Tuesday, March 15, 2011

THE HUNT FOR MYSTERY BEASTS TAKES A TORTUOUS TURN

Entering `Mystery Beast` into the youtube search engine elicits the news that there is a Japanese boy band called Beast who have a song called 'Mystery`. It is suitably horrible. Will wonders never cease?

HOOVERING THE DOG

Welcome to the old Devonshire custom of hoovering the dog. Whenever Helen comes to do the hoovering, Prudence insists on being hoovered too...

Where are missing mammals rediscovered?

Fisher, Diana O. (2011) Trajectories from extinction: Where are missing
mammals rediscovered? Global Ecology and Biogeography, In Press
http://onlinelibrary.wiley.com/doi/10.1111/j.1466-8238.2010.00624.x/abstract

http://dx.doi.org/10.1111/j.1466-8238.2010.00624.x

Aim: To determine where mammals that are presumed to be extinct are most likely to be rediscovered, and to test predictions of two hypotheses to explain trajectories of decline in mammals. Range collapse is based on
the premise that extinction rates at the edge of species ranges are highest because habitat is suboptimal, so declining species are predicted to survive longer near the centre of their ranges. We predicted that under
range collapse, remnant populations are most likely be rediscovered within their former core range. Conversely, if threats usually spread across ranges, declining species will be pushed to the periphery (range eclipse),
so rediscoveries are predicted at the edge of the pre-decline range. If so, species would be more likely to be rediscovered in marginal habitat, and at higher elevations than the sites from which they disappeared.

Methods  Using data on 67 species of mammals which have been rediscovered, I tested whether species were disproportionately rediscovered in the outer 50% of their former range area or at higher elevations than their last recorded locations, and which species characteristics were associated with rediscovery location and habitat
change, using both the phylogenetic generalized least squares method to account for phylogenetic non-independence and linear models of raw species data.

Results  Species affected by habitat loss were more likely to be rediscovered at the periphery than the centre of their former range, consistent with range eclipse caused by the spread of habitat destruction. High human population pressure predicted which species changed habitat between their previous records and rediscovery. Coastal species experienced higher human population densities, and were more likely to be rediscovered at the periphery of their former ranges, and there was some evidence of an up-slope shift associated with higher human populations at lower elevations.

Main conclusion  The locations of rediscoveries of species affected by habitat loss were consistent with range eclipse through a mechanism of spreading habitat loss and human population pressure, rather than with range collapse. Searches for mammals that have declined from habitat loss should include range edges and marginal habitat, especially in areas of high human population density.


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IUCN Releases Global Re-introduction Perspectives 2010

The second issue of the Global Re-introduction Perspectives series, released by the International Union for the Conservation of Nature (IUCN), contains 72 case studies on reintroduction efforts for the following taxa: invertebrates (9), fish (6), amphibians (5), reptiles (7), birds (13), mammals (20) and plants (12).

The series is published with the support of IUCN, the IUCN Species Survival Commission, Abu Dhabi Environment Agency, Saudi Wildlife Commission, Denver Zoological Foundation and Reintroduction Specialist Group. The case studies in the 2010 issue include the reintroductions of: Adriatic sturgeon in the Ticino River, Italy; Siamese crocodiles in Cambodia; saker falcon in Bulgaria; Asiatic black bear in Jirisan National Park, South Korea; and Arabian oryx in Saudi Arabia. Each case study includes the following sections: Introduction, Goals, Success, Indicators, Project Summary, Major Difficulties Faced, Major Lessons Learned, and Success of Project, with reasons for success or failure.

Go to:
http://biodiversity-l.iisd.org/news/iucn-releases-global-re-introduction-perspectives-2010/?referrer=biodiversity-update


For link to PDF file of the update.