| 1. |
- Hansson, L-A, et al.
(author)
-
A synthesis of animal movement across scales
- 2014
-
In: Animal Movement Across Scales. - : Oxford University Press. - 9780199677184 ; , s. 259-267
-
Book chapter (peer-reviewed)abstract
- This chapter aims at synthesizing the knowledge presented in the chapters of the book’s three sections by addressing evolutionary compromises, dispersal, gene flow, and assisted movements. How climate change and other environmental changes at different scales may affect animal movement, migration, and dispersal in the future are also summarized here. Moreover, how the different senses are utilized for navigation and orientation and how these may lead to different movement and migration patterns are also discussed. Finally, how the recent technical revolution has affected animal movement research is addressed and the view on future perspectives of animal movement research is also provided.
|
|
| 2. |
- Chapman, Ben B, et al.
(author)
-
Patterns of Animal Migration
- 2014
-
In: Animal movement across scales. - : Oxford University Press. - 9780199677184 ; , s. 11-35
-
Book chapter (peer-reviewed)
|
|
| 3. |
|
|
| 4. |
- Ahlgren, Johan, et al.
(author)
-
Camouflaged or tanned: plasticity in freshwater snail pigmentation.
- 2013
-
In: Biology letters. - : The Royal Society. - 1744-9561 .- 1744-957X. ; 9:5, s. 4-20130464
-
Journal article (peer-reviewed)abstract
- By having phenotypically plastic traits, many organisms optimize their fitness in response to fluctuating threats. Freshwater snails with translucent shells, e.g. snails from the Radix genus, differ considerably in their mantle pigmentation patterns, with snails from the same water body ranging from being completely dark pigmented to having only a few dark patterns. These pigmentation differences have previously been suggested to be genetically fixed, but we propose that this polymorphism is owing to phenotypic plasticity in response to a fluctuating environment. Hence, we here aimed to assess whether common stressors, including ultraviolet radiation (UVR) and predation, induce a plastic response in mantle pigmentation patterns of Radix balthica. We show, in contrast to previous studies, that snails are plastic in their expression of mantle pigmentation in response to changes in UVR and predator threats, i.e. differences among populations are not genetically fixed. When exposed to cues from visually hunting fish, R. balthica increased the proportion of their dark pigmentation, suggesting a crypsis strategy. Snails increased their pigmentation even further in response to UVR, but this also led to a reduction in pattern complexity. Furthermore, when exposed to UVR and fish simultaneously, snails responded in the same way as in the UVR treatment, suggesting a trade-off between photoprotection and crypsis.
|
|
| 5. |
- Albrectsen, Benedicte R., et al.
(author)
-
The diversity and identification of eulophid parasitic wasps (Hymenoptera: Chalcidoidea: Eulophidae) on Phyllocnistis labyrinthella (Lepidoptera: Gracillariidae) from Västerbotten, Sweden.
- 2012
-
In: Entomologisk tidskrift. - 0013-886X. ; 133:3, s. 111-118
-
Journal article (peer-reviewed)abstract
- Caterpillars of the mining micro-moth Phyllocnistis labyrinthella feed on leaves of aspen (Populus tremula) and are often parasitized by eulophid wasps. The parasitoids are a potential important cause of death for the miners. During 2009-2011 we collected mined leaves from an experimental stand of aspen trees in Västerbotten. Adults emerged from 17-35 percent of the mines and of these every second to third specimen appeared as wasps. These wasps represented seven species of eulophid parasitoids of which three were new to Västerbotten: Chrysocharis nitetis (Walker), Cirrospilus diallus (Walker) and Cirrospilus pictus (Nees). We include an identification key that may be used to identify these eulophid species.
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Brodersen, Jakob, et al.
(author)
-
Variable individual consistency in timing and destination of winter migrating fish
- 2012
-
In: Biology Letters. - : The Royal Society. - 1744-9561 .- 1744-957X. ; 8, s. 21-23
-
Journal article (peer-reviewed)abstract
- Migration is an important event in the life history of many animals, but there is considerable variation within populations in the timing and final destination. Such differential migration at the population level can be strongly determined by individuals showing different consistencies in migratory traits. By tagging individual cyprinid fish with uniquely coded electronic tags, and recording their winter migrations from lakes to streams for 6 consecutive years, we obtained highly detailed long-term information on the differential migration patterns of individuals. We found that individual migrants showed consistent site fidelities for over-wintering streams over multiple migratory seasons and that they were also consistent in their seasonal timing of migration. Our data also suggest that consistency itself can be considered as an individual trait, with migrants that exhibit consistent site fidelity also showing consistency in migratory timing. The finding of a mixture of both consistent and inconsistent individuals within a population furthers our understanding of intrapopulation variability in migration strategies, and we hypothesize that environmental variation can maintain such different strategies.
|
|
| 10. |
- Brönmark, Christer, et al.
(author)
-
Regime shifts in shallow lakes: the importance of seasonal fish migration
- 2010
-
In: Hydrobiologia. - : Springer Science and Business Media LLC. - 0018-8158 .- 1573-5117. ; 646:1, s. 91-100
-
Conference paper (peer-reviewed)abstract
- Shallow eutrophic lakes commonly exist in two alternative stable states: a clear-water state and a turbid water state. A number of mechanisms, including both abiotic and biotic processes, buffer the respective states against changes, whereas other mechanisms likely drive transitions between states. Our earlier research shows that a large proportion of zooplanktivorous fish populations in shallow lakes undertake seasonal migrations where they leave the lake during winter and migrate back to the lake in spring. Based on our past research, we propose a number of scenarios of how feedback processes between the individual and ecosystem levels may affect stability of alternative stable states in shallow lakes when mediated by fish migration. Migration effects on shallow lakes result from processes at different scales, from the individual to the ecosystem. Our earlier research has shown that ecosystem properties, including piscivore abundance and zooplankton productivity, affect the individual state of zooplanktivorous fish, such as growth rate or condition. Individual state, in turn, affects the relative proportion and timing of migrating zooplanktivorous fish. This change, in turn, may stabilize states or cause runaway processes that eventually lead to state shifts. Consequently, such knowledge of processes coupled to seasonal migration of planktivorous fish should increase our understanding of shallow lake dynamics.
|
|
