Unfortunately, we missed the chance for a better scenario several years ago.
But hey – have a consolation prize.
A little chocolate to sweeten your naivety?
Take a look at a more realistic level.
Oh – you still believe in a perfect world?
Did you really think there was a better scenario?
You dreamer, you.
Unfortunately, we can’t turn back time.
The past is gone for good.
Can’t handle reality?
It’s okay – we’ve got something to help you.
While terrestrial biodiversity may in some places benefit from higher temperatures, species diversity in and around water is already among the losers of climate change.
Drought and heat threaten the growth, reproduction, distribution, health, and survival of fish and other aquatic organisms. During late-summer heatwaves, smaller lakes can develop carpets of algal blooms due to high water temperatures, reducing oxygen levels in the water.
If fish are unable to migrate to other water bodies – either because such refuges do not exist or they are blocked by impassable dams – they quickly reach their physiological limits.
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Drought and higher water temperatures harm native fish and aquatic organisms. Habitats shrink and disease increases. back to Heat
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High water temperatures alter oxygen and nutrient availability for fish and other aquatic organisms, leading to stress. back to Water Balance
In certain regions, waters are already so warm that fish die en masse if they cannot escape to cooler waters. Cold-adapted aquatic species, and those that depend on specific ecological niches, are increasingly displaced by heat-tolerant, less sensitive species such as the invasive quagga mussel.
Not even swimming is fun anymore.
In overly warm waters, cyanobacteria (so-called blue-green algal blooms) become a problem, particularly where phosphorus concentrations are elevated due to current or past over-fertilisation. Their toxins can cause vomiting and diarrhoea in humans – and may even be fatal for dogs!
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Habitats with suitable water temperatures are shrinking, making survival and reproduction increasingly difficult for fish. back to Heat
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In many water bodies, rising water temperatures and shrinking habitats are causing fish die-offs. back to Water Balance
Where water still flows, low water levels cause such intense warming that fish mortality increases dramatically. Many small to medium-sized streams dry out completely, destroying aquatic flora and fauna.
Water bodies that regularly run dry become almost dead biologically, as species can no longer migrate into them.
In lakes, climate-driven warming leads to more stable stratification, weakening – or even preventing – the mixing of oxygen in autumn and winter. This creates oxygen-depleted zones that threaten fish and bottom-dwelling organisms. Blue-green algae blooms occur more frequently, especially in mid- to late summer.
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Existing habitats become unsuitable for many aquatic creatures due to rising water temperatures. The first species die out. back to Heat
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Extreme temperatures and the drying up of smaller water bodies lead to mass mortality of aquatic organisms. back to Water Balance
That's it. RIP.
That's a bit too much.
Maybe go down a level?
Got it – you're really into extremes.
Game over.
Try a different level.
That extreme? You’ll find the matching soundtrack here.
We’re done with this planet.
On to the next!
Solutionsfor: Fish Mortality and Species Extinction
Natural watercourses are the most resilient to warming. Protected areas for species conservation, as well as riverbank restoration and renaturalization measures, help create cooler and more structurally diverse habitats. 'Sponge' landscapes that retain water more effectively help ensure adequate drainage. Fish ladders support migration.
Regulation is also required: hydropower plants can adjust production to comply with minimum flow requirements, reduce reservoir temperatures, and limit hydropeaking impacts. To monitor temperature stress in fish, a four-week forecast is available. In extreme cases, fish can be temporarily removed from a body of water and then reintroduced once temperatures drop or water flow returns.