Okavango Crocodile Research

Back to the wild

2011-12-20T16:34:00.001+02:00

On the 13th of December 2011 our team marked, measured and released the last remaining 100 crocodiles from the Krokovango crocodile farm. These crocs hatched from eggs collected in the wild 4 years ago. The idea of this utilization programme is that the farm raise the crocodiles until they are over 80cm in total length, thereby increasing their chances of survival once they are released back into the wild. The farm are required to release 5% of the stock they collected from the wild. The hope is that most of the crocodiles released back will survive to adulthood, thereby increasing the natural survival rate in the wild (which is around 2%). So, under natural conditions - approximately only 2% of every clutch will actually survive to adulthood. The baby croc is unfortunately on top of the menu for many predators in the wild (even other large crocodiles).

Our mission with this process, is to measure and mark each one of the released crocodiles so that if these animals are caught again in the future - we can begin to understand the success of this programme. For the last three years our team has met at the croc farm, to carry out this intense session of handling, measuring and marking! To date we have released 300 crocodiles back into the Okavango river.

Morphometric measurements

This particular size class of crocodile is not usually found along the main channel of the Okavango, as it would seem that these crocs are too big to hide from other crocs, but too small to defend territories successfully. We have noted from our previous population survey work that these crocs are more than likely spending their time in the shallower flood plains adjacent to the main channel - or are highly mobile and moving into the more seasonal swamp areas of the Delta. This makes our follow up monitoring work very difficult as our boats cannot access the shallower flood plains as easily as the main channel.

Hold..

Crocodile ranches which collect from the wild are required by CITES to carry out this release process in order to continue exporting crocodile skins. It is thus critical for the local crocodile farm to work together with our programme to continually monitor these crocodiles.

Measure, tag...

and bag.

Personally, the release of these crocodiles is always a special moment for us. Every day that we as humans spend on the river, we are generally either taking something from the system (grass, fish, reeds, water) or providing some form of disturbance (noise, boat wakes, fires). It is quite refreshing to finally be adding to the quality of the biodiversity by putting these crocodiles back into the system. We do this with the hope that each one of them will actually survive to adulthood and become successful breeders. The crocs themselves take a while to figure out their new surroundings. The first initial dives are usually quite deep as the crocs have become accustomed to shallow ponds with smooth cement floors, not quite the same in the Okavango river! Some of the crocs swim into the middle of the channel and are soon made aware of this new force of nature known as current! No doubt that some of these crocs are going to carry out some epic migrations.

The timing of the release coincides well with the fish breeding season and the oncoming flood waters from Angola. This ultimately means that with more water in the flood plains, more ideal crocodile habitat will be made available for these crocs quite soon after their release. Botswana has also implemented a restriction on fishing for the month of January, which should limit any interaction with humans for the first few weeks of their time in the wild. So, to the crocs I say - we've done what we can to make this ride as easy as possible for you. Don't trust any other crocs until you are at least 3 meters in length, eat fish when ever it is available and please....please...stay away from the cows and donkeys!

Madagascar Crocodiles

2011-10-22T05:35:00.000+02:00

Our team was privileged to be asked to join an international biodiversity and 3D filming project in one of the last true wilderness areas on the planet, the Makay Highlands of Madagascar (www.makaynature.org). Our mission was to try and find out as much information about the resident crocodile population that had been seen in the area on the first expedition to the Makay. The crocodiles were said to be very shy and difficult to see, but by joining this crew we would have all the resources we need to see these crocs and possibly even catch one for some DNA analysis. The extreme nature of the terrain and its pure isolation from any nearby villages or town, make the Makay very difficult to access. We were lucky enough to have a helicopter available to us as well as a very experienced team of rock climbers and riggers who would prepare all of the dangerous routes we would need to take to reach the isolated lakes found in these highlands.

Our base camp was situated alongside a large river system and was packed full of incredible equipment, scientists and archeologists! There was a specialist for every possible species that would be encountered. We had little time to settle and were quickly whisked away to a small isolated lake where an adult crocodile had been sighted on the last expedition. The next 7 days would be the most incredible, insane experience of my life as we climbed cliff faces, crawled through quicksand, survived numerous flash floods and did some fantastic aerial work in the chopper as well as in a two man hot air balloon! All in search of the mysterious Makay crocodiles!

