Sharing the water column: physiological mechanisms underlying species-specific habitat use in tunas

To increase our understanding of the interaction between fish and baited fishing gear we quantitatively described the behaviour of cod (Gadus morhua), saithe (Pollachius virens), and haddock (Melanogrammus aeglefinus) to baited pots in a fjord in northern Norway. Detailed video analyses were made to describe species specific responses and examine the effect of lifting the pot off the bottom. The majority of both cod and saithe approached the pots in an upstream direction, and fish approached floated pots higher in the water column than bottom set pots. Cod tended to approach a pot along the seabed and were more likely to encounter the bottom set pot than the floated pot, whereas saithe more often approached in the water column. The capture efficiency was low for all species, but cod were more likely to be caught than saithe and haddock. Cod showed a high encounter rate, low entrance rate and high escape rate. For saithe, a low encounter rate was the chief factor limiting capture efficiency. The observed differences between cod and saithe were explained by species-specific food-search strategies. No difference in entrance rate, escape rate or catch efficiency between the two pot types were found.

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Overwinter thermal habitat use in lakes by anadromous Arctic char

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2017-0420 ◽

2018 ◽

Vol 75 (12) ◽

pp. 2343-2353 ◽

Cited By ~ 10

Author(s):

Ingeborg M. Mulder ◽

Corey J. Morris ◽

J. Brian Dempson ◽

Ian A. Fleming ◽

Michael Power

Keyword(s):

Habitat Use ◽

Water Column ◽

Prey Capture ◽

Salvelinus Alpinus ◽

Late Summer ◽

Arctic Char ◽

Foraging Efficiency ◽

Thermal Habitat ◽

Metabolic Costs ◽

Seaward Migration

Anadromous Arctic char (Salvelinus alpinus) migrate back to fresh water in late summer to spawn and (or) overwinter. Upon freshwater entry, feeding is reduced or absent, and movement activity is restricted. While the physiological responses to low temperatures (e.g., growth, metabolism) are understood, specifics of the use of thermal habitat for overwintering remains poorly characterized. This study used acoustic and archival telemetry data from two lakes in southern Labrador, Canada, to study thermal habitat use during the ice-covered period. Results showed that lake-dwelling anadromous Arctic char predominantly occupied a narrow range of temperatures (0.5–2 °C) and used cooler temperatures available within the middle and upper water column. Use of the selected temperatures is likely a strategy that lowers metabolic costs and minimizes energy expenditure, preserving stored lipids for overwinter survival and the energetic costs of preparation for seaward migration. As Arctic char are visual feeders, use of the upper water column is also thought to aid foraging efficiency by increasing the likelihood of prey capture.

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Differentiation in Leaf Physiological Traits Related to Shade and Drought Tolerance Underlies Contrasting Adaptations of Two Cyclobalanopsis (Fagaceae) Species at the Seedling Stage

Forests ◽

10.3390/f11080844 ◽

2020 ◽

Vol 11 (8) ◽

pp. 844 ◽

Cited By ~ 1

Author(s):

Ai-Ying Wang ◽

Guang-You Hao ◽

Jing-Jing Guo ◽

Zhi-Hui Liu ◽

Jiao-Lin Zhang ◽

...

Keyword(s):

Drought Tolerance ◽

Environmental Gradients ◽

High Irradiance ◽

Tree Seedlings ◽

Physiological Mechanisms ◽

Full Sunlight ◽

Leaf Hydraulics ◽

Naturally Occurring ◽

Species Specific ◽

Distinct Distribution

Adaptation and acclimation of tree seedlings to different combinations of light and water conditions can determine the species-specific patterns of distribution along environmental gradients and the underlying physiological mechanisms are fundamental to the understanding of such patterns. Seedlings of two Cyclobalanopsis species naturally occurring in southwest China, with distinct distribution and regeneration characteristics, were grown under 100%, 50% and 4% sunlight conditions and traits related to shade and drought tolerance were studied. Particularly, we investigated whether leaf hydraulics, photosynthetic traits and their functional coordination play an important role in determining seedling environmental adaptation and acclimation of the two species. Seedlings of C. helferiana showed characteristics adapted to high irradiance while C. rex had traits adapted to partially shaded environments. Cyclobalanopsis helferiana had significantly higher maximum net photosynthetic rate (Amax), light compensation point and light saturation point than C. rex and the contrasts were particularly large when they were grown under full sunlight. Cyclobalanopsis helferiana showed the highest Amax when grown under 100% sunlight, while C. rex exhibited the highest Amax at 50% sunlight. Similarly, under full sunlight conditions C. helferiana showed significantly higher leaf hydraulic conductance (Kleaf) than C. rex, i.e., 13.37 vs. 7.09 mmol m−2 s−1 MPa−1 (p < 0.01). The correlation between Kleaf and Amax followed a unified positive correlation across different light treatments of both species. Moreover, leaves of C. helferiana showed greater resistance to drought-induced hydraulic dysfunction and to desiccation than C. rex. The contrasts in functional traits between the two Cyclobalanopsis species are consistent with the hypothesis that there is a trade-off between shade tolerance and drought tolerance. Findings of the present study contribute to a deeper understanding of mechanisms of divergence between closely related (congeneric) species with respect to key ecophysiology associated with natural regeneration.

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Water column structure influences long-distance latitudinal migration patterns and habitat use of bumphead sunfish Mola alexandrini in the Pacific Ocean

Scientific Reports ◽

10.1038/s41598-021-01110-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ching-Tsun Chang ◽

Wei-Chuan Chiang ◽

Michael K. Musyl ◽

Brian N. Popp ◽

Chi Hin Lam ◽

...

Keyword(s):

Habitat Use ◽

Water Column ◽

New Caledonia ◽

Long Distance ◽

Okinawa Island ◽

Migration Patterns ◽

Vertical Movements ◽

Near Surface ◽

The Pacific ◽

Utilization Patterns

AbstractSatellite-tracking of adult bumphead sunfish, Mola alexandrini, revealed long-distance latitudinal migration patterns covering thousands of kilometers. Horizontal and vertical movements of four bumphead sunfish off Taiwan were recorded with pop-up satellite archival tags in 2019–2020. Two individuals moved northward and traveled to Okinawa Island and Kyushu, Japan and two moved southwards; crossing the equator, to Papua New Guinea and New Caledonia. During daytime, bumphead sunfish descended below the thermocline and ascended to mixed layer depths (MLD) during nighttime. The N–S migrants, however, demonstrated different habitat utilization patterns. Instead of using prevailing currents, the northward movements of sunfish cohorts exhibited extensive use of mesoscale eddies. Fish in anticyclonic eddies usually occupied deeper habitats whereas those in cyclonic eddies used near-surface habitats. On northward excursions, fish spent most of their time in regions with high dissolved oxygen concentrations. Southward movement patterns were associated with major currents and thermal stratification of the water column. In highly stratified regions, fish stayed below the thermocline and frequently ascended to MLD during daytime either to warm muscles or repay oxygen debts. These results for bumphead sunfish present important insights into different habitat use patterns and the ability to undergo long-distance migrations over varying spatial-temporal scales and features.

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Modeling seasonal and vertical habitats of planktonic foraminifera on a global scale

10.5194/bg-2017-429 ◽

2017 ◽

Author(s):

Kerstin Kretschmer ◽

Lukas Jonkers ◽

Michal Kucera ◽

Michael Schulz

Keyword(s):

Climate Change ◽

Water Column ◽

Planktonic Foraminifera ◽

World Ocean ◽

Warm Season ◽

Cold Season ◽

Vertical Dimension ◽

Time Space ◽

Species Specific ◽

Water Species

Abstract. Species of planktonic foraminifera exhibit specific seasonal production patterns and different preferred vertical habitats. The seasonality and vertical habitats are not constant throughout the range of the species and changes therein must be considered when interpreting paleoceanographic reconstructions based on fossil foraminifera. Accounting for the effect of vertical and seasonal habitat tracking on foraminifera proxies at times of climate change is difficult because it requires independent fossil evidence. An alternative that could reduce the bias in paleoceanographic reconstructions is to predict species-specific habitat shifts under climate change using an ecosystem modeling approach. To this end, we present a new version of a planktonic foraminifera model, PLAFOM2.0, embedded into the ocean component of the Community Earth System Model, version 1.2.2. This model predicts monthly global concentrations of the planktonic foraminiferal species: Neogloboquadrina pachyderma, N. incompta, Globigerina bulloides, Globigerinoides ruber (white), and Trilobatus sacculifer throughout the world ocean, resolved in 24 vertical layers to 250 m depth. The resolution along the vertical dimension has been implemented by applying the previously used spatial parameterization of biomass as a function of temperature, light, nutrition, and competition on depth-resolved parameter fields. This approach alone results in the emergence of species-specific vertical habitats, which are spatially and temporally variable. Although an explicit parameterization of the vertical dimension has not been carried out, the seasonal and vertical distribution patterns predicted by the model are in good agreement with sediment trap data and plankton tow observations. In the simulation, the colder-water species N. pachyderma, N. incompta, and G. bulloides show a pronounced seasonal cycle in their depth habitat in the polar and subpolar regions, which appears to be controlled by food availability. During the warm season, these species preferably occur in the subsurface, while towards the cold season they ascend through the water column and are found closer to the sea surface. The warm-water species G. ruber (white) and T. sacculifer exhibit a less variable shallow depth habitat with highest biomass concentrations within the top 40 m of the water column. Nevertheless, even these species show vertical habitat variability and their seasonal occurrence outside the tropics is limited to the warm surface layer that develops at the end of the warm season. The emergence in PLAFOM2.0 of species-specific vertical habitats that are consistent with observations indicates that the population dynamics of planktonic foraminifera species may be driven by the same factors in time, space, and with depth, in which case the model can provide a reliable and robust tool to aid the interpretation of proxy records.

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Species-specific habitat use of wing-moulting waterbirds in response to temporary flightlessness

Ibis ◽

10.1111/ibi.12190 ◽

2014 ◽

Vol 156 (4) ◽

pp. 850-863 ◽

Cited By ~ 2

Author(s):

Andrea Gehrold

Keyword(s):

Habitat Use ◽

Species Specific

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Fine‐scale habitat use of foraging sperm whales is driven by seafloor topography and water column structure

Marine Mammal Science ◽

10.1111/mms.12881 ◽

2021 ◽

Author(s):

Marta Guerra ◽

Stephen M. Dawson ◽

Tamlyn R. Somerford ◽

Elizabeth Slooten ◽

William J. Rayment

Keyword(s):

Habitat Use ◽

Water Column ◽

Fine Scale ◽

Sperm Whales ◽

Seafloor Topography ◽

Column Structure

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Habitat use by Astyanax taeniatus (Jenyns, 1842) (Characiformes: Characidae) in a coastal stream from Southeast Brazil

Neotropical Ichthyology ◽

10.1590/s1679-62252014000100020 ◽

2014 ◽

Vol 12 (1) ◽

pp. 187-192 ◽

Cited By ~ 4

Author(s):

Luisa Resende Manna ◽

Carla Ferreira Rezende ◽

Rosana Mazzoni

Keyword(s):

Habitat Use ◽

Water Column ◽

Rio De Janeiro ◽

Water Velocity ◽

The State ◽

Microhabitat Use ◽

Underwater Observation ◽

Electivity Index ◽

Southeast Brazil ◽

Stream Bank

The habitat use of a stream-dwelling Astyanax taeniatus from the State of Rio de Janeiro was investigated. We performed 12 h of underwater observation in a 200 m long stretch in the upper Roncador stream and quantified the following microhabitat descriptors: (i) water velocity, (ii) distance from the stream bank, (iii) substratum, and (iv) water column depth. Microhabitat selectivity was analyzed by comparing the microhabitat used by fish and the microhabitat available in the study site as well as by applying the Ivlev Electivity Index to the microhabitat use data. Differences in the use and availability of the various microhabitats revealed non-stochastic patterns of spatial occupation by A. taeniatus, which was selective for two of the four analyzed microhabitats. Our findings indicated that A. taeniatusis associated with habitats that have higher depths, low water velocity, and sand and bedrock substratum.

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