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- Mills, James A., et al.
(författare)
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Archiving Primary Data : Solutions for Long-Term Studies
- 2015
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Ingår i: Trends in Ecology & Evolution. - : Elsevier BV. - 0169-5347 .- 1872-8383. ; 30:10, s. 581-589
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Tidskriftsartikel (refereegranskat)abstract
- The recent trend for journals to require open access to primary data included in publications has been embraced by many biologists, but has caused apprehension amongst researchers engaged in long-term ecological and evolutionary studies. A worldwide survey of 73 principal investigators (PIs) with long-term studies revealed positive attitudes towards sharing data with the agreement or involvement of the PI, and 93% of PIs have historically shared data. Only 8% were in favor of uncontrolled, open access to primary data while 63% expressed serious concern. We present here their viewpoint on an issue that can have non-trivial scientific consequences. We discuss potential costs of public data archiving and provide possible solutions to meet the needs of journals and researchers.
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| 2. |
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| 3. |
- Cross, Adam D. P., et al.
(författare)
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Isotopic analysis of island House Martins Delichon urbica indicates marine provenance of nutrients
- 2014
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Ingår i: Ibis. - : Wiley. - 0019-1019 .- 1474-919X. ; 156:3, s. 676-681
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Tidskriftsartikel (refereegranskat)abstract
- The presence of one of the largest colonies of House Martins in Europe on the small island of Stora Karlso, Sweden, led us to investigate the source of their food by analysis of stable isotopes of carbon and nitrogen. Carbon isotopic values of House Martin nestlings were the same as those of Common Guillemot Uria aalge nestlings fed on marine fish, but differed from local Collared Flycatcher Ficedula albicollis nestlings fed on woodland insects. We infer that these House Martins fed their chicks almost exclusively on insects that had used nutrients derived from seabirds, indicating a dependence on the presence of a large seabird colony. We suggest by extension that some populations of island passerines of high conservation importance may also be dependent on nutrient subsidies from seabird colonies.
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| 4. |
- Österblom, Henrik, 1973-
(författare)
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Complexity and Change in a Simple Food Web : Studies in the Baltic Sea (FAO Area 27.IIId)
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- An influence at one trophic level can result in dynamic impacts also on other components of a food web. These dynamics are known as trophic cascades, and can be both top-down and bottom-up. After a near-collapse of the Baltic cod Gadus morhua stock in the 1980s, its main prey sprat Sprattus sprattus increased dramatically. The main food of sprat, marine copepods, decreased during the same time period, likely a combined effect of increased predation pressure from sprat and decreasing salinities. This shortage of food for sprat resulted in decreasing quality of sprat as a food source for common guillemots Uria aalge. However, a recent increase in fishing for sprat has again resulted in better feeding conditions for guillemots.Human impacts on this simple food web can be complex. In the early 20th century, marine mammals were abundant and nutrient levels were low in the Baltic Sea. This thesis illustrate that this situation corresponded to lower fish biomass. A reduction of seals early in the century led to reduced top-down control, which resulted in increasing fish stocks. Later, in the 1950s, the largest inflow of salt water during the century mobilized accumulated phosphorus from the deep sediments, which stimulated nitrogen fixation. Combined with increasing anthropogenic nutrient loads, this led to increased primary production and a rapid change from an oligotrophic to a eutrophicated state. This change can be termed a regime shift, which also stimulated fish production. Subsequent over-fishing of cod likely caused a second regime shift, from a cod- to a clupeid- dominated state, which led to the described effects on the common guillemots.Several factors affect the life-history of this long-lived seabird. Bycatches in gillnet fisheries is one factor directly affecting guillemot survival, and the proportion of bycatches increased during a period of increasing fishing effort. Surprisingly, avian cholera, a previously undocumented disease in common guillemots, was found at times to cause considerable adult mortality. Common guillemot life-history information can communicate the diversity of factors influencing marine ecosystems – hopefully this can increase our understanding of how complex even "simple" food webs are.
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