The legendary humpback Mahseer, one of the world's most iconic
freshwater fish, is on the brink of extinction according to scientists.
Ever since the publication of HS Thomas's A Rod in India in 1873, this
giant member of the carp family has been known to anglers around the
globe as 'one of the largest and hardest fighting freshwater fish in the
world'. With its distribution having always been limited to South
India's River Cauvery basin, this fish is now believed to be so
endangered it may be extinct in the wild within a generation.
Ever since the publication of HS Thomas's A Rod in India in 1873,
this giant member of the carp family has been known to anglers around
the globe as 'one of the largest and hardest fighting freshwater fish in
the world'. With its distribution having always been limited to South
India's River Cauvery basin, this fish is now believed to be so
endangered it may be extinct in the wild within a generation.
Adrian Pinder of Bournemouth University and Dr Rajeev Raghavan of St.
Albert's College have been studying the ecology, taxonomy and
conservation status of 17 species of mahseer which populate rivers
throughout south and southeast Asia since 2010. Four of these species
are already listed as 'Endangered' on the IUCN [International Union for
Conservation of Nature] Red List. Along with co-author Dr Robert
Britton, the paper, published in the international research journal
Endangered Species Research, clearly demonstrates that the endemic
humpbacked Mahseer is now of the brink of extinction having been
replaced by non-native relatives (blue-finned Mahseer) which have been
artificially bred and introduced to the river in the name of species
conservation.
The paper acknowledges that many pressures are placed upon the fish
of India's rivers, including pollution; poaching (using dynamite and
poisons); sand and gravel extraction; low river flows due to
abstraction; and India's continuing thirst for electricity, which has
resulted in dozens of hydro-electric which restrict the ability of fish
to migrate to their spawning grounds.
Against this backdrop of threats, this research suggests that the
introduction of non-native Mahseer has acted as the catalyst which has
had a catastrophic effect on the numbers of endemic Mahseer remaining in
the River Cauvery and its tributaries.
Adrian Pinder said, "This research all stems from my interest as an
angler, when as a boy I had read about this great fish. In 2010 I made
my first trip the River Cauvery, where I realised the fish I was
catching did not match the appearance of the iconic specimens I'd seen
in historic photos.
"On returning to the UK, I interrogated the scientific literature and
made contact with Dr Rajeev Raghavan based at St Albert's College
Kochi, to ask his opinion. Comparing photographs over the internet
opened a can of worms and confirmed that very little was known about all
of the Mahseer species found throughout south and south East Asia.
"As large monsoonal rivers are extremely difficult to survey, and
angling was banned in all protected areas in India in 2012, I started to
look for alternative data sources and discovered that the Galibore
Fishing Camp [one of three former angling camps in the Karnataka jungle]
had kept detailed angler catch records. This not only allowed us to
analyse the temporal trends in population size over the previous 15
years but also form a detailed understanding of how the type and species
of Mahseer had changed over time."
In 2012 Adrian Pinder and Dr Raghavan set up the Mahseer Trust, an
NGO working to protect Mahseer and its habitats. The Trust is now
working with national and international stakeholders to educate and
promote better informed fisheries management practices and to save the
humpback Mahseer from extinction.
Adrian Pinder concluded, "The blue-finned Mahseer, is not native to
the River Cauvery, yet our studies over the last two years have shown
that they are now one of the most abundant fish in the river. Without a
doubt, their success has been at the expense of the humpbacked Mahseer
that historically occurred throughout the entire river catchment.
Despite the positive intention of conservationists, this is clearly a
conservation programme which has backfired. The state of confusion
surrounding Mahseer taxonomy means the humpback Mahseer currently lacks a
valid scientific name and could potentially go extinct before being
named!"
"My current priority is on sourcing specimens of the endemic
humpbacked Mahseer. If we are not already too late, obtaining DNA from
this animal will allow us to name the fish and, based on our data, get
it classified as 'Critically endangered' on the IUCN Red List. When you
consider that the iconic Giant panda and tiger are classified as
'endangered' this puts things in context and demonstrates the urgency to
act in sourcing native fish for culturing in local hatcheries."
This story is taken from Science Daily
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