Wednesday, 31 October 2012

Through Hills with Dale

Last weekend I had the pleasure of playing wing-man to Dale Wright on his travels to determine the conservation status of South Africa's Important Bird Areas (IBAs). Dale is Birdlife South Africa's area manager for the Western Cape. He has over 20 IBAs to keep tabs on – no small task in a province about the size of England. The IBAs range in size from small estuaries to massive mountain chains over 200km long in the case of the Swartberg.

According to Birdlife, sites are designated as Important Bird Areas based on the significant presence of bird species that fall into one or more of the following criteria: threatened, restricted-range, biome-restricted and congregatory species. More than 300 of South Africa’s bird species fall into one or more of these criteria, and they are then referred to as IBA trigger species.

Blue Hill Nature Reserve forms part of the Baviaans-Kouga IBA, but we are also nestled between the Swartberg and Outeniqua IBAs. The trigger species for all of these are predominantly the Fynbos endemic birds, grading into Karoo species for the Baviaans and Swartberg IBAs. Other trigger species include Black Harrier (associated with Renosterveld), Blue Crane, Ludwig's and Denham's Bustards and Southern-Black Korhaan. Or at least they will do after the site assessment, as several of the original trigger species were based on old information compiled by legendary Keith Barnes many years ago.

But IBAs aren't just about the birds. As Dale recently pointed out, they also conserve water. It is estimated that in the Western Cape, catchments with high densities of alien invasive vegetation or plantations supply 50 to 100 per cent less water than catchments comprising natural fynbos vegetation.

So – our plan was to drive through the Baviaanskloof and loop back via the Outeniquas and Swartberg. However, another cut off low pressure system brought more rain to the Eastern Cape, causing more flooding and road closures. Instead we headed into a mountain section I had not explored before. We found old mountain Fynbos over 40 years old – a rare thing in this climate of rampant wide-spread fires.

With more rain on the horizon we headed to George to the Garden Route Initiative, where we endured several hours of presentations – all with a positive upbeat message of active conservation projects in the area. Then to the Swartberg.

Despite the rain we decided to camp at De Hoek. Conversation and ideas kept us warm while the wind tried to keep us cool. Luckily, Saturday dawned dry and proved to be perfect for a summit of the Botha's hoek hiking trail. We recorded 5 out of 6 Fynbos endemics, the highlight for me was predicting the presence of Cape Rock-jumper and then being surrounded by them on arrival. This included my first clear views of a juvenile – with a black eye, not the red of the adult.

Sunday we headed up Perdeberg – and bagged our 6th – the elusive Protea Seedeater. All in all, a very exciting weekend – and that excludes tales of deep river water crossings and a pentad list of over 50 species along the way. Overall, our conclusion – Swartberg is a well maintained IBA, with brave battles being conducted by CapeNature to try and curb alien vegetation and other threats on the very very long boundary.

Here, a few highlight photos from the trip.

Cape Rock-thrush - male

Juvenile Cape Rockjumper

Female Cape Siskin

Male Cape Sugarbird flexing his muscles on a Protea nitida (Waboom)

Cape Bulbul - one of the few frugivores of the Fynbos

Cape Bunting

Cardinal Woodpecker (male)

a pair of Cardinal Woodpecker (female with black cap)

Dale pollinating a Protea eximia. He is going to be very busy doing this job if we loose Cape Sugarbirds!


Greater Striped Swallow "I caught a worm THIS big". 

a resting pair of Little Swifts

Speckled Pigeon

A view of the Swartberge

White-rumped Swift

Red-winged Starling harassing a White-necked Raven

The Impact of FIRE on Fynbos Birds

Most of the blog entries for this year have somehow focused on the fieldwork aspects of the research I have been conducting focused on the impact of climate change on Fynbos endemic birds, starting with the adventure by bicycle across the biome.

At the beginning of October I finished my winter survey across Protea, Erica and Restio dominated habitats of the Fynbos biome. I spent most of October entering data, and starting some preliminary analysis for a talk presented by my supervisor Phoebe Barnard at the Pan-African Ornithological Conference just finished in Arusha, Tanzania. Annelise Vlok then invited me to give a talk at the Gouritz Cluster Biosphere Reserve quarterly meeting, and knowing that she is concerned about the fate of certain Protea species with frequently returning fire intervals in the Boland area, I decided to push on with analysis of the impact of fire on Fynbos birds. After all, climate change means not only an increase in temperature, but also for the winter rainfall areas we have already recorded a decrease in annual rainfall over the last 15 years (although I'd be hard pressed to convince anyone of that this year with record high rainfall! - but such the issue between weather and climate). A drier climate means an environment more prone to fire.

In fact, Tineke Kraaij, who did her PhD at Port Elizabeth has recently published 2 papers on fire and weather on the eastern Fynbos. There are her findings in a nutshell:

1. Fynbos is fire prone and fire adapted, with the frequency, season and intensity of fires being important determinants of vegetation structure and composition
2. She cites a paper that says fire return intervals are from 8 to 40 years
3. In western sections, best fynbos recovery occurs after summer or autumn fire, while in the eastern Fynbos fire patterns are aseasonal. However, existing guidelines for the management of fire in fynbos are largely based on research carried out in the west.
4. Lightning causes 59% of fires, and she used data to calculate trends in a Fire Danger Index (FDI).
5. Mean annual FDI has increased since 1939
6. Large fires have increased in the south - eastern CFK
8. Frequent recurrence of very large fires and the virtual absence of vegetation in older postfire age classes are potential causes for concern in achieving fynbos conservation objectives

So my research focuses on Fynbos Endemic birds. A poster describing these, as well as their status as far as I am concerned, can be downloaded here:

Basically, we have 2 nectarivores: Cape Sugarbird and Orange-breasted Sunbird; 2 seed eaters: Cape Siskin and Protea Seedeater; and 2 insectivores: Victorin's Warbler and Cape Rock-jumper. All of these are listed by the IUCN as being species of Least Concern i.e. none are endangered. However, a review of the South African Bird Atlas Project (SABAP2) data shows that 2 species meet IUCN criteria for vulnerable – Cape Rock-jumper and Protea Seedeater due to a decrease in reported range >30% and this range is close to 20 000 square kilometers, another criteria for vulnerable. The thing is, these are mountain birds, so there is some concern that people who submit lists may not be getting into mountains. However, since I am looking at similar protocols, why were they reported for these sites previously? An article reviewing the data can be read here:

So in order to really understand what was going on, what was needed was a survey through the mountains by one observer to avoid observer bias, with a repeatable protocol. So I jumped on my bike and travelled 2500km to check out the situation. The following is a map of the points I conducted, highlighting the occurrence of Cape Sugarbird along the way. I did over 800 points. The pink area are selected bioregions of the Fynbos that includes mountain Fynbos, and excludes renosterveld habitats. This area is around 56 000 square kilometers.

For the analysis on fire, I use around 500 points that I had data for at the time I started to analyse the impact of fire, so it is not the complete data set. However, it does include points conducted in both winter and summer surveys in some cases. I did this to improve the number of encounters for calculating bird density in the Distance 6.0 program, which needs lots of encounters to figure out how many birds there are.

I should stress these data are preliminary – they have not yet been peer-reviewed and a final analysis will include all the data points, not just the data that was ready at the time the first analysis were needed. However, I feel the trends have been identified.

So the first chart is the distribution of Fynbos age, as determined using growth rings on Protea species. For simplicity, I've grouped the data into 4 age categories, and a mixed category for points where different fire histories were clearly present at a site. This chart shows that there are fewer areas with old Fynbos – so few for 20 years or more I had to lump them into the category of 15 years or more in order to run the density analysis.

This chart shows the average number of species I recorded per point. This was lowest for the youngest age class, around 2, and higher for points were age was greater than 10.

To show that these few species are not dominating the landscape, the following chart shows bird density for all the birds that were recorded during the survey. Again, bird density was lowest for the youngest age class, and greatest for the oldest age class.

Of all the over 3000 bird group encounters analysed, 12 species made up 62 percent of these. So the Fynbos is dominated by a handfull of species. Of these, four were considered Fynbos endemics. The following series of charts shows bird density by species for these four – where there was enough data to analyse. There were not enough group encounters to do this analysis for Cape Rock-jumper and Protea Seedeater. The strongest relationship is shown for Cape Sugarbird – where density is strongly correlated to Fynbos age. Cape Siskins on the other hand don't seem to care. Victorin's Warbler are happy once age since fire is greater than 5 years.

Orange-breasted Sunbird density in relation to fire age categories

Cape Sugarbird density in relation to fire age categories

Cape Siskin
Victorin's Warbler
Lastly, this chart shows relative capture rates of birds in mist nets from Blue Hill Nature Reserve grouped according to dietary guild. All bird groups were captured less frequently, with nectarivores the most impacted.

Relative capture rates of Fynbos bird species in burnt and unburnt Fynbos (standardised by 1000meters of net hours).

Tuesday, 23 October 2012

CREWsing in search of rare and endangered wildflowers of the Fynbos

Last week Blue Hill Nature Reserve was honoured by a visit by the Outramps CREW group. CREW (Custodians of rare and endangered wildflowers) is a SANBI volunteer initiative where anyone can go and monitor plant species of conservation concern in their area – for more information visit:

The Outramps are legendary, with outings or expeditions every week to the natural gems of the Western Cape. They have brought species of conservation concern to the attention of developers, discovered a host of new plant species, rediscovered species thought lost to science, and generally pumped loads of energy into documenting the state of the flora in the greater George area, focusing mainly on the Langeberge, Outeniqua, Swartberg, Kammanassie and Rooiberg mountain ranges. While that is a large number of sites to visit, the group was up for something new – and I'd been tantalizing Di Turner, the groups unstoppable leader, with images from the Kouga mountains for months. So finally a date was arranged and the team of interesting and inspired ladies – Jean, Russel, Gail and Anne – journeyed to Blue Hill. Photos of identified flowers are loaded on Ispot:

This is the trip report compiled by Di Turner. 

A Blue Hill in the Kouga

We’ve had some memorable trips this year, but Blue Hill in the Kouga, must rate as one of the best.  Time was limited and we were only able to spend 1 night and 2 days there.  We have promised ourselves a speedy return.

Blue Hill Nature Reserve is owned by Chris and Elaine Lee.  It is very isolated, vast and bordering on the Baviaanskloof.  For them, it was a toss-up between this and a cottage on the southern coast ofEngland.  We debated the choice, because they couldn’t be more different.  Blue Hill is in a savage part of Africa and is prone to periodic flooding, which cuts them off from civilisation.  Maintaining access roads is a major problem.  The senior Lees bought the property on condition that Alan their son and his wife Anya, would be able to live there and help them. Alan is an ornithologist and is busy doing a survey of the movement of birds in the Fynbos. Occasional volunteers give some additional assistance, but it remains a major undertaking.  It is a daunting task.

Anya and Alan made us very welcome.  The guest house is super and very tastefully decorated.  The entry road was interesting, but the old girl (Buchu Bus) made it without any problems.  We climbed into the Landcruiser bakkie and travelled towards the far north-eastern boundary.  A fire in early February burnt up huge tracts of land in the Kouga and Kammanassie and we were interested to see the veld.  Botanising was cut short by torrential rain.  Some of the party braved the elements, while some returned to the guest house for a very interesting id session.  Doing site sheets and taking photographs in that kind of weather, remains a challenge.

Despite the weather, we managed a braai.  Elaine, who has a Phd in History was both interesting and entertaining.  We spent a lovely evening in front of a big log fire.  Drenched clothes were dried in preparation for the next day.

