Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search

 


Fishing threatens rare dolphins in tourist hotspot

Fishing threatens rare dolphins in tourist hotspot: Otago study
Friday 5 July 2013

New research by University of Otago scientists has shown that the Hector’s dolphin, an endangered species found only in New Zealand, is more at risk from amateur fishing in Akaroa Harbour than had been thought.

Akaroa harbour is the largest harbour on Banks Peninsula, near Christchurch. It is home to a valuable dolphin-watching industry, which takes visitors to see and swim with Hector’s dolphins.

The team, comprising dolphin experts Professor Steve Dawson, Associate Professor Liz Slooten, and statistician Associate Professor David Fletcher, moored three “T-POD” acoustic devices in the inner, middle and outer parts of Akaroa Harbour. The devices logged the high-frequency echo-location signals of Hector’s dolphins over an entire year.

“Because Hector’s dolphin echo-location clicks are very different from those of other dolphins in New Zealand, we can tune the T-PODs to detect them specifically,” Prof Dawson said.

He says previously it was thought that Hector’s dolphins were present in the inner harbour only in summer.

“Because of this, amateur fishers were given a concession allowing them to set unattended set nets in this area for seven months of the year (1 April - 30 September). The nets, made of nylon mesh, can entangle dolphins and prevent them from surfacing for air,” he says.
The devices have a small detection radius, of about 200 metres. Despite this representing less than 1% of the inner harbour area, Hector’s dolphins were detected on 41% of the days during the recreational fishing concession period when set nets could be used.

“This shows that dolphins use this area much more regularly that previously thought, and that the concession offered to amateur gillnetters is not safe for the dolphins,”  he says.

“A crucial problem for Hector’s dolphins is that in several key areas the protection does not match the dolphins’ distribution. The new research shows this is true in Akaroa Harbour, but it is also true offshore around Banks Peninsula, where aerial surveys have shown that the dolphins range much further offshore than the protection extends. A large part of that population is essentially unprotected.”

The research also revealed how the dolphins use the harbour varies with location, season, time of day and tide. The research was published yesterday in the scientific journal Endangered Species Research.
http://www.int-res.com/abstracts/esr/v21/n1/

ENDS

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

Scoop Business: RBNZ Keeps OCR At 3.5%, Signals Slower Pace Of Future Hikes

Reserve Bank governor Graeme Wheeler kept the official cash rate at 3.5 percent and signalled he won’t be as aggressive with future rate hikes as previously thought as inflation remains tamer than expected. The kiwi dollar fell to a seven-month low. More>>

ALSO:

Weather: Dry Spells Take Hold In South Island

Many areas in the South Island are tracking towards record dry spells as relatively warm, dry weather that began in mid-August continues... for some South Island places, the current period of fine weather is quite rare. More>>

ALSO:

Scoop Business: Productivity Commission To Look At Housing Land Supply

The Productivity Commission is to expand on its housing affordability report with an investigation into improving land supply and development capacity, particularly in areas with strong population growth. More>>

ALSO:

Forestry: Man Charged After 2013 Death

Levin Police have arrested and charged a man with manslaughter in relation to the death of Lincoln Kidd who was killed during a tree felling operation on 19 December 2013. More>>

ALSO:

Smells Like Justice: Dairy Company Fined Over Odour

Dairy company fined over odour Dairy supply company Open Country Dairy Limited has been convicted and fined more than $35,000 for discharging objectionable odour from its Waharoa factory at the time of last year’s ”spring flush” when milk supply was high. More>>

Scoop Business: Dairy Product Prices Decline To Lowest Since July 2012

Dairy product prices dropped to the lowest level since July 2012 in the latest GlobalDairyTrade auction, led by a slump in rennet casein and butter milk powder. More>>

ALSO:

SOE Results: TVNZ Lifts Annual Profit 25% On Flat Ad Revenue, Quits Igloo

Television New Zealand, the state-owned broadcaster, lifted annual profit 25 percent, ahead of forecast and despite a dip in advertising revenue, while quitting its stake in the pay-TV Igloo joint venture with Sky Network Television. More>>

ALSO:

Get More From Scoop

 
 
Computer Power Plus

Standards New Zealand

Standards New Zealand

Mosh Social Media
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news