Sökning: "declining species"

Visar resultat 1 - 5 av 66 uppsatser innehållade orden declining species.

  1. 1. The introduction of the Africanised honey bee: A stinging menace or a blessing of the Americas? : a comparison of the Brazilian and USA beekeeping experiences

    Master-uppsats, SLU/Dept. of Urban and Rural Development

    Författare :Jorge Antonio Moreno Reategui; [2020]
    Nyckelord :Beekeeping Social field; Africanised honey bee; qualitative and quantitative research methodology;

    Sammanfattning : In 1956, Brazilian scientist Warwick Estevam Kerr, introduced queens of the African honey bee (AHB) from South Africa to breed with European honey bees (EHB) in order to improve honey production in Brazil. Some of the AHB swarmed by accident out of the experimental apiary, located in Rio Claro-São Paulo State, and started to spread. LÄS MER

  2. 2. Bumblebee resource dynamics : a review of foraging and nesting in the agricultural landscape

    Kandidat-uppsats, SLU/Dept. of Ecology

    Författare :Anna Douhan Sundahl; [2020]
    Nyckelord :bumblebees; bumblebee population dynamics; bumblebee drivers; flower strips; competition with honeybees; foraging; nesting; hibernation;

    Sammanfattning : 90 % of all plants on earth either benefits or entirely depends on pollination. There are pollinators among families of bees (Apidea), butterflies (Lepidoptera) and birds (Aves). Bees of genus Bombus spp., bumblebees, are especially important and provide pollination service for 80 % of the crops of Europe and many wild plant species. LÄS MER

  3. 3. Laken i vänern – Populationsutveckling och potentiella påverkansfaktorer : Jämförande analyser av material från perioden 1973-2018

    Kandidat-uppsats, Högskolan i Skövde/Institutionen för biovetenskap

    Författare :Hannes Byström Mollstedt; [2019]
    Nyckelord :Lake; Vänern; Fisk;

    Sammanfattning : The burbot (Lota lota, Linnaeus 1758) is a benthic and predatory cod-relative that only occurs in fresh- and brackish water around the northern hemisphere. It has long been a common catch in Swedish lakes and rivers, but the species has seen a decline by over 20% since the mid 1980’s. LÄS MER

  4. 4. Analyzing Factors Influencing Reproductive Success of the Mountain Chicken : Nordens Ark Captive Breeding Program

    Kandidat-uppsats, Högskolan i Skövde/Institutionen för biovetenskap

    Författare :Chad Donaldson; [2019]
    Nyckelord :frog; frogs; mountain chicken; mountain chicken frog; leptodactylus; fallax; herpetology; amphibian; amphibians; multiple linear regression; statistical analysis; Nordens Ark; captive breeding; zoo; zoology; conservation; endangered species; grodor; groda; kycklinggroda; Nordens Ark; amfibier; zoologi; herpetologi; analys; hotade arter; bevarande; avel;

    Sammanfattning : Amphibians globally are declining with roughly a third facing extinction due primarily to threats linked to human impacts. One way in which this is being combated is by captive breeding programs. LÄS MER

  5. 5. The declining significance of seagrass-associated invertebrate gleaning for providing food security in Kaole, Tanzania

    Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

    Författare :Johanna Lauritsen; [2019]
    Nyckelord :Sustainable Development; food security; seagrass; small-scale fishery; invertebrates; Tanzania;

    Sammanfattning : This thesis applies the food security concept to assess the significance of seagrass-associated invertebrate gleaning for providing food security in Kaole, Tanzania. It assesses the availability, accessibility, utilisation and stability over time of this food source. To explore this, a multi-strategy research design was used. LÄS MER