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1.
Low light inhibits native fish movement through a vertical‐slot fishway: Implications for engineering design 下载免费PDF全文
M. J. Jones L. J. Baumgartner B. P. Zampatti K. Beyer 《Fisheries Management and Ecology》2017,24(3):177-185
Light intensity within a vertical‐slot fishway was manipulated to determine the effect on fish movement. Three treatments (darkness, low light, artificial light) were tested with natural daylight used as a control. Light intensity varied from 0 to 1,692 lux for the three treatments and from 1 to 4,550 lux for the control. Light intensity outside the fishway ranged from 31 to 80 900 lux. A total of 64 385 fish were collected from six species. The abundance of Australian smelt Retropinna semoni (Webber), unspecked hardyhead Craterocephalus stercusmuscarum fulvus Ivantsoff, Crowley and Allen, bony herring Nematalosa erebi (Günther), carp gudgeon Hypseleotris spp. and Eastern gambusia Gambusia holbrooki (Girard) moving upstream reduced significantly under low‐light conditions. Conversely, movement of macroinvertebrates (freshwater shrimp Macrobrachium australiense Holthuis and freshwater prawn Paratya australiensis Kemp) increased at low‐light intensities. The number of fish moving under artificial light (28 617) was similar to that under natural daylight (33 919). Movements of Australian freshwater fish and macroinvertebrates were found to be influenced by changes in light intensity. Instream structures that alter light conditions, such as road culverts, may thus act as behavioural barriers to fish movement, and this could be mitigated by the provision of natural or artificial light. 相似文献
2.
Michelle D. Staudinger Katherine E. Mills Karen Stamieszkin Nicholas R. Record Christine A. Hudak Andrew Allyn Antony Diamond Kevin D. Friedland Walt Golet Meghan Elisabeth Henderson Christina M. Hernandez Thomas G. Huntington Rubao Ji Catherine L. Johnson David Samuel Johnson Adrian Jordaan John Kocik Yun Li Matthew Liebman Owen C. Nichols Daniel Pendleton R. Anne Richards Thomas Robben Andrew C. Thomas Harvey J. Walsh Keenan Yakola 《Fisheries Oceanography》2019,28(5):532-566
The timing of recurring biological and seasonal environmental events is changing on a global scale relative to temperature and other climate drivers. This study considers the Gulf of Maine ecosystem, a region of high social and ecological importance in the Northwest Atlantic Ocean and synthesizes current knowledge of (a) key seasonal processes, patterns, and events; (b) direct evidence for shifts in timing; (c) implications of phenological responses for linked ecological‐human systems; and (d) potential phenology‐focused adaptation strategies and actions. Twenty studies demonstrated shifts in timing of regional marine organisms and seasonal environmental events. The most common response was earlier timing, observed in spring onset, spring and winter hydrology, zooplankton abundance, occurrence of several larval fishes, and diadromous fish migrations. Later timing was documented for fall onset, reproduction and fledging in Atlantic puffins, spring and fall phytoplankton blooms, and occurrence of additional larval fishes. Changes in event duration generally increased and were detected in zooplankton peak abundance, early life history periods of macro‐invertebrates, and lobster fishery landings. Reduced duration was observed in winter–spring ice‐affected stream flows. Two studies projected phenological changes, both finding diapause duration would decrease in zooplankton under future climate scenarios. Phenological responses were species‐specific and varied depending on the environmental driver, spatial, and temporal scales evaluated. Overall, a wide range of baseline phenology and relevant modeling studies exist, yet surprisingly few document long‐term shifts. Results reveal a need for increased emphasis on phenological shifts in the Gulf of Maine and identify opportunities for future research and consideration of phenological changes in adaptation efforts. 相似文献
3.
Water competition in overallocated rivers is often extreme, and climate change exacerbates the challenge of balancing ecosystem and societal water needs. During a severe California drought in 2013–2014, storage in a strategic reservoir dropped to critically low levels, necessitating reduced downstream discharge during Chinook salmon, Oncorhynchus tshawytscha (Walbaum), incubation and rearing. In response, stakeholders developed an adaptive management process to balance competing water needs, including reservoir storage and salmon survival. This approach incorporated decision tree models, integrating salmon life stage transitions to define potential impacts. Life stage‐specific thresholds were identified and monitored to determine management triggers and actions. Flow reduction stranded up to 12% of incubating embryos and thus was used to trigger a flow pulse. Frequency of stranded fry in redds was reduced post‐pulse. Water quality did not change but remained within the species’ tolerance. High densities, poor body condition and aggressive behaviour of stranded fry triggered a second pulse three weeks later. This pulse reduced stranding and initiated downstream migration. Prescribed flow pulses supported outmigration of a keystone species while minimising water use during a critical period. This study evaluated ecological responses to management actions intended to ameliorate stressful low flow conditions and provided a decision‐making framework that can be used when resource use conflicts arise again. 相似文献
4.
Transcriptomic analysis reveals olfactory‐related genes expression in large yellow croaker (Larimichthys crocea) regulated by taurine: May be a good phagostimulant for all‐plant protein diets 下载免费PDF全文
Jiabao Hu Yajun Wang Qijun Le Na Yu Xiaohuan Cao Huakun Zheng Siwen Kuang Man Zhang Junyong Zheng Xiaokai Wu Jianbo Wang Shunshun Tao Xiaojun Yan 《Aquaculture Research》2018,49(2):1095-1104