic diversity reduces their ability to adapt to changes in the environment, with inbreeding depression an inevitable consequence for many species. This textbook provides a clear and comprehensive introduction to the importance of genetic studies in conservation. The text is presented in an easy-to-follow format with main points and terms clearly highlighted. Each chapter concludes with a concise summary, which, together with worked examples and problems and answers, emphasise the key principles covered. Text boxes containing interesting case studies and other additional information enrich the content throughout, and over 100 beautiful pen and ink portraits of endangered species help bring the material to life

Introduction to conservation genetics

This impressive author team brings the wealth of advances in conservation genetics into the new edition of this introductory text, including new chapters on Population genomics and Genetic issues in introduced and invasive species. They continue the strong learning features for students - main points in the margin, chapter summaries, vital support with the mathematics, and further reading - and now guide the reader to software and databases. Many new references reflect the expansion of this field. With examples from mammals, birds, reptiles, fish, amphibians, plants and invertebrates, this is an ideal introduction to conservation genetics for a broad audience. The text tackles the quantitative aspects of conservation genetics, and has a host of pedagogy to support students learning the numerical side of the subject. Combined with being up-to-date, its user-friendly writing style and a first-class illustration programme, this forms a robust teaching package.618 page(s)2nd ed