Search for dissertations about: "FISH PREDATION"

Showing result 1 - 5 of 84 swedish dissertations containing the words FISH PREDATION.

2. 1. Direct and indirect effects of fish predation and excretion in aquatic food webs

   Author : José Luiz Attayde; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; marine biology; Hydrobiology; zooplankton; resilience; predation; phytoplankton; nutrient enrichment; nutrient recycling; interaction strength; herbivory; food webs; food chain; excretion; fish; detritus; detritivory; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi;

   Abstract : The aim of this thesis was to elucidate the mechanisms by which planktivorous fish can affect planktonic communities in lakes and how they may affect benthic communities through their effects on planktonic communities. In a laboratory experiment, nutrients released by fish increased algal biomass and altered phytoplankton community structure, suggesting that fish can affect phytoplankton by directly releasing nutrients. READ MORE

4. 2. Waterfowl in temperate eutrophic lakes - Interactions with macroinvertebrates, submerged vegetation and fish

   Author : Ola Marklund; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Hydrobiology; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Chara; Asellus; chironomidae; ultraviolet radiation; epiphytes; predation; herbivory; diel vertical migration; fish; Waterfowl; macroinvertebrates; submerged vegetation;

   Abstract : The aim of this thesis was to explore some of the important links between waterfowl and the biota in shallow eutrophic lakes in temperate areas. Waterfowl depend on macroinvertebrates as sources of protein and calcium, which are essential for egg production and growth. Macroinvertebrates in turn depend on submerged vegetation for food and shelter. READ MORE

5. 3. Predation as a driver of reproductive isolation - from adaptive divergence to hybrid inviability

   Author : Varpu Pärssinen; Enhet akvatisk ekologi; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; reproductive isolation; ecological speciation; predation; adaptive radiation; evolution; behaviour; fish;

   Abstract : Natural selection can play an important role in the origin of new species. When reproductive isolation evolves as a result of ecologically-based divergent natural selection, the process is referred to as ecological speciation. In most organisms, sufficient reproductive isolation is considered to be essential for the establishment of new species. READ MORE

6. 4. Assembly of Gut Microbial Communities in Freshwater Fish and Their Roles in Fish Condition

   Author : Yinghua Zha; Richard Svanbäck; Eva Lindström; Peter Eklöv; Brendan Bohannan; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; freshwater fish; gut microbial communities; predation stress; diet; fish condition; bacterial colonization; metacommunity theory; dispersal; Biology with specialization in Limnology; Biologi med inriktning mot limnologi;

   Abstract : Animal hosts provide associated microorganisms with suitable ecological niches in their intestines. Microbes help their hosts to digest food, protect against pathogens, and influence the host’s metabolisms. Compositional variation of gut microbial communities is common among hosts, and may affect the health status of hosts. READ MORE

7. 5. Why and how brain size evolves : Sociality, predation and allometry

   Author : Wouter van der Bijl; Niclas Kolm; Joah Madden; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; brain size; brain size evolution; encephalization; predation; predator inspection; sociality; animal contest; constraint; etologi; Ethology;

   Abstract : The evolution of the vertebrate brain has remained a topic of intense interest from biologists over many decades. Evolutionary biologists have seen it as an intriguing example of how the size and structure of a trait evolves across large phylogenies and under body size constraints, with both large shifts in deep evolutionary time and continuous smaller scale adaptation. READ MORE