The Makay crocodiles live a very interesting life. They are located right in catchment area of the Makay, which is responsible for feeding many of the large rivers flowing to the south west corner of Madagascar. Even though the conditions downstream in the large rivers are more favourable for crocodiles, these areas have dense human settlements. Illegal crocodile hunting and killing is unfortunately the norm in Madagascar and because of this persecution, the crocodiles seem to have made the trek upstream into the catchment. Here they live in harsh natural conditions, but ones free of human disturbance! After our few days of croc tracking and night surveys, we were able to figure out the general behaviours of crocodiles in the area. They rely largely on some of the permanent lakes that have formed in the deep valleys, during the dry seasons they hide in the flooded forests surrounding the lakes and live off of the small fish found in the lakes.

The summer rains had started quite close to our arrival and this brought on heavy rainfall in the catchments and extreme flash flooding in the valleys. During our time there we saw numerous signs of crocodile movement during these flash floods. It appeared that the crocodiles made use of the temporary "lagoons" that form along sandy river floors after these surging floods. These lagoons of water would only last for about 2 days at a time, but this was enough to act as temporary refuge for crocodiles carrying out lengthy night time treks (on foot!). We presume that the crocodiles are moving between the lakes (found throughout the catchment) and make use of the summer rains to improve the "traveling" conditions along the way. Daytime temperatures in the catchment reaches 50 degrees celsius often and the temporary lagoons act as good rest places for crocodiles carrying out long walks.

Our attempts at spotting, not to mention catching, were few and far between. We did however see numerous tracks of crocodiles in the dry river beds as well as two sightings of crocs actually walking in the dry river bed in the early morning and late afternoon. After many hours of night time surveying on a small inflatable boat, we eventually managed to catch a small croc and collect the DNA sample we would need. We also managed to explore some incredible river systems that fed out of the catchment area and these river systems showed some of the more conventional croc habitats that we are used to. It was our hope to find signs of nesting in these habitats as they provided all of the suitable elements a croc would need to nest successfully. We made use of the slow moving hot air balloon to patrol the streams and look for nesting sites.

After 7 days of surveying we were left with more questions than answers unfortunately, but we did successfully collect some DNA from a croc as well as record potential nesting sites and sightings of crocodiles in the area. Three lake systems were surveyed by spotlight and we have begun to put together some rough ideas about how the Makay crocs are able to survive in this very harsh and extreme environment. Again, this work has shown us the resilience of these creatures and how human pressures cause them to adapt and change their behaviour constantly. We hope to return to the Makay in the near future and carry out some more detailed capture and surveying work.

August Crocodile Diving

2011-08-20T10:11:00.009+02:00

The reason we are able to successfully dive with crocodiles in the Okavango is because of a combination of factors which are quite unique to this location. The winter temperatures are very low (reaching freezing point often), the water visibility in winter is exceptional and the water levels are dropping each day pushing a higher number of crocodiles into the main channel from the surrounding flood-plains. The low water and air temperature ensures that crocodile activity is kept to a minimum, especially while submerged.

Every year we learn more about the boundaries of this diving season and this August we established another critical aspect which defines the end point of our season - crocodile breeding. Crocodiles in the Okavango start pairing up in July already, with mating and territorial fights increasing as we move into August. Large males are scouring the main channel looking for suitable females and defending particular breeding/ basking sights that they find suitable. Very often we will find groups of up to 5 crocodiles lying together for a number of days while mating takes place. These groups are usually made up of one large male and a number of smaller females.

This August we noticed distinct changes in the underwater bahaviour of large breeding adults. We believe the crocodiles were more curious under water due to the slight change in temperature (warmer), as well as the increased testosterone/ hormone levels. For the first time, our team also experimented with rebreathers rather than conventional SCUBA. The rebreathers basically recycle oxygen and absorb CO2 in a closed system, eliminating the need to exhale out of the apparatus and cause bubbles. Although exceptional for filming and recording fish behaviour, we were not sure how the crocodiles would react.

