WildCRU
Thursday, March 24, 2016
Counting marbles...
Doesn't time fly.. It's been ages since I've updated this blog, but rest assured, in the meantime I have been busy collecting data on the Bornean wild cats in the field and conducting analyses in the office. In my absence this website seems to have fallen to pieces, but I intend to address this pretty soon, most likely with a whole new website.
Regardless, I've got some exciting news to share regarding a project we've been working on for many years - estimating the population density of marbled cats in Sabah. In a new (open access) PlosONE paper, we present the first estimates of marbled cat density from anywhere in their range. We show that marbled cats are found in a range of forest types, including both primary and selectively logged, but tentatively suggest that oil palm plantations may not support this elusive wild cat.
Wednesday, March 27, 2013
New paper: clouded leopard & prey activity patterns
 |
| Sunda clouded leopards terrestrial activity was shown to be mainly nocturnal |
 |
| On the menu. A samba deer calf may be an important component of Sunda clouded leopard's diet |
At long last we are beginning to churn through the mountain
of camera trapping data we have been accumulating over the last few years and to
turn it into conservation science. Our most recent paper, available from here,
explores the terrestrial activity patterns of the Sunda clouded leopard and
those of their potential ungulate prey.
I say potential, because at this stage we really don’t know
what these cats are eating – in fact, we know almost nothing about even the basic ecology of these elusive felids. We have a number of anecdotes and sightings
of clouded leopards attacking this species, and eating that, which tend to
suggest that the clouded leopard has a very varied diet, feasting on a diverse
array of mammals from monkeys to muntjacs. But we really don’t have a good
handle on what constitutes the most important prey.
Ultimately, the only way to answer this important question is to collect scat, and poke around to quantitatively assess prey composition – and this is something we are attempting to do right now. Another, indirect approach is to explore overlaps in activity between the predator and their prey – by making use of camera trap data. We might expect predator activity to be often in phase with the periods when those potential prey species are most vulnerable to their method of predation. For some predators, this may result in their activity patterns mirroring those of their prey, as has been shown in several felid-prey systems, but this may not always be the case.
Ultimately, the only way to answer this important question is to collect scat, and poke around to quantitatively assess prey composition – and this is something we are attempting to do right now. Another, indirect approach is to explore overlaps in activity between the predator and their prey – by making use of camera trap data. We might expect predator activity to be often in phase with the periods when those potential prey species are most vulnerable to their method of predation. For some predators, this may result in their activity patterns mirroring those of their prey, as has been shown in several felid-prey systems, but this may not always be the case.
 |
| Saving their bacon? Bearded pigs were shown to have a more diurnal activity pattern when clouded leopard were present - evidence of avoidance? |
With this in mind we catalogued the tens of thousands of
images for clouded leopard and prey from across our forest study sites, and
used some clever wizardry to construct models of each species’ activity patterns.
So what did we find? Firstly, Sunda clouded leopard’s terrestrial activity was
found to be primarily nocturnal, although crepuscular peaks and some diurnal
activity was also evident. We found that
of six potential ungulate prey species, Sunda clouded leopards' activity
patterns overlapped most closely with those of sambar deer and greater mouse
deer.
Interestingly, we also found that in one of our forest areas
where clouded leopard were apparently absent, bearded pigs showed a greater level
of nocturnal activity, whe compared to pig populations living alongside the predatory
felid. This finding suggests that bearded pigs may be prey species for clouded
leopards and they are capable of altering their activity pattern in response to
this risk.
Tuesday, March 26, 2013
Return to Danum Valley
 |
| A glimpse into the life of a clouded leopard. This was the first of six males we recorded. |
 |
| Male 2 wanders along a high ridgeline early in the morning |
Well it’s been a fair while since I last wrote on here – so high
time for another update on our progress with the clouded leopards of
Borneo...
Following directly on from our
survey of the Crocker Range the team and I packed up and headed to an old stomping
ground – the Danum Valley Conservation Area.
The last time we were here, way
back in 2006, we struggled to get sufficient numbers of photographic detections
of clouded leopards to estimate their density. Armed with far more, and
arguable much better, camera traps, and hopefully a little more wild cat savvy
than in the past, we headed into the forest along once familiar trails and
ridges, in search of Sabah’s elusive felids. Not wanting to make things too
easy, we set ourselves the hardest task to date (yes, even harder than Crocker’s
punishing mountains): 80 camera stations over 150 km2. This took the team a gruelling
6 months to complete, the vast majority of it spent camping at makeshift camp
sites – but thankfully it was most definitely worth it.
 |
| One of only two detections of the bay cat. In seven years we've only recorded this cat around 30 times |
We photographed an amazing 9 nine different
animals, six males and 3 females, on 93 distinct occasions, which is a record
for us! Marbled cats were coming in thick and fast too, with a total of 53 independent
photographic detections, yet we photographed surprisingly few bay cats, only
two occasions. Whilst these reddish/grey cats appear to be rarer than chicken’s
teeth, and so I wouldn’t expect to get many of them on camera, we actually
fared much better back in 2006/7, despite a hugely greater effort. I suspect
this is more a reflection of our heightened ability to place cameras in clouded
leopard areas as opposed to there being less bay cats – but more on these thought
later.
A rather nice turn-up for the
books was the Hose’s civet, which to my knowledge is the first confirmed record
for this species in Danum. Suffice to
say, the second crack at Danum Valley has been a complete success, and I thank
my team for putting in a huge effort!
Tuesday, June 19, 2012
We've got a result!
 |
| Gul surrounded by mossy forest on one of Crocker's ridgetops |
All our hard work hiking up and down Crocker Range's high ridges and river valleys has thankfully paid off.... We've got a result! I’m still tweaking the analysis, but overall we obtained 370 clouded leopard photos,
representing 51 independent capture events of 8 different animals. Two of
these animals appear to be cubs following their mother. Using the spatially
explicit capture recapture approach I estimate that clouded leopard density in the southern portion of Crocker is around 1.4 individuals per 100km2 (0.8 - 2.2 ind/100km2 95% Confidence Intervals).
This was one of the toughest surveys to date and when we first started we weren't sure we'd pull it off. So a big thank you to the team - Gil, Gul, Jasz, Nur and Ijam for doing a sterling job. Thanks also to our volunteers - Sean Proctor, Kevin Hodge and Lyndsey Stanton, who all stood up remarkably well to the rigors of Crocker Range life! Lastly, a big thank you to all the organisations and individuals that have supported us, in particular, Staff from Sabah Parks and the Sabah Wildlife Department, Karen Povey and the Clouded Leopard Project at Point Defiance Zoo, Houston Zoo and The Kaplan family.
This was one of the toughest surveys to date and when we first started we weren't sure we'd pull it off. So a big thank you to the team - Gil, Gul, Jasz, Nur and Ijam for doing a sterling job. Thanks also to our volunteers - Sean Proctor, Kevin Hodge and Lyndsey Stanton, who all stood up remarkably well to the rigors of Crocker Range life! Lastly, a big thank you to all the organisations and individuals that have supported us, in particular, Staff from Sabah Parks and the Sabah Wildlife Department, Karen Povey and the Clouded Leopard Project at Point Defiance Zoo, Houston Zoo and The Kaplan family.
Subscribe to:
Posts (Atom)
