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

 


Non-native species not the bad guys in a changing eco-system

Non-native species not the bad guys in a changing eco-system

April 17, 2014

University of Canterbury researchers are investigating some positive features of animals being introduced to New Zealand.

Exotic animals are generally considered to be a major threat to native species in New Zealand and worldwide.

Despite numerous examples of invasive species harming ecosystems, exotic species may actually be able to fill ecological gaps in their new home, such as those left by native species that have gone extinct.

Professor Jason Tylianakis says this is one of the first examples of exotic species filling the roles left by declining natives across a whole range of species.

"A collaborative research project between scientists at the University of Canterbury and University of Oviedo, Spain, has examined the role of exotic birds in dispersing the seeds of native New Zealand trees and shrubs.

"Many fruiting plants require birds to carry their seeds to new locations and drive the persistence and recovery of native forests.

"New Zealand fruit-feeding birds have historically suffered a strong decline of native birds but they have also gained new fruit-eaters in the form of introduced European birds such as blackbirds and song thrushes."

The Canterbury researchers studied the network of feeding interactions between different species of plants and birds in the North and South Islands. They found that the intermediate body and beak size of exotic birds allowed them to feed on a great variety of different fruits.

This allowed the birds to disperse seeds of plant species that were not frequently eaten by native birds at any given location and helped to stabilise seed dispersal across a whole range of plants.

Without introduced species, many native plants would not have their fruits eaten and their seeds would simply fall to the ground below the tree.

Another Canterbury researcher Dr Daniel Stouffer says exotic species were less discriminating in their fruit consumption patterns.

"Native fruit-eaters have developed strong affinities for or against consumption of particular native fruit species making our native communities vulnerable to loss of key bird species. On the contrary, the exotic species were more than happy to make equal use of all the fruits available, thereby spreading their benefit more widely."

Professor Tylianakis says people often consider invasions by non-native species as always being harmful.

"However, many of our native species have already gone extinct and sometimes we need new species to fill their role. Although they often do harm, we can’t always assume that non-native species are the bad guys in our constantly-changing ecosystems,” Professor Tylianakis says.

ENDS

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

Statistics: Business Research And Development Up 29 Percent

Computer services and machinery manufacturing firms led the way in an almost 30 percent lift in business spending on research and development (R&D) in 2016, Stats NZ said today. Businesses spent $1.6 billion on R&D in 2016, up $356 million (29 percent) from 2014. More>>

ALSO:

China Shopping: NZ-China FTA Upgrade Agreed Among Slew Of New Deals

New Zealand Prime Minister Bill English and China Premier Li Keqiang signed off a series of cooperation deals spanning trade, customs, travel and climate change and confirmed commencement of official talks on an upgrade to the nine-year old free-trade agreement between the two countries. More>>

ALSO:

Media: TVNZ Flags Job Cuts To Arrest Profit Decline

Chief executive Kevin Kenrick said the changes were aimed at creating "a sustainable future video content business for TVNZ in an ever-changing media market." More>>

ALSO:

Reserve Bank: Wheeler Keeps OCR At 1.75%

Reserve Bank governor Graeme Wheeler kept the official cash rate unchanged at 1.75 percent, as expected, and reiterated his view that the benchmark rate doesn't need shifting for the foreseeable future. More>>

ALSO:

Trade Plans: Prime Minister's Speech To International Business Forum

"The work to improve public services, build infrastructure, and solve social problems is possible only because we have enjoyed sustained, solid economic growth. A big reason for that is the Government’s consistent agenda of economic reform, and our determination to open up more opportunities for trade with the world." More>>

ALSO:

Get More From Scoop

 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news