Navigation Links
Giant tortoises show rewilding can work
Date:4/21/2011

'Rewilding with taxon substitutes', the intentional introduction of exotic species to fulfil key functions in ecosystems following the loss of recently extinct species, is highly controversial, partly due to a lack of rigorous scientific studies.

In a paper published today in Current Biology, Christine Griffiths of Bristol's School of Biological Sciences and colleagues present the first empirical evidence that rewilding can work.

Exotic giant Aldabra tortoises, Aldabrachelys gigantea, were introduced to Ile aux Aigrettes, a 25-hectare island off Mauritius, in 2000 to disperse the slow-growing ebony Diospyros egrettarum (Ebenaceae), which once covered the island, but today is critically endangered following intensive logging for firewood that lasted until the early 1980s.

To highlight the extent to which the ebony forest had been decimated, the researchers surveyed and mapped all ebony trees in an island-wide survey in 2007 and located a total of 3,518 adult trees. However, large tracts of the island remained denuded of ebony, particularly in the northern and eastern coastal areas nearest to the mainland where logging was most intense.

There had been no regeneration in these areas even though logging ceased thirty years ago because, with the extinction of the island's native giant tortoises, there were no large fruit-eating animals left to disperse the seeds of these critically-endangered trees.

The introduced Aldabra tortoises not only ingested the large fruits and dispersed large numbers of ebony seeds, but the process of passing through a tortoise's gut also improved seed germination, leading to the widespread, successful establishment of new ebony seedlings in the heavily logged parts of the island.

Christine Griffiths said: "Our results demonstrate that the introduction of these effective seed dispersers is aiding the recovery of this critically endangered tree whose seeds were previously seed-dispersal limited. Reversible rewilding experiments such as ours are necessary to investigate whether extinct interactions can be restored."

Professor Stephen Harris, co-author of the study, said: "Ecological restoration projects generally involve the plant community, as more often the animal components are extinct. There is, however, increasing evidence that restoration ecologists should be most concerned with the decline of species interactions, rather than species extinctions per se. Species interactions structure ecological communities, and provide essential ecosystem processes and functions such as pollination, seed dispersal and browsing, that are necessary for the self-regulation and persistence of a community."


'/>"/>

Contact: Hannah Johnson
hannah.johnson@bristol.ac.uk
44-117-928-8896
University of Bristol
Source:Eurekalert

Related biology news :

1. Giant fire-bellied toads brain brims with powerful germ-fighters
2. Giant rats lead scientists to ancient face carvings
3. Researchers discover giant crayfish species right under their noses
4. Oil giant plans new platform near feeding ground of critically endangered whale
5. Old-growth forests are what giant pandas need
6. Giants among us: Paper explores evolution of the world’s largest mammals
7. Raising giant insects to unravel ancient oxygen
8. Efforts underway to rescue vulnerable bananas, giant swamp taro, other Pacific Island crops
9. New study shows how giant tortoises, alligators thrived in High Arctic 50 million years ago
10. Greenland glacier gives birth to giant iceberg
11. Extinct giant shark nursery discovered in Panama
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/25/2016)... , Jan. 25, 2016  Glencoe Software, the world-leading ... and publication industries, will provide the data management solution ... (NPSC). ... Phenotypic analysis measures the ... organisms, allowing comparisons between states such as health and ...
(Date:1/20/2016)... Jan. 20, 2016 A market that just ... benefit from the explosion in genomics knowledge. Learn all ... Research. A range of dynamic trends are pushing market ... personalized medicine - pharmacogenomics - pathogen evolution - next ... markets - greater understanding of the role of genetic ...
(Date:1/15/2016)... Puerto Rico , Jan. 15, 2016 ... big and small to find new ways to ensure ... culture. iOS and Android ... based on biometrics, transforming it into a hardware authorization ... that users swipe their fingerprint on their KodeKey enabled ...
Breaking Biology News(10 mins):
(Date:2/10/2016)... 2016  The Maryland House of Delegates and House ... University of Maryland School of Medicine Dean E. ... Maryland Medical System President and CEO Robert Chrencik ... highest honor given to the public by the leader ... Reece and Mr. Chrencik for their contributions to ...
(Date:2/10/2016)... 2016 ASAE is introducing a hybrid membership ... (AMC) the option of joining or renewing through an ... by staff size, every employee in any size association ... reap all available member benefits.   John ... membership options will allow organizations of any size and ...
(Date:2/10/2016)... -- IsoRay, Inc. (NYSE MKT: ISR), a medical technology company ... for the treatment of prostate, brain, lung, head and ... for the second quarter and six months of fiscal ... --> --> Revenue was $1.19 ... ended December 31, 2015, a 12% increase compared to ...
(Date:2/10/2016)... , Feb. 10, 2016  Matchbook, Inc., ... for fast growing biotech companies, announced today the ... Procurement Strategic Advisor. Jim brings nearly 25 years ... and procurement, having spent nearly two decades in ... Chain/Logistics and Procurement at Genzyme and, most recently ...
Breaking Biology Technology: