The interaction of exposure and warming tolerance determines fish species vulnerability to warming stream temperatures

Species vulnerability to climate change involves an interaction between the magnitude of change (exposure) and a species's tolerance to change. We evaluated fish species vulnerability to predicted stream temperature increases by examining warming tolerances across the Wyoming fish assemblage. Warming tolerance combines stream temperature with a thermal tolerance metric to estimate how much warming beyond current conditions a species can withstand. Brown trout, rainbow trout and burbot had the lowest warming tolerances and the highest proportion of currently occupied sites that will become unsuitable under predicted temperature increases. These most vulnerable species were coldwater species, but had neither the lowest thermal tolerances nor would they experience the greatest temperature increases. Our results highlight the importance of considering the interaction of exposure and warming tolerance when predicting climate change vulnerability and demonstrate an approach that can be applied broadly.

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Reflections on a seminal paper in conservation biology: the legacy of Peters and Darling (1985)

Pacific Conservation Biology ◽

10.1071/pc18004 ◽

2018 ◽

Vol 24 (3) ◽

pp. 267

Author(s):

Lesley Hughes

Keyword(s):

Climate Change ◽

Conservation Biology ◽

Extinction Risk ◽

Logical Framework ◽

Natural Ecosystems ◽

Seminal Paper ◽

Species Vulnerability ◽

Vulnerability To Climate Change ◽

Species Translocation ◽

Rapid Environmental Change

‘The Greenhouse Effect and Nature Reserves’ by Robert Peters and Joan Darling, published in the journal Bioscience more than 30 years ago, was a ground-breaking synthesis. Drawing on paleoecology, community ecology and biogeography, the review laid out many concepts about species vulnerability to climate change that have become central tenets of research on climate change adaptation in natural ecosystems. Remarkably, the paper also provided a clear and logical framework for flexible, forward-thinking and interventionist management action, including recommendations about the design of protected areas, and the need for species translocation to reduce extinction risk. Reflecting on the legacy of this paper, it is clear that the uptake of such approaches over the intervening decades has been extremely slow, representing many lost opportunities to reduce species vulnerability to rapid environmental change. This paper is a tribute to the prescience of Peters and Darling, and a call to revisit their farsighted advice to meet conservation challenges that continue to accelerate.

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Intraspecific variation in thermal tolerance differs between tropical and temperate fishes

Scientific Reports ◽

10.1038/s41598-021-00695-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

J. J. H. Nati ◽

M. B. S. Svendsen ◽

S. Marras ◽

S. S. Killen ◽

J. F. Steffensen ◽

...

Keyword(s):

Climate Change ◽

Global Warming ◽

Intraspecific Variation ◽

Fish Species ◽

Thermal Tolerance ◽

Evolutionary History ◽

Ecological Impacts ◽

Temperate Species ◽

Tropical Species ◽

Upper Thermal Tolerance

AbstractHow ectothermic animals will cope with global warming is a critical determinant of the ecological impacts of climate change. There has been extensive study of upper thermal tolerance limits among fish species but how intraspecific variation in tolerance may be affected by habitat characteristics and evolutionary history has not been considered. Intraspecific variation is a primary determinant of species vulnerability to climate change, with implications for global patterns of impacts of ongoing warming. Using published critical thermal maximum (CTmax) data on 203 fish species, we found that intraspecific variation in upper thermal tolerance varies according to a species’ latitude and evolutionary history. Overall, tropical species show a lower intraspecific variation in thermal tolerance than temperate species. Notably, freshwater tropical species have a lower variation in tolerance than freshwater temperate species, which implies increased vulnerability to impacts of thermal stress. The extent of variation in CTmax among fish species has a strong phylogenetic signal, which may indicate a constraint on evolvability to rising temperatures in tropical fishes. That is, in addition to living closer to their upper thermal limits, tropical species may have higher sensitivity and lower adaptability to global warming compared to temperate counterparts. This is evidence that freshwater tropical fish communities, worldwide, are especially vulnerable to ongoing climate change.

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Climate‐niche factor analysis: a spatial approach to quantifying species vulnerability to climate change

Ecography ◽

10.1111/ecog.03937 ◽

2019 ◽

Vol 42 (9) ◽

pp. 1494-1503 ◽

Cited By ~ 4

Author(s):

D. Scott Rinnan ◽

Joshua Lawler

Keyword(s):

Climate Change ◽

Factor Analysis ◽

Climate Niche ◽

Species Vulnerability ◽

Vulnerability To Climate Change ◽

Spatial Approach ◽

Niche Factor

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Thermal bottlenecks in the life cycle define climate vulnerability of fish

Science ◽

10.1126/science.aaz3658 ◽

2020 ◽

Vol 369 (6499) ◽

pp. 65-70 ◽

Cited By ~ 26

Author(s):

Flemming T. Dahlke ◽

Sylke Wohlrab ◽

Martin Butzin ◽

Hans-Otto Pörtner

Keyword(s):

Life Cycle ◽

Fish Species ◽

Thermal Tolerance ◽

Thermal Adaptation ◽

Inverse Correlation ◽

Climate Projections ◽

Temperature Sensitive ◽

Life Stages ◽

Ontogenetic Changes ◽

Species Vulnerability

Species’ vulnerability to climate change depends on the most temperature-sensitive life stages, but for major animal groups such as fish, life cycle bottlenecks are often not clearly defined. We used observational, experimental, and phylogenetic data to assess stage-specific thermal tolerance metrics for 694 marine and freshwater fish species from all climate zones. Our analysis shows that spawning adults and embryos consistently have narrower tolerance ranges than larvae and nonreproductive adults and are most vulnerable to climate warming. The sequence of stage-specific thermal tolerance corresponds with the oxygen-limitation hypothesis, suggesting a mechanistic link between ontogenetic changes in cardiorespiratory (aerobic) capacity and tolerance to temperature extremes. A logarithmic inverse correlation between the temperature dependence of physiological rates (development and oxygen consumption) and thermal tolerance range is proposed to reflect a fundamental, energetic trade-off in thermal adaptation. Scenario-based climate projections considering the most critical life stages (spawners and embryos) clearly identify the temperature requirements for reproduction as a critical bottleneck in the life cycle of fish. By 2100, depending on the Shared Socioeconomic Pathway (SSP) scenario followed, the percentages of species potentially affected by water temperatures exceeding their tolerance limit for reproduction range from ~10% (SSP 1–1.9) to ~60% (SSP 5–8.5). Efforts to meet ambitious climate targets (SSP 1–1.9) could therefore benefit many fish species and people who depend on healthy fish stocks.

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