Navigation Links
Butterfly fish 'may face extinction'

A beautiful black, white and yellow butterflyfish, much admired by eco-tourists, divers and aquarium keepers alike, may be at risk of extinction, scientists have warned.

The case of the Chevroned Butterflyfish is a stark example of how human pressure on the worlds coral reefs is confronting certain species with blind alleys from which they may be unable to escape, says Dr Morgan Pratchett of the ARC Centre of Excellence for Coral Reef Studies Media Release and James Cook University.

In a study published in the journal Behavioural Ecology and Sociobiology Dr Pratchett and Dr Michael Berumen of Woods Hole Oceanographic Institution (USA) warn that the highly specialized nature of the feeding habits of this particular butterflyfish the distinctively patterned Chaetodon trifascialis - make it an extinction risk as the worlds coral reefs continue to degrade due to human over-exploitation, pollution and climate change.

The irony is that these butterflyfish are widespread around the world, and youd have thought their chances of survival were pretty good, Dr Pratchett said today.

But they only eat one sort of coral Acropora hyacinthus and when that runs out, the fish just disappear from the reef.

The team found it hard to believe a fish would starve rather than eat a mixed diet, so they tested C. trifascialis in tank trials on a range of different corals. The fish grew well when its favourite coral was available but when this was removed and other sorts of corals offered, it grew thin, failed to thrive and some died.

We call these kinds of fish obligate specialists. It means they have a very strong dietary preference for one sort of food, and when that is no longer available, they go into decline. We still dont have a satisfactory scientific explanation for this, as it seems like rather a risky tactic in evolutionary terms but it must confer some advantage provided enough of its preferred food is available, Dr Pratchett says.

The A. hyacinthus coral, which the butterfly fish feeds on, is itself highly vulnerable to attacks by plagues of crown-of-thorns starfish (thought to be triggered by humans releasing excess nutrients onto the reef as sediment, fertilizer or sewage), to storms and to the coral bleaching caused by the heating of ocean surface waters to 32 degrees or more, which is thought to be linked to global warming.

Although extremely widespread, the Chevroned butterflyfish may be at considerable risk of extinction following ongoing degradation of coral reefs around the world, because the coral itself is exceptionally vulnerable, Dr Pratchett explains.

It is estimated that up to 70 per cent of the worlds coral reefs are now badly degraded, which usually involves the loss of this particular coral and, when it goes, the C. trifascialis also disappear from the reef.

To make matters worse, butterflyfishes are one of the main families of coral reef fishes being targeted by aquarium collectors. However, the specialized coral-eaters are clearly not suitable for keeping in aquaria - and often die because they cannot obtain their main food source.

A previous case in which a coral-dependent fish vanished occurred in the case of Gobiodon a specialized coral-dweller known only from one site, Kimbe Bay in Papua New Guinea, which was thought by scientists to have possibly become extinct after its habitat was destroyed.

Researchers consider that such extinctions are likely to occur as part of the global mass extinction of species now taking place, and that marine ecosystems may be particularly vulnerable in that small changes in habitat or water quality can have a big impact on their species.

Dr Pratchett and Dr Berumen say theirs is one of the few studies so far to consider the evolutionary and ecological basis of dietary versatility, and has implications for the fate of specialised feeders throughout the animal kingdom.


Contact: Dr. Morgan Pratchett
ARC Centre of Excellence in Coral Reef Studies

Related biology news :

1. UF to auction naming rights for new butterfly species online
2. New study uncovers secrets behind butterfly wing patterns
3. UFs new owl butterfly species naming rights auctioned for $40,800
4. Report: African, Asian, Latin American farm animals face extinction
5. Scientists fear rare dolphin driven to extinction by human activities
6. Research team says extraterrestrial impact to blame for Ice Age extinctions
7. Fossil record supports evidence of impending mass extinction
8. Meteor no longer prime suspect in great extinction
9. NAS Biodiversity and Extinction Meeting Dec. 7-8
10. Scientists warn that species extinction could reduce productivity of plants on Earth by half
11. Stanford researchers say climate change will significantly increase impending bird extinctions
Post Your Comments:
(Date:11/17/2015)... PARIS , November 17, 2015 ... 17 au 19 novembre  2015.  --> Paris ... 2015.  --> DERMALOG, le leader de l,innovation ... à la fois passeports et empreintes sur la même ... pour les passeports et l,autre pour les empreintes digitales. ...
(Date:11/16/2015)... Nov 16, 2015  Synaptics Inc. (NASDAQ: ... solutions, today announced expansion of its TDDI product ... touch controller and display driver integration (TDDI) solutions ... These new TDDI products add to the previously-announced ... TD4302 (WQHD resolution), and TD4322 (FHD resolution) solutions. ...
(Date:11/12/2015)... 11, 2015   Growing need for low-cost, ... has been paving the way for use of ... discrete analytes in clinical, agricultural, environmental, food and ... used in medical applications, however, their adoption is ... to continuous emphasis on improving product quality and ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... ... November 24, 2015 , ... ... But unless it is bound to proteins, copper is also toxic to cells. ... at Worcester Polytechnic Institute (WPI) will conduct a systematic study of copper in ...
(Date:11/24/2015)... PUNE, India , November 24, 2015 ... to a new market research report "Oligonucleotide Synthesis Market ... Equipment), Application (PCR, Gene Synthesis, Diagnostic, DNA, RNAi), End-User ... to 2020", published by MarketsandMarkets, the market is expected ... 1,078.1 Million in 2015, at a CAGR of 10.1% ...
(Date:11/24/2015)... New York , November 24, 2015 ... to a recent market research report released by Transparency ... projected to expand at a CAGR of 17.5% during ... "Non-invasive Prenatal Testing Market - Global Industry Analysis, Size, ... estimates the global non-invasive prenatal testing market to reach ...
(Date:11/24/2015)... ... November 24, 2015 , ... ... are paramount. Insertion points for in-line sensors can represent a weak spot where ... InTrac 781/784 series of retractable sensor housings , which are designed to tolerate ...
Breaking Biology Technology: