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Author Rodrí­guez, A.; Rodrí­guez, B.; Lucas, M.P.
Title Trends in numbers of petrels attracted to artificial lights suggest population declines in Tenerife, Canary Islands Type Journal Article
Year 2012 Publication Ibis Abbreviated Journal (up)
Volume 154 Issue 1 Pages 167-172
Keywords Animals; birds; petrels; Cory's shearwater; Calonectris diomedea; Bulwer's Petrel; Bulweria bulwerii; Macaronesian Shearwater; Puffinus baroli; reproductive strategies
Abstract The secretive breeding behaviour of petrels makes monitoring their breeding populations challenging. To assess population trends of Cory's Shearwater Calonectris diomedea, Bulwer's Petrel Bulweria bulwerii and Macaronesian Shearwater Puffinus baroli in Tenerife from 1990 to 2010, we used data from rescue campaigns that aim to reduce the mortality of fledgling petrels attracted to artificial lights as proxies for trends in breeding population size. Despite increases in human population size and light pollution, the number of rescued fledglings of Cory's Shearwater and Bulwer's Petrel increased and remained stable, respectively, whereas numbers of rescued Macaronesian Shearwaters sharply declined. In the absence of more accurate population estimates, these results suggest a worrying decline in the Macaronesian Shearwater's breeding population.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0019-1019 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 38
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Author Baker, G.C.; Dekker, R.W.R.J.
Title Lunar synchrony in the reproduction of the Moluccan Megapode Megapodius wallacei Type Journal Article
Year 2000 Publication Ibis Abbreviated Journal (up)
Volume 142 Issue 3 Pages 382-388
Keywords Moluccan Megapode; Megapodius wallacei; birds; nesting; reproduction; animals; *Moon
Abstract The Moluccan Megapode Megapodius wallacei uses heat generated by the sun to incubate its eggs. It buries the eggs deep in the sand of sun-exposed beaches and open sandy areas on islands in the Moluccas, Indonesia. The eggs are laid at night and left to incubate for two to three months without parental care. We present evidence that the Moluccan Megapode exhibits lunar synchrony in the timing of egg-laying, its spatial distribution of egg burrows and in its behaviour at communal nesting grounds. More Moluccan Megapodes visit the nesting grounds on bright nights than during the new moon. Data collected on the spatial distribution and depth of egg burrows also exhibit lunar periodicity. On moonlit nights, the birds excavate burrows in communal groups and spend longer at the nesting ground digging deeper burrows. Lunaphilia and lunar periodicity of reproduction are rarely documented in birds. We discuss possible explanations for these behaviours in the Moluccan Megapode.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0019-1019 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 52
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Author Mehner, T.
Title Diel vertical migration of freshwater fishes – proximate triggers, ultimate causes and research perspectives: Diel vertical migration in freshwater fishes Type Journal Article
Year 2012 Publication Freshwater Biology Abbreviated Journal (up)
Volume 57 Issue 7 Pages 1342-1359
Keywords diel vertical migration; *Fishes; freshwater fish
Abstract 1. Diel vertical migrations (DVM) are typical for many cold-water fish species such as Pacific salmons (Oncorhynchus spp.) and coregonids (Coregonus spp.) inhabiting deep lakes. A comprehensive recent overview of DVM in freshwater fish has not been available, however.

2. The main proximate trigger of DVM in freshwater fish is the diel change in light intensity, with declining illumination at dusk triggering the ascent and the increase at dawn triggering the descent. Additional proximate cues are hydrostatic pressure and water temperature, which may guide fish into particular water layers at night.

3. Ultimate causes of DVM encompass bioenergetics efficiency, feeding opportunities and predator avoidance. None of these factors alone can explain the DVM in all cases. Multi-factorial hypotheses, such as the ‘antipredation window’ combined with the thermal niche hypothesis, are more likely to explain DVM. It is suggested that planktivorous fish move within a layer sufficiently well illuminated to capture zooplankton, but too dark for predators to feed upon the migrating fish. In complete darkness, fish seek layers with a temperature that optimises bioenergetics efficiency. The strength of each factor may differ from lake to lake, and hence system-specific individual analyses are needed.

4. Mechanistic details that are still poorly explored are the costs of buoyancy regulation and migration, the critical light thresholds for feeding of planktivorous and piscivorous fish, and predator assessment by (and size-dependent predation risk of) the prey fish.

5. A comprehensive understanding of the adaptive value of DVM can be attained only if the behaviour of individual fish within migrating populations is explicitly taken into account. Size, condition and reproductive value differ between individuals, suggesting that migrating populations should split into migrants and non-migrants for whom the balance between mortality risk and growth rate can differ. There is increasing evidence for this type of partial DVM within populations.

6. Whereas patterns of DVM are well documented, the evolution of DVM is still only poorly understood. Because experimental approaches at realistic natural scales remain difficult, a combination of comprehensive data sets with modelling is likely to resolve the relative importance of different proximate and ultimate causes behind DVM in fish.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0046-5070 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 66
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Author Polak, T.; Korine, C.; Yair, S.; Holderied, M.W.
Title Differential effects of artificial lighting on flight and foraging behaviour of two sympatric bat species in a desert: Light pollution in deserts and bat foraging Type Journal Article
Year 2011 Publication Journal of Zoology Abbreviated Journal (up)
Volume 285 Issue 1 Pages 21-27
Keywords ight pollution; desert bats; Eptesicus bottae; flight behaviour; Pipistrellus kuhlii; animals; mammals; bats
Abstract Human habitation in deserts can create rich novel resources that may be used by native desert species. However, at night such resources may lose attractiveness when they are in artificially lit areas. For bats, attraction to such manmade habitats might be species specific. In an isolated village in the Negev desert that is known for its high bat activity we investigated the effects of artificial lighting on flight behaviour of two aerial insectivorous bat species: Pipistrellus kuhlii, a non-desert synanthropic bat, common in urban environments and Eptesicus bottae, a desert-dwelling species. Using an acoustic tracking system we reconstructed flight trajectories for bats that flew under artificial lights [Light treatment (L)] versus in natural darkness [Dark treatment (D)]. Under L both P. kuhlii and E. bottae flew significantly faster than under D. Under L, P. kuhlii also flew at significantly lower altitude (i.e. away from a floodlight) than under D. Whereas P. kuhlii foraged both in L and D, E. bottae only foraged in D. In L, activity of E. bottae decreased and it merely transited the illuminated area at commuting rather than foraging speed. Thus, under artificially lighted conditions the non-desert synanthropic species may have a competitive advantage over the native desert species and may outcompete it for aerial insect prey. Controlling light pollution in deserts and keeping important foraging sites unlit may reduce the synanthropic species' competitive advantage over native desert bats.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0952-8369 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 99
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Author Bramm, M.E.; Lassen, M.K.; Liboriussen, L.; Richardson, K.; Ventura, M.; Jeppesen, E.
Title The role of light for fish-zooplankton-phytoplankton interactions during winter in shallow lakes – a climate change perspective Type Journal Article
Year 2009 Publication Freshwater Biology Abbreviated Journal (up)
Volume 54 Issue 5 Pages 1093-1109
Keywords ood availability; global warming; light manipulation; zooplanktivorous fish; zooplankton community structure
Abstract 1. Variations in the light regime can affect the availability and quality of food for zooplankton grazers as well as their exposure to fish predation. In northern lakes light is particularly low in winter and, with increasing warming, the northern limit of some present-day plankton communities may move further north and the plankton will thus receive less winter light.

2.&#8194;We followed the changes in the biomass and community structure of zooplankton and phytoplankton in a clear and a turbid shallow lake during winter (November–March) in enclosures both with and without fish and with four different light treatments (100%, 55%, 7% and <1% of incoming light).

3.&#8194;In both lakes total zooplankton biomass and chlorophyll-a were influenced by light availability and the presence of fish. Presence of fish irrespective of the light level led to low crustacean biomass, high rotifer biomass and changes in the life history of copepods. The strength of the fish effect on zooplankton biomass diminished with declining light and the effect of light was strongest in the presence of fish.

4.&#8194;When fish were present, reduced light led to a shift from rotifers to calanoid copepods in the clear lake and from rotifers to cyclopoid copepods in the turbid lake. Light affected the phytoplankton biomass and, to a lesser extent, the phytoplankton community composition and size. However, the fish effect on phytoplankton was overall weak.

5.&#8194;Our results from typical Danish shallow eutrophic lakes suggest that major changes in winter light conditions are needed in order to have a significant effect on the plankton community. The change in light occurring when such plankton communities move northwards in response to global warming will mostly be of modest importance for this lake type, at least for the rest of this century in an IPCC A2 scenario, while stronger effects may be observed in deep lakes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0046-5070 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 106
Permanent link to this record