I don't think we can accurately say whether the rebreathers caused any changed behaviour in crocodiles, but we certainly noted a change in crocodile behaviour underwater (due to the onset of the breeding season I believe). There were certainly more adults approaching the divers deliberately. At this very early stage of crocodile diving, we are not looking to encourage any interaction with crocodiles underwater so in all cases the divers would leave the water. Large adults approaching divers may be looking to investigate whether the divers are crocodiles and this may lead to aggressive behaviour, which we cannot afford. It was however very interesting to note this distinct change in behaviour and analyse what we thought the crocodile was attempting to do.

During night time surveys, we noted a distinct change in the distribution of crocodiles along the main channels. Large male crocodiles dominate along the channel with very few sub-adults around at this time. We also noted that many of the crocodiles had been involved in territorial fighting with fresh wounds apparent on many of these animals. We also found a dead 2.7m croc floating in the water which, judging by the wounds, seemed to have died in a fight with another crocodile.

It was also particularly interesting to note that crocodiles were using the the floating cave systems as feeding areas as the season went on. In the smaller, feeder channels - the catfish start feeding quite aggressively later in the season as smaller fish begin to return to the main channels from the flood plains. This large influx of small fish cause the larger predatory catfish to feed quite aggressively under the papyrus. This feeding activity attracts large crocodiles which, with the increase in temperatures, begin to actively begin feeding again.

Our team also decided to do a small photographic presentation of our images to one of the villages on the Panhandle. Our talks are directed at school children and in this particular case we used our underwater images to support our regular food-chain presentation. The idea of these talks is to help the children to understand the role of crocodiles as Keystone species in the ecosystem. In this case, the underwater images provided excellent visual points to our talk and the kids were very responsive to our message. The Botswana education system provides an excellent foundation for this type of presentation as this particular school had already formed an environmental club for the kids.

Underwater channels and caves

2011-07-24T10:57:00.007+02:00

Our team is currently well into the Okavango diving season and I can still honestly say that we continue to learn more and more with each dive that we do. We have made significant progress in finding new diving sites throughout the length of the Panhandle and each site has revealed its own hidden secrets of how it contributes to the hydrological patterns of the area. It is refreshing to now be able to investigate the underwater "channels" that are so often read about in Okavango literature. It is an incredible feeling to be in the water and actually feel the underlying currents which are hidden to the naked (dry) eye!

Picture: Graeme Duane

The papyrus certainly is afloat! We have been able to explore deep under the floating mats of papyrus and this type of diving has required a certain amount of adaption on our part. With strong lights and very strict protocol, we are able to push deeper under this vegetation which very often leads to new openings or "lagoons" as we are calling them. Its very clear that Hippo's do in fact play a significant role in the formation of these underwater tunnels and overhangs. The Hippo provide very defined underwater channels which seem to function as arteries for the Okavango river. These arteries are vital in the transport of water between the outer floodplains and the deeper main channel.

Picture: Graeme Duane

It has also become clear that the papyrus overhangs and underwater hippo channels are functioning as a very significant part of the Okavango crocodile habitat. These dark "caves" are very often used by crocodiles to avoid predation and any threats from above and below the water. Crocodiles that have been forced to dive undergo different levels of stress and these stress levels will determine how the crocodile subsequently behaves underwater. Very often the stress response requires the crocodile to retreat to a deep and dark portion of the channel to avoid strong currents and optimize its vision by sitting in a darker environment (thus making better use of outside light). For smaller crocodiles, these hiding spots may mean the difference between life and death, and having a "cave" to retreat to when faced with a threat becomes an important part of selecting an ideal piece of habitat.

Picture: Graeme Duane

Deep under the floating papyrus we have also noticed very distinct "peep holes" which provide sharp shafts of light in this dark environment. For the divers, these holes function as very useful landmarks while exploring this environment. For the crocodiles, these holes allow a hiding crocodile to quietly push its snout out of the water and take another deep breath of air should this be required. The caves also very often reveal warmer water currents as well as warmer (sometimes 2-3 degrees) river bed surface temperatures. The reason for the warmer bed temperatures is due to the decomposing layers of peat under the papyrus and this extra warmth is often welcomed by the divers who may find themselves underwater for lengthy periods. Many fish species (especially catfish) make use of this environment extensively and this of course also provides a regular source of food for the crocodiles.

Picture: Graeme Duane

So diving in the Okavango has revealed a new and very important habitat for the crocodile and this surely has to play an important part when crocodiles select basking and breeding sites. It would be good to be able to assess how fires impact this underwater habitat as fires along the Okavango provide massive impacts to crocodile nesting and breeding bahaviour. I have no doubt that burnt papyrus mats would change the structure of these caves and perhaps limit access underneath them. All of the fires occur in July-October, a critical period for crocodile breeding and nesting.

Crocodile Eyesight Underwater

2011-06-22T13:12:00.008+02:00

The diving season has begun - and this year we are hoping to fine tune some of the eyesight work we started last year. Crocodiles have always been known to have super sensitive senses that have been specially adapted to make them the super predators that they are. Very little however, is known about their eyesight and more importantly their eyesight under water. The limited studies that have been done (Fleishman et al, 1998; Walls, 1967) suggest that crocodiles are not able to focus the eye under water and are severely far sighted. No direct studies have ever been performed on Nile crocodiles and no studies have ever been carried out in the wild.

Working closely with Professor Howard Howland of Cornell University in the US, we have adapted a technique to measure the extent of crocodile focus underwater using a device that functions as a conventional photoretinoscope. With this, we can record whether crocodiles are firstly, able to focus under water and secondly whether they are focussed on subjects near to them (myopic) or only on subjects far away (hyperopic). Not only is this of scientific interest to us, but we are also very keen to understand how the crocodiles perceive us underwater when we are diving with them.

Previous work on crocodilians has clearly shown that this group of reptiles have the ability to hunt in turbid water and even in complete darkness. The crocs make use of a very fine tuned set of senses under the water as well as super sensitive "touch papillae" on the cranial scales of the croc.

Our eyesight tests require a few basic steps, firstly we need to get our device close enough to the crocodiles eye under water to ensure that we get the clear photo result we are looking for. Our technique requires us to send a source of light into the crocs eye and assess how this light is reflected back to our camera. The reflection of light will tell us whether the eye is focussed nearby (myopic) or far away (hyperopic - hopefully!). For our particular instrument, this would relate to a photo of a red crescent in the pupil of the crocs eye. A red crescent on the top portion of the pupil would mean that the eye is focussed nearby while a red crescent on the bottom portion of the pupil would mean that it is far sighted (as expected).

We have tested this on a few crocs and have come to the same conclusion each time, this technique has shown the crocs to be far sighted and thus surely, unable to focus on nearby subjects (such as divers). How and if they are able to compensate for this lack of close focus still needs to be assessed, but there is no doubt that the crocs know that we are there!

The first image shows a better lower pupil glow in a less crisp picture while the second shows a clearer image of the eye with less of a pupil glow. Each one however, clearly shows the lower portion of the pupil illuminated, proving that the crocodiles focus underwater is hyperopic (far sighted). It would be a brave diver however, that assumes that millions of years of evolution has failed to find a way to compensate for this restriction. We know that the crocs main source of food in the Panhandle is fish, and these are of course caught underwater.....

Our work this year has started off very successfully and we have managed to discover new channels and papyrus cave systems that the crocs seem to be using. We are trying to figure out how and when crocodiles would make use of these cave systems and if positioning themselves in the dark assists in some way with underwater vision? We continue to learn more and more on each dive about the response mechanisms that crocs use under water to deal with predation and conflict. Discovery of the underwater papyrus cave systems provide fresh insight to a significant habitat for crocodiles in the Okavango Panhandle. Each dive leaves us with more questions as to how these mysterious beasts are making use of this aquatic underworld.

Crocodile Resighting on SCUBA

2011-03-16T13:08:00.006+02:00

The ability to get accurate resightings of adult crocodiles can be a valuable tool in long term population density and movement studies. This type of research usually requires that you capture the animal and attach some formof ID tag to the animal that can be seen easily by the naked eye. The site of wild animals with colour tags or transmitters is not always a pleasing experience for travellers, so it is a challenge for researchers to continuously explore new ways of identifying individual animals by natural markings. Our project has in the past made use of plastic tags with ID numbers on them, but this system is only temporary and it is also very difficult to see the ID number before the croc retreats into the water. With our recent diving expeditions in the Delta, I started looking into the idea of individual markings on crocodiles that may offer us the chance to start identifying individuals at specific spots each year.

After reading up on the topic, I eventuallymanaged to adapt a technique used by Swanepoel, 1996 where the markings on the tail of the crocodile are translated into a very simple grid based numerical code. Because all of our diving trips have been documented with High Definition cameras, I also have a large archive of footage to explore and translate. With this technique, I can now begin to identify all adults we have dived with by giving them an individual code based on their tail markings. Themarkings on a crocodiles tail are very much like a finger print and each crocodiles markings are unique to that individual. The crocs tail is almost already divided into neat grids (due to the square scales), so all I had to do was assign a numerical ID to each "grid block". By using the first 9 scales (top and bottom) on either side of the tail, I can determine a unique code for each crocodile.

Without going into too much detail, the technique uses a 50% shaded rule for each block, so if half or more of the block is marked (black mark), then that grid cells value is used in the code for that side of the tail. In the end, each crocodile will have a unique "code" for either side of its tail (as markings on both sides differ). After each dive, the footage will be assessed and the "code" determined for the specific crocodile we were diving with. We can then start identifying individuals and make notes on when last they were noted in the area as well as specific behavioural traits related to that individual. It is possible to make an archive of the footage by simply taking some screen grabs of the footage, as shown below.

This technique will now allow us to start getting some valuable information on specific individuals. It is possible that this ID information could later be used in identifying specific females on a nest through the use of infra-red camera traps. We may then be able to start learning about nesting patterns by individual females and nest site fidelity. There is also an opportunity to educate guests and guides about the technique and allow them to photograph any crocs they see during boat drives, and send the pictures to our research group for "coding" ! Whatever the case, identifying individual crocodiles without having to put them through the stress of being captured, is a winner. I will soon release all the "characters" I have identified and hopefully be giving updates on who is spotted again this diving season!

Problem Croc In Town

2010-05-17T09:41:00.013+02:00

The team have recently joined forces with the Problem Animal Control unit in Maun. Were hoping to make use of relocation rather than the current method of lethal control. The adult population in the Delta have been hard hit in the past by hide hunting and are still recovering to carrying capacity.

Residents have recently spotted an adult crocodile on the Boro river in Maun and it seems our croc is becoming more confident in hunting domestic animals in the area, with a specific preference for dogs. We immediately notified the PAC and did a recce night shift to get an idea of size. We found the croc that evening and he was not shy, approaching the boat and even giving it a small nudge. The croc is close to 3 meters long and certainly a threat to people on the river. Our aim is to move the animal before the public try and take matters into their own hands.

We have attempted to capture the croc on two occasions without success, the animal has clearly become very "river wise" and has specific areas he retreats to as soon as he is threatened. The first evening he gave us very little chance and disappeared into his safe haven very quickly. We then realized that this capture cannot be carried out on a weekend due to the heavy boat traffic and human presence on the river. The next attempt was during the week and this made a clear difference, the croc was spotted early and was out in the main channel. We have plenty of "valid" excuses but after only giving us a single chance, the croc managed to slip under our noose and retreat back into the safe hideout. We called it a night at 3am after not spotting him again. We did however find his latest victims- a dog and a large barbel- nearby his hideout.

We will be attempting a capture again soon and will hopefully have a positive update on this. The intention is to move the croc to the Gomoti River where he is less likely to get into too much trouble with people.

Croc Research Images

2009-08-03T10:50:00.000+02:00

http://moremi.earth-touch.com/index.php/item/crocodile_research_in_the_okavango_delta/

Underwater Crocodiles!!

2009-08-03T10:08:00.006+02:00

I have been in Nxamaseri for the last few weeks with the Earth-Touch crew filming some incredible underwater crocodile behaviour. Our team have been venturing closer with each dive and have been rewarded with some amazing sights under the water! We have spent long periods of time with really large adults under the water and had the opportunity to really examine these animals up close. After spending time with them underwater I have immediately became more curious about there eyesight, or lack of it under the water. It has been shown that crocodiles cannot focus under water, mainly because of the nictitating membrane which closes over the eye before they submerge. This membrane prohibits the eye from adjusting its focus under water, which leads the crocs to rely more on other senses. We have also noticed that they make optimal use of the lighting conditions under water by positioning themselves in the dark edges of the river channel, normally under papyrus "caves" or overhangs. We think this allows them to identify potential prey on the surface of the water as silhouettes, we thus make a point to not stay on the surface for any longer than we need to!!

Another very interesting issue which came up was related to crocodile buoyancy. It was amazing to see how the shape of the crocs body would change as it dropped or moved closer to the surface. You could see a marked change in the body shape of the croc as it was changing its buoyancy. It still amazes me how these animals are able to adapt to both terrestrial and aquatic environments!

The very cold winter conditions are not ideally suited for us warm blooded creatures to enter the water, but in the Okavango winter is associated with excellent visibility in the water as well as the obvious reduced activity of our cold blooded friends! Check the site www.earth-touch.com for the footage of our expeditions!

Delta Nesting

2008-12-21T14:27:00.005+02:00

A recent nesting recce was conducted in the Mombo concession of Okavango Delta. The monitoring team managed to conduct a short recce of a small channel in the concession which was thought to have good potential for crocodile nesting. With support from local tour operator Wilderness Safaris, the team managed to access the low level channel by making use of "Go-Devil" outboard motors. These motors are designed to travel in shallow channels and through densely vegetated channels. Even with these new motors, we reached a section of the channel which could not be crossed and this was unfortunately the section which we hoped to survey. Previous flights over this area had suggested that large females may be using the area for nesting. This could unfortunately not be confirmed on this particular survey.

The section of the channel that was covered however, proved to have huge potential for nesting. This channel has unfortunately seen inconsistent flooding theough previous years and we suspect that for this reason, the crocs are not using these potential sites. The last 5 years have however shown more consistent levels of flow and this may lead to this area being used for nesting in the future. The habitat as shown in the image below, is ideal for nesting.

The nesting survey conditions were more stressful in this area due to the very dense concentration of wild animals! Potential sites had to investigated very cautiously and a professional guide was available through out the survey for assistance. The team noted a very high density of crocodiles in the channel and this emphasizes the high suitability of this habitat for crocodiles. The team are planning future work in this area once aerial surveys have been carried out in more detail. The program has also begun a process of open working collaborations with all tourism operators in the Delta to assist with the identification of potential crocodile nesting sites in their areas. The operators will also be educated on means of avoiding disturbance at any new sites. This working collaboration will be a huge help for the monitoring team and we hope to discover new nests for the Delta through this effort.

Survey complete and farmed crocs released!

2008-11-09T13:06:00.003+02:00

The spotlight survey is complete and ended very successfully with over 400 crocodiles counted through the single survey. The team had encouraging sightings of some large adults who are around this timeof the year for the breeding season. We also managed to get some good sightings of adults around a fresh elephant carcass in the river. The data has been processed and the neccesarry reports prepared for the wildlife department.

The DWNP and the Krokovango crocodile farm in Samochiman also requested the assistance of the team to draw up a release programme for the first batch of farm reared crocs that were collected as eggs from the wild. The farm is requred to release 5% of all wild collected eggs in order to improve the natural survivorship rate of 2%. The team went up to Samochima in order to measure and individually mark all 88 animals that were to be released. The crocs were an average total length of 1.3 meters, making them less susceptible to predation in the wild. Specific locations were selected for the release sites. These sites took habitat, stream characteristics and human presence into consideration. Along with staff from the farm, the department of wildlife and national parks and the state vet, the team successfully released 88 crocodiles back into the Okavango river. This is the first time farm reared crocs have ever been released back into wild in the Okavango system and the farm are looking forward to the next release due to take place next year. This is a major positive step for crocodile conservation in the Okavango and the team are pleased to have been a part of it! The team will be carrying out recapture sessions in the future to identify survivorship, movement and loss of condition of the released animals!

2008-09-15T14:44:00.002+02:00

Monday 15 September:
We have managed to complete the bottom section of the Okavango river from Etsatsa to Ikoga. We will be working the Phillipa channel in the next two nights and wrking our way toward Nxamasere. The croc numbers have been good and we have seen some big adults along the bottom stretch. We also managed to finally find our way into an un-surveyed channel which is known to hold a good number of nests!

The nights are chilly and the days extrememly hot! Our overnight camping spots have been incredible. The Carmine Bee Eaters and African Skimmers are also on the river at the moment! Looking forward to some very interesting nights on the Phillipa!! We will post new blogs where we can!

Mobile blogging from the field!

2008-09-10T22:32:00.004+02:00

The monitoring team will begin the 2008 spotlight surveys this week. They will travel the length of the Okavango Panhandle in 7nights, recording crocodile sightings at night. The team will try post a picture each day from the river via mobile blogger!

