20 research outputs found

    A Visual Assessment Scale for Rapid Evaluation of Mangrove Degradation, Using Examples from Myanmar and Madagascar

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    Mangroves are globally threatened, disappearing and degraded. They are lost due to land use changes, mostly agricultural expansion and aquaculture, but also degraded by cutting by villagers and logging and timber extraction for domestic and economic purposes. Extent and conversion of mangroves can usually be estimated by applying remote sensing and modern drone technology, but the scale of degradation of mangrove habitats is not easily detected by such methods. In this paper we propose an assessment tool for a rapid evaluation on the degradation, using examples from different regions in Myanmar and Madagascar. We propose a visual and practical guide listing a range of 1–6 to identify and quantify the level of degradation. We demonstrate the application by displaying various examples from Myanmar and Madagascar and how this tool can be used for wider applications, discussing advantages scope, and limitations

    Antiprädationsverhalten von Weißwangengänsen auf Kolguyev und Svalbard

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    Auch in den arktischen Brutgebieten sind Wildgänse und ihre Brut durch Fressfeinde wie den Eisfuchs (Alopex lagopus) oder die Eismöwe (Larus hyperboreus) gefährdet. In diesem Bericht wird am Beispiel von Weißwangengänsen (Branta leucopsis) das Verhalten der Vermeidung von Prädation auf Svalbard mit dem der auf Kolguyev brütenden Artgenossen untersucht. Die Unterschiede und Gemeinsamkeiten werden diskutiert.On the breeding grounds geese and their broods are threatened by predators like polar foxes (Alopex lagopus) or Glacous Gulls (Larus hyperboreus). In this review we compare antipredation behaviour of breeding and broad rearing Barnacle Geese (Branta leucopsis) on Svalbard and Kolguev. Similarities and differences are presented and discussed

    REGISTRO DE ACTIVIDAD REPRODUCTIVA DE CHARADRIUS VOCIFERUS (LINNAEUS 1758, CHORLO GRITÓN) EN EL HUMEDAL DE PARAÍSO, HUACHO (LIMA – PERÚ)

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    We report the record of a Charadrius vociferus (Charadriiformes: Charadriidae; killdeer) nest in Paraíso wetland located in Huacho (Lima – Peru) (11°12'54"S, 77°35'16"W), containing four eggs, one of which was in the process of hatching.Se reporta el registro de un nido de Charadrius vociferus (Charadriiformes: Charadriidae; chorlo gritón) en el humedal Paraíso ubicado en Huacho (Lima – Perú) (11°12'54"S, 77°35'16"O), conteniendo cuatro huevos, uno de los cuales se encontraba en proceso de eclosión

    Birds and Mammals of the Lena Delta Nature Reserve, Siberia

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    The Lena Delta is the largest arctic delta covered entirely by tundra. Protected since 1986, it is one of the richest areas in the Arctic north of 71° N for both species diversity and breeding densities. Between 6 June and 17 August 1997, 16 mammal species and 76 bird species were recorded in the Lena Delta Nature Reserve and the surrounding buffer zone. Several species are new to the region: far-eastern curlew, fieldfare, redwing, arctic warbler, red-breasted flycatcher, and common rat. New breeders are merlin and arctic warbler. These 1997 records, combined with those from earlier studies, give a total of 122 bird species for the region. Of these, 67 have been found breeding at least once. Densities ranging from 245 to 641 birds per km² were recorded in two restricted study areas. Such densities are unusually high north of 70° N for non-colonial breeding birds. Lapland longspur (100-300 individuals/km²), red phalarope (up to 200 ind./km²), and several Calidris species were the most common. Ruddy turnstone and dunlin had densities higher than those previously reported from the Lena Delta and other Siberian sites. Among the shorebirds, spotted redshank, pintail snipe, grey plover, dunlin, and curlew sandpiper may have extended their breeding range or increased in population during the last 15 years. But further evidence is still needed to confirm the westward extension of spectacled eider, long-billed dowitcher, and sharp-tailed sandpiper.Le delta de la Lena est le plus grand delta arctique totalement recouvert de toundra. Protégé depuis 1986, il est l'une des zones les plus riches de l'Arctique au nord du 71° de latitude N., tant par la richesse spécifique que par les densités d'oiseaux nicheurs. Seize espèces de mammifères et 76 espèces d'oiseaux ont été observées dans la Réserve naturelle du delta de la Lena et sa zone périphérique entre le 6 juin et le 17 août 1997. Plusieurs espèces sont nouvelles pour la région: courlis de Sibérie, grive litorne, grive mauvis, pouillot boréal, gobemouche nain et rat surmulot. Les nouvelles espèces nicheuses sont le faucon émerillon et le pouillot boréal. Combinés à ceux d'études plus anciennes, nos résultats portent à 122 le nombre total d'espèces d'oiseaux recensés dans cette région et à 67 celui des espèces s'y étant reproduit au moins une fois. Des densités comprises entre 245 et 641 individus au km² ont été trouvées sur deux zones d'étude restreintes, densités exceptionnelles au nord du 70° de latitude N. pour des espèces non coloniales. Les espèces les mieux représentées sont le bruant lapon (100-300 ind./km²), le phalarope à bec large (jusqu'à 200 ind./km²) et plusieurs espèces de Calidris. Le tournepierre à collier et le bécasseau variable avaient des densités plus fortes que celles précédemment rapportées pour le delta de la Lena et d'autres sites sibériens. Le chevalier arlequin, la bécassine à queue pointue, le pluvier argenté, le bécasseau variable et le bécasseau cocorli font partie des limicoles qui semblent avoir étendu leur aire de distribution ou augmenté leur population durant les 15 dernières années, mais d'autres travaux seront nécessaires avant de confirmer l'extension occidentale de l'eider à lunettes, du limnodrome à long bec et du bécasseau à queue pointue

    CAFF CBMP Report No. 20 - Arctic Species Trend Index 2010: Tracking Trends in Arctic Wildlife.

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    The contribution of Arctic wildlife to global biodiversity is substantial. The region supports globally significant populations of birds, mammals and fish.In this report, vertebrate population-abundance data were used to produce an indicator of the trends in Arctic biodiversity over the past 34 years (1970 as the baseline1). This index tracks 965 populations of 306 species, representing 35% of all known vertebrate species found in the Arctic. These observed trends are largely consistent with current predictions regarding the response of Arctic wildlife to climate change and expected increases in previously over-harvested species, and suggest that human-induced changes in Arctic ecosystems are already resulting in winners and losers

    Responses to projected changes in climate and UV-B at the species level

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    Environmental manipulation experiments showed that species respond individualistically to each environmental-change variable. The greatest responses of plants were generally to nutrient, particularly nitrogen, addition. Summer warming experiments showed that woody plant responses were dominant and that mosses and lichens became less abundant. Responses to warming were controlled by moisture availability and snow cover. Many invertebrates increased population growth in response to summer warming, as long as desiccation was not induced. CO2 and UV-B enrichment experiments showed that plant and animal responses were small. However, some microorganisms and species of fungi were sensitive to increased UV-B and some intensive mutagenic actions could, perhaps, lead to unexpected epidemic outbreaks. Tundra soil heating, CO 2 enrichment and amendment with mineral nutrients generally accelerated microbial activity. Algae are likely to dominate cyanobacteria in milder climates. Expected increases in winter freeze-thaw cycles leading to ice-crust formation are likely to severely reduce winter survival rate and disrupt the population dynamics of many terrestrial animals. A deeper snow cover is likely to restrict access to winter pastures by reindeer/caribou and their ability to flee from predators while any earlier onset of the snow-free period is likely to stimulate increased plant growth. Initial species responses to climate change might occur at the sub-species level: an Arctic plant or animal species with high genetic/racial diversity has proved an ability to adapt to different environmental conditions in the past and is likely to do so also in the future. Indigenous knowledge, air photographs, satellite images and monitoring show that changes in the distributions of some species are already occurring: Arctic vegetation is becoming more shrubby and more productive, there have been recent changes in the ranges of caribou, and "new" species of insects and birds previously associated with areas south of the treeline have been recorded. In contrast, almost all Arctic breeding bird species are declining and models predict further quite dramatic reductions of the populations of tundra birds due to warming. Species-climate response surface models predict potential future ranges of current Arctic species that are often markedly reduced and displaced northwards in response to warming. In contrast, invertebrates and microorganisms are very likely to quickly expand their ranges northwards into the Arctic
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