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

 

Price Of Cheese: Dairy Product Prices Fall To The Lowest This Year

Dairy product prices fell in the latest GlobalDairyTrade auction, hitting the lowest level in the 2015 auctions so far, as prices for milk powder and butter slid amid concern about the outlook for commodities. More>>

ALSO:

Houston, We Have An Air Route: Air New Zealand To Fly Direct To The Heart Of Texas

Air New Zealand will fly its completely refitted Boeing 777-200 aircraft between Auckland and Houston up to five times a week opening up the state of Texas as well as popular nearby tourist states such as Louisiana and Florida. More>>

ALSO:

Scoop Business: Reserve Bank’s Spencer Calls On Govt To Rethink Housing Tax

The Reserve Bank has urged the government to take another look at a capital gains tax on investment in housing, allow increased high-density development and cut red tape for planning consents to address an over-heated Auckland property market. More>>

ALSO:

The Nation: Call For Cross-Party Auckland Housing Plan

Penny Hulse calls for cross-party accord on Auckland housing because “it’s too important to score political points on”. More>>

ALSO:

Flu Season: Overcoming Vaccination Reluctance

While research shows that 40% of New Zealand businesses offer free or subsidised flu vaccinations to employees this time of year, HR professionals say persuading staff to participate is the biggest challenge. More>>

ALSO:

Get More From Scoop

 
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news