By morning, the rain had abated and we took off on the Bloukop track which is a circular trail.  There was lots to interest us, with a number of species that were new to us.  Leucadendron pubibracteolatum (Near Threatened) was a survivor from the fire.  We saw Pegolettia retrofracta for the first time.  The dwarf shrub Crassula perforata subsp. kougaensis was an exciting find on a steep rock cliff.  It is Redlisted as Critically rare, but I suspect that this status will change rapidly, now that we are aware of the plant.  Erica flocciflora (Near threatened) was growing close to the stunning Erica passerinae.  We also saw Psoralea sp. nova (forbesii} growing on the banks of a stream.  The Vlok Boekie was invaluable for helping us id plants that we’d never seen before.  Alan’s copy was looking a little dog-eared, by the time we got back to the homestead at about 2pm.

The weather was looking threatening and we hurried to make it out over the exit road.  We were out of food and commitments at home were pressing.  The water hadn’t risen significantly, but we probably made it just in time.  As we approached George the weather got steadily worse.  By yesterday afternoon, we’d had 110 mms and it’s been raining all night.  The rivers are in full spate.  You can hear them from the top of Strawberry Hill, as they roar down the ravines.  It is still too dark to see if there’s been any damage.  Robert McKenzie has dire tales from Grahamstown, which is about to be cut off from the rest of the world.  There’s been a huge cave-in on the N2.  I have included the photograph, which Robert sent.

Hopefully all this extreme weather will have disappeared by Wednesday.  We are planning to explore a valley off the Langkloof Road. After the exciting finds at Perdepoort, we are sure that there will be something interesting there. A Garden Route Initiative meeting on Friday, means that there will not be our usual field trip this week.

What an exciting year it has been.
Groete en dankie
Di Turner
Outramps CREW Group
Southern Cape

Di and Jean

L pubibracteolatum

Psoralea sp nov

Tuesday, 16 October 2012

A leopard ate my chicken

Well, actually it ate my mom’s chicken. As part of my research project to see where our birds are going, over last few days I have had the mist-nets close to the house. This morning, at 5:15am, still without my caffeine fix, I wondered outside into the fine mist of a grey sky.

Fifteen minutes later I was wondering back up the track to the house when I got a prickling sensation up the back of my neck. Striding out in front of me were fresh tracks of a large male leopard. Fresh because the light rain from earlier had not yet dulled the sharpness of their outline in the soft sand. I glanced around to see if in fact the tracks lay over mine from a few minutes earlier, but I had followed a different line down the road.

Up ahead, towards the houses, Cape Bulbuls and a Common Fiscal were rattling an alarm. Was it due to Rania, the housecat, I had seen earlier? Or was it due to something larger?

I cautiously headed up through the garden, looking around expecting at anytime to see the spotted flank of our top predator hiding in a bush. But as I approached the Agapanthus stand at the base of our massive Belumbra tree where a chicken had hatched 9 chicks the previous week, I realised the grass was littered with feathers.

Now, instead of wild bird alarm calls, there was an ominous silence. No little peeping noises from fluffy chicks could be heard. I envisaged the leopard pouncing on the despairing fluffed up mother hen, and then swallowing helpless baby chicks. I followed the feather trail to the edge of the garden and it disappeared into the rocky hillock at the back. I did not wish to follow any further, not wanting to come into contact with him in close confines on the rocky slope. As I headed back to the house, skirting the koppie, my eyes kept searching the rocks and bushes in vain for a sight of the sleek, spotted coat that does so fine a job of hiding our elusive predator.

On a brighter note, half an hour later once the rest of the chickens had been released from their secure room, from various bushes around the garden tiny peeps of hiding chicks could be heard, and most of the cute little orphans were recovered.

That is the first time we have had the leopard move past so close to the houses. We’ll definitely move around at night a bit more cautiously from now on.     

The culprit left his fingerprints on the driveway

One of the leopards of Blue Hill Nature Reserve, maybe looking for chickens

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