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Conservation Programmes (conservation + programme)

Distribution by Scientific Domains

Life Sciences	81%
Medical Sciences	12%
2 Other Domains	7%

Distribution within Life Sciences

Ecology & Organismal Biology	18%
Animal Science & Zoology	11%
Evolution	7%

Selected Abstracts

Is sustainable development based on agriculture attainable in Kenya?

LAND DEGRADATION AND DEVELOPMENT, Issue 5 2001
A multidisciplinary case study of Murang'a district
Abstract Kenya's development seems trapped in a vicious circle caused by soil erosion, declining soil fertility, land fragmentation, fluctuating agricultural production, widespread poverty, corruption, ethnic tension, rapid population, urban growth and a declining economy. The development challenge is to reverse the negative effects of these processes and promote sustainable development. This paper, based on multidisciplinary work discusses whether sustainable development based on agriculture is attainable in Murang'a district in Kenya's Central Highlands. Firstly, it investigates some biophysical aspects of sustainable agriculture such as land use across time, soil nutrient status and yield, cultivated crops and soil productivity by analysing aerial photographs and soil samples and conducting interviews. It suggests that the area has gone through major biophysical changes. Second, it relates the farmers' attitude to promotion of sustainable development as carried out by the National Soil and Water Conservation Programme. It suggests that farmers carry ideas of corruption, often following ethnic lines that hampers efficient implementation of the extension advise. Finally, it identifies links behind rural-urban migration by estimating households' probability of generating incomes outside the farm, typically in urban areas. Opportunistic farming, manifested by temporary reduction of farming on own land to satisfy immediate income needs, is very common among farmers. More needs to be done to promote agro-based, small-scale rural industries, improve agricultural management practices, facilitate appropriate credits, enhance marketing opportunities, ensure timely crop payments, and increase participation in decision making. It is important to realize that for farmers to embrace policies which promote agriculturely-based sustainable development the policies ought to biophysically possible, socio-politically acceptable and economically feasible. Copyright © 2001 John Wiley & Sons, Ltd. [source]

Migratory connectivity in a declining bird species: using feather isotopes to inform demographic modelling

DIVERSITY AND DISTRIBUTIONS, Issue 4 2010
Thomas S. Reichlin
Abstract Aim, Conservation programmes for endangered migratory species or populations require locating and evaluating breeding, stopover and wintering areas. We used multiple stable isotopes in two endangered European populations of wrynecks, Jynx torquilla L., to locate wintering regions and assess the degree of migratory connectivity between breeding and wintering populations. Location, Switzerland and Germany. Methods, We analysed stable nitrogen (,15N), carbon (,13C) and hydrogen (,D) isotopes from wing feathers from two populations of wrynecks to infer their wintering origins and to assess the strength of migratory connectivity. We tested whether variation in feather isotopic values within the Swiss population was affected by bird age and collection year and then considered differences in isotopic values between the two breeding populations. We used isotopic values of summer- and winter-grown feathers to estimate seasonal distributions. Finally, we calculated a species-specific ,D discrimination factor between feathers and mean annual ,D values to assign winter-grown feathers to origin. Results, Bird age and collection year caused substantial isotopic variation in winter-grown feathers, which may be because of annually variable weather conditions, movements of birds among wintering sites and/or reflect asynchronous moulting or selection pressure. The large isotopic variance in winter-grown feathers nevertheless suggested low migratory connectivity for each breeding population, with partially overlapping wintering regions for the two populations. Main conclusions, Isotopic variance in winter-grown feathers of two breeding populations of wrynecks and their geographical assignment point to defined, albeit overlapping, wintering areas, suggesting both leapfrog migration and low migratory connectivity. On this basis, integrative demographic models can be built looking at seasonal survival patterns with links to local environmental conditions on both breeding and wintering grounds, which may elucidate causes of declines in migratory bird species. [source]

Conservation programmes for African cattle: design, cost and benefits

JOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 2 2005
S.B. Reist-Marti
Summary Information on costs and benefits of conservation programmes for cattle is scarce in the literature and mainly available for Europe. This study aims at simulating cost of and benefits from different kinds of conservation programmes designed for indigenous African cattle. The programmes include installation of a herdbook and activities to promote the breed (HB), in situ conservation with a sire rotation scheme (IS), cryoconservation of semen (CC) and CC combined with in situ conservation (IC). The results indicate that cost of the analysed conservation programmes was generally higher than those reported in the literature for comparable schemes. If cost per effective population size conserved is considered, programmes analysed in this study do not appear to be more expensive. The proposed rotation scheme in IS can be applied to many different production systems and prove to be effective with regard to low increase in kinship. Reduction in extinction probability is found to be higher for conservation programmes that strongly involve farmers and give them part of the responsibility for the breeding population. IC was most efficient with regard to cost per effective population size conserved. However, if cost per reduction in endangerment is considered as criterion for the efficiency of a programme, IS, HB and CC are superior to IC. These findings suggest that decisions on conservation programmes should be based on multiple criteria, and not just on cost per effective population size. [source]

Integrated blood conservation programme to minimise blood loss and transfusion requirements in hepatic resection

HPB, Issue 4 2002
A Serrablo
No abstract is available for this article. [source]

Flying an amphibian flagship: conservation of the Axolotl Ambystoma mexicanum through nature tourism at Lake Xochimilco, Mexico

INTERNATIONAL ZOO YEARBOOK, Issue 1 2008
I. G. BRIDE
The effectiveness of flagship species as a conservation tool is controversial, and amphibians are not usually regarded as meeting the strategic criteria that flagships demand. Capitalizing on the historical, cultural and economic importance of the Axolotl Ambystoma mexicanum at Lake Xochimilco, Mexico, a conservation programme for this species and its habitat was developed using the Axolotl as a flagship. The threats to the lake are complex and stem from the unsustainable use of its resources. The needs and livelihoods of local stakeholders must therefore be taken into account before attempting to address the threats. The programme therefore focused on developing nature tourism by training local boatmen (remeros) in environmental interpretation. Surveys showed that the boatmen increased their incomes and job satisfaction after training, and that the environmental interpretation programme improved relevant knowledge and awareness of visitors. Although ongoing threats mean that reintroduction of captive-bred Axolotls is not appropriate, zoos with captive populations of Axolotls supported the programme regionally and internationally by providing publicity, funds, staff expertise, training support and themed educational activities. By raising both funds and awareness for the wider conservation of Lake Xochimilco, the Axolotl is probably the first amphibian flagship to be launched successfully. [source]

Conservation strategy maps: a tool to facilitate biodiversity action planning illustrated using the heath fritillary butterfly

JOURNAL OF APPLIED ECOLOGY, Issue 2 2003
G. J. Holloway
Summary 1.,The UK Biodiversity Action Plan (UKBAP) identifies invertebrate species in danger of national extinction. For many of these species, targets for recovery specify the number of populations that should exist by a specific future date but offer no procedure to plan strategically to achieve the target for any species. 2.,Here we describe techniques based upon geographic information systems (GIS) that produce conservation strategy maps (CSM) to assist with achieving recovery targets based on all available and relevant information. 3.,The heath fritillary Mellicta athalia is a UKBAP species used here to illustrate the use of CSM. A phase 1 habitat survey was used to identify habitat polygons across the county of Kent, UK. These were systematically filtered using relevant habitat, botanical and autecological data to identify seven types of polygon, including those with extant colonies or in the vicinity of extant colonies, areas managed for conservation but without colonies, and polygons that had the appropriate habitat structure and may therefore be suitable for reintroduction. 4.,Five clusters of polygons of interest were found across the study area. The CSM of two of them are illustrated here: the Blean Wood complex, which contains the existing colonies of heath fritillary in Kent, and the Orlestone Forest complex, which offers opportunities for reintroduction. 5.,Synthesis and applications. Although the CSM concept is illustrated here for the UK, we suggest that CSM could be part of species conservation programmes throughout the world. CSM are dynamic and should be stored in electronic format, preferably on the world-wide web, so that they can be easily viewed and updated. CSM can be used to illustrate opportunities and to develop strategies with scientists and non-scientists, enabling the engagement of all communities in a conservation programme. CSM for different years can be presented to illustrate the progress of a plan or to provide continuous feedback on how a field scenario develops. [source]

Does designation of protected areas ensure conservation of tree diversity in the Sudanian dry forest of Burkina Faso?

AFRICAN JOURNAL OF ECOLOGY, Issue 2 2010
Souleymane Paré
Abstract The importance of conservation status of the forest (protected versus unprotected) at two sites with differing human population density (high versus low) on the tree diversity of a Sudanian dry forest in Burkina Faso was studied. All woody species were recorded in 127 circular plots (area = 456.16 m2), and density, dominance, frequency, importance value indices and a variety of diversity measures were calculated to assess the species composition, structure and heterogeneity. A total of 69 species, representing 26 families and 52 genera, were found. Combretaceae, Leguminosae subfamily Caesalpinioideae and Rubiaceae were the dominant families. Neither human pressure nor forest conservation status significantly influenced the tree species richness. Stem density and basal area were significantly higher at the site with high population density than otherwise. Fisher's diversity index revealed the unprotected forest at the site with low population density as the most diverse. We identified species with high conservation importance that should be enriched to maintain a viable population size. In conclusion, the current designation of protected areas seems inefficient at ensuring the conservation of tree diversity in the forest reserve. Thus, participatory conservation programme should be initiated. Résumé À deux endroits où la densité de population humaine est différente (forte versus faible), nous avons étudié l'importance du statut de conservation de la forêt (protégée ou non) pour la diversité d'une forêt soudanienne sèche du Burkina Faso. On a enregistré toutes les espèces ligneuses sur 127 parcelles circulaires (superficie = 456,16 m²), et on a calculé la densité, la dominance, les indices de valeurs d'importance value et une variété de mesures de diversité pour évaluer la composition, la structure et l'hétérogénéité des espèces. On a découvert un total de 69 espèces, représentant 26 familles et 52 genres. Les familles dominantes étaient Combretaceae, Leguminosae de la sous-famille Caesalpinioideae, et Rubiaceae. Ni la pression humaine, ni le statut de conservation des forêts n'influençaient significativement la richesse en espèces d'arbres. La densité des troncs et la surface terrière à la base étaient significativement plus élevées sur le site à forte densité de population. L'indice de diversité de Fisher a permis de révéler que la forêt non protégée du site à faible densité de population était la plus diversifiée. Nous avons identifié des espèces de haute valeur de conservation qui devraient être enrichies pour préserver une taille de population viable. En conclusion, la désignation actuelle d'aires protégées semble inefficace pour assurer la conservation de la diversité des arbres dans la réserve forestière. Donc, il faudrait initier un programme de conservation participative. [source]

Early age reproduction in female savanna elephants (Loxodonta africana) after severe poaching

AFRICAN JOURNAL OF ECOLOGY, Issue 2 2009
M. J. Owens
Abstract A 10-year study revealed that after severe poaching (>93% killed) of elephants (Loxodonta africana) in Zambia's North Luangwa National Park (NLNP) during the 1970s and 1980s, the age of reproduction in females was greatly reduced. Fifty-eight per cent of births were delivered by females aged 8.5,14 years, an age at which elephants were reported to be sexually immature in nearby South Luangwa National Park (SLNP) before poaching. The mean age of females at first birth (AFB) (1993, 1994) was 11.3 years. Prior to poaching, the mean age AFB in SLNP was 16 years. The NLNP age structure and sex ratio were skewed, mean family unit size was reduced, and 37% of family units contained no females older than 15 years. Twenty-eight per cent of family units were comprised entirely of a single mother and her calf, and 8% of units consisted only of orphans who would have been considered sexually immature prior to poaching. Only 6% of survivors were older than 20 years, the age at which females in little-poached populations generally become most reproductively active. After a community-based conservation programme and the UN-CITES ban on the ivory trade were introduced, no elephants were recorded killed. In spite of a high reproductive rate, 6 years after poaching decreased, the density of the NLNP population had not increased, supporting predictions that the removal of older matriarchs from family units will have serious consequences on the recovery of this species. Résumé Une étude qui a duré dix ans a révélé qu'après un braconnage très grave (>93% tués) des éléphants (Loxodonta africana) dans le Parc National de Luangwa Nord (NLNP), en Zambie au cours des années 1970 et 1980, l'âge de la reproduction chez les femelles a fort baissé. Cinquante-huit pour cent des naissances se sont passées chez des femelles qui avaient entre 8,5 et 14 ans, un âge auquel les éléphants étaient dits être encore sexuellement immatures dans le Parc National de Luangwa Sud (SLNP), tout proche, avant le braconnage. L'âge moyen des femelles à la première mise-bas (AFB ,at first birth) (1993, 1994) était de 11,3 ans. Avant le braconnage, l'âge moyen à la première mise-bas était de 16 ans au SLNP. Au NLNP, la structure d'âge et le sex-ratio ont été faussés, la taille moyenne de l'unité familiale a été réduite, et 37% des familles ne contiennent aucune femelle de plus de 15 ans. Vingt-huit pour cent des unités familiales n'étaient composées que d'une mère seule et de son jeune, et huit pour cent n'étaient composées que d'orphelins qui devaient être considérés comme sexuellement immatures avant le braconnage. Seuls six pour cent des survivants avaient plus de 20 ans, l'âge auquel les femelles de populations peu braconnées deviennent généralement les plus actives en matière de reproduction. Après l'introduction d'un programme de conservation communautaire et l'interdiction, par la CITES-UN, du commerce de l'ivoire, on n'a plus enregistré aucun massacre d'éléphant. Malgré un taux élevé de reproduction, la densité de population du NLNP n'a pas augmenté, ce qui conforte les prédictions que l'enlèvement des plus vieilles matriarches des unités familiales aura de sérieuses conséquences sur la restauration de cette espèce. [source]

Long-term population isolation in the endangered tropical tree species Caesalpinia echinata Lam. revealed by chloroplast microsatellites

MOLECULAR ECOLOGY, Issue 12 2003
C. F. Lira
Abstract Habitat fragmentation represents the single most serious threat to the survival of tropical ecosystems. In formulating strategies to counteract the detrimental effects of fragmentation, knowledge of the levels and patterns of genetic diversity within and between natural populations is vital to the establishment of any conservation programme. We utilized polymorphic chloroplast microsatellite markers to analyse genetic diversity in populations of the endangered tropical tree Caesalpinia echinata Lam. representing the entire extant range of the species. Levels of within-population diversity were low, with only two of seven populations studied displaying any variation. The vast majority of the genetic variation was partitioned between geographical regions (36%) and between populations within regions (55%). These levels of genetic structuring, coupled with a calculated pollen-to-seed flow ratio of , 6.7:1, suggest that there has been little gene flow between the three major geographical regions over an extended period. Thus, the current tripartite distribution of the species is more consistent with the existence of separate glacial refugia, rather than reflecting any anthropogenic effects. [source]

Genetic structure and differentiation of the Japanese extremely long-tailed chicken breed (Onagadori), associated with plumage colour variation: suggestions for its management and conservation

ANIMAL GENETICS, Issue 6 2009
R. Tadano
Summary The Onagadori is a distinguished chicken breed that is characterized by an extremely long tail in the male. In this breed, three different plumage colour varieties have been developed (black-breasted white, black-breasted red and white) in which the black-breasted white is believed to be the original colour of the Onagadori, based on historical records. To establish a conservation strategy, 176 birds were genotyped for autosomal microsatellites. Significant genetic distinctness was found between the original (black-breasted white) and two derivative varieties (FST = 0.091 and 0.093). At the same time, a Bayesian model-based clustering revealed that the majority of individuals belonging to the black-breasted red and white varieties had an extremely low proportion of the genome shared with the original type (black-breasted white). This suggests that derivative varieties were created by crossing with other breeds, with low introgression of the original-type genome. We propose that the three plumage colour varieties should be treated as separate genetic units in a conservation programme. [source]