Rufford Small Grant

2008-06-17T10:15:00.004+02:00

The programme has recently been awarded a Rufford Small Grant Award which has given the porgramme the opportunity to purchase a new boat and motor for nesting and spotlight surveys. The monitoring programme will be based out of Nxamasere, which is very well located in the middle of the Panhandle allowing good access to the North and South of the Panhandle. The programme will also be functioning as the facilitator for a proposed wildlife sanctuary in the area, where it is hoped that a community based lodge will be developed in the future and subsequently lead to the protection of the area for crocs to nest each year with minimal disturbance. It is hoped that once a single community has commited to moving the cattle out and focussing on eco-tourism in the area, other communities will jump on board and follow a similar structure. These areas would then function as community managed resource areas which are strictly monitored and managed. The nesting and spotlight surveys begin in two months time! Stay in touch for news from the field. www.ruffordsmallgrants.org/rsg/projects/vincent_shacks

2008-02-13T10:39:00.003+02:00

New Year has arrived and new beginnings for monitoring on the Okavango! This year our programme aims to finally get started with proceedings. The aim of this programme is to set up a comprehensive, yet realistic, monitoring programme for our local wildlife department (DWNP).

With active crocodile hunting and farming operations taking place in the system, we feel there is no better time to be setting this programme up and training the wildlife scouts to implement it. The basic objectives include monitoring population trends, nests, croc-human conflict and baseline contaminant levels with added studies in genetics and movement patterns.

The programme received a boost when University of Botswana's Harry Oppenheimer Okavango Research Centre (HOORC) expressed interest to test for the presence of heavy metals and pesticides in crocodile tissue. This is an exciting project and the first of its kind in the Okavango Delta!

Population numbers will continue to be monitored by the mark-recapture programme and an exciting opportunity for tests will become available when the local crocodile farm begin their first release programme on the Okavango Panhandle. These crocs will be marked and hopefully present some very interesting data on success, movement and growth rates when (hopefully) recaptured in the future!

The first extensive nesting surveys for science will be occuring in the Delta this year. Concessionaires have expressed interest to have surveys done in their areas and this is great news for our programme. Only four nests have ever been recorded in the Delta itself!! We hope to also be involved with the Problem Animal Control unit in order to provide them with advice on relocation of problem animals rather than destruction of these crocs.

The rains this summer have been big in Ngamiland!!! The river level is still very high and word from Angola is that the river levels are rising quickly, it should be a good flood this year!

Nesting begins!

2007-10-25T10:56:00.000+02:00

A couple of trips to the Panhandle have been really productive in that I have already seen a number of potential nest sites being used and females occupying them. This is great news, especially in the Phillipa channel where the usual hive of activity is apparent over this time of the year. The Barbel runs have been moving up and down but have not been as big as previous years in the lower panhandle.

The nesting survey starts in mid November and the team will be collecting the data for the central database of Botswana Wildlife Management Association (BWMA). The area covered will be from the Mohembo border to Jedibe in the South. Will update once the survey is complete!! BB&B...vince

May 22nd- Floods??

2007-05-22T13:06:00.000+02:00

Five months into the year and were still waiting for our flood waters to hit Maun. The river beds are close to completely dry. The floods up in the Panhandle were huge, with a couple of the camps closing down completely because they were flooded out! The flood there has now dropped however, and the surge is close to Maun. Crocodile activity on the Panhandle has been minimal with all the crocs moving out into the floodplains with the water. This is normally a time when croc - human conflict isues arise as crocs are pushed closer to the edge of the river where small villages are found.

Im postin updated pictures of the flood graph as well as pictures of the Thamalakane river here in Maun as it is expected to recieve water very soon. The change in this river is dramatic and ill try get pics of the change posted as it happens. BB&B...vince

Floods 10 March 2007

2007-03-20T17:30:00.000+02:00

So it seems the first peak is drawing to a close now for the floods. Obviously not as dramatically as it started but levels are still high. Rainfall in town has been low but I havent heard anything from the people up north yet. Good rains in Angola is what we need for the second peak to rise up nicely. No more news from Maun town as Ive been in South Africa- where i experienced some intense storms and amazing rough seas on the East Coast...beaches have been washed away in parts of the coast. Might have some news in the near future regarding a trip up into the highlands of Angola to see whats going up in those parts. If all goes according to plan then we might have some water quality data from those parts to use for comparisons on our upcoming heavy metal project (er thats chemicals-no plans for a band, sorry fans). Will keep things updated as much as possible....BB&B - vince

Flood slowing down..

2007-02-21T14:54:00.000+02:00

So the latest update shows the first peak of the flood is not as huge as expected, its still high compared to the average. News from North at Katima is that they are receiving huge rain and water levels are way above average!! This might cause the Linyanti to be pretty wet this year. The rain been very quiet in Maun town, hopefully it will pick up soon! A trip up to Khwai on the weekend showed that the roads are all still fine. No more news on the Audi Camp croc, seems to be lying low.

News on the research front is that we are currently processing the research permit for the Ministry. Once the permit is in we will be carrying out some serious fund seeking!! For now Im just busy getting a better idea on locations for croc capture in the Delta and figuring out what the easiest techniques will be for different locations. The Delta presents new challenges to us as channels are alot narrower, more prone to blockage and have much higher hippo densities! Trapping will also be difficult because of the huge amount of scavengers and predators which will potentially be attracted to our fresh meat baits! This all means that we will have to re-evaluate our techniques! BB&B....vince

Flood Level: 10th February 2007

2007-02-12T15:07:00.000+02:00

The latest flood levels for february, it seems to be leveling off properly now....still pretty high compared to previous averages though. I was in Sepopa this last week and can report that the water is very high for this time of the year. Many of the islands that are normally quite accessible by foot are under water, it looks great! Lots of rain has hit Maun recently, so the water here is still at excellent levels for february! News from town is that a large Boerbol dog was taken in front of Audi camp last week by a croc. Last year I saw a 3m croc at another camp quite near Audi and i think its the same adult croc that took this dog. Hopefully it will keep its attacks more subtle or even better, move to a more quite spot along the river to avoid being shot! Will keep you posted...BB&B..vince

Flood Water!

2007-02-05T14:50:00.000+02:00

New flood graph from water affairs. The level it seems is begining to level out a little now but is still much higher than the average for this time of the year! Im off to Sepopa this week to see how things are looking on the river, especially in the Phillipa channel (our proposed sanctuary!) BB&B...vince

Expat-ditions!!

2007-02-02T15:39:00.000+02:00

A quick update of the Boro boat! Things are coming along nicely and we have managedto secure a nice 4 stroke Mariner outboard for this bad boy. Word from up north is that the floods hit Angola in a big way and big water is making its way down (see graph below). Shakawe has seen no sandbanks this year even! Seronga say the floods have hit them already too. So were expecting good water this year, which means great trips into the Delta! Ill keep updating the progress on the boat..BB&B...vince

Bend it like Bourquin

2007-01-31T14:41:00.000+02:00

Boro Boat! This is a weekly picture update on what will soon be the hottest boat on the Okavango! It is in the doctors room as we speak being put together. Check the page to see how our baby is coming on.

Sven has just left the cutting table where Doctors have given him a new back! It sounds as though things went well and he'll be back in action in no time. Hopefully the doctors have given him excercises that will mirror the "Noosing action" and he will be back in the front of the boat doing the Croc Dance soon!

Flood Level: 20th January, 2007

2007-01-30T16:02:00.000+02:00

Beginings!

2007-01-30T13:36:00.000+02:00

The first posting on the new croc blog! This is basically a newsletter and sort of an open forum for friends, fellow researchers and people in the field to stay in touch with us, send news, give advice or ask any questions. At the moment Sven and I are both very busy with our own private endevours and are doing our best to find funding for the new program. Ive found that its quite a challenge to find funding as an independent researcher as most funding agencies like to see the name of a big institution/ university behind your work. What our project is trying to do is fill the large gap between scientific research and ground level field operations. This has always been a common problem with research, especially in Botswana where alot of researchers were known for their "hit n run" policy. In this case the "hit" translates to extended periods in unbelievable surroundings, gathering data which is used for publication honours only! Well were trying something different, we want to make sure the research finds its way into management systems that will actually make a difference to our study animal! We hope that this blog will get people talking and hopefully open up some channels to potential funders and supporters of this program! BB&B....Vince