Melting polar ice, rising sea levels not only climate change dangers

February 17, 2017

Climate change from political and ecological standpoints is a constant in the media and with good reason, said a Texas A&M AgriLife Research scientist, but proof of its impact is sometimes found in unlikely places.

"Discussions of usually are focused on changes occurring in polar and temperate zones, but also are expected to experience changes in regional precipitation," said Dr. Kirk Winemiller, AgriLife Research fisheries scientist and Regents Professor in the department of wildlife and fisheries sciences at College Station.

Winemiller and his Brazilian colleagues analyzed a long-term database, 1999-2014, of fish survey statistics and hydrology in the central Amazon and discovered a direct correlation between water quantity and quality with the types and number of fish species found.

"The change occurred following the severe drought in that region in 2005, and the hydrologic regime and fish assemblage have not returned to their previous states since," Winemiller said.

The research report, "Simultaneous abrupt shifts in hydrology and fish assemblage structure in a floodplain lake in the central Amazon," was published recently in Scientific Reports.

"The Amazon region is showing evidence of altered rainfall patterns," Winemiller said. "Until this study, with few exceptions, studies of potential effects of climate change in the Amazon have focused on forests and other organisms on land.

"Since the drought, many fish species are less abundant within the study area, while others have increased. Smaller species with high reproductive rates have increased, while large species, including those with the highest consumer market value, have become less prevalent."

As an example, Winemiller cited the relative abundance of the tambaqui, Colossoma macropomum, one of the region's most valuable species in Amazon fish markets, declined in relative abundance within the study area after the 2005 drought and has not increased its numbers since. He said the species feeds on fruits and seeds in flooded forests and is sensitive to changes in the annual flood regime hydrology.

Winemiller said the changes within the fish species appeared to be associated with how the respond differently to changes in habitat quality and the connectivity of the river channel with aquatic habitats in the floodplain at various water levels and times of the year.

"The study reveals that climate change is impacting tropical regions with consequences not only for terrestrial ecosystems, but for aquatic ecosystem dynamics, biodiversity and fisheries as well," he said. "It shows that future fisheries management in tropical regions will need to account for how changes in precipitation and hydrology influence ecological factors affecting fish stocks."

Explore further: Dam projects on world's largest rivers threaten fish species, rural livelihoods

More information: Cristhiana P. Röpke et al. Simultaneous abrupt shifts in hydrology and fish assemblage structure in a floodplain lake in the central Amazon, Scientific Reports (2017). DOI: 10.1038/srep40170

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14 comments

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philstacy9
2 / 5 (8) Feb 17, 2017
The danger is the corruption of science by subverting it to promote political agendas.
Ojorf
4.6 / 5 (9) Feb 18, 2017
The science is pretty clear. It is politics & greed that are attempting so very hard to obscure the picture.
Da Schneib
5 / 5 (6) Feb 18, 2017
And the more science we see, and the more greed and politics and lies, the more clear it becomes. Science always wins in the end.
gkam
2.1 / 5 (7) Feb 18, 2017
How are they going to deny this?

I want to see it.
antigoracle
1.6 / 5 (7) Feb 18, 2017
AGW Cult doom and gloom alert!!
Life evolves to suit their environment. Run for the hills, we're all going to die.

PS: Don't look up, because we don't want the ignorant to see that the sky is not falling.

LOL
antialias_physorg
4.6 / 5 (9) Feb 18, 2017
Climate change from political and ecological standpoints is a constant in the media

It's important to note that this only goes for the US. nowehere else is the reporting nearly as constant on climate change, because there's no reason to harping on the blindingly obvious over and over.

I guess in the US they go more for the infotainment angle, since TV consumers want emotionally charged stories.
RealityCheck
3.9 / 5 (7) Feb 18, 2017
Hi antigoracle. :)
AGW Cult doom and gloom alert!!
Life evolves to suit their environment. Run for the hills, we're all going to die.

PS: Don't look up, because we don't want the ignorant to see that the sky is not falling.
You're sounding like a 'broken record' now, mate. You conveniently ignore that adaptation involves 'casualties' along the way; and the more sudden/overwhelming the 'environmental pressures' to adapt, the more 'casualties'; at times leading to extinction of whole species or chain of species inter-dependent for their mutual survival.

I have pointed out that reality for you, but you keep resorting to 'slogans and memes' which arise/propagate only in the 'minds' (I apply that term loosely in many cases) of those steeped/doomed in/by ignorance and malice resulting from their own all-too-human foibles and self-interests which cannot see beyond the next 'minute' let alone decades ahead.

Are you really as ignorant/irresponsible as you 'sound', mate?
FactsReallyMatter
1 / 5 (4) Feb 20, 2017
This must be one of those selected regional effects that the AGW cult love.

Deforestation is having a much, much more significant impact on the amazon than anything to do with AGW. But better to ignore that I suppose.
SteveS
5 / 5 (1) Feb 20, 2017
Deforestation is having a much, much more significant impact on the amazon than anything to do with AGW.


Opinions are fine, but if you want anybody to be swayed by your arguments you have to provide supporting evidence, after all facts really matter.
FactsReallyMatter
1 / 5 (3) Feb 20, 2017
Opinions are fine, but if you want anybody to be swayed by your arguments you have to provide supporting evidence, after all facts really matter.


Ohhh, you got me. I am sure that 20% loss in 45 years is just a minor thing. Let's spend more money researching AGW impacts.
SteveS
4 / 5 (4) Feb 20, 2017
Ohhh, you got me. I am sure that 20% loss in 45 years is just a minor thing. Let's spend more money researching AGW impacts.


So without being able to quantify the impacts AGW will have on the Amazon you are still convinced that the impact of deforestation will be worse. To believe without evidence, that my friend is faith.

That said deforestation is a serious problem but one that is being addressed

https://mongabay-...azon.jpg

It would be a shame to waste all that hard work by neglecting studies into the deleterious effects of AGW such as this one. I would like to know the Amazon is safe, not just take it on faith.
Guy_Underbridge
3.7 / 5 (3) Feb 20, 2017
Ohhh, you got me. I am sure that 20% loss in 45 years is just a minor thing.
Don't you guys miss the days when the denier crowd had 'some' logic in their arguments? Anymore, they're not even as intellectually equipped as an IRC bot.
FactsReallyMatter
1 / 5 (4) Feb 20, 2017
If you would have read the paper instead of just making noise you would note the part where even the author admits deforestation and fishing are major drivers, not examined here.

As for deforestation being addressed - I suppose you providing a chart showing that it is still occurring about as much real "addressing" as one can expect from a cult that only want AGW as the panic button. Better to keep focus off the real problems.
SteveS
5 / 5 (1) Feb 20, 2017
even the author admits deforestation and fishing are major drivers, not examined here.


No the authors (plural) don't, but please feel free to quote from the paper.

http://www.nature...rep40170

As for deforestation being addressed - I suppose you providing a chart showing that it is still occurring about as much real "addressing" as one can expect from a cult that only want AGW as the panic button.


https://mongabay-...azon.jpg

Deforestation is still occurring but it's been decreasing since 2004, you're the one being the scare mongering cultist here.

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