Friday, September 3, 2010

Jaguars of Belize study.

(from Belize Culture Listserve )

From Planet Earth Online:

Belizean jaguar populations 'well connected'

3 September 2010, by Tamera Jones

Jaguars in Belize roam over a much wider variety of habitats than previously thought, researchers have found. They say this is good news, because it means the cats are likely to be well connected, which will ensure populations don't become isolated and inbreed.
Jaguar

Jaguar.

But it also means jaguars are more likely to come into conflict with people, presenting what the researchers call a conservation paradox.

In contrast, the news is less good for Belizean pumas. The same researchers found that they rarely venture out of the tropical rainforest and warn that with rainforest increasingly under threat, the cats' numbers could drop even further.

Jaguars (Panthera onca) and pumas (Puma concolor) coexist in Belize and sometimes prey on livestock. Before this study, researchers didn't know which habitats they were willing to use, or whether or not human activity put any pressure on their coexistence.

'Understanding how jaguars and pumas share landscapes with people is essential for devising effective conservation strategies.'
Dr Rebecca Foster, Panthera

Earlier studies suggested pumas would be more likely to hunt in a wider variety of landscapes - including those used by people – than jaguars, because they traditionally live in more varied habitats than jaguars do.

'Understanding how jaguars and pumas share landscapes with people is essential for devising effective conservation strategies,' explains Dr Rebecca Foster, who led the study from the University of Southampton but is now at conservation organisation Panthera.

'Jaguars often come into conflict with people, which is a problem for both. So we wanted to see how often they go into 'human-influenced' places,' she adds.

Foster and other researchers from the University of Southampton and Panthera describe in Biotropica how they set up a network of 178 motion-detector cameras both in rainforest in the Cockscomb Basin Wildlife Sanctuary in Belize, and in unprotected areas used by people to the east of the sanctuary.

The cameras captured thousands of images of jaguars, pumas, people and livestock over a three-year period. It was then Foster's job to sift through the pictures to find the answer to the team's question.
Jaguar

Jaguar caught on camera.

In the end she whittled thousands of photos down to 1380 useful images of around 64 to 74 different jaguars and an unknown number of pumas. Pumas are difficult to identify, because their coats are so uniform. In contrast, jaguars are much easier to identify, because each cat's spots are unique.

To their surprise, Foster and her colleagues found that jaguars roamed over both the rainforest and landscapes used by people much more than pumas did. On the other hand, pumas were less likely to leave the rainforest than jaguars were.

'We found that jaguars are making better use of all areas, which was unexpected,' Foster says.

Foster admits that right now, the researchers can't say exactly why pumas aren't as widespread as they'd anticipated, but suggests that pumas may be less tolerant of people than jaguars are.

The images also revealed that within the forest the cats use similar locations to each other, 'demonstrating an extraordinary capacity for coexistence,' which the study speculates could be down to a difference in their diets. Pumas mainly eat pacas, while jaguars rely on armadillos.

The results are invaluable for a project Foster is currently involved in at Panthera which is partly funded by the UK Darwin Inititative. The organisation is setting about establishing a 'corridor' across the jaguar's entire range in Central and South America to connect the various habitats the cats use. The aim is to make sure that jaguars are well connected to each other, encouraging a healthy mixing of genes.

Rebecca J. Foster, Bart J. Harmsen, and C. Patrick Doncaster, Habitat Use by Sympatric Jaguars and Pumas Across a Gradient of Human Disturbance in Belize, BIOTROPICA, published online 4 August 2010, doi: 10.1111/j.1744-7429.2010.00641.x

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