Genetic diversity within and between European pig breeds using microsatellite markers

ANIMAL GENETICS, Issue 3 2006
M. SanCristobal
Summary An important prerequisite for a conservation programme is a comprehensive description of genetic diversity. The aim of this study was to use anonymous genetic markers to assess the between- and the within-population components of genetic diversity for European pig breeds at the scale of the whole continent using microsatellites. Fifty-eight European pig breeds and lines were analysed including local breeds, national varieties of international breeds and commercial lines. A sample of the Chinese Meishan breed was also included. Eleven additional breeds from a previous project were added for some analyses. Approximately 50 individuals per breed were genotyped for a maximum of 50 microsatellite loci. Substantial within-breed variability was observed, with the average expected heterozygosity and observed number of alleles per locus being 0.56 [range 0.43,0.68] and 4.5 respectively. Genotypic frequencies departed from Hardy,Weinberg expectations (P < 0.01) in 15 European populations, with an excess of homozygotes in 12 of them. The European breeds were on average genetically very distinct, with a Wright FST index value of 0.21. The Neighbour-Joining tree drawn from the Reynolds distances among the breeds showed that the national varieties of major breeds and the commercial lines were mostly clustered around their breeds of reference (Duroc, Hampshire, Landrace, Large White and Piétrain). In contrast, local breeds, with the exception of the Iberian breeds, exhibited a star-like topology. The results are discussed in the light of various forces, which may have driven the recent evolution of European pig breeds. This study has consequences for the interpretation of biodiversity results and will be of importance for future conservation programmes. [source]

Estimation of genetic variability of the founder population in a conservation scheme using microsatellites

ANIMAL GENETICS, Issue 3 2003
M. A. Toro
Summary In a conservation programme with genealogical records it is possible to estimate the amount of variability of the founder population from a measure of the similarity among the individuals in the current population based on microsatellite markers. Here we compare three available methods and we shown that the one based on the molecular coancestry coefficient should be preferred. [source]

Effects of tidal flat reclamation on sediment quality and hypoxia in Isahaya Bay

AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2006
Yoshikuni Hodoki
Abstract 1.Ariake Bay, which is located in western Japan, has a large tidal range (>6 m) and a vast tidal flat (200 km2). In the early 1990s, the government-managed Isahaya Reclamation Project began in the western part of Ariake Bay. A 16-km2 area of tidal flat in the inner part of Isahaya Bay was destroyed through reclamation and separated from the sea by a dyke, which created land and a freshwater reservoir. 2.Since the initiation of the project, fishery yields around Isahaya Bay have dramatically decreased. The objective of this study was to clarify the relationship between the work associated with the Isahaya Reclamation Project and the recent environmental deterioration in Ariake Bay, with references to present sediment thickness and organic matter content, and hypoxic water distributions in Isahaya Bay. 3.The organic matter load from the reservoir has increased since the initiation of the reclamation project and has been associated with a thick layer of fine sediment at the bottom of Isahaya Bay. The thickness of fine sediment and the total organic carbon content were higher in Isahaya Bay than in the freshwater reservoir. 4.Based on measurements in August 2001, hypoxic water spread widely in and around Isahaya Bay; the lowest dissolved oxygen (DO) concentration (0.53 mg L,1) was observed just outside the dyke. An analysis based on a two-layered box model using data obtained in August 2001 showed that the DO consumption rate in the bottom layer was high (0.61 mg O2 L,1 day,1), and that 22,41% of the total organic carbon load needed to induce the hypoxic water was derived from the reclamation area. 5.Our findings strongly suggest that enclosed seas may suffer from eutrophic and hypoxic conditions because of their low seawater-exchange rate. A comprehensive conservation programme and environmental assessment including physical and material transport processes in the system is needed to manage the environment of the enclosed sea. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Salinity tolerance in young Allis shad larvae (Alosa alosa L.)

ECOLOGY OF FRESHWATER FISH, Issue 1 2008
A. Bardonnet
Abstract,,, Estuarine migration in Allis shad (Alosa alosa) usually does not take place before mid-summer, but exposure to salinity in brackish water may occur earlier as many spawning areas are of necessity located in upper estuarine zones due to the placement of dams. Therefore, Allis shad conservation programmes need to consider the risk of mortality due to the ability of young Allis shad to tolerate salinity. To evaluate larval mortality due to the inability of larvae to withstand salinity during early ontogeny, we exposed larvae of different ages (from few days old to 27 days old) to salinities ranging from 0 to 30 g·l,1. Results indicate that direct seawater exposure induces high mortality in young larvae whatever the ontogenetic stage. However, young larvae can easily deal with upper estuary salinity conditions. [source]

The role of zoos in the 21st century,

INTERNATIONAL ZOO YEARBOOK, Issue 1 2003
W. Conway
Zoos have been overtaken by the rapidity of wildlife extinction and most of their conservation programmes are unresponsive. To fulfil their obligations to society, and to survive, zoos must become proactive conservation organizations, applying their popularity to win support for wildlife protection and their expertise to help sustain reduced numbers of wildlife in marginal habitats. [source]

Conservation programmes for African cattle: design, cost and benefits

Multi-scale occupancy estimation and modelling using multiple detection methods

JOURNAL OF APPLIED ECOLOGY, Issue 5 2008
James D. Nichols
Summary 1Occupancy estimation and modelling based on detection,nondetection data provide an effective way of exploring change in a species' distribution across time and space in cases where the species is not always detected with certainty. Today, many monitoring programmes target multiple species, or life stages within a species, requiring the use of multiple detection methods. When multiple methods or devices are used at the same sample sites, animals can be detected by more than one method. 2We develop occupancy models for multiple detection methods that permit simultaneous use of data from all methods for inference about method-specific detection probabilities. Moreover, the approach permits estimation of occupancy at two spatial scales: the larger scale corresponds to species' use of a sample unit, whereas the smaller scale corresponds to presence of the species at the local sample station or site. 3We apply the models to data collected on two different vertebrate species: striped skunks Mephitis mephitis and red salamanders Pseudotriton ruber. For striped skunks, large-scale occupancy estimates were consistent between two sampling seasons. Small-scale occupancy probabilities were slightly lower in the late winter/spring when skunks tend to conserve energy, and movements are limited to males in search of females for breeding. There was strong evidence of method-specific detection probabilities for skunks. As anticipated, large- and small-scale occupancy areas completely overlapped for red salamanders. The analyses provided weak evidence of method-specific detection probabilities for this species. 4Synthesis and applications. Increasingly, many studies are utilizing multiple detection methods at sampling locations. The modelling approach presented here makes efficient use of detections from multiple methods to estimate occupancy probabilities at two spatial scales and to compare detection probabilities associated with different detection methods. The models can be viewed as another variation of Pollock's robust design and may be applicable to a wide variety of scenarios where species occur in an area but are not always near the sampled locations. The estimation approach is likely to be especially useful in multispecies conservation programmes by providing efficient estimates using multiple detection devices and by providing device-specific detection probability estimates for use in survey design. [source]

The relative roles of domestication, rearing environment, prior residence and body size in deciding territorial contests between hatchery and wild juvenile salmon

JOURNAL OF APPLIED ECOLOGY, Issue 3 2003
Neil B. Metcalfe
Summary 1Interactions between captive-reared and wild salmonids are frequent because hatcheries annually rear millions of fish for release in conservation programmes while many thousands of domesticated fish escape from fish farms. However, the outcome of competition between captive-reared and wild fish is not clear: wild fish may be smaller and less aggressive than hatchery fish, but they have more local experience and a prior residence advantage. Moreover, it is important to know whether any competitive differences are genetic (due to the process of domestication) or due to the rearing environment. 2We therefore examined the factors influencing competition for feeding territories in juvenile Atlantic salmon. We studied the effect of domestication by using three independent stocks of both domesticated and wild-origin fish, all of which were reared in a common hatchery environment. We also used fish from the same wild stocks that had been living in the wild. Territorial contests were staged in stream tank compartments between pairs of fish differing in origin or rearing environment; the relative importance of body size and prior residence was also assessed. 3All three stocks of domesticated fish were generally dominant over wild-origin fish when both had been raised in a common hatchery environment. If the wild-origin fish were given a 2-day period of prior residence on the territory this asymmetry in dominance was reversed. However, domesticated fish did not gain any additional advantage from being prior residents. The relative body size of the two contestants had a negligible effect on contest outcomes. 4Truly wild fish (i.e. those of wild origin that had also grown up in the wild) were generally dominant over domesticated or wild-origin fish that had been hatchery-reared. Differences in body size between contestants had no effect on the outcome. 5Synthesis and applications. These results show that, while juvenile farmed Atlantic salmon are inherently more aggressive than wild-origin fish, the hatchery environment reduces their ability to compete for territories with wild resident fish. Rearing salmon in conventional hatcheries for later release into the wild where natural populations already exist may not be a prudent conservation measure; it is preferable to plant eggs or first-feeding fry rather than attempt to ,help' the fish by rearing them through the early life stages. [source]

Conservation strategy maps: a tool to facilitate biodiversity action planning illustrated using the heath fritillary butterfly

Evidence of pesticide resistance in medium-sized mammalian pests: a case study with 1080 poison and Australian rabbits

JOURNAL OF APPLIED ECOLOGY, Issue 4 2002
Laurie E. Twigg
Summary 1Toxicant-resistance is a potential, or very real, problem with many pest-control programmes world-wide. However, apart from rodents, pesticide-resistance has not been well documented in vertebrates. We assessed the potential impact of developing resistance to 1080 in rabbit populations with differing levels of historical exposure to 1080-baiting programmes in south-western Australia. 2The sensitivity to 1080 of three out of the four populations of rabbits Oryctolagus cuniculus examined had decreased significantly since Australian rabbits were last tested over 25 years ago. The lethal dose50 (LD50) values for these populations, as determined from formal toxicity trials, ranged from 0·744 to 1·019 mg pure 1080 kg,1, and were significantly greater (P < 0·05) than the previously reported values for Australian rabbits (LD50 range 0·34,0·46 mg pure 1080 kg,1). The LD50 value for the fourth population (0·584 mg pure 1080 kg,1), which has had the least exposure to 1080, did not differ from that reported previously (P > 0·05). 3The lethal dose99 (LD99) values for the four rabbit populations tested ranged from 1·181 to 1·666 mg pure 1080 kg,1, and suggested that, theoretically, all rabbits should be killed during routine baiting campaigns provided that there is no loss of active ingredient from the bait. In reality, the efficacy of 1080 poison bait laid in trails for controlling free-ranging rabbits was reduced in those populations where rabbits had decreased sensitivity to 1080. Mean reductions in rabbit numbers 7,9 days after trail baiting of resistant and sensitive populations ranged from 51·2% to 65·2%, and from 76·4% to 76·5%, respectively. 4These findings suggest that genetic resistance to 1080 is developing in at least some populations of Australian rabbits. This has world-wide implications for agricultural protection and wildlife conservation programmes that rely on a 1080-baiting strategy for reducing the impact of vertebrate pests. [source]

Contrasting phylogeographical patterns of two closely related species, Machilus thunbergii and Machilus kusanoi (Lauraceae), in Taiwan

JOURNAL OF BIOGEOGRAPHY, Issue 5 2006
Su-Hwa Wu
Abstract Aim, The purpose of this paper was to study the patterns of genetic variation, demographic history, haplotype relationships and potential location of diversity centres of two closely related species, Machilus thunbergii and Machilus kusanoi. Location, The phylogeography of M. thunbergii and M. kusanoi was examined by sampling 110 and 106 individuals from 25 and 16 sampling sites, respectively, across their distributional range in Taiwan. Machilus thunbergii is distributed on the Asian mainland, South Korea, southern Japan, the Ryukyus, Taiwan and the Philippines, whereas M. kusanoi is endemic to Taiwan. These two species are closely related, and both are widely distributed in Taiwan but occupy different altitudinal zones and habitats. Methods, The range-wide variation of M. thunbergii and M. kusanoi in Taiwan was studied using chloroplast DNA (cpDNA) variations. A haplotype network was constructed with the computer program tcs. Nested clade analysis was conducted with the computer program ceodis, and various parameters of genetic diversity were calculated and neutrality tested by the computer program DnaSP. Population differentiation was estimated using the programs arlequin and hapstep. The contribution of the populations to gene diversity and to allelic richness was calculated using the software contrib. The level of divergence for each population from the remaining populations was calculated as the mean value of pairwise FST for each population against the rest of the populations. Results, Extremely low levels of genetic differentiation were found for both species. This result suggested that these two species probably survived in multiple relict refugia with different population sizes throughout the island during low-temperature periods of the Pleistocene. In addition, nested clade analysis (NCA) of cpDNA haplotypes indicated that restricted gene flow with isolation-by-distance characterized the recolonization after the Pleistocene by Tashueshan and Shiouhluan populations of M. thunbergii in the north-central area west of the Central Mountain Range (CMR). In contrast, NCA analysis indicated that a major diversity centre on the southern tip of the island (Kending population) and contiguous range expansion characterized the recolonization by M. kusanoi of northern areas along the east side of the CMR. The major diversity centres found for the two species examined were further supported by the results of the mean FST for individual populations in comparison with other populations, and of the contribution of the divergence component to the total diversity. Main conclusions, This research supports the multiple relict refugia hypothesis for both species investigated. Populations of M. thunbergii at Shiouhluan and Tashueshan in the north-central area west of the CMR represent a diversity centre currently expanding its size. A diversity centre at the southern-edge population of M. kusanoi, and a contiguous range expansion from Kending, were found. These results indicate that the M. thunbergii populations at Tashueshan and Shiouhluan and the M. kusanoi population at Kending, and even Soukar, are evolutionarily significant units for conservation programmes. [source]

The structure and status of forest fragments outside protected areas in central Uganda

AFRICAN JOURNAL OF ECOLOGY, Issue 4 2009
Deborah Baranga
Abstract Given the extent of tropical forest deforestation and as a number of conservation programmes and local communities rely on forest fragments, it has become important to understand how fragment exploitation by local communities affects forest structure and function. The effects of forest exploitation on forest structure and status of forest fragments were investigated in 20 nonreserved forest fragments in central Uganda. Enumeration of plots showed that tree species composition of the forest fragments was 60.0%, 23.7% and 6.3% for under-storey, middle and top canopy trees respectively. The major activity was fuel wood extraction (65%), followed by brick making (10%), cultivation and livestock paddocks (10%), charcoal burning (5%), local brew distillation and others (5%). These extractive processes caused drastic structural changes, habitat degradation and destruction. Tree stumps enumeration indicated that under storey trees formed the highest proportion for wood extraction. There was no significant difference in the level of forest exploitation (basal area loss) among forest patches of varying sizes. Résumé Etant donné l'étendue de la déforestation tropicale et vu qu'un certain nombre de programmes de conservation et de communautés locales dépendent de fragments forestiers, il devient vraiment important de comprendre comment l'exploitation de ces parcelles par les communautés locales affecte la structure et les fonctions forestières. Les effets de l'exploitation forestière sur la structure et le statut des fragments forestiers ont étéétudiés dans 20 fragments forestiers non préservés du centre de l'Ouganda. Le dénombrement des parcelles a montré que trois compositions d'espèces des fragments forestiers composaient respectivement 60,0%, 23,7% et 6,3% du sous-bois, de l'étage moyen et de la canopée. L'activité principale était l'extraction de bois de feu (65%), suivie par la fabrication de briques (10%), les enclos pour la culture ou le bétail (10%), la fabrication de charbon de bois (5%), la distillation de boissons locales et autres (5%). Ces diverses extractions causaient des changements structurels importants, une dégradation de l'habitat, voire sa destruction. Le dénombrement des souches d'arbres a montré que les arbres des sous-bois constituaient la plus grande proportion des arbres prélevés. Il n'y avait pas de différence significative du niveau d'exploitation forestière (perte de surface réelle) entre les îlots forestiers de tailles différentes. [source]

The purge of genetic load through restricted panmixia in a Drosophila experiment

JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 9 2010
V. ÁVILA
Abstract Using Drosophila melanogaster, we explore the consequences of restricted panmixia (RP) on the genetic load caused by segregating deleterious recessive alleles in a population where females mate a full sib with probability about ½ and mate randomly otherwise. We find that this breeding structure purges roughly half the load concealed in heterozygous condition. Furthermore, fitness did not increase after panmixia was restored, implying that, during RP, the excess of expressed load induced by inbreeding had also been efficiently purged. We find evidences for adaptation to laboratory conditions and to specific selective pressures imposed by the RP protocol. We discuss some of the consequences of these results, both for the evolution of population breeding structures and for the design of conservation programmes. [source]

Press responses to the presence of free-living Wild Boar (Sus scrofa) in southern England

MAMMAL REVIEW, Issue 4 2002
M. J. Goulding
ABSTRACT Wildlife management and conservation programmes are likely to attract media attention, especially when the programmes in question involve large mammals. The present study surveyed the response of the press (national and local newspapers, and magazines) to the existence of two populations of free-living Wild Boar (Sus scrofa) that established in southern England in the early 1990s, following the escape of animals from captivity. One-hundred and seven target articles from 46 different titles were searched for references to 18 separate issues related to topics such as agricultural damage, risk to humans and ecological impact. The presence of free-living Wild Boar in the English countryside attracted predominantly negative press coverage: the issues most frequently raised by newspaper and magazine articles were that the animals constitute a danger to the public, damage agricultural crops, predate livestock and transmit disease. A minority of articles argued that the animals should be conserved, mainly on the grounds that they could be hunted for meat. There was relatively little coverage of environmental issues, and what there was tended to focus on detrimental effects of Wild Boar on native flora and fauna. We conclude that management and conservation programmes involving large, allegedly dangerous mammals are likely to encounter an adverse press reaction. This is something that the organizers of such programmes may need to take into account when predicting public attitudes. [source]

Does a top-predator provide an endangered rodent with refuge from an invasive mesopredator?

ANIMAL CONSERVATION, Issue 4 2009
M. Letnic
Abstract In arid environments, ecological refuges are often conceptualised as places where animal species can persist through drought owing to the localised persistence of moisture and nutrients. The mesopredator release hypothesis (MRH) predicts that reduced abundance of top-order predators results in an increase in the abundance of smaller predators (mesopredators) and consequently has detrimental impacts on the prey of the smaller predators. Thus according to the MRH, the existence of larger predators may provide prey with refuge from predation. In this study, we investigated how the abundance of an endangered rodent Notomys fuscus is affected by Australia's largest predator, the dingo Canis lupus dingo, introduced mesopredators, introduced herbivores, kangaroos and rainfall. Our surveys showed that N. fuscus was more abundant where dingoes occurred. Generalised linear modelling showed that N. fuscus abundance was associated positively with dingo activity and long-term annual rainfall and negatively with red fox Vulpes vulpes activity. Our results were consistent with the hypothesis that areas with higher rainfall and dingoes provide N. fuscus with refuge from drought and predation by invasive red foxes, respectively. Top-order predators, such as dingoes, could have an important functional role in broad-scale biodiversity conservation programmes by reducing the impacts of mesopredators. [source]

Survival of very small macropod pouch young followingshort-term isolation from the pouch at various environmental temperatures

ANIMAL CONSERVATION, Issue 4 2002
David A. Taggart
There is considerable interest in the use of assisted breeding techniques as a component of conservation programmes for a variety of macropods threatened with extinction. While cross-fostering is being conducted in some programmes in captivity, little is known about the best techniques for carrying this procedure out from wild populations. In this study we compare the success of various procedures for isolating small tammar wallaby (Macropus eugenii) and brush-tailed rock wallaby (Petrogale penicillata) pouch young (0.4 g,410 g) for short periods (6 hours) as a first step towards establishing a methodology for recruiting endangered macropod pouch young directly from the wild for foster-rearing in captivity. Pouch temperature and humidity were determined. Pouch young from females in experimental groups were weighed, measured and then isolated, at 30°C, 27°C or 23°C, and 100% humidity. After isolation the weight of pouch young maintained at 30°C and 27°C had declined significantly (2,17% of body weight), whereas those held at 23°C and 100% humidity lost less than 0.5% of body weight. All young were reattached to the active teat of their mother following pouch isolation and their survival and growth monitored. Pouch young from the control group and those isolated at 23°C and 100% humidity survived and grew at normal rates. Only the largest pouch young maintained in isolation at either 30°C or 27°C survived to day 7 following reattachment. Data indicated that the proportion of weight lost by pouch young as a result of isolation decreased with increasing size and age of the pouch young. These trials indicate that it would be possible to harvest very small macropod pouch young from a species in the wild with a very high probability that they would survive short-term isolation from the pouch and reattachment to the teat. The use of this procedure in combination with cross-fostering techniques will allow small pouch young from threatened macropod species to be recruited directly from the wild into captivity, for captive breeding or to improve genetic diversity in captive colonies. It should also act to reactivate diapause embryos in these animals and hence may accelerate breeding in wild-based mothers. [source]

Objectives, criteria and methods for using molecular genetic data in priority setting for conservation of animal genetic resources

ANIMAL GENETICS, Issue 2010
P. J. Boettcher
Summary The genetic diversity of the world's livestock populations is decreasing, both within and across breeds. A wide variety of factors has contributed to the loss, replacement or genetic dilution of many local breeds. Genetic variability within the more common commercial breeds has been greatly decreased by selectively intense breeding programmes. Conservation of livestock genetic variability is thus important, especially when considering possible future changes in production environments. The world has more than 7500 livestock breeds and conservation of all of them is not feasible. Therefore, prioritization is needed. The objective of this article is to review the state of the art in approaches for prioritization of breeds for conservation, particularly those approaches that consider molecular genetic information, and to identify any shortcomings that may restrict their application. The Weitzman method was among the first and most well-known approaches for utilization of molecular genetic information in conservation prioritization. This approach balances diversity and extinction probability to yield an objective measure of conservation potential. However, this approach was designed for decision making across species and measures diversity as distinctiveness. For livestock, prioritization will most commonly be performed among breeds within species, so alternatives that measure diversity as co-ancestry (i.e. also within-breed variability) have been proposed. Although these methods are technically sound, their application has generally been limited to research studies; most existing conservation programmes have effectively primarily based decisions on extinction risk. The development of user-friendly software incorporating these approaches may increase their rate of utilization. [source]

Genetic diversity within and between European pig breeds using microsatellite markers

Conservation genetics of the endangered depressed river mussel, Pseudanodonta complanata, using amplified fragment length polymorphism (AFLP) markers

AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 5 2010
Richard Skidmore
Abstract 1.Genetic analysis is increasingly recognized as a key tool for understanding demography, and is particularly useful for describing patterns of gene flow between putative populations. Most effort has been directed towards vertebrate systems, where any one study often benefits from marker development in related species. The greater diversity of invertebrate taxa presents a challenge, but amplified fragment length polymorphism (AFLP) markers offer a solution, yielding high levels of polymorphism and no prior knowledge of a species' genome. 2.AFLP markers have been used to analyse an unusual metapopulation of an invertebrate, the endangered freshwater mussel, Pseudanodonta complanata, sampled from river systems across the UK. This was done to assess the extent to which individual river systems were genetically isolated from one another. 3.The results show patterns of weak genetic differentiation across the UK, with one hydrologically isolated population in the south west showing clear genetic differentiation from the rest of the country. However, the UK population as a whole exhibits significant isolation by distance, particularly when one population subject to fish stocking is removed, this population probably being seeded with mussel glochidia larvae which use fish as vectors. Genetic estimates of inbreeding reveal a complicated pattern in which inbreeding peaks at intermediate densities. High-density populations may be genetically diverse due to their size, while the lowest density populations may represent transient groups of emigrants from other, larger populations. 4.The findings show that limited gene flow does exist between some but not all river systems. The isolation of the south-west population indicates that dispersal is variable and should not be assumed to be present. Waterways that remain hydrologically isolated may require special attention in conservation programmes as they can harbour genetically distinct populations. The balance between river management activities and conservation priorities therefore needs careful consideration. Copyright © 2010 John Wiley & Sons, Ltd. [source]

Body size and extinction risk in Australian mammals: An information-theoretic approach

AUSTRAL ECOLOGY, Issue 6 2010
RYAN A. CHISHOLM
Abstract The critical weight range (CWR) hypothesis for Australian mammals states that extinctions and declines have been concentrated in species with body mass between 35 g and 5.5 kg. The biological basis for this hypothesis is that species of intermediate size are disproportionately impacted by introduced predators. The CWR hypothesis has received support from several statistical studies over the past decade, although the evidence is weaker or non-existent for certain groups such as mesic-zone mammals and arboreal mammals. In this study, we employ an information-theoretic model selection approach to gain further insights into the relationship between body mass and extinction risk in Australian mammals. We find evidence, consistent with the CWR hypothesis, that extinction risk peaks at intermediate body masses for marsupials, rodents and ground-dwelling species, but not for arboreal species. In contrast to previous studies, we find that the CWR describes extinction patterns in the mesic zone as well as the arid zone. In the mesic zone, there is also a weaker tendency for large species above the CWR to be more vulnerable, consistent with extinction patterns on other continents. We find that a more biological plausible Gaussian distribution consistently fits the data better than the polynomial models that have been used in previous studies. Our results justify conservation programmes targeted at species within the CWR across Australia